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BIOLOGY (1420 journals)            First | 1 2 3 4 5 6 7 8 | Last

Showing 801 - 1000 of 1720 Journals sorted alphabetically
Journal of Great Lakes Research     Hybrid Journal   (Followers: 7)
Journal of Green Science and Technology     Full-text available via subscription   (Followers: 2)
Journal of Health and Biological Sciences     Open Access  
Journal of Heredity     Hybrid Journal   (Followers: 3)
Journal of Histology & Histopathology     Open Access   (Followers: 1)
Journal of Huazhong University of Science and Technology [Medical Sciences]     Hybrid Journal  
Journal of Human Evolution     Hybrid Journal   (Followers: 17)
Journal of Hymenoptera Research     Open Access   (Followers: 3)
Journal of Ichthyology     Hybrid Journal   (Followers: 3)
Journal of Insect Behavior     Hybrid Journal   (Followers: 9)
Journal of Insect Biodiversity     Open Access   (Followers: 3)
Journal of Insect Conservation     Hybrid Journal   (Followers: 10)
Journal of Integrated OMICS     Open Access  
Journal of Integrated Pest Management     Open Access   (Followers: 1)
Journal of Integrative Environmental Sciences     Hybrid Journal   (Followers: 4)
Journal of Intelligent Transportation Systems: Technology, Planning, and Operations     Hybrid Journal   (Followers: 4)
Journal of Invertebrate Pathology     Hybrid Journal   (Followers: 3)
Journal of Landscape Ecology     Open Access   (Followers: 14)
Journal of Law and the Biosciences     Open Access   (Followers: 4)
Journal of Leukocyte Biology     Open Access   (Followers: 2)
Journal of Life and Earth Science     Open Access  
Journal of Life Sciences Research     Open Access  
Journal of Lipid Research     Full-text available via subscription   (Followers: 7)
Journal of Lipids     Open Access  
Journal of Luminescence     Hybrid Journal   (Followers: 2)
Journal of Mammalian Evolution     Hybrid Journal   (Followers: 5)
Journal of Mammalian Ova Research     Full-text available via subscription  
Journal of Mammalogy     Full-text available via subscription   (Followers: 11)
Journal of Mammary Gland Biology and Neoplasia     Hybrid Journal   (Followers: 2)
Journal of Marine and Aquatic Sciences     Open Access   (Followers: 1)
Journal of Marine Biology     Open Access   (Followers: 13)
Journal of Mathematical Biology     Hybrid Journal   (Followers: 12)
Journal of Mechanics in Medicine and Biology     Hybrid Journal  
Journal of Medical Primatology     Hybrid Journal   (Followers: 1)
Journal of Medical Toxicology     Hybrid Journal   (Followers: 4)
Journal of Medicine and Philosophy     Hybrid Journal   (Followers: 6)
Journal of Melittology     Open Access  
Journal of Membrane Biology     Hybrid Journal   (Followers: 2)
Journal of Membrane Science     Hybrid Journal   (Followers: 14)
Journal of Molecular Biology     Hybrid Journal   (Followers: 46)
Journal of Molecular Biology Research     Open Access   (Followers: 3)
Journal of Molecular Catalysis B: Enzymatic     Hybrid Journal   (Followers: 2)
Journal of Molecular Cell Biology     Hybrid Journal   (Followers: 13)
Journal of Molecular Evolution     Hybrid Journal   (Followers: 9)
Journal of Molecular Signaling     Open Access  
Journal of Molecular Structure     Hybrid Journal   (Followers: 7)
Journal of Molluscan Studies     Hybrid Journal   (Followers: 1)
Journal of Muscle Research and Cell Motility     Hybrid Journal   (Followers: 1)
Journal of Mycology     Open Access   (Followers: 6)
Journal of Nanoparticle Research     Hybrid Journal   (Followers: 3)
Journal of Nanoparticles     Open Access  
Journal of Natural History     Hybrid Journal   (Followers: 8)
Journal of Natural Products     Full-text available via subscription   (Followers: 12)
Journal of Natural Science, Biology and Medicine     Open Access   (Followers: 2)
Journal of Natural Sciences Research     Open Access   (Followers: 4)
Journal of Negative Results in BioMedicine     Open Access   (Followers: 1)
Journal of Nematology     Open Access   (Followers: 1)
Journal of Neuroscience and Behavioral Health     Open Access  
Journal of New Seeds     Hybrid Journal  
Journal of Nucleic Acids     Open Access  
Journal of Parasitology     Full-text available via subscription   (Followers: 13)
Journal of Parasitology and Vector Biology     Open Access   (Followers: 2)
Journal of Pharmacological and Toxicological Methods     Hybrid Journal   (Followers: 8)
Journal of Phycology     Hybrid Journal   (Followers: 7)
Journal of Physics D : Applied Physics     Hybrid Journal   (Followers: 13)
Journal of Physics: Condensed Matter     Hybrid Journal   (Followers: 6)
Journal of Physics: Conference Series     Open Access   (Followers: 2)
Journal of Phytopathology     Hybrid Journal   (Followers: 2)
Journal of Plankton Research     Hybrid Journal   (Followers: 3)
Journal of Plant Ecology     Hybrid Journal   (Followers: 17)
Journal of Plasma Physics     Hybrid Journal   (Followers: 20)
Journal of Pollination Ecology     Open Access  
Journal of Porphyrins and Phthalocyanines     Hybrid Journal   (Followers: 1)
Journal of Progressive Research in Biology     Open Access  
Journal of Proteome Research     Full-text available via subscription   (Followers: 12)
Journal of Proteomics     Hybrid Journal   (Followers: 11)
Journal of Purdue Undergraduate Research     Open Access   (Followers: 1)
Journal of Radiation Research and Applied Sciences     Open Access   (Followers: 2)
Journal of Risk Research     Hybrid Journal   (Followers: 7)
Journal of Science of the University of Kelaniya Sri Lanka     Open Access  
Journal of Seed Science     Open Access  
Journal of Signal Transduction     Open Access   (Followers: 2)
Journal of Stem Cell Research & Therapy     Open Access   (Followers: 2)
Journal of Stored Products Research     Hybrid Journal  
Journal of Structural and Functional Genomics     Hybrid Journal   (Followers: 1)
Journal of Structural Biology     Hybrid Journal   (Followers: 8)
Journal of Sustainable Bioenergy Systems     Full-text available via subscription   (Followers: 1)
Journal of Sustainable Society     Open Access   (Followers: 6)
Journal of Systematic Palaeontology     Hybrid Journal   (Followers: 7)
Journal of Systematics Evolution     Open Access   (Followers: 5)
Journal of the American Mosquito Control Association     Full-text available via subscription   (Followers: 1)
Journal of the Korean Society for Applied Biological Chemistry     Hybrid Journal  
Journal of the Renin-Angiotensin-Aldosterone System     Open Access  
Journal of the Royal Society of New Zealand     Hybrid Journal   (Followers: 12)
Journal of the Selva Andina Research Society     Open Access   (Followers: 2)
Journal of the South Carolina Academy of Science     Open Access  
Journal of Theoretical Biology     Hybrid Journal   (Followers: 12)
Journal of Thermal Biology     Hybrid Journal   (Followers: 3)
Journal of Thyroid Research     Open Access  
Journal of Tissue Engineering     Open Access   (Followers: 6)
Journal of Vacuum Science & Technology A     Full-text available via subscription   (Followers: 2)
Journal of Vacuum Science & Technology B     Full-text available via subscription   (Followers: 2)
Journal of Vector Ecology     Free   (Followers: 3)
Journal of Vegetation Science     Full-text available via subscription   (Followers: 20)
Journal of Vinyl & Additive Technology     Hybrid Journal  
Journal of Virological Methods     Hybrid Journal   (Followers: 6)
Journal of Virology     Hybrid Journal   (Followers: 31)
Journal of Visualized Experiments     Full-text available via subscription   (Followers: 3)
Journal of Yeast and Fungal Research     Open Access   (Followers: 1)
Journal of Zhejiang University - Science B     Hybrid Journal  
Jurnal Fitopatologi Indonesia     Open Access  
Jurnal Penelitian Sains (JPS)     Open Access  
Jurnal Teknosains     Open Access  
Kahramanmaras Sutcu Imam University Journal Of Natural Sciences     Open Access  
Karbala International Journal of Modern Science     Open Access   (Followers: 3)
Kennedy Institute of Ethics Journal     Full-text available via subscription   (Followers: 5)
Kew Bulletin     Hybrid Journal   (Followers: 1)
KINOME     Open Access  
Knowledge and Management of Aquatic Ecosystems     Open Access   (Followers: 3)
Koedoe : African Protected Area Conservation and Science     Open Access   (Followers: 6)
Kurtziana     Open Access  
Landscape and Ecological Engineering     Hybrid Journal   (Followers: 4)
Large Marine Ecosystems     Full-text available via subscription  
Le Naturaliste canadien     Full-text available via subscription  
Letters in Mathematical Physics     Hybrid Journal   (Followers: 4)
Life     Open Access   (Followers: 2)
Life Sciences in Space Research     Hybrid Journal   (Followers: 1)
Life Sciences, Society and Policy     Open Access  
Limnological Papers     Open Access  
Lipid Insights     Open Access  
Lipid Technology     Hybrid Journal   (Followers: 2)
Lipids     Hybrid Journal   (Followers: 2)
Lipids in Health and Disease     Open Access  
Luminescence     Hybrid Journal   (Followers: 3)
mAbs     Full-text available via subscription   (Followers: 14)
Macromolecular Bioscience     Hybrid Journal   (Followers: 2)
Macromolecular Reaction Engineering     Hybrid Journal  
Madroño     Full-text available via subscription   (Followers: 1)
Malacologia     Full-text available via subscription  
Malacologica Bohemoslovaca     Open Access   (Followers: 1)
Malawi Journal of Science and Technology     Open Access   (Followers: 6)
Mammal Review     Hybrid Journal   (Followers: 7)
Mammal Study     Full-text available via subscription  
Mammalian Biology - Zeitschrift für Säugetierkunde     Hybrid Journal   (Followers: 4)
Mammalian Genome     Hybrid Journal   (Followers: 3)
Mammalian Species     Full-text available via subscription   (Followers: 1)
Manufacturing Engineer     Hybrid Journal   (Followers: 9)
Marine Biodiversity     Hybrid Journal   (Followers: 11)
Marine Biodiversity Records     Open Access   (Followers: 5)
Marine Biology     Hybrid Journal   (Followers: 59)
Marine Biotechnology     Hybrid Journal   (Followers: 5)
Marine Mammal Science     Hybrid Journal   (Followers: 9)
Materials Science and Engineering: C     Hybrid Journal   (Followers: 19)
Materials Technology : Advanced Performance Materials     Hybrid Journal   (Followers: 5)
Mathematical Biosciences     Hybrid Journal   (Followers: 3)
Mathematical Medicine and Biology: A Journal of the IMA     Hybrid Journal   (Followers: 2)
Mathematical Physics, Analysis and Geometry     Hybrid Journal   (Followers: 1)
Mathematical Problems in Engineering     Open Access   (Followers: 3)
Matrix Biology     Hybrid Journal   (Followers: 1)
mBio     Open Access   (Followers: 7)
Mechanisms of Ageing and Development     Hybrid Journal   (Followers: 3)
Mechanisms of Development     Hybrid Journal   (Followers: 5)
Médecine Nucléaire     Full-text available via subscription  
médecine/sciences     Full-text available via subscription   (Followers: 1)
Medical and Biological Engineering and Computing     Hybrid Journal   (Followers: 2)
Medical and Biological Sciences     Open Access  
Medical Engineering & Physics     Hybrid Journal   (Followers: 9)
Mediterranean Journal of Biosciences     Open Access  
Membrane Protein Transport     Full-text available via subscription   (Followers: 2)
Memoirs of the Association of Australasian Palaeontologists     Full-text available via subscription   (Followers: 2)
Messenger     Full-text available via subscription  
Metabolic Engineering     Hybrid Journal   (Followers: 13)
Metabolites     Open Access  
Metabolomics     Hybrid Journal   (Followers: 7)
Metallomics     Full-text available via subscription  
Metamorfosa : Journal of Bilogical Sciences     Open Access   (Followers: 1)
Methods     Hybrid Journal   (Followers: 13)
Methods in Cell Biology     Full-text available via subscription   (Followers: 6)
Methods in Cell Science     Hybrid Journal   (Followers: 3)
Methods in Ecology and Evolution     Partially Free   (Followers: 30)
Micologia Aplicada Internacional     Open Access  
Microarrays     Open Access  
Micron     Hybrid Journal  
Mitochondrial DNA     Hybrid Journal   (Followers: 4)
Mitochondrion     Hybrid Journal   (Followers: 3)
Modelling and Simulation in Engineering     Open Access   (Followers: 3)
Modelling and Simulation in Materials Science and Engineering     Hybrid Journal   (Followers: 7)
Modern Chemotherapy     Open Access  
Molecular & Cellular Proteomics     Full-text available via subscription   (Followers: 13)
Molecular & Cellular Toxicology     Hybrid Journal   (Followers: 2)
Molecular and Biochemical Parasitology     Hybrid Journal   (Followers: 2)
Molecular and Cellular Biochemistry     Hybrid Journal   (Followers: 4)
Molecular and Cellular Biology     Hybrid Journal   (Followers: 22)
Molecular Based Mathematical Biology     Open Access   (Followers: 1)
Molecular Biology     Hybrid Journal   (Followers: 10)
Molecular Biology and Evolution     Hybrid Journal   (Followers: 110)
Molecular Biology International     Open Access   (Followers: 2)
Molecular Biology of the Cell     Partially Free   (Followers: 20)
Molecular Biology Reports     Hybrid Journal   (Followers: 4)
Molecular Brain     Open Access   (Followers: 2)

  First | 1 2 3 4 5 6 7 8 | Last

Journal Cover Anaerobe
  [SJR: 1.066]   [H-I: 51]   [4 followers]  Follow
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 1075-9964 - ISSN (Online) 1095-8274
   Published by Elsevier Homepage  [3041 journals]
  • Stress hormone epinephrine (adrenaline) and norepinephrine (noradrenaline)
           effects on the anaerobic bacteria
    • Authors: Lyudmila Boyanova
      Pages: 13 - 19
      Abstract: Publication date: April 2017
      Source:Anaerobe, Volume 44
      Author(s): Lyudmila Boyanova
      Microbial endocrinology is a relatively new research area that already encompasses the anaerobes. Stress hormones, epinephrine and norepinephrine, can affect the growth of anaerobic bacteria such as Fusobacterium nucleatum, Prevotella spp., Porhyromonas spp., Tanerella forsythia and Propionibacterium acnes and can increase virulence gene expression, iron acquisition and many virulence factors of some anaerobic species such as Clostridium perfringens, Porphyromonas gingivalis and Brachyspira pilosicoli. Epinephrine and norepinephrine effects can lead to a growth increase or decrease, or no effect on the growth of the anaerobes. The effects are species-specific and perhaps strain-specific. Discrepancies in the results of some studies can be due to the different methods and media used, catecholamine concentrations, measurement techniques and the low number of strains tested. Biological effects of the stress hormones on the anaerobes may range from halitosis and a worsening of periodontal diseases to tissue damages and atherosclerotic plaque ruptures. Optimizations of the research methods and a detailed assessment of the catecholamine effects in conditions mimicking those in affected organs and tissues, as well as the effects on the quorum sensing and virulence of the anaerobes and the full spectrum of biological consequences of the effects are interesting topics for further evaluation.

      PubDate: 2017-01-15T19:43:04Z
      DOI: 10.1016/j.anaerobe.2017.01.003
      Issue No: Vol. 44 (2017)
  • Isolation of Clostridium perfringens type A from wild bharals (Pseudois
           nayaur) following sudden death in Tibet, China
    • Authors: Lingwei Zhu; Wei Zhou; Tiecheng Wang; Haiyang Xiang; Xue Ji; Yixiao Han; Yuan Tian; Yang Sun; Jun Liu; Xuejun Guo
      Pages: 20 - 22
      Abstract: Publication date: April 2017
      Source:Anaerobe, Volume 44
      Author(s): Lingwei Zhu, Wei Zhou, Tiecheng Wang, Haiyang Xiang, Xue Ji, Yixiao Han, Yuan Tian, Yang Sun, Jun Liu, Xuejun Guo
      Dozens of wild bharals died suddenly in Tibet. Necropsy showed severe congestion and hemorrhage in multiple organs, with large numbers of Gram-positive bacilli. Strains of Clostridium perfringens type A were isolated from the different organs and the intestinal contents. The other possible pathogens were ruled out by PCR.

      PubDate: 2017-01-15T19:43:04Z
      DOI: 10.1016/j.anaerobe.2017.01.004
      Issue No: Vol. 44 (2017)
  • Antimicrobial activity of stable hemiaminals against Porphyromonas
    • Authors: Teresa Olczak; Michał Śmiga; Anna Kwiecień; Marcin Bielecki; Robert Wróbel; Mariusz Olczak; Zbigniew Ciunik
      Pages: 27 - 33
      Abstract: Publication date: April 2017
      Source:Anaerobe, Volume 44
      Author(s): Teresa Olczak, Michał Śmiga, Anna Kwiecień, Marcin Bielecki, Robert Wróbel, Mariusz Olczak, Zbigniew Ciunik
      Porphyromonas gingivalis is a major etiologic agent and a key pathogen responsible for the development and progression of chronic periodontitis. Controlling the number of periodontal pathogens is one of the primary actions for maintaining oral health; therefore, active compounds with a capacity to exert antimicrobial activity have received considerable attention as they may represent potential new therapeutic agents for the treatment of chronic periodontitis. Heterocyclic compounds possessing 1,2,4- or 1,2,3-triazoles are known for several biological activities, including antibacterial properties. Among them are stable hemiaminals which can be obtained in reaction between nitrobenzaldehyde derivatives and 4-amino-1,2,4-triazole or 4-amino-3,5-dimethyl-1,2,4-triazole. In this study, we selected two relatively stable hemiaminals: (2,4-dinitrophenyl)(4H-1,2,4-triazole-4-ylamino)methanol (24DNTAM) and (2,4-dinitrophenyl)(4H-3,5-dimethyl-1,2,4-triazole-4-ylamino)methanol (24DNDMTAM). Both compounds showed promising anti-P. gingivalis activity, higher against ATCC 33277 strain as compared to A7436 strain. The lowest hemiaminal concentration inhibiting visible planktonic bacterial growth under high-iron/heme conditions was ∼0.06 mg/ml, and the lowest hemiaminal concentration showing killing of bacteria was ∼0.25 mg/ml. Antimicrobial activity was also observed against P. gingivalis grown on blood agar plates. Slightly higher antimicrobial activity of both compounds was observed when P. gingivalis was grown in co-cultures with epithelial HeLa cells under low-iron/heme conditions, which mimic those occurring in vivo. 24DNTAM was more effective against P. gingivalis, but exhibited higher cytotoxic activity against epithelial and red blood cells, as compared with 24DNDMTAM. We conclude that both hemiaminals might originate a novel group of biologically important molecules.
      Graphical abstract image

      PubDate: 2017-01-22T20:32:01Z
      DOI: 10.1016/j.anaerobe.2017.01.005
      Issue No: Vol. 44 (2017)
  • C. difficile PCR-ribotype 023 might go undetected when using ChromId
           C. difficile agar
    • Authors: E. Reigadas; L. Alcalá; M. Marín; A. Martín; E. Bouza
      Pages: 34 - 35
      Abstract: Publication date: April 2017
      Source:Anaerobe, Volume 44
      Author(s): E. Reigadas, L. Alcalá, M. Marín, A. Martín, E. Bouza
      We compared the performance of the new chromogenic medium ChromID C. difficile with that of CLO agar. ChromID C. difficile agar is a sensitive medium that can accelerate the presumptive identification of C. difficile, however ribotype 023 might go undetected when using this chromogenic medium.

      PubDate: 2017-01-22T20:32:01Z
      DOI: 10.1016/j.anaerobe.2017.01.008
      Issue No: Vol. 44 (2017)
  • Prevalence and molecular typing of Clostridium perfringens in captive
           wildlife in India
    • Authors: Arockiasamy Arun Prince Milton; Rajesh Kumar Agarwal; Govindarajan Bhuvana Priya; Mani Saminathan; Manivasagam Aravind; Avinash Reddy; C.K. Athira; Thadiyampuram Ramees; Anil Kumar Sharma; Ashok Kumar
      Pages: 55 - 57
      Abstract: Publication date: April 2017
      Source:Anaerobe, Volume 44
      Author(s): Arockiasamy Arun Prince Milton, Rajesh Kumar Agarwal, Govindarajan Bhuvana Priya, Mani Saminathan, Manivasagam Aravind, Avinash Reddy, C.K. Athira, Thadiyampuram Ramees, Anil Kumar Sharma, Ashok Kumar
      The prevalence of Clostridium perfringens in captive wildlife in India has not been reported. The objective of the study was to determine the fecal prevalence of C. perfringens in captive wildlife in India. The prevalence in captive wild ruminants, non-ruminants, birds and caretakers were 34.1%, 36%, 22.5% and 6.7%, respectively. Toxinotyping of C. perfringens indicated that the predominant type was type A with a prevalence rate of 69.7%, followed by type A with cpb2 gene (28.3%) and type B (2.%).

      PubDate: 2017-02-05T21:42:52Z
      DOI: 10.1016/j.anaerobe.2017.01.011
      Issue No: Vol. 44 (2017)
  • Olegusella massiliensis gen. nov., sp. nov., strain KHD7T, a new bacterial
           genus isolated from the female genital tract of a patient with bacterial
    • Authors: Khoudia Diop; Awa Diop; Florence Bretelle; Frédéric Cadoret; Caroline Michelle; Magali Richez; Jean-François Cocallemen; Didier Raoult; Pierre-Edouard Fournier; Florence Fenollar
      Pages: 87 - 95
      Abstract: Publication date: Available online 20 February 2017
      Author(s): Khoudia Diop, Awa Diop, Florence Bretelle, Frédéric Cadoret, Caroline Michelle, Magali Richez, Jean-François Cocallemen, Didier Raoult, Pierre-Edouard Fournier, Florence Fenollar
      Strain KHD7T, a Gram-stain-positive rod-shaped, non-sporulating, strictly anaerobic bacterium, was isolated from the vaginal swab of a woman with bacterial vaginosis. We studied its phenotypic characteristics and sequenced its complete genome. The major fatty acids were C16:0 (44%), C18:2n6 (22%), and C18:1n9 (14%). The 1,806,744 bp long genome exhibited 49.24% G+C content; 1549 protein-coding and 51 RNA genes. Strain KHD7T exhibited a 93.5% 16S rRNA similarity with Olsenella uli, the phylogenetically closest species in the family Coriobacteriaceae. Therefore, strain KHD7T is sufficiently distinct to represent a new genus, for which we propose the name Olegusella massiliensis gen. nov., sp. nov. The type strain is KHD7T.

      PubDate: 2017-02-23T16:39:25Z
      DOI: 10.1016/j.anaerobe.2017.02.012
      Issue No: Vol. 44 (2017)
  • First report on sepsis caused by Porphyromonas pogonae
    • Authors: Percy Schröttner; Katharina Heidrich; Wolfram W. Rudolph; Friedrich Stölzel; Enno Jacobs; Florian Gunzer
      Pages: 96 - 98
      Abstract: Publication date: April 2017
      Source:Anaerobe, Volume 44
      Author(s): Percy Schröttner, Katharina Heidrich, Wolfram W. Rudolph, Friedrich Stölzel, Enno Jacobs, Florian Gunzer
      We report on a 62 year old patient who developed sepsis due to an infection caused by Porphyromonas pogonae, a recently described species of the bacterial genus Porphyromonas. This is the first case of an invasive infection with this pathogen.

      PubDate: 2017-03-03T17:13:07Z
      DOI: 10.1016/j.anaerobe.2017.02.016
      Issue No: Vol. 44 (2017)
  • Quantitative proteomic analysis of extracellular matrix extracted from
           mono- and dual-species biofilms of Fusobacterium nucleatum and
           Porphyromonas gingivalis
    • Authors: Marwan Mansoor Ali Mohammed; Veronika Kuchařová Pettersen; Audun H. Nerland; Harald G. Wiker; Vidar Bakken
      Pages: 133 - 142
      Abstract: Publication date: Available online 9 March 2017
      Author(s): Marwan Mansoor Ali Mohammed, Veronika Kuchařová Pettersen, Audun H. Nerland, Harald G. Wiker, Vidar Bakken
      The Gram-negative bacteria Fusobacterium nucleatum and Porphyromonas gingivalis are members of a complex dental biofilm associated with periodontal disease. In this study, we cultured F. nucleatum and P. gingivalis as mono- and dual-species biofilms, and analyzed the protein composition of the biofilms extracellular polymeric matrix (EPM) by high-resolution liquid chromatography-tandem mass spectrometry. Label-free quantitative proteomic analysis was used for identification of proteins and sequence-based functional characterization for their classification and prediction of possible roles in EPM. We identified 542, 93 and 280 proteins in the matrix of F. nucleatum, P. gingivalis, and the dual-species biofilm, respectively. Nearly 70% of all EPM proteins in the dual-species biofilm originated from F. nucleatum, and a majority of these were cytoplasmic proteins, suggesting an enhanced lysis of F. nucleatum cells. The proteomic analysis also indicated an interaction between the two species: 22 F. nucleatum proteins showed differential levels between the mono and dual-species EPMs, and 11 proteins (8 and 3 from F. nucleatum and P. gingivalis, respectively) were exclusively detected in the dual-species EPM. Oxidoreductases and chaperones were among the most abundant proteins identified in all three EPMs. The biofilm matrices in addition contained several known and hypothetical virulence proteins, which can mediate adhesion to the host cells and disintegration of the periodontal tissues. This study demonstrated that the biofilm matrix of two important periodontal pathogens consists of a multitude of proteins whose amounts and functionalities vary largely. Relatively high levels of several of the detected proteins might facilitate their potential use as targets for the inhibition of biofilm development.

      PubDate: 2017-03-12T17:58:06Z
      DOI: 10.1016/j.anaerobe.2017.03.002
      Issue No: Vol. 44 (2017)
  • Three variants of the leukotoxin gene in human isolates of Fusobacterium
           necrophorum subspecies funduliforme
    • Authors: Karin Holm; Mattias Collin; Lena Hagelskjær-Kristensen; Anders Jensen; Magnus Rasmussen
      Abstract: Publication date: Available online 19 March 2017
      Author(s): Karin Holm, Mattias Collin, Lena Hagelskjær-Kristensen, Anders Jensen, Magnus Rasmussen
      Leukotoxin is a well-known virulence factor of animal isolates of Fusobacterium necrophorum subspecies necrophorum, and is also expressed by animal isolates of subspecies funduliforme, whereas its presence in isolates from humans has not been fully established. In this study we found that the leukotoxin gene was present in all tested F. necrophorum isolates from humans. Three sequence variants were found, two of which have not been described previously. The sequence types correlated to source of infection. Further studies are needed to examine the role of the leukotoxin in human infections.

      PubDate: 2017-03-20T21:19:39Z
      DOI: 10.1016/j.anaerobe.2017.03.016
  • Effect of bioaugmentation by cellulolytic bacteria enriched from sheep
           rumen on methane production from wheat straw
    • Authors: E. Gozde Ozbayram; Sabine Kleinsteuber; Marcell Nikolausz; Bahar Ince; Orhan Ince
      Abstract: Publication date: Available online 18 March 2017
      Author(s): E. Gozde Ozbayram, Sabine Kleinsteuber, Marcell Nikolausz, Bahar Ince, Orhan Ince
      The aim of this study was to determine the potential of bioaugmentation with cellulolytic rumen microbiota to enhance the anaerobic digestion of lignocellulosic feedstock. An anaerobic cellulolytic culture was enriched from sheep rumen fluid using wheat straw as substrate under mesophilic conditions. To investigate the effects of bioaugmentation on methane production from straw, the enrichment culture was added to batch reactors in proportions of 2% (Set-1) and 4% (Set-2) of the microbial cell number of the standard inoculum slurry. The methane production in the bioaugmented reactors was higher than in the control reactors. After 30 days of batch incubation, the average methane yield was 154 mLN CH4 gVS −1 in the control reactors. Addition of 2% enrichment culture did not enhance methane production, whereas in Set-2 the methane yield was increased by 27%. The bacterial communities were examined by 454 amplicon sequencing of 16S rRNA genes, while terminal restriction fragment length polymorphism (T-RFLP) fingerprinting of mcrA genes was applied to analyze the methanogenic communities. The results highlighted that relative abundances of Ruminococcaceae and Lachnospiraceae increased during the enrichment. However, Cloacamonaceae, which were abundant in the standard inoculum, dominated the bacterial communities of all batch reactors. T-RFLP profiles revealed that Methanobacteriales were predominant in the rumen fluid, whereas the enrichment culture was dominated by Methanosarcinales. In the batch rectors, the most abundant methanogens were affiliated to Methanobacteriales and Methanomicrobiales. Our results suggest that bioaugmentation with sheep rumen enrichment cultures can enhance the performance of digesters treating lignocellulosic feedstock.
      Graphical abstract image

      PubDate: 2017-03-20T21:19:39Z
      DOI: 10.1016/j.anaerobe.2017.03.013
  • The effect of penicillin administration in early life on murine gut
           microbiota and blood lymphocyte subsets
    • Authors: Jaroslaw Daniluk; Urszula Daniluk; Malgorzata Rusak; Milena Dabrowska; Joanna Reszec; Magdalena Garbowicz; Kinga Humińska; Andrzej Dabrowski
      Abstract: Publication date: Available online 18 March 2017
      Author(s): Jaroslaw Daniluk, Urszula Daniluk, Malgorzata Rusak, Milena Dabrowska, Joanna Reszec, Magdalena Garbowicz, Kinga Humińska, Andrzej Dabrowski
      Background and aim Antibiotics have many beneficial effects but their uncontrolled use may lead to increased risk of serious diseases in the future. Our hypothesis is that an early antibiotic exposition may affect immune system by altering gut microbiota. Therefore, the aim of the study was to determine the effect of penicillin treatment on gut microorganisms and immune system of mice. Methods: 21-days old C57BL6/J/cmdb male mice were treated with low-dose of penicillin (study group) or water only (control group) for 4 weeks. Tissue and stool samples for histology or microbiome assessment and peripheral blood for CBC and flow cytometry evaluation were collected. Results: We found high variability in microbiota composition at different taxonomic levels between littermate mice kept in the same conditions, independently of treatment regimen. Interestingly, low-dose of penicillin caused significant increase of Parabacteroides goldsteinii in stool and in colon tissue in comparison to control group (9.5% vs. 4.9%, p = 0.008 and 10.7% vs. 6.1%, p = 0.008, respectively). Moreover, mice treated with penicillin demonstrated significantly elevated percentage of B cells (median 10.5% vs 8.0%, p = 0.01) and decrease in the percentage of total CD4+ cell (median 75.4% vs 82.5%, p = 0.0039) with subsequent changes among subsets - increased percentage of regulatory T cells (Treg), T helper 1 (Th1) and T helper 2 (Th2) cells. Conclusion: Our study showed significant effect of penicillin on B and T cells in peripheral blood of young mice. This effect may be mediated through changes in gut microbiota represented by the expansion of Parabacteroides goldsteinii.

      PubDate: 2017-03-20T21:19:39Z
      DOI: 10.1016/j.anaerobe.2017.03.015
  • Effect of operating temperature on anaerobic digestion of the Brazilian
           waterweed Egeria densa and its microbial community
    • Authors: Keiko Watanabe; Mitsuhiko Koyama; Junko Ueda; Syuhei Ban; Norio Kurosawa; Tatsuki Toda
      Abstract: Publication date: Available online 16 March 2017
      Author(s): Keiko Watanabe, Mitsuhiko Koyama, Junko Ueda, Syuhei Ban, Norio Kurosawa, Tatsuki Toda
      To develop an effective treatment for the globally invasive Brazilian waterweed Egeria densa, anaerobic digestion was observed at 37 °C, 55 °C, and 65 °C. The average methane production rate at 55 °C was 220 mL L−1 day−1, which was two-fold that at 37 °C and 65 °C. Volatile fatty acid accumulation was detected under thermophilic conditions; however, although there was methane production, the system did not shutdown. The microbial communities differed between mesophilic (37 °C) and thermophilic (55 °C and 65 °C) conditions. A bacterial community consisting of the phyla Bacteroidetes (43%), Firmicutes (37%), Proteobacteria (9%), Synergistetes (5%), Spirochaetes (1%), and unclassified bacteria (5%) were detected under mesophilic condition. In contrast, the phylum Firmicutes was dominant under thermophilic conditions. In the archaeal community, Methanosaeta concilii (40%), Methanolinea sp. (17%), and unclassified euryarchaeota (43%) were detected under mesophilic condition. Methanosarcina thermophila (87% at 55 °C, 54% at 65 °C) and Methanothermobacter thermautotrophicus (13% at 55 °C, 46% at 65 °C) were detected under thermophilic conditions. At both 37 °C and 55 °C, acetoclastic methanogenesis likely occurred because of the lower abundance of hydrogenotrophic methanogens. At 65 °C, the growth of the acetoclastic methanogen Methanosarcina thermophila was limited by the high temperature, therefore, acetate oxidation and hydrogenotrophic methanogenesis may have occurred.

      PubDate: 2017-03-20T21:19:39Z
      DOI: 10.1016/j.anaerobe.2017.03.014
  • Characterization of vaginal Lactobacillus species by rplK -based multiplex
           qPCR in Russian women
    • Authors: Vladimir V. Demkin; Stanislav I. Koshechkin
      Abstract: Publication date: Available online 14 March 2017
      Author(s): Vladimir V. Demkin, Stanislav I. Koshechkin
      We describe a multiplex qPCR assay for identification and quantitative assessment of a set of vaginal Lactobacillus species, including L. acidophilus, L. crispatus, L. gasseri, L. helveticus, L. iners, and L. jensenii. The assay extends the previously developed qPCR method for Lactobacillus detection and total quantification based on targeting the rplK gene. Both assays use only single pair of primers and a set of probes combined in three reactions, comprising a vaginal Lactobacillus diagnostic assay panel. The utility of the diagnostic panel was evaluated by analyzing of vaginal swab specimens from 145 patients with different status of vaginal health. Most frequently, only one Lactobacillus species was dominant (68,9%), mostly L. crispatus (18,6%) or L. iners (33,1%), but two or three Lactobacillus species were also being simultaneously detected (24,9%). The diagnostic panel will facilitate investigations of the role of Lactobacillus species in the health of the female reproductive system and promote studies of variability of the vaginal microbiota.

      PubDate: 2017-03-20T21:19:39Z
      DOI: 10.1016/j.anaerobe.2017.03.011
  • Distribution and phylogeny of Brachyspira spp. in human intestinal
           spirochetosis revealed by FISH and 16S rRNA-gene analysis
    • Authors: Pablo Rojas; Annett Petrich; Julia Schulze; Alexandra Wiessner; Christoph Loddenkemper; Hans-Jörg Epple; William Sterlacci; Michael Vieth; Judith Kikhney; Annette Moter
      Abstract: Publication date: Available online 12 March 2017
      Author(s): Pablo Rojas, Annett Petrich, Julia Schulze, Alexandra Wiessner, Christoph Loddenkemper, Hans-Jörg Epple, William Sterlacci, Michael Vieth, Judith Kikhney, Annette Moter
      During six years as National Reference Laboratory for Spirochetes we investigated 149 intestinal biopsies from 91 patients, which were histopathologically diagnosed with human intestinal spirochetosis (HIS), using fluorescence in situ hybridization (FISH) combined with 16S rRNA gene PCR and sequencing. Aim of this study was to complement histopathological findings with FISH and PCR for definite diagnosis and species identification of the causative pathogens. HIS is characterized by colonization of the colonic mucosa of the human distal intestinal tract by Brachyspira spp. Microbiological diagnosis of HIS is not performed, because of the fastidious nature and slow growth of Brachyspira spp. in culture. In clinical practice, diagnosis of HIS relies solely on histopathology without differentiation of the spirochetes. We used a previously described FISH probe to detect and identify Brachyspira spp. in histological gut biopsies. FISH allowed rapid visualization and identification of Brachyspira spp. in 77 patients. In most cases, the bright FISH signal already allowed rapid localization of Brachyspira spp. at 400× magnification. By sequencing, 53 cases could be assigned to the B. aalborgi lineage including “B. ibaraki” and “B. hominis”, and 23 cases to B. pilosicoli. One case showed mixed colonization. The cases reported here reaffirm all major HIS Brachyspira spp. clusters already described. However, the phylogenetic diversity seems to be even greater than previously reported. In 14 cases, we could not confirm HIS by either FISH or PCR, but found colonization of the epithelium by rods and cocci, indicating misdiagnosis by histopathology. FISH in combination with molecular identification by 16S rRNA gene sequencing has proved to be a valuable addition to histopathology. It provides definite diagnosis of HIS and allows insights into phylogeny and distribution of Brachyspira spp. HIS should be considered as a differential diagnosis in diarrhea of unknown origin, particularly in patients from risk groups (e.g. patients with colonic adenomas, inflammatory polyps, inflammatory bowel disease or HIV infection and in men who have sex with men).

      PubDate: 2017-03-12T17:58:06Z
      DOI: 10.1016/j.anaerobe.2017.03.012
  • Demand-driven biogas production by flexible feeding in full-scale –
           Process stability and flexibility potentials
    • Authors: E. Mauky; S. Weinrich; H.F. Jacobi; H.J. Nägele; J. Liebetrau; M. Nelles
      Abstract: Publication date: Available online 11 March 2017
      Author(s): E. Mauky, S. Weinrich, H.F. Jacobi, H.J. Nägele, J. Liebetrau, M. Nelles
      For future energy supply systems with high proportions from renewable energy sources, biogas plants are a promising option to supply demand-driven electricity to compensate the divergence between energy demand and energy supply by uncontrolled sources like wind and solar. Apart expanding gas storage capacity a demand-oriented feeding with the aim of flexible gas production can be an effective alternative. The presented study demonstrated a high degree of intraday flexibility (up to 50% compared to the average) and a potential for an electricity shutdown of up to 3 days (decreasing gas production by more than 60%) by flexible feeding in full-scale. Furthermore, the long-term process stability was not affected negatively due to the flexible feeding. The flexible feeding resulted in a variable rate of gas production and a dynamic progression of individual acids and the respective pH-value. In consequence, a demand-driven biogas production may enable significant savings in terms of the required gas storage volume (up to 65%) and permit far greater plant flexibility compared to constant gas production.

      PubDate: 2017-03-12T17:58:06Z
      DOI: 10.1016/j.anaerobe.2017.03.010
  • Periprosthetic joint infection by Propionibacterium acnes: Clinical
           differences between monomicrobial versus polymicrobial infection
    • Authors: Raúl Figa; David Muñetón; Lucía Gómez; A. Matamala; Mayli Lung; Eva Cuchi; Pablo S. Corona
      Abstract: Publication date: Available online 8 March 2017
      Author(s): Raúl Figa, David Muñetón, Lucía Gómez, A. Matamala, Mayli Lung, Eva Cuchi, Pablo S. Corona
      Objective To compare a series of monomicrobial Propionibacterium acnes (P. acnes) knee and hip periprosthetic joint infection (PJI) cases with cases of polymicrobial PJI which included P. acnes. We hypothesized that the presence of a polymicrobial P. acnes infection would lead to worse outcomes than those in cases of monomicrobial P. acnes PJI. Methods Retrospective multicentre study. All patients with hip or knee PJIs including P. acnes diagnosed from August-2002 to July-2013 in two university hospitals were included. We collected demographic data, McPherson classification, local signs of infection (swelling or wound drainage), laboratory and histological data, surgical management, antibiotic treatment and outcomes. Data were compared between two groups: cases of monomicrobial P. acnes PJI, and cases of polymicrobial PJI involving P. acnes. Results Thirty-eight patients who presented with 38 PJIs were included; median age was 71 (IQR:62.5–79); 21 were men (55%); median follow-up was 42 months (IQR:17.5–58). Local signs of infection were present in 14 patients (36.8%); ESR>30 mm/h in 14 patients (36.8%); CRP>1 mg/dl in 15 patients (39.5%); 11 out of 25 patients (44%) had positive preoperative cultures from joint aspiration. Positive histologic studies (Feldman's criteria) were found in 5 out of 28 patients (17.8%). Twenty-four patients (63%) had monomicrobial PJIs; 14 patients (37%) had polymicrobial PJIs. There were no significant outcome differences between monomicrobial and polymicrobial PJIs cases; overall, the success rates were 79.2% and 85.7% respectively (P > 0.05). Conclusions We did not find any significant differences between monomicrobial and polymicrobial P. acnes PJI outcomes. ESR, CRP and histologic study are established parameters for diagnosing PJI which did not prove useful in P. acnes PJI.

      PubDate: 2017-03-08T17:44:38Z
      DOI: 10.1016/j.anaerobe.2017.03.008
  • Characterization of isolates of Eisenbergiella tayi, a strictly anaerobic
           Gram-stain variable bacillus recovered from human clinical materials in
    • Authors: Kathryn Bernard; Tamara Burdz; Deborah Wiebe; Brittany M. Balcewich; Tina Zimmerman; Philippe Lagacé-Wiens; Linda M.N. Hoang; Anne-Marie Bernier
      Abstract: Publication date: Available online 7 March 2017
      Author(s): Kathryn Bernard, Tamara Burdz, Deborah Wiebe, Brittany M. Balcewich, Tina Zimmerman, Philippe Lagacé-Wiens, Linda M.N. Hoang, Anne-Marie Bernier
      Eisenbergiella gen. nov. was proposed in 2014 to describe an obligate anaerobic, structurally Gram-positive but Gram-stain-negative-appearing bacillus recovered from the blood culture of an elderly Israeli man. Here, we describe features for eight blood culture isolates as well one appendix-derived isolate, recovered from seven patients located in two Canadian provinces, which by 16S rRNA gene sequencing, were identifiable as Eisenbergiella tayi, the sole validly- named species in this genus. After whole genome sequencing, isolates were found to be essentially identical (96.8–98.7% identity) to each other and to E. tayi DSM 26961T, after comparison using the ANIb tool and in silico DNA-DNA hydridization. All isolates were observed to have remarkably large genomes (7.1–8.3 Mb) with a G + C content of 46.5%–46.9%.

      PubDate: 2017-03-08T17:44:38Z
      DOI: 10.1016/j.anaerobe.2017.03.005
  • First report of human infection by Christensenella minuta, a
           gram-negative, strickly anaerobic rod that inhabits the human intestine
    • Authors: Beatriz Lopez Alonso; Alvaro Irigoyen von Sierakowski; Juan Antonio Sáez Nieto; Antonio Beltran Rosel
      Abstract: Publication date: Available online 7 March 2017
      Author(s): Beatriz Lopez Alonso, Alvaro Irigoyen von Sierakowski, Juan Antonio Sáez Nieto, Antonio Beltran Rosel
      Christensenella minuta is a Gram-negative strictly anaerobic short rod that inhabits the human gut. This bacterium was isolated in a mixed infection with Desulfovibrio desulfuricans from the blood of a patient with a diagnosis of acute appendicitis. The strain was identified by 16S rRNA sequence analysis. As far as we know, this is the first time C.minuta has been isolated from a human clinical specimen.

      PubDate: 2017-03-08T17:44:38Z
      DOI: 10.1016/j.anaerobe.2017.03.007
  • Peritoneal infection due to Peptoniphilus harei in a patient with
           intestinal occlusion
    • Authors: Fernando Cobo; Javier Rodríguez-Granger; Antonio Sampedro; José María Navarro-Marí
      Abstract: Publication date: Available online 7 March 2017
      Author(s): Fernando Cobo, Javier Rodríguez-Granger, Antonio Sampedro, José María Navarro-Marí
      Peptoniphilus harei is a Gram-positive anaerobic coccus mainly involved in polymicrobial infections. We report a case of peritoneal infection in a patient with intestinal occlusion. A 48-year-old woman presented with ascitis after an occlusive syndrome. Culture of peritoneal fluid resulted on P. harei isolation. Treatment was performed and resolution of this infection was documented.

      PubDate: 2017-03-08T17:44:38Z
      DOI: 10.1016/j.anaerobe.2017.03.009
  • Performance of two blood culture systems to detect anaerobic bacteria. Is
           there any difference?
    • Authors: Manica Mueller-Premru; Samo Jeverica; Lea Papst; Elisabeth Nagy
      Abstract: Publication date: Available online 7 March 2017
      Author(s): Manica Mueller-Premru, Samo Jeverica, Lea Papst, Elisabeth Nagy
      We studied the performance characteristics of two blood culture (BC) bottles/systems, (i) BacT/ALERT-FN Plus/3D (bioMérieux, Marcy l’Étoile, France) and (ii) BACTEC-Lytic/9000 (Becton Dickinson, Sparks, USA) for detection of growth and time-to-positivity (TTP) against a balanced and diverse collection of anaerobic bacterial strains (n = 48) that included reference strains (n = 19) and clinical isolates (n = 29) of 32 species (15 Gram-negative and 17 Gram-positive) was tested. Standard suspension of bacteria was inoculated to each bottle in duplicates and incubated in the corresponding system. Overall, 62.5% (n = 30) of strains were detected by both BC bottle types. Comparing the two, 70.8% (n = 34) and 79.2% (n = 38) of strains were detected by BacT/ALERT-FN Plus and BACTEC-Lytic bottles, respectively (p = 0.38). Among Gram-negative anaerobes (n = 25) the detection rate was 76.0% (n = 19) vs. 92.0% (n = 23) (p = 0.22), respectively. Among Gram-positive anaerobes (n = 23) the detection rate was 65.2% (n = 15) in both bottles (p = 1). The average TTP per bottle was calculated only for the strains detected by both systems (n = 30) and was 40.85 h and 28.08 h for BacT/ALERT-FN Plus and BACTEC-Lytic, respectively (p < 0.001). The mean difference was 12.76 h (95% CI: 6.21-19-31 h). Six anaerobic strains were not detected by any system, including Gram-negative Porphyromonas gingivalis, and five Gram-positive strains: Finegoldia magna, Peptostreptococcus anaerobius, Propionibacterium acnes, Clostridium novyi and Clostridium clostridioforme. Furthermore, Eggerthella lenta and Prevotella bivia were detected only by BacT/ALERT-FN Plus, while Prevotella disiens and Prevotella intermedia were detected only by BACTEC-Lytic bottles. Anaerobic bacteria represent a minority of BC isolates, however, far from ideal detection rate was observed in this study for both tested bottle/system combinations. Nevertheless, in those cases where both gave positive signal, BACTEC-Lytic was superior to BacT/ALERT FN Plus with 12.76 h shorter mean TTP.

      PubDate: 2017-03-08T17:44:38Z
      DOI: 10.1016/j.anaerobe.2017.03.006
  • Inhibition of spore germination, growth, and toxin activity of clinically
           relevant C. difficile strains by gut microbiota derived secondary bile
    • Authors: Rajani Thanissery; Jenessa A. Winston; Casey M. Theriot
      Abstract: Publication date: Available online 6 March 2017
      Author(s): Rajani Thanissery, Jenessa A. Winston, Casey M. Theriot
      The changing epidemiology of Clostridium difficile infection over the past decades presents a significant challenge in the management of C. difficile associated diseases. The gastrointestinal tract microbiota provides colonization resistance against C. difficile, and growing evidence suggests that gut microbial derived secondary bile acids (SBAs) play a role. We hypothesized that the C. difficile life cycle; spore germination and outgrowth, growth, and toxin production, of strains that vary by age and ribotype will differ in their sensitivity to SBAs. C. difficile strains R20291 and CD196 (ribotype 027), M68 and CF5 (017), 630 (012), BI9 (001) and M120 (078) were used to define taurocholate (TCA) mediated spore germination and outgrowth, growth, and toxin activity in the absence and presence of gut microbial derived SBAs (deoxycholate, isodeoxycholate, lithocholate, isolithocholate, ursodeoxycholate, ω-muricholate, and hyodeoxycholate) found in the human and mouse large intestine. C. difficile strains varied in their rates of germination, growth kinetics, and toxin activity without the addition of SBAs. C. difficile M120, a highly divergent strain, had robust germination, growth, but significantly lower toxin activity compared to other strains. Many SBAs were able to inhibit TCA mediated spore germination and outgrowth, growth, and toxin activity in a dose dependent manner, but the level of inhibition and resistance varied across all strains and ribotypes. This study illustrates how clinically relevant C. difficile strains can have different responses when exposed to SBAs present in the gastrointestinal tract.

      PubDate: 2017-03-08T17:44:38Z
      DOI: 10.1016/j.anaerobe.2017.03.004
  • Factors associated with Clostridium difficile infection: A nested
           case-control study in a three year prospective cohort
    • Authors: Nagham Khanafer; Philippe Vanhems; Frédéric Barbut; Christine Luxemburger
      Abstract: Publication date: Available online 6 March 2017
      Author(s): Nagham Khanafer, Philippe Vanhems, Frédéric Barbut, Christine Luxemburger
      Background Clostridium difficile infection (CDI) is a serious medical condition that is associated with substantial morbidity and mortality. Identification of risk factors associated with CDI and prompt recognition of patients at risk is key to successfully preventing CDI. Methods A 3-year prospective, observational, cohort study was conducted in a French university hospital and a nested case-control study was performed to identify risk factors for CDI. Inpatients aged 18 years or older, suffering from diarrhea suspected to be related to CDI, were asked to participate. Results A total of 945 patients were included, of which 233 cases had a confirmed CDI. CDI infection was more common in men (58.4%) (P = 0.04) compared with patients with diarrhea not related to C. difficile. Previous hospitalization (P < 0.001), prior treatment with antibiotics (P = 0.001) or antiperistaltics (P = 0.002), liver disease (P = 0.003), malnutrition (P < 0.001), and previous CDI (P < 0.001) were significantly more common in patients with CDI. Multivariate logistic regression analysis showed that exposure to antibiotics in the last 60 days (especially third generation cephalosporins and penicillins with β-lactamase inhibitor), chronic renal or liver disease, malnutrition or previous CDI, were associated with an independent high risk of CDI. Age was not related with CDI. Conclusions This study showed that antibiotics and some comorbid conditions were predictors of CDI. Patients at high risk of acquiring CDI at the time of admission may benefit from careful monitoring of antibiotic prescriptions and early attention to infection control issues. In future, these "high-risk" patients may benefit from novel agents being developed to prevent CDI.

      PubDate: 2017-03-08T17:44:38Z
      DOI: 10.1016/j.anaerobe.2017.03.003
  • Functional gene profiling through metaRNAseq approach reveals
    • Authors: Ankit T. Hinsu; Nidhi R. Parmar; Neelam M. Nathani; Ramesh J. Pandit; Anand B. Patel; Amrutlal K. Patel; Chaitanya G. Joshi
      Abstract: Publication date: Available online 27 February 2017
      Author(s): Ankit T. Hinsu, Nidhi R. Parmar, Neelam M. Nathani, Ramesh J. Pandit, Anand B. Patel, Amrutlal K. Patel, Chaitanya G. Joshi
      Recent advances in next generation sequencing technology have enabled analysis of complex microbial community from genome to transcriptome level. In the present study, metatranscriptomic approach was applied to elucidate functionally active bacteria and their biological processes in rumen of buffalo (Bubalus bubalis) adapted to different dietary treatments. Buffaloes were adapted to a diet containing 50:50, 75:25 and 100:0 forage to concentrate ratio, each for 6 weeks, before ruminal content sample collection. Metatranscriptomes from rumen fiber adherent and fiber-free active bacteria were sequenced using Ion Torrent PGM platform followed by annotation using MG-RAST server and CAZYmes (Carbohydrate active enzymes) analysis toolkit. In all the samples Bacteroidetes was the most abundant phylum followed by Firmicutes. Functional analysis using KEGG Orthology database revealed Metabolism as the most abundant category at level 1 within which Carbohydrate metabolism was dominating. Diet treatments also exerted significant differences in proportion of enzymes involved in metabolic pathways for VFA production. Carbohydrate Active Enzyme(CAZy) analysis revealed the abundance of genes encoding glycoside hydrolases with the highest representation of GH13 CAZy family in all the samples. The findings provide an overview of the activities occurring in the rumen as well as active bacterial population and the changes occurring through different dietary treatments.

      PubDate: 2017-03-03T17:13:07Z
      DOI: 10.1016/j.anaerobe.2017.02.021
  • Early exposure to agricultural soil accelerates the maturation of the
           early-life pig gut microbiota
    • Authors: Vo Nguyen; Tsung Cheng Tsai; Charles Maxwell; Franck Carbonero
      Abstract: Publication date: Available online 27 February 2017
      Author(s): Vo Nguyen, Tsung Cheng Tsai, Charles Maxwell, Franck Carbonero
      Reduced microbial exposure in early childhood is postulated to be associated with subsequent immune deficiencies and associated health conditions. This corollary to the “hygiene hypothesis” has grown of popularity in the medical field, but can only be really tested with animal models. Based on previous observation that access to outdoor environment improves piglets' growth performance, we simulated early microbial exposure by providing pigs with topsoil during the lactation phase. Specifically, pigs from 20 litters were assigned to either control treatments (C) or soil treatments (S): pigs exposed to topsoil from day 4 postpartum to the end of lactation. At weaning, five unisex littermates of 10 sows from each treatment were penned together and grew up in the same conditions. Fecal samples were collected at on d 13 (Lactation: L), 21 (Weaning: WT), 35 (Maintenance, MNT), 56 (End of Nursery: EONT) and 96 (End of Growth: EGT) for 16s rRNA amplicon high-throughput sequencing. Overall, common trends of gut microbiota maturation, associated with diet switch from maternal milk to plant-based diet, were observed. Bacteroides, Clostridium XIVa and Enterobacteriaceae were most abundant during lactation, while Prevotella, Megasphaera and Blautia became abundant after weaning. Remarkably, exposure to soil resulted in a faster maturation of the piglets gut microbiota at weaning, while a completely distinct phase was observed at day 35 for control piglets. Soil-exposed piglets tened to harbor a more diverse gut microbiota at weaning and day35, however the more significant changes were at those time points in terms of composition. Prevotella, and a wide range of Firmicutes members were significantly enriched in soil-exposed piglets from the lactation to the end of nursery phase. It can be hypothesized that those taxa were either directly transmitted from the soil or stimulated by the presence of plant material in the soil. Those changes were accompanied by depletion in several potentially harmful taxa, as well as improved growth performance between weaning and the end of nursery phase. Our findings suggest that early exposure to soil strongly influences the maturation of the early-life piglets, probably allows for a better adaptation to the plant-based diet, and possibly improves overall health.

      PubDate: 2017-03-03T17:13:07Z
      DOI: 10.1016/j.anaerobe.2017.02.022
  • Multilocus sequence typing analyses of Clostridium perfringens type a
           strains harboring tpeL and netB genes
    • Authors: V. Nakano; A. Ignacio; L. Llanco; V. Bueris; M.P. Sircili; M.J. Avila-Campos
      Abstract: Publication date: Available online 24 February 2017
      Author(s): V. Nakano, A. Ignacio, L. Llanco, V. Bueris, M.P. Sircili, M.J. Avila-Campos
      Clostridium perfringens is an anaerobic bacterium ubiquitous in various environments, especially in soil and the gastrointestinal tract of healthy humans and animals. In this study, multilocus sequence typing protocol was used to investigate genotypic relationships among 40 C. perfringens strains isolated from humans and broiler chicken with necrotic enteritis [NE]. The results indicated a few clonal populations, mainly observed in human strains, with 32.5% of all strains associated with one of three clonal complexes and 30 sequences types. The CC-1 cluster showed an interesting and unexpected result because it contained seven strains [six from animals and one of human origin]. Detection assays for toxin genes tpeL and netB were also performed. The netB gene was only observed in 7.5% of the strains from healthy human. The toxin gene tpeL was detected in 22.5% of the C. perfringens strains isolated from three individuals and in six broilers with NE. Our study describes the role of some C. perfringens strains of human origin acting as reservoirs of virulence genes and sources of infection. In addition, the strains of human and animal origin were found to be genetically distinct but phylogenetically close, and the human strains showed more diversity than the animal strains.

      PubDate: 2017-03-03T17:13:07Z
      DOI: 10.1016/j.anaerobe.2017.02.017
  • Bacterial species colonizing the vagina of healthy women are not
           associated with race
    • Authors: May A. Beamer; Michele N. Austin; Hilary A. Avolia; Leslie A. Meyn; Katherine E. Bunge; Sharon L. Hillier
      Abstract: Publication date: Available online 24 February 2017
      Author(s): May A. Beamer, Michele N. Austin, Hilary A. Avolia, Leslie A. Meyn, Katherine E. Bunge, Sharon L. Hillier
      The vaginal microbiota of 36 white versus 25 black asymptomatic women were compared using both cultivation-dependent and -independent identification. Significant differences by race were found in colonization and density of bacterial species. However, exclusion of 12 women with bacterial vaginosis by Nugent criteria resulted in no significant differences by race.

      PubDate: 2017-03-03T17:13:07Z
      DOI: 10.1016/j.anaerobe.2017.02.020
  • Survival of vaginal microorganisms in three commercially available
           transport systems
    • Authors: Allison L. DeMarco; Lorna K. Rabe; Michele N. Austin; Kevin A. Stoner; Hilary A. Avolia; Leslie A. Meyn; Sharon L. Hillier
      Abstract: Publication date: Available online 24 February 2017
      Author(s): Allison L. DeMarco, Lorna K. Rabe, Michele N. Austin, Kevin A. Stoner, Hilary A. Avolia, Leslie A. Meyn, Sharon L. Hillier
      Transport systems are used to collect and maintain the viability of microorganisms. Two Amies media based transport systems, BD CultureSwab™ MaxV(+) Amies Medium without Charcoal (MaxV(+)) and Fisherfinest® with Amies gel Transport Medium without charcoal (Fisherfinest®) were compared to a Cary-Blair media based transport system, Starswab® Anaerobic Transport System (Starswab®), for their capacity to maintain the viability of 17 clinical microorganisms commonly isolated from the vagina (Lactobacillus crispatus, L. jensenii, L. iners, group B streptococci, Candida albicans, Escherichia coli, Enterococcus faecalis, Atopobium vaginae, Peptoniphilus harei, Mycoplasma hominis, Gardnerella vaginalis, Dialister microaerophilus, Mobiluncus curtisii, Prevotella amnii, P. timonensis, P. bivia, and Porphyromonas uenonis). Single swabs containing mixtures of up to five different species were inoculated in triplicate and held at 4 °C and room temperature for 24, 48, 72, and 96 h (h). At each time point, swabs were eluted into a sterile salt solution, serially diluted, inoculated onto selected media, and incubated. Each colony type was quantified and identified. A change in sample stability was reported as a ≥1 log increase or decrease in microorganism density from baseline. Overall, the viability of fastidious anaerobes was maintained better at 4 °C than room temperature. At 4 °C all three transport systems maintained the viability and prevented replication of C. albicans, E. faecalis, GBS, and E. coli. Microorganisms having a ≥1 log decrease in less than 24 h at 4 °C included A. vaginae, G. vaginalis, and P. uenonis in Starswab®, L. iners, A. vaginae, and P. amnii in MaxV(+), and A. vaginae, G. vaginalis, P. bivia, and P. amnii in Fisherfinest®. At 48 h at 4 °C, a ≥1 log decrease in concentration density was observed for P. harei and P. amnii in Starswab®, G. vaginalis, P. bivia and P. uenonis in MaxV(+), and L. iners, P. harei, P. timonensis, and P. uenonis in Fisherfinest®. Overall, at 4 °C the viability and stability of vaginal microorganisms was maintained better in the Cary-Blair based transport system (Starswab®) than in the two Amies based transport systems.

      PubDate: 2017-03-03T17:13:07Z
      DOI: 10.1016/j.anaerobe.2017.02.019
  • Updates on Clostridium difficile spore biology
    • Authors: Fernando Gil; Sebastián Lagos-Moraga; Paulina Calderón-Romero; Marjorie Pizarro-Guajardo; Daniel Paredes-Sabja
      Abstract: Publication date: Available online 22 February 2017
      Author(s): Fernando Gil, Sebastián Lagos-Moraga, Paulina Calderón-Romero, Marjorie Pizarro-Guajardo, Daniel Paredes-Sabja
      Clostridium difficile is a Gram-positive, anaerobic spore former, and an important nosocomial pathogenic bacterium. C. difficile spores are the morphotype of transmission and recurrence of the disease. The formation of C. difficile spores and their subsequent germination are essential processes during the infection. Recent in vitro and in vivo work has shed light on how spores are formed and the timing of in vivo sporulation in a mouse model. Advances have also been made in our understanding of the machineries involved in spore germination, and how antibiotic-induced dysbiosis affects the metabolism of bile salts and thus impacts C. difficile germination in vivo. Studies have also attempted to identify how C. difficile spores interact with the host's intestinal mucosa. Spore resistance has also been revisited by several groups highlighting the extreme resistance of this morphotype to traditional food processing regimes and disinfectants used in clinical settings. Therefore, the aim of this review is to summarize recent advances on spore formation/germination in vitro and in vivo, spore-host interactions, and spore resistance that contribute to our knowledge of the role of C. difficile spores in the infectious process.

      PubDate: 2017-02-23T16:39:25Z
      DOI: 10.1016/j.anaerobe.2017.02.018
  • Influence of nitrogen-rich substrates on biogas production and on the
           methanogenic community under mesophilic and thermophilic conditions
    • Authors: Bernhard Munk; Georg M. Guebitz; Michael Lebuhn
      Abstract: Publication date: Available online 22 February 2017
      Author(s): Bernhard Munk, Georg M. Guebitz, Michael Lebuhn
      Grass silage was evaluated as a possible substrate in anaerobic digestion for generation of biogas in mesophilic and thermophilic long-term operation. Furthermore, the molecular biological parameter Metabolic Quotient (MQ) was evaluated as early warning system to predict process disturbance. Since this substrate is rich in nitrogen, high ammonia concentration of up to 2.2 g * kgFM −1 emerged. The high buffer capacity of the ammonium/ammonia system can disguise upcoming process acidification. At organic loading rates (OLR) below 1.0 kgVS * m−3 * d−1 (VS: volatile solids) for thermophilic and below 1.5 kgVS * m−3 * d−1 for mesophilic reactors, stable processes were established. With increasing OLR, the process was stressed until it broke down in the thermophilic reactors at an OLR of 3.5 kgVS * m−3 * d−1 or was stopped at an OLR of 4.5 kgVS * m−3 * d−1 in the mesophilic reactors. Mainly propionic acid accumulated in concentrations of up to 6.5 g * kgFM −1. Due to the high buffer capacity of the reactor sludge, the chemical parameter TVA/TIC (ratio of total volatile acid to total inorganic carbon) did not clearly indicate process disturbance in advance. In contrast, the MQ indicated metabolic stress of the methanogens before process breakdown and thus showed its potential as early warning system for process breakdown. During the whole experiment, hydrogenotrophic methanogens dominated. In the thermophilic reactors, Methanoculleus IIA-2 sp. 2 and Methanothermobacter wolfeii were dominant during stable process conditions and were displaced by Methanobacterium III sp. 4, a possible new bioindicator for disturbances at these conditions. In the mesophilic reactors, mainly Methanobacterium III sp. 4 was dominant at stable, stressed and acidified processes. A hitherto uncultivated genospecies, Methanobacteriaceae genus IV(B) sp. 3 was determined as possible new bioindicator for mesophilic process disturbance.

      PubDate: 2017-02-23T16:39:25Z
      DOI: 10.1016/j.anaerobe.2017.02.015
  • The first human clinical case of chronic osteomyelitis caused by
           Clostridium hydrogeniformans
    • Authors: Jun Hirai; Daisuke Sakanashi; Ji Young Huh; Hiroyuki Suematsu; Mao Hagihara; Hideo Kato; Yuka Yamagishi; Jiro Fujita; Hiroshige Mikamo
      Abstract: Publication date: Available online 21 February 2017
      Author(s): Jun Hirai, Daisuke Sakanashi, Ji Young Huh, Hiroyuki Suematsu, Mao Hagihara, Hideo Kato, Yuka Yamagishi, Jiro Fujita, Hiroshige Mikamo
      We present the first case report of osteomyelitis due to Clostridium hydrogeniformans in a previously healthy 18-year-old male. He was admitted to our hospital because of an open contaminated fracture of the right arm after being blown into a drain in a motorbike accident. He underwent surgical debridement and treatment course of cefazolin. Although he responded well to these initial treatments, subcutaneous abscess and ulnar osteomyelitis developed 1 month after discharge. Second debridement was performed and specimens were collected from both the abscess and bone tissues. Only anaerobic culture showed a gas-producing Gam-positive rod. Conventional methods and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry could not accurately identify this organism. However, 16S rRNA gene sequence analysis determined the isolate as C. hydrogeniformans with 99.79% homology. The patient recovered after 90 days of antibiotic treatment, and had no evidence of recurrence. Anaerobic bacteria are more common as causative pathogens in osteomyelitis related to traumatic wounds and Clostridium spp. are particularly associated with open fractures, which is consistent with our case. Although the epidemiology and clinical characteristics of C. hydrogeniformans infection is poorly understood because of the limitations of currently available conventional methods of identification, clinicians need to consider this organism as a causative pathogen in a patient with osteomyelitis in traumatic wounds, especially contaminated by sewer water.

      PubDate: 2017-02-23T16:39:25Z
      DOI: 10.1016/j.anaerobe.2017.02.013
  • The fecal microbiome of dogs with exocrine pancreatic insufficiency
    • Authors: Anitha Isaiah; Joseph Cyrus Parambeth; Jörg M. Steiner; Jonathan A. Lidbury; Jan S. Suchodolski
      Abstract: Publication date: Available online 20 February 2017
      Author(s): Anitha Isaiah, Joseph Cyrus Parambeth, Jörg M. Steiner, Jonathan A. Lidbury, Jan S. Suchodolski
      Exocrine pancreatic insufficiency (EPI) in dogs is a syndrome of inadequate synthesis and secretion of pancreatic enzymes. Small intestinal bacterial dysbiosis occurs in dogs with EPI, and is reversed with pancreatic enzyme therapy. However, there are no studies evaluating the fecal microbiome of dogs with EPI. The objective of this study was to evaluate the fecal microbiome of dogs with EPI. Three day pooled fecal samples were collected from healthy dogs (n = 18), untreated (n = 7) dogs with EPI, and dogs with EPI treated with enzyme replacement therapy (n = 19). Extracted DNA from fecal samples was used for Illumina sequencing of the bacterial 16S rRNA gene and analyzed using Quantitative Insights Into Microbial Ecology (QIIME) and PICRUSt was used to predict the functional gene content of the microbiome. Linear discriminant analysis effect size (LEfSe) revealed significant differences in bacterial groups and functional genes between the healthy dogs and dogs with EPI. There was a significant difference in fecal microbial communities when healthy dogs were compared to treated and untreated dogs with EPI (unweighted UniFrac distance, ANOSIM p = 0.001, and 0.001 respectively). Alpha diversity was significantly decreased in untreated and treated EPI dogs when compared to the healthy dogs with respect to Chao1, Observed OTU, and Shannon diversity (p = 0.008, 0.003, and 0.002 respectively). The families Bifidobacteriaceae (p = 0.005), Enterococcaceae (p = 0.018), and Lactobacillaceae (p = 0.001) were significantly increased in the untreated and treated dogs with EPI when compared to healthy dogs. In contrast, Lachnospiraceae (p < 0.001), and Ruminococcaceae (p < 0.01) were significantly decreased in dogs with EPI. Dogs with EPI (before treatment) had significant increases in functional genes associated with secretion system, fatty acid metabolism, and phosphotransferase system. In contrast, healthy dogs had a significant increase in genes related to phenylalanine, tyrosine and tryptophan biosynthesis, transcription machinery and sporulation. In conclusion, this study shows that the fecal microbiome of dogs with EPI (both treated and untreated) is different to that of healthy dogs.

      PubDate: 2017-02-23T16:39:25Z
      DOI: 10.1016/j.anaerobe.2017.02.010
  • Role of the leukocyte response in normal and immunocompromised host after
           Clostridium difficile infection
    • Authors: Edwin Vargas; Senu Apewokin; Rajat Madan
      Abstract: Publication date: Available online 20 February 2017
      Author(s): Edwin Vargas, Senu Apewokin, Rajat Madan
      Clostridium difficile is the leading cause of healthcare-associated infections in the United States. Clinically, C. difficile-associated disease can present as asymptomatic colonization, self-limited diarrheal illness or severe colitis (that may result in death). This variability in disease course and outcomes suggests that host factors play an important role as key determinants of disease severity. Currently, there are several scoring indices to estimate severity of C. difficile-associated disease. Leukocytosis and renal failure are considered to be the most important predictors of C. difficile disease severity in hosts with a normal immune system. The degree of leukocytosis which is considered significant for severe disease and how it is scored vary amongst scoring indices. None of the scores have been prospectively validated, and while total WBC count is useful to estimate the magnitude of the host response in most patient populations, in immune-compromised patients like those receiving chemotherapy, solid organ transplant patients or hematopoietic stem cell transplants the WBC response can be variable or even absent making this marker of severity difficult to interpret. Other cellular subsets like neutrophils, eosinophils and lymphocytes provide important information about the host immune status and play an important role in the immune response against C. difficile infection. However, under the current scoring systems the role of these cellular subsets have been underestimated and only total white blood cell counts are taken into account. In this review we highlight the role of host leukocyte response to C. difficile challenge in the normal and immunocompromised host, and propose possible ways that would allow for a better representation of the different immune cell subsets (neutrophils, lymphocytes and eosinophils) in the current scoring indices.

      PubDate: 2017-02-23T16:39:25Z
      DOI: 10.1016/j.anaerobe.2017.02.014
  • The effect of the source of microorganisms on adaptation of hydrolytic
           consortia dedicated to anaerobic digestion of maize silage
    • Authors: Krzysztof Poszytek; Adam Pyzik; Adam Sobczak; Leszek Lipinski; Aleksandra Sklodowska; Lukasz Drewniak
      Abstract: Publication date: Available online 17 February 2017
      Author(s): Krzysztof Poszytek, Adam Pyzik, Adam Sobczak, Leszek Lipinski, Aleksandra Sklodowska, Lukasz Drewniak
      The main aim of this study was to evaluate the effect of the source of microorganisms on the selection of hydrolytic consortia dedicated to anaerobic digestion of maize silage. The selection process was investigated based on the analysis of changes in the hydrolytic activity and the diversity of microbial communities derived from (i) a hydrolyzer of a commercial agricultural biogas plant, (ii) cattle slurry and (iii) raw sewage sludge, during a series of 10 passages. Following the selection process, the adapted consortia were thoroughly analyzed for their ability to utilize maize silage and augmentation of anaerobic digestion communities. The results of selection of the consortia showed that every subsequent passage of each consortium leads to their adaptation to degradation of maize silage, which was manifested by the increased hydrolytic activity of the adapted consortia. Biodiversity analysis (based on the 16S rDNA amplicon sequencing) confirmed the changes microbial community of each consortium, and showed that after the last (10th) passage all microbial communities were dominated by the representatives of Lactobacillaceae, Prevotellaceae, Veillonellaceae. The results of the functional analyses showed that the adapted consortia improved the efficiency of maize silage degradation, as indicated by the increase in the concentration of glucose and volatile fatty acids (VFAs), as well as the soluble chemical oxygen demand (sCOD). Moreover, bioaugmentation of anaerobic digestion communities by the adapted hydrolytic consortia increased biogas yield by 10–29%, depending on the origin of the community. The obtained results also indicate that substrate input (not community origin) was the driving force responsible for the changes in the community structure of hydrolytic consortia dedicated to anaerobic digestion.

      PubDate: 2017-02-23T16:39:25Z
      DOI: 10.1016/j.anaerobe.2017.02.011
  • A novel archaeal species belonging to Methanoculleus genus identified via
           de-novo assembly and metagenomic binning process in biogas reactors
    • Authors: Panagiotis G. Kougias; Stefano Campanaro; Laura Treu; Xinyu Zhu; Irini Angelidaki
      Abstract: Publication date: Available online 17 February 2017
      Author(s): Panagiotis G. Kougias, Stefano Campanaro, Laura Treu, Xinyu Zhu, Irini Angelidaki
      Recently, a first comprehensive catalogue of microbial genomes populating biogas reactors treating manure and agro-industrial residues was determined by sequencing samples collected from 22 biogas reactors including laboratory and full scale. Among the archaeal community, one of the most abundant methanogens belongs to Methanoculleus genus and for this reason it was provisionally named Methanoculleus sp. DTU006. Its full length 16S rRNA sequence is 97% similar to Methanoculleus marisnigri JR1 and to Methanoculleus palmolei DSM 4273. Despite the high similarity of the 16S gene sequence, Average Nucleotide Identity calculation (ANI) calculated on all protein encoding genes indicated that the two most similar species, Methanoculleus bourgensis MS2T and Methanoculleus sp. MAB1, are divergent enough to define Methanoculleus sp. DTU006 as new archaeal species. Its genome (2.15 Mbp) has an estimated completeness around 93%. Analysis of the metabolic pathways using KEGG confirmed that it is a hydrogenotrophic methanogen and therefore it is proposed the Candidatus status by naming it as “Candidatus Methanoculleus thermohydrogenotrophicum”.

      PubDate: 2017-02-23T16:39:25Z
      DOI: 10.1016/j.anaerobe.2017.02.009
  • Detection of Clostridium perfringens toxin genes in the gut microbiota of
           autistic children
    • Authors: Sydney M. Finegold; Paula H. Summanen; Julia Downes; Karen Corbett; Tomoe Komoriya
      Abstract: Publication date: Available online 17 February 2017
      Author(s): Sydney M. Finegold, Paula H. Summanen, Julia Downes, Karen Corbett, Tomoe Komoriya
      We studied stool specimens from 33 autistic children aged 2–9 years with gastrointestinal (GI) abnormalities and 13 control children without autism and without GI symptoms. We performed quantitative comparison of all Clostridium species and Clostridium perfringens strains from the fecal microbiota by conventional, selective anaerobic culture methods. We isolated C. perfringens strains and performed PCR analysis for the main C. perfringens toxin genes, alpha, beta, beta2, epsilon, iota and C. perfringens enterotoxin gene. Our results indicate that autistic subjects with gastrointestinal disease harbor statistically significantly (p = 0.031) higher counts of C. perfringens in their gut compared to control children. Autistic subjects also harbor statistically significantly (p = 0.015) higher counts of beta2-toxin gene-producing C. perfringens in their gut compared to control children, and the incidence of beta2-toxin gene-producing C. perfringens is significantly higher in autistic subjects compared to control children (p = 0.014). Alpha toxin gene was detected in all C. perfringens strains studied. C. perfringens enterotoxin gene was detected from three autistic and one control subject. Beta, epsilon, and iota toxin genes were not detected from autistic or control subjects.

      PubDate: 2017-02-23T16:39:25Z
      DOI: 10.1016/j.anaerobe.2017.02.008
  • Occurrence of Clostridium difficile ribotype 027 in hospitals of Silesia,
    • Authors: Małgorzata Aptekorz; Anna Szczegielniak; Barbara Wiechuła; Celine Harmanus; Ed Kuijper; Gayane Martirosian
      Abstract: Publication date: Available online 12 February 2017
      Author(s): Małgorzata Aptekorz, Anna Szczegielniak, Barbara Wiechuła, Celine Harmanus, Ed Kuijper, Gayane Martirosian
      Clostridium difficile is an important healthcare-associated pathogen, responsible for a broad spectrum of diarrheal diseases. The aim of this prospective study was to determine the occurrence of C. difficile infection (CDI), to characterize cultured C. difficile strains and to investigate the association of fecal lactoferrin with CDI. Between January 2013 and June 2014, 148 stool samples were obtained from adult diarrheal patients (C. difficile as a suspected pathogen) hospitalized in different healthcare facilities of 15 Silesian hospitals. Out of 134 isolated C. difficile strains, 108 were ribotyped: 82.4% belonged to Type 027, 2.8% to Type 176, 2.8% to Type 014, 1.9% to Type 010 and 0.9% to Types 001, 018, 020 and 046 each. In total, 6.5% non-typable strains were identified. All Type 027 isolates contained both toxin genes tcdA & tcdB, and binary toxin genes (cdtA & cdtB). Susceptibility testing revealed that all Type 027 isolates were sensitive to metronidazole and vancomycin and resistant to moxifloxacin, ciprofloxacin, imipenem and erythromycin. Of 89 Type 027 strains, 16 had a ermB (688 bp) gene coinciding with high levels of erythromycin resistance (MIC >256 μg/mL). Of 16 ermB positive strains, 14 demonstrated also high level of resistance to clindamycin (>256 μg/mL). A significant difference (p = 0.004) in lactoferrin level was found between C. difficile toxin-positive (n = 123; median 185.9 μg/mL; IQR 238.8) and toxin-negative (n = 25; median 22.4 μg/mL; IQR 141.7) fecal samples. Stool samples from n = 89 patients with CDI caused by Type 027 demonstrated significantly higher (p = 0.03) lactoferrin level (median 173.0 μg/mL; IQR 237.3) than from patients with CDI caused by other ribotypes and non-typable C. difficile strains (median 189.4 μg/mL; IQR 190.8).

      PubDate: 2017-02-16T15:57:26Z
      DOI: 10.1016/j.anaerobe.2017.02.002
  • Proteotyping of laboratory-scale biogas plants reveals multiple
           steady-states in community composition
    • Authors: F. Kohrs; R. Heyer; T. Bissinger; R. Kottler; K. Schallert; S. Püttker; A. Behne; E. Rapp; D. Benndorf; U. Reichl
      Abstract: Publication date: Available online 9 February 2017
      Author(s): F. Kohrs, R. Heyer, T. Bissinger, R. Kottler, K. Schallert, S. Püttker, A. Behne, E. Rapp, D. Benndorf, U. Reichl
      Complex microbial communities are the functional core of anaerobic digestion processes taking place in biogas plants (BGP). So far, however, a comprehensive characterization of the microbiomes involved in methane formation is technically challenging. As an alternative, enriched communities from laboratory-scale experiments can be investigated that have a reduced number of organisms and are easier to characterize by state of the art mass spectrometric-based (MS) metaproteomic workflows. Six parallel laboratory digesters were inoculated with sludge from a full-scale BGP to study the development of enriched microbial communities under defined conditions. During the first three month of cultivation, all reactors (R1-R6) were functionally comparable regarding biogas productions (375–625 NL Lreactor volume −1 d−1), methane yields (50–60%), pH values (7.1–7.3), and volatile fatty acids (VFA, <5 mM). Nevertheless, a clear impact of the temperature (R3, R4) and ammonia (R5, R6) shifts were observed for the respective reactors. In both reactors operated under thermophilic regime, acetic and propionic acid (10–20 mM) began to accumulate. While R4 recovered quickly from acidification, the levels of VFA remained to be high in R3 resulting in low pH values of 6.5–6.9. The digesters R5 and R6 operated under the high ammonia regime (>1 gNH3 L−1) showed an increase to pH 7.5–8.0, accumulation of acetate (>10 mM), and decreasing biogas production (<125 NL Lreactor volume −1 d−1). Tandem MS (MS/MS)-based proteotyping allowed the identification of taxonomic abundances and biological processes. Although all reactors showed similar performances, proteotyping and terminal restriction fragment length polymorphisms (T-RFLP) fingerprinting revealed significant differences in the composition of individual microbial communities, indicating multiple steady-states. Furthermore, cellulolytic enzymes and cellulosomal proteins of Clostridium thermocellum were identified to be specific markers for the thermophilic reactors (R3, R4). Metaproteins found in R3 indicated hydrogenothrophic methanogenesis, whereas metaproteins of acetoclastic methanogenesis were identified in R4. This suggests not only an individual evolution of microbial communities even for the case that BGPs are started at the same initial conditions under well controlled environmental conditions, but also a high compositional variance of microbiomes under extreme conditions.
      Graphical abstract image

      PubDate: 2017-02-11T15:44:32Z
      DOI: 10.1016/j.anaerobe.2017.02.005
  • Thermal pretreatment and bioaugmentation improve methane yield of
           microalgal mix produced in thermophilic anaerobic digestate
    • Authors: Lea Lavrič; Ana Cerar; Lijana Fanedl; Borut Lazar; Miha Žitnik; Romana Marinšek Logar
      Abstract: Publication date: Available online 8 February 2017
      Author(s): Lea Lavrič, Ana Cerar, Lijana Fanedl, Borut Lazar, Miha Žitnik, Romana Marinšek Logar
      Liquid fraction produced in anaerobic digestion (AD) of biodegradable waste can be treated on-site with microalgae, which can be recycled back as substrate to the biogas plant. For this research, a pilot high rate algal pond (HRAP) was set with connections to a full scale biogas plant that enabled the use of waste heat and CO2 from a combined heat and power gen-set (CHP). The microalgal mix produced in the thermophilic anaerobic digestate supernatant was tested as a substrate for biogas production in the thermophilic AD (i.e. untreated, bioaugmented with anaerobic bacteria Clostridium thermocellum, and thermally pretreated, respectively). The methane potential of the untreated microalgal mix was low (157.5 ± 18.7 mL CH4/g VS). However, after the thermal pretreatment of the microalgae, methane production increased by 62%, while in the bioaugmentation with C. thermocellum under thermophilic conditions (T = 55 °C) it was elevated by 12%. The outcome of our pilot trial suggests that microalgae produced in the thermophilic biogas digestate represent a prospective alternative AD feedstock. At the same time, microalgae reduce the digestate nitrogen and COD to the level sufficient for the outflow to meet the quality required by the sewage system (ammonia-nitrogen max 200 mg/L, nitrite max 10 mg/L).

      PubDate: 2017-02-11T15:44:32Z
      DOI: 10.1016/j.anaerobe.2017.02.001
  • Association of periodontopathic anaerobic bacterial co-occurrence to
           atherosclerosis-a cross - Sectional study
    • Authors: Krishnan Mahalakshmi; Dr Padma Krishnan; Mylapore Ganesan Krishna Baba; Vaithiyanathan Dhivyapriya; Sarasa Bharathi Arumugam
      Abstract: Publication date: Available online 8 February 2017
      Author(s): Krishnan Mahalakshmi, Dr Padma Krishnan, Mylapore Ganesan Krishna Baba, Vaithiyanathan Dhivyapriya, Sarasa Bharathi Arumugam
      Background Epidemiological studies have shown a link between periodontitis and atherosclerosis. Hence the present study was chosen to assess the presence of eight anaerobic periodontal pathogens and their virulence genes in subgingival plaque (SGP) and atherosclerotic plaque (AP) of patients who underwent Coronary artery bypass graft surgery (CABG). Methods SGP and AP collected from 65 CABG patients were screened for the presence of periodontal bacterial pathogens by Polymerase chain reaction. The samples positive for Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia were screened for virulence genes. Chronic periodontitis patients (ChP) without any systemic disease (n = 59) and healthy subjects free of both periodontitis and systemic disease were included as control groups (n = 100). Results and Discussion Statistical significance was observed for the prevalence of 16S rRNA of P. gingivalis, T. forsythia, T. denticola and P. nigrescens both in SGP and AP. Nine different periodontal bacterial co-occurrences were observed in SGP and AP of CABG patients. Besides, the prevalence of these nine different bacterial co-occurrence was high in SGP OF CABG patients compared to ChP without systemic disease. Among the nine different bacterial co-occurrence, only four were observed in SGP of ChP without systemic disease in spite of high prevalence of these anaerobic bacterial species. While, bacterial co-occurrences was completely absent among healthy subjects. Significant odds and risk ratio to atherosclerosis were observed for P. gingivalis, T. forsythia, T. denticola and P. nigrescens. Among the virulence genes, significance to atherosclerosis was observed for P. gingivalis type II fimA and T. forsythia bspA. Conclusion The results of this study strongly correlate periodontal bacterial co-occurrence and periodontal bacterial adhesion factor to atherosclerosis.

      PubDate: 2017-02-11T15:44:32Z
      DOI: 10.1016/j.anaerobe.2017.02.003
  • Effects of dietary supplementation of active dried yeast on fecal
           methanogenic archaea diversity in dairy cows
    • Authors: Dingxing Jin; Kun Kang; Hongze Wang; Zhisheng Wang; Bai Xue; Lizhi Wang; Feng Xu; Quanhui Peng
      Abstract: Publication date: Available online 7 February 2017
      Author(s): Dingxing Jin, Kun Kang, Hongze Wang, Zhisheng Wang, Bai Xue, Lizhi Wang, Feng Xu, Quanhui Peng
      This study aimed to investigate the effects of dietary supplementation of different dosages of active dried yeast (ADY) on the fecal methanogenic archaea community of dairy cattle. Twelve multiparous, healthy, mid-lactating Holstein dairy cows (body weight: 584 ± 23.2 kg, milk produced: 26.3 ± 1.22 kg/d) were randomly assigned to one of three treatments (control, ADY2, and ADY4) according to body weight with four replicates per treatment. Cows in the control group were fed conventional rations without ADY supplementation, while cows in the ADY2 and ADY4 group were fed rations supplemented with ADY at 2 or 4 g/d/head. Real-time PCR analysis showed the populations of total methanogens in the feces were significantly decreased (P < 0.05) in the ADY4 group compared with control. High-throughput sequencing technology was applied to examine the differences in methanogenic archaea diversity in the feces of the three treatment groups. A total of 155,609 sequences were recovered (a mean of 12,967 sequences per sample) from the twelve fecal samples, which consisted of a number of operational taxonomic units (OTUs) ranging from 1451 to 1,733, were assigned to two phyla, four classes, five orders, five families and six genera. Bioinformatic analyses illustrated that the natural fecal archaeal community of the control group was predominated by Methanobrevibacter (86.9% of the total sequence reads) and Methanocorpusculum (10.4%), while the relative abundance of the remaining four genera were below 1% with Methanosphaera comprising 0.8%, Thermoplasma composing 0.4%, and the relative abundance of Candidatus Nitrososphaera and Halalkalicoccus being close to zero. At the genus level, the relative abundances of Methanocorpusculum and Thermoplasma were increased (P < 0.05) with increasing dosage of ADY. Conversely, the predominant methanogen genus Methanobrevibacter was decreased with ADY dosage (P < 0.05). Dietary supplementation of ADY had no significant effect (P > 0.05) on the abundances of genera unclassified, Candidatus Nitrososphaera, and Halalkalicoccus. In conclusion, supplementation of ADY to the rations of dairy cattle could alter the population sizes and composition of fecal methanogenic archaea in the feces of dairy cattle. The decrease in Methanobrevibacter happened with a commensurate increase in the genera Methanocorpusculum and Thermoplasma.

      PubDate: 2017-02-11T15:44:32Z
      DOI: 10.1016/j.anaerobe.2017.02.007
  • Comparison of Clostridium difficile minimum inhibitory concentrations
           obtained using agar dilution vs broth microdilution methods
    • Authors: Christine J. Hastey; Suzanne E. Dale; Julia Nary; Diane Citron; Jennifer H. Law; Darcie E. Roe-Carpenter; Laurent Chesnel
      Abstract: Publication date: Available online 7 February 2017
      Author(s): Christine J. Hastey, Suzanne E. Dale, Julia Nary, Diane Citron, Jennifer H. Law, Darcie E. Roe-Carpenter, Laurent Chesnel
      Due to increasing antibiotic resistance among anaerobic bacteria, routine antimicrobial susceptibility testing is recommended by the Clinical and Laboratory Standards Institute (CLSI). This study compared the minimum inhibitory concentrations (MICs) from 920 Clostridium difficile isolates tested against seven antimicrobial agents using the two current CLSI reference methodologies, agar dilution method, vs broth microdilution method. A subset of isolate testing was performed independently by two laboratories to evaluate reproducibility. A negative bias was noted for MICs generated from broth microdilution compared to agar dilution and the reproducibility was variable and drug dependent. Therefore, broth microdilution is not recommended as an alternative to agar dilution for C. difficile antimicrobial susceptibility testing.

      PubDate: 2017-02-11T15:44:32Z
      DOI: 10.1016/j.anaerobe.2017.02.006
  • Exposure to β-lactams results in the alteration of penicillin-binding
           proteins in Clostridium perfringens
    • Authors: Miseon Park; Fatemeh Rafii
      Abstract: Publication date: Available online 7 February 2017
      Author(s): Miseon Park, Fatemeh Rafii
      Clostridium perfringens causes a variety of mild to severe infections in humans and other animals. A decrease in the affinity of penicillin-binding protein (PBP) transpeptidases for β-lactams is considered one of the mechanisms of β-lactam resistance in bacteria. Two strains of C. perfringens isolated from bovines and one isolated from a chicken, which had decreased susceptibility to β-lactams, had variations in the amino acid sequences of the central penicillin-binding regions of the PBPs. β-Lactam-resistant mutants of another C. perfringens strain, ATCC 13124, were selected in vitro to determine the effects of exposure to β-lactams on the PBP genes. Cultures of the wild type rapidly developed resistance to penicillin G, cephalothin and ceftriaxone. The susceptibilities of all of the selected mutants to some other β-lactams also decreased. The largest PBP found in C. perfringens, CPF_2395, appeared to be the primary target of all three drugs. Strain resistant to penicillin G had mutation resulting in the substitution of one amino acid within the central penicillin-binding/transpeptidase domain, but the ceftrioxane and cephalothin-resistant strains had mutations resulting in the substitution of two amino acids in this region. The cephalothin-resistant mutant also had additional mutations in the CPF_0340 and CPF_2218 genes in this critical region. No other mutations were observed in the three other PBPs of the in vitro resistant mutants. Resistance development also altered the growth rate and cell morphology of the mutants, so in addition to the PBPs, some other genes, including regulatory genes, may have been affected during the interaction with β-lactam antibiotics. This is the first study showing the effects of β-lactam drugs on the substitution of amino acids in PBPs of C. perfringens and points to the need for studies to detect other unknown alterations affecting the physiology of resistant strains.

      PubDate: 2017-02-11T15:44:32Z
      DOI: 10.1016/j.anaerobe.2017.02.004
  • Dairy propionibacteria prevent the proliferative effect of plant lectins
           on SW480 cells and protect the metabolic activity of the intestinal
           microbiota in vitro
    • Authors: Gabriela Zárate; Gabriel D. Saez; Adriana Pérez chaia
      Abstract: Publication date: Available online 1 February 2017
      Author(s): Gabriela Zárate, Gabriel D. Saez, Adriana Pérez chaia
      Plant lectins are specific carbohydrate-binding proteins that are widespread in legumes such as beans and pulses, seeds, cereals, and many plants used as farm feeds. They are highly resistant to cooking and digestion, reaching the intestinal lumen and/or blood circulation with biological activity. Since many legume lectins trigger harmful local and systemic reactions after their binding to the mucosal surface, these molecules are generally considered anti-nutritive and/or toxic substances. In the gut, specific cell receptors and bacteria may interact with these dietary components, leading to changes in intestinal physiology. It has been proposed that probiotic microorganisms with suitable surface glycosidic moieties could bind to dietary lectins, favoring their elimination from the intestinal lumen or inhibiting their interaction with epithelial cells. In this work, we assessed in vitro the effects of two representative plant lectins, concanavalin A (Con A) and jacalin (AIL) on the proliferation of SW480 colonic adenocarcinoma cells and metabolic activity of colonic microbiota in the absence or presence of Propionibacterium acidipropionici CRL 1198. Both lectins induced proliferation of colonic cells in a dose-dependent manner, whereas ConA inhibited fermentative activities of colonic microbiota. Pre-incubation of propionibacteria with lectins prevented these effects, which could be ascribed to the binding of lectins by bacterial cells since P. acidipropionici CRL 1198 was unable to metabolize these proteins, and its adhesion to colonic cells was reduced after reaction with Con A or AIL. The results suggest that consumption of propionibacteria at the same time as lectins could reduce the incidence of lectin-induced alterations in the gut and may be a tool to protect intestinal physiology.

      PubDate: 2017-02-05T21:42:52Z
      DOI: 10.1016/j.anaerobe.2017.01.012
  • Development of Clostridium difficile R20291ΔPaLoc model strains and in
           vitro methodologies reveals CdtR is required for the production of CDT to
           cytotoxic levels
    • Authors: T.W. Bilverstone; N.L. Kinsmore; N.P. Minton; S.A. Kuehne
      Abstract: Publication date: Available online 17 January 2017
      Author(s): T.W. Bilverstone, N.L. Kinsmore, N.P. Minton, S.A. Kuehne
      Assessing the regulation of Clostridium difficile transferase (CDT), is complicated by the presence of a Pathogenicity locus (PaLoc) which encodes Toxins A and B. Here we developed R20291ΔPaLoc model strains and cell-based assays to quantify CDT-mediated virulence. Their application demonstrated that the transcriptional regulator, CdtR, was required for CDT-mediated cytotoxicity.

      PubDate: 2017-01-22T20:32:01Z
      DOI: 10.1016/j.anaerobe.2017.01.009
  • Diversity of the subspecies Bifidobacterium animalis subsp. lactis
    • Authors: Vera Bunesova; Jiri Killer; Barbora Javurkova; Eva Vlkova; Vaclav Tejnecky; Sarka Musilova; Vojtech Rada
      Abstract: Publication date: Available online 17 January 2017
      Author(s): Vera Bunesova, Jiri Killer, Barbora Javurkova, Eva Vlkova, Vaclav Tejnecky, Sarka Musilova, Vojtech Rada
      Strains of Bifidobacterium animalis subsp. lactis are well-known health-promoting probiotics used commercially. B. animalis subsp. lactis has been isolated from different sources, and little is known about animal isolates of this taxon. The aim of this study was to examine the genotypic and phenotypic diversity between B. animalis subsp. lactis strains different animal hosts including Cameroon sheep, Barbary sheep, okapi, mouflon, German shepard) and to compare to BB12, food isolates and the collection strain DSM 10140. Ten strains of B. animalis subsp. lactis from different sources were characterised by phenotyping, fingerprinting, and multilocus sequence typing (MLST). Regardless of origin, MLST and phylogenetic analyses revealed a close relationship between strains of B. animalis subsp. lactis with commercial and animal origin with the exception of isolates from ovine cheese, mouflon and German Shepard dog. Moreover, isolates from dog and mouflon showed significant differences in fermentation profiles and peptide mass fingerprints (MALDI-TOF). Results indicated phenotypic and genotypic diversity among strains of B. animalis subsp. lactis.

      PubDate: 2017-01-22T20:32:01Z
      DOI: 10.1016/j.anaerobe.2017.01.006
  • Fatal sepsis caused by multidrug-resistant Bacteroides fragilis, harboring
           a cfiA gene and an upstream insertion sequence element, in Japan
    • Authors: Itaru Nakamura; Kotaro Aoki; Yuri Miura; Tetsuo Yamaguchi; Tetsuya Matsumoto
      Abstract: Publication date: Available online 17 January 2017
      Author(s): Itaru Nakamura, Kotaro Aoki, Yuri Miura, Tetsuo Yamaguchi, Tetsuya Matsumoto
      Here, we report a case of fatal sepsis resulting from an intra-abdominal infection caused by a Bacteroides fragilis strain containing a CfiA4 metallo-β-lactamase and an upstream insertion sequence (IS) element. Meropenem was used as empiric therapy for septic shock as a result of the intra-abdominal infection, although two rounds of carbapenem treatment had been administered previously. B. fragilis was isolated from two anaerobic blood culture bottles 4 days after the onset of septic shock. Susceptibility testing revealed that the isolate was non-susceptible to all tested agents except metronidazole and tigecycline. The isolate gave a positive result in ethylenediaminetetraacetic acid and carbapenem inactivation tests, but a negative result in a double-disk synergy test using sodium mercaptoacetate. Next-generation whole-genome sequencing indicated the presence of the cfiA4, emrG and emrF genes. PCR indicated the presence of an IS element upstream of the cifA4 gene. Although carbapenem-resistant B. fragilis isolates have previously been reported, clinical sepsis by this organism is considered rare. In Japan, as in most countries worldwide, routine susceptibility testing and the detection of metallo-β-lactamases is not carried out in anaerobic organisms, including B. fragilis. The emergence of carbapenem resistance during therapy should be monitored, as B. fragilis strains containing the cfiA gene show decreased sensitivity during carbapenem therapy. Therefore, susceptibility testing and appropriate antibiotic stewardship are required in cases of anaerobic bacterial infections.

      PubDate: 2017-01-22T20:32:01Z
      DOI: 10.1016/j.anaerobe.2017.01.010
  • A case of pyometrocolpos with Bifidobacterium species
    • Authors: Maanasa M. Bhaskar; Sujatha Sistla; S. Kumaravel
      Abstract: Publication date: Available online 17 January 2017
      Author(s): Maanasa M. Bhaskar, Sujatha Sistla, S. Kumaravel
      Bifidobacterium species, a normal commensal of the human gastrointestinal tract, female genitourinary tract and vagina is usually considered non-pathogenic and is being used therapeutically as probiotic due to its beneficial effects. However, there are several case reports implicating Bifidobacteria as the causative agent in various infectious conditions. Infections with Bifidobacteria are often ignored or underreported as they are part of the normal gut microbiome. Here we discuss a case of pyometrocolpos with Bifidobacterium species. Clinical outcome of the patient was good after emergency drainage and antibiotic treatment with Cefoperazone sulbactam and Metronidazole.

      PubDate: 2017-01-22T20:32:01Z
      DOI: 10.1016/j.anaerobe.2017.01.007
  • The role of gut microbiota in health and disease: In vitro modeling of
           host-microbe interactions at the aerobe-anaerobe interphase of the human
    • Authors: Julius Z.H. von Martels; Mehdi Sadaghian Sadabad; Arno R. Bourgonje; Tjasso Blokzijl; Gerard Dijkstra; Klaas Nico Faber; Hermie J.M. Harmsen
      Abstract: Publication date: Available online 3 January 2017
      Author(s): Julius Z.H. von Martels, Mehdi Sadaghian Sadabad, Arno R. Bourgonje, Tjasso Blokzijl, Gerard Dijkstra, Klaas Nico Faber, Hermie J.M. Harmsen
      The microbiota of the gut has many crucial functions in human health. Dysbiosis of the microbiota has been correlated to a large and still increasing number of diseases. Recent studies have mostly focused on analyzing the associations between disease and an aberrant microbiota composition. Functional studies using (in vitro) gut models are required to investigate the precise interactions that occur between specific bacteria (or bacterial mixtures) and gut epithelial cells. As most gut bacteria are obligate or facultative anaerobes, studying their effect on oxygen-requiring human gut epithelial cells is technically challenging. Still, several (anaerobic) bacterial-epithelial co-culture systems have recently been developed that mimic host-microbe interactions occurring in the human gut, including 1) the Transwell “apical anaerobic model of the intestinal epithelial barrier”, 2) the Host-Microbiota Interaction (HMI) module, 3) the “Human oxygen-Bacteria anaerobic” (HoxBan) system, 4) the human gut-on-a-chip and 5) the HuMiX model. This review discusses the role of gut microbiota in health and disease and gives an overview of the characteristics and applications of these novel host-microbe co-culture systems.

      PubDate: 2017-01-07T16:33:42Z
      DOI: 10.1016/j.anaerobe.2017.01.001
  • Fatal community-acquired ribotype 002 Clostridium difficile bacteremia
    • Authors: Nicolas Dauby; Agnès Libois; Johan van Broeck; Michel Delmée; Olivier Vandenberg; Delphine Martiny
      Abstract: Publication date: Available online 30 December 2016
      Author(s): Nicolas Dauby, Agnès Libois, Johan van Broeck, Michel Delmée, Olivier Vandenberg, Delphine Martiny
      Extra-colonic infections, and especially bacteremia, are infrequent manifestations of Clostridium difficile infection. C. difficile bacteremia is generally health-care associated and polymicrobial. We report the case of a patient on hunger strike that presented a C. difficile colitis and mono-microbial bacteremia on its admission to the hospital. Multilocus variable number tandem repeat analysis of stool and blood isolates indicated clonality. The strain was characterized as a ribotype 002, an emerging ribotype previously associated with high fatality rate. The patient received treatment by intra-venous amoxicillin-clavulanate and oral vancomycin but eventually died on the seventh day of admission with concomitant pneumonia and pulmonary embolism.

      PubDate: 2017-01-07T16:33:42Z
      DOI: 10.1016/j.anaerobe.2016.12.013
  • First Robinsoniella peoriensis aortic cross homograft mycotic
           pseudoaneurysm: A case report and review of the literature
    • Authors: H. Mertes; L. Defourny; M. Tré-Hardy; R. Lhommel; G. El Khoury; H. Rodriguez-Villalobos; L. Belkhir
      Abstract: Publication date: Available online 30 December 2016
      Author(s): H. Mertes, L. Defourny, M. Tré-Hardy, R. Lhommel, G. El Khoury, H. Rodriguez-Villalobos, L. Belkhir
      Mycotic aortic aneurysm is a rare and challenging complication of aortic homografts caused by an infection and is associated with high morbidity and mortality. We report the first case of an aortic cross homograft mycotic pseudoaneurysm caused by Robinsoniella peoriensis in a 70-year-old man. Our patient underwent surgery for a recurrence of aortic cross mycotic pseudoaneurysm at the level of the aortic homograft he had had 7 years before. A clot-removal of the pseudoaneurysm was surgically carried out and the homograft was completely removed. Anaerobic culture from tissue samples yielded pure growth of a spore-forming Gram-positive rod, identified later as Robinsoniella peoriensis by 16S rRNA gene sequencing. The patient was then discharged with oral clindamycin according to the in vitro susceptibility testing. Identification of R. peoriensis might be challenging in clinical laboratories with no access to molecular methods.

      PubDate: 2017-01-07T16:33:42Z
      DOI: 10.1016/j.anaerobe.2016.12.014
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