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  Subjects -> BIOLOGY (Total: 2974 journals)
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    - BIOLOGY (1421 journals)
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BIOLOGY (1421 journals)            First | 1 2 3 4 5 6 7 8 | Last

Showing 801 - 1000 of 1720 Journals sorted alphabetically
Journal of Genomes and Exomes     Open Access  
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: 11)
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: 12)
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: 16)
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: 9)
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: 1)
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: 21)
Journal of Vinyl & Additive Technology     Hybrid Journal  
Journal of Virological Methods     Hybrid Journal   (Followers: 6)
Journal of Virology     Hybrid Journal   (Followers: 30)
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: 5)
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: 58)
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: 29)
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: 12)
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: 107)
Molecular Biology International     Open Access   (Followers: 2)
Molecular Biology of the Cell     Partially Free   (Followers: 20)
Molecular Biology Reports     Hybrid Journal   (Followers: 4)

  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  [3039 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
           gingivalis
    • 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)
       
  • Occurrence of Clostridium difficile ribotype 027 in hospitals of Silesia,
           Poland
    • Authors: Małgorzata Aptekorz; Anna Szczegielniak; Barbara Wiechuła; Celine Harmanus; Ed Kuijper; Gayane Martirosian
      Abstract: Publication date: Available online 12 February 2017
      Source:Anaerobe
      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
      Source:Anaerobe
      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
      Source:Anaerobe
      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
      Source:Anaerobe
      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
      Source:Anaerobe
      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
      Source:Anaerobe
      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
      Source:Anaerobe
      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
      Source:Anaerobe
      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
      Source:Anaerobe
      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
      Source:Anaerobe
      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
      Source:Anaerobe
      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
      Source:Anaerobe
      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
       
  • Simple biogas desulfurization by microaeration – Full scale
           experience
    • Authors: Bindzar
      Abstract: Publication date: Available online 5 January 2017
      Source:Anaerobe
      Author(s): P. Jeníček, J. Horejš, L. Pokorná-Krayzelová, J. Bindzar, J. Bartáček
      Hydrogen sulfide in biogas is common problem during anaerobic treatment of wastewater with high sulfate concentration (breweries, distilleries, etc.) and needs to be removed before biogas utilization. Physico-chemical desulfurization methods are energetically demanding and expensive compare to biochemical methods. Microaeration, i.e. dosing of small amount of air, is suitable and cost effective biochemical method of sulfide oxidation to elemental sulfur. It has been widely used in biogas plants, but its application in anaerobic reactors for wastewater treatment has been rarely studied or tested. The lack of full-scale experience with microaeration in wastewater treatment plants has been overcome by evaluating the results of seven microaerobic digesters in central Europe. The desulfurization efficiency has been more than 90% in most of the cases. Moreover, microaeration improved the degradability of COD and volatile suspended solids.
      Graphical abstract image

      PubDate: 2017-01-07T16:33:42Z
       
  • Characterization of the planktonic microbiome in upflow anaerobic sludge
           blanket reactors during adaptation of mesophilic methanogenic granules to
           thermophilic operational conditions
    • Authors: Xinyu Zhu; Laura Treu; Panagiotis G. Kougias; Stefano Campanaro; Irini Angelidaki
      Abstract: Publication date: Available online 3 January 2017
      Source:Anaerobe
      Author(s): Xinyu Zhu, Laura Treu, Panagiotis G. Kougias, Stefano Campanaro, Irini Angelidaki
      Upflow anaerobic sludge blanket (UASB) technology refers to reactor technology where granules, i.e. self-immobilised microbial associations, are the biological catalysts involved in the anaerobic digestion process. During the start-up period, UASB reactors operate at relatively long HRT and therefore the liquid phase of the reactor becomes a favourable environment for microbial growth. The current study aimed to elucidate the dynamicity of the suspended microbial community in UASB reactors, during the transition from mesophilic to thermophilic conditions. High throughput 16S rRNA amplicon sequencing was used to characterize the taxonomic composition of the microbiome. The results showed that the microbial community was mainly composed by hydrolytic and fermentative bacteria. Results revealed relevant shifts in the microbial community composition, which is mainly determined by the operational conditions and the reactor performance. Finally, shared OTUs between the microbial consortia of the suspended and the granular sludge showed that planktonic microbiota is significantly influencing the granule microbial community composition.

      PubDate: 2017-01-07T16:33:42Z
      DOI: 10.1016/j.anaerobe.2016.12.015
       
  • The role of gut microbiota in health and disease: In vitro modeling of
           host-microbe interactions at the aerobe-anaerobe interphase of the human
           gut
    • 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
      Source:Anaerobe
      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
      Source:Anaerobe
      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
      Source:Anaerobe
      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
       
  • Pomegranate ellagitannins stimulate the growth of Akkermansia muciniphila
           in vivo
    • Authors: Susanne M. Henning; Paula H. Summanen; Ru-Po Lee; Jieping Yang; Sydney M. Finegold; David Heber; Zhaoping Li
      Pages: 56 - 60
      Abstract: Publication date: February 2017
      Source:Anaerobe, Volume 43
      Author(s): Susanne M. Henning, Paula H. Summanen, Ru-Po Lee, Jieping Yang, Sydney M. Finegold, David Heber, Zhaoping Li
      Results from our previous human pomegranate extract (POM extract) intervention study demonstrated that about seventy percent of participants were able to form urolithin A from ellagitannins in the intestine (urolithin A producers). Urolithin A formation was associated with a high proportion of Akkermansia muciniphila in fecal bacterial samples as determined by 16S rRNA sequencing. Here we investigated whether A. muciniphila counts increased in stool samples collected after the POM extract intervention compared to baseline stool samples using real-time PCR. In addition, we performed in vitro culture studies to determine the effect of POM extract and ellagic acid on the growth of A. muciniphila and to analyze ellagic acid metabolites formed in the culture broth by high-performance liquid chromatography. Supplementation of culture broth with 10 μM of ellagic acid did not change A. muciniphila growth while the addition of 0.18 mg/ml and 0.28 mg/ml of POM extract to the culture broth inhibited the growth of A. muciniphila significantly. Incubation of A. muciniphila with POM extract resulted in formation of ellagic acid and incubation of A. muciniphila with ellagic acid demonstrated hydrolysis of ellagic acid to metabolites different from urolithin A. The in vitro culture studies with A. muciniphila partially explain our in vivo findings that the presence of A. muciniphila was associated with breakdown of ellagic acid for further metabolism by other members of the microbiota. This is the first report of the role of A. muciniphila in ellagitannin hydrolysis. However, we conclude that enzymes from other bacteria must be involved in the formation of urolithin A in the human intestine.

      PubDate: 2016-12-14T14:41:22Z
      DOI: 10.1016/j.anaerobe.2016.12.003
      Issue No: Vol. 43 (2016)
       
  • Clinical characteristics and antimicrobial susceptibilities of anaerobic
           bacteremia in an acute care hospital
    • Authors: Thean Yen Tan; Lily Siew Yong Ng; Lee Ling Kwang; Suma Rao; Li Ching Eng
      Pages: 69 - 74
      Abstract: Publication date: February 2017
      Source:Anaerobe, Volume 43
      Author(s): Thean Yen Tan, Lily Siew Yong Ng, Lee Ling Kwang, Suma Rao, Li Ching Eng
      This study investigated the clinical features of anaerobic bacteraemia in an acute-care hospital, and evaluated the antimicrobial susceptibility of these isolates to commonly available antibiotics. Microbiological and epidemiological data from 2009 to 2011were extracted from the laboratory information system and electronic medical records. One hundred and eleven unique patient episodes consisting of 116 anaerobic isolates were selected for clinical review and antibiotic susceptibility testing. Susceptibilities to amoxicillin-clavulanate, clindamycin, imipenem, metronidazole, moxifloxacin, penicillin and piperacillin-tazobactam were performed using Etest strips with categorical interpretations according to current CLSI breakpoints. Metronidazole-resistant and carbapenem-resistant anaerobic Gram-negative bacilli were screened for the nim and cfiA genes. Clinical data was obtained retrospectively from electronic medical records. During the 3 year period, Bacteroides fragilis group (41%), Clostridium species (14%), Propionibacterium species (9%) and Fusobacterium species (6%) were the most commonly isolated anaerobes. Patients with anaerobic bacteraemia that were included in the study were predominantly above 60 years of age, with community-acquired infections. The most commonly used empiric antibiotic therapies were beta-lactam/beta-lactamase inhibitor combinations (44%) and metronidazole (10%). The crude mortality was 25%, and appropriate initial antibiotic therapy was not significantly associated with improved survival. Intra-abdominal infections (39%) and soft-tissue infections (33%) accounted for nearly three-quarters of all bacteraemia. Antibiotics with the best anaerobic activity were imipenem, piperacillin-tazobactam, amoxicillin-clavulanate and metronidazole, with in-vitro susceptibility rates of 95%, 95%, 94% and 92% respectively. Susceptibilities to penicillin (31%), clindamycin (60%) and moxifloxacin (84%) were more variable. Two multidrug-resistant isolates of Bacteroides species were positive for nim and cfiA genes respectively, while another two imipenem-resistant Fusobacterium species were negative for cfiA genes. This study demonstrated that anaerobic bacteraemia in our patient population was predominantly associated with intra-abdominal and soft-tissue infections. Overall antibiotic resistance was high for penicillin and clindamycin, and the presence of emerging resistance to carbapenems and metronidazole warrants further monitoring.

      PubDate: 2016-12-22T15:20:54Z
      DOI: 10.1016/j.anaerobe.2016.11.009
      Issue No: Vol. 43 (2016)
       
  • Clinical characteristics and antimicrobial susceptibilities of anaerobic
           bacteremia in an acute care hospital
    • Authors: Thean Yen Tan; Lily Siew Yong Ng; Lee Ling Kwang; Suma Rao; Li Ching Eng
      Pages: 69 - 74
      Abstract: Publication date: February 2017
      Source:Anaerobe, Volume 43
      Author(s): Thean Yen Tan, Lily Siew Yong Ng, Lee Ling Kwang, Suma Rao, Li Ching Eng
      This study investigated the clinical features of anaerobic bacteraemia in an acute-care hospital, and evaluated the antimicrobial susceptibility of these isolates to commonly available antibiotics. Microbiological and epidemiological data from 2009 to 2011were extracted from the laboratory information system and electronic medical records. One hundred and eleven unique patient episodes consisting of 116 anaerobic isolates were selected for clinical review and antibiotic susceptibility testing. Susceptibilities to amoxicillin-clavulanate, clindamycin, imipenem, metronidazole, moxifloxacin, penicillin and piperacillin-tazobactam were performed using Etest strips with categorical interpretations according to current CLSI breakpoints. Metronidazole-resistant and carbapenem-resistant anaerobic Gram-negative bacilli were screened for the nim and cfiA genes. Clinical data was obtained retrospectively from electronic medical records. During the 3 year period, Bacteroides fragilis group (41%), Clostridium species (14%), Propionibacterium species (9%) and Fusobacterium species (6%) were the most commonly isolated anaerobes. Patients with anaerobic bacteraemia that were included in the study were predominantly above 60 years of age, with community-acquired infections. The most commonly used empiric antibiotic therapies were beta-lactam/beta-lactamase inhibitor combinations (44%) and metronidazole (10%). The crude mortality was 25%, and appropriate initial antibiotic therapy was not significantly associated with improved survival. Intra-abdominal infections (39%) and soft-tissue infections (33%) accounted for nearly three-quarters of all bacteraemia. Antibiotics with the best anaerobic activity were imipenem, piperacillin-tazobactam, amoxicillin-clavulanate and metronidazole, with in-vitro susceptibility rates of 95%, 95%, 94% and 92% respectively. Susceptibilities to penicillin (31%), clindamycin (60%) and moxifloxacin (84%) were more variable. Two multidrug-resistant isolates of Bacteroides species were positive for nim and cfiA genes respectively, while another two imipenem-resistant Fusobacterium species were negative for cfiA genes. This study demonstrated that anaerobic bacteraemia in our patient population was predominantly associated with intra-abdominal and soft-tissue infections. Overall antibiotic resistance was high for penicillin and clindamycin, and the presence of emerging resistance to carbapenems and metronidazole warrants further monitoring.

      PubDate: 2016-12-22T15:20:54Z
      DOI: 10.1016/j.anaerobe.2016.11.009
      Issue No: Vol. 43 (2016)
       
  • Effects of corn silage and grass silage in ruminant rations on diurnal
           changes of microbial populations in the rumen of dairy cows
    • Authors: Melanie B. Lengowski; Maren Witzig; Jens Möhring; Gero M. Seyfang; Markus Rodehutscord
      Pages: 6 - 16
      Abstract: Publication date: Available online 20 July 2016
      Source:Anaerobe
      Author(s): Melanie B. Lengowski, Maren Witzig, Jens Möhring, Gero M. Seyfang, Markus Rodehutscord
      Here, we examined diurnal changes in the ruminal microbial community and fermentation characteristics of dairy cows fed total mixed rations containing either corn silage (CS) or grass silage (GS) as forage. The rations, which consisted of 52% concentrate and 48% GS or CS, were offered for ad libitum intake over 20 days to three ruminal-fistulated lactating Jersey cows during three consecutive feeding periods. Feed intake, ruminal pH, concentrations of short chain fatty acids and ammonia in rumen liquid, as well as abundance change in the microbial populations in liquid and solid fractions, were monitored in 4-h intervals on days 18 and 20. The abundance of total bacteria and Fibrobacter succinogenes increased in solids in cows fed CS instead of GS, and that of protozoa increased in both solid and liquid fractions. Feeding GS favored numbers of F. succinogenes and Selenomonas ruminantium in the liquid fraction as well as the numbers of Ruminobacter amylophilus, Prevotella bryantii and ruminococci in both fractions. Minor effects of silage were detected on populations of methanogens. Despite quantitative changes in the composition of the microbial community, fermentation characteristics were less affected by forage source. These results suggest a functional adaptability of the ruminal microbiota to total mixed rations containing either GS or CS as the source of forage. Diurnal changes in microbial populations were primarily affected by feed intake and differed between species and fractions, with fewer temporal fluctuations evident in the solid than in the liquid fraction. Interactions between forage source and sampling time were of minor importance to most of the microbial species examined. Thus, diurnal changes of microbial populations and fermentative activity were less affected by the two silages.

      PubDate: 2016-07-24T11:57:37Z
      DOI: 10.1016/j.anaerobe.2016.07.004
      Issue No: Vol. 42 (2016)
       
  • Analysis of the rumen bacterial diversity of goats during shift from
           forage to concentrate diet
    • Authors: Diego Javier Grilli; Kateřina Fliegerová; Jan Kopečný; Sebastián Paez Lama; Vanina Egea; Noelia Sohaefer; Celia Pereyra; María Soledad Ruiz; Miguel Angel Sosa; Graciela Nora Arenas; Jakub Mrázek
      Pages: 17 - 26
      Abstract: Publication date: Available online 12 July 2016
      Source:Anaerobe
      Author(s): Diego Javier Grilli, Kateřina Fliegerová, Jan Kopečný, Sebastián Paez Lama, Vanina Egea, Noelia Sohaefer, Celia Pereyra, María Soledad Ruiz, Miguel Angel Sosa, Graciela Nora Arenas, Jakub Mrázek
      High-grain feeding used in the animal production is known to affect the host rumen bacterial community, but our understanding of consequent changes in goats is limited. This study was therefore aimed to evaluate bacterial population dynamics during 20 days adaptation of 4 ruminally cannulated goats to the high-grain diet (grain: hay – ratio of 40:60). The dietary transition of goats from the forage to the high-grain-diet resulted in the significant decrease of rumen fluid pH, which was however still higher than value established for acute or subacute ruminal acidosis was not diagnosed in studied animals. DGGE analysis demonstrated distinct ruminal microbial populations in hay-fed and grain-fed animals, but the substantial animal-to-animal variation were detected. Quantitative PCR showed for grain-fed animals significantly higher number of bacteria belonging to C. leptum group at 10 days after the incorporation of corn into the diet and significantly lower concentration of bacteria belonging to Actinobacteria phylum at the day 20 after dietary change. Taxonomic distribution analysed by NGS at day 20 revealed the similar prevalence of the phyla Firmicutes and Bacteroidetes in all goats, significantly higher presence of the unclassified genus of groups of Bacteroidales and Ruminococcaceae in grain-fed animals and significantly higher presence the genus Prevotella and Butyrivibrio in the forage-fed animals. The three different culture-independent methods used in this study show that high proportion of concentrate in goat diet does not induce any serious disturbance of their rumen ecosystem and indicate the good adaptive response of caprine ruminal bacteria to incorporation of corn into the diet.

      PubDate: 2016-07-24T11:57:37Z
      DOI: 10.1016/j.anaerobe.2016.07.002
      Issue No: Vol. 42 (2016)
       
  • Counterselection employing mutated pheS for markerless genetic deletion in
           Bacteroides species
    • Authors: Yasuhiro Kino; Haruyuki Nakayama-Imaohji; Masashi Fujita; Ayano Tada; Saori Yoneda; Kazuya Murakami; Masahito Hashimoto; Tetsuya Hayashi; Katsuichiro Okazaki; Tomomi Kuwahara
      Pages: 81 - 88
      Abstract: Publication date: December 2016
      Source:Anaerobe, Volume 42
      Author(s): Yasuhiro Kino, Haruyuki Nakayama-Imaohji, Masashi Fujita, Ayano Tada, Saori Yoneda, Kazuya Murakami, Masahito Hashimoto, Tetsuya Hayashi, Katsuichiro Okazaki, Tomomi Kuwahara
      Markerless gene deletion is necessary for multiple gene disruptions due to the limited number of antibiotic resistant markers for some bacteria. However, even in transformable strains, obtaining the expected mutation without a marker requires laborious screening of a large number of colonies. Previous studies had success in various bacteria with a counter-selection system where a conditional lethal gene was incorporated into the vector. We examined the efficacy of the mutated pheS gene (pheS*) as a counter-selective marker for gene deletion in Bacteroides. This mutation produces an amino acid substitution (A303G) in the alpha subunit of Bacteroides phenylalanyl tRNA synthetase, which in E. coli alters the specificity of the tRNA synthetase resulting in a conditional lethal mutation due to the incorporation of p-chloro-phenylalanine (p-Cl-Phe) into protein. B. fragilis YCH46 and B. thetaiotaomicron VPI-5482 transformed with a pheS*-harboring shuttle vector were clearly growth-inhibited in the presence of >5 mM p-Cl-Phe in liquid defined minimal media (DMM) and on DMM agar plates. A targeting plasmid was constructed to delete the genetic region for capsular polysaccharide PS2 in B. fragilis or PS1 in B. thetaiotaomicron. After counterselection, p-Cl-Phe-resistant colonies were generated at a frequency of 8.1 × 10−3 for B. fragilis and 1.7 × 10−3 for B. thetaiotaomicron. Of the p-Cl-Phe-resistant colonies, 4.2% and 72% harbored the correct genetic deletion for B. fragilis and B. thetaiotaomicron, respectively. These results indicate that mutated pheS is a useful counter-selective gene to construct markerless genetic deletions in Bacteroides.

      PubDate: 2016-12-07T14:21:36Z
      DOI: 10.1016/j.anaerobe.2016.09.004
      Issue No: Vol. 42 (2016)
       
  • Fusobacterium necrophorum tonsillitis with mild case of Lemierre's
           syndrome
    • Authors: Pavan Kumar; Panchavati Bhavini Kar Ali Hassoun Robert Centor
      Abstract: Publication date: Available online 28 December 2016
      Source:Anaerobe
      Author(s): Pavan Kumar Panchavati, Bhavini Kar, Ali Hassoun, Robert M. Centor


      PubDate: 2016-12-29T16:01:25Z
       
  • Detection of Fusobacterium nucleatum in two cases of empyema and lung
           abscess using paromomycin-vancomycin supplemented Brucella HK agar
    • Authors: Kentaro Nagaoka; Katsunori Yanagihara; Yosuke Harada; Koichi Yamada; Yohei Migiyama; Yoshitomo Morinaga; Koichi Izumikawa; Shigeru Kohno
      Abstract: Publication date: Available online 26 December 2016
      Source:Anaerobe
      Author(s): Kentaro Nagaoka, Katsunori Yanagihara, Yoshitomo Morinaga, Shigeru Kohno
      Fusobacterium nucleatum was found in patients with empyema or pulmonary abscess, using paromomycin-vancomycin Brucella HK agar. In vitro examination revealed that growth of the strains differed significantly in different media. Clinicians should be aware that suboptimal F. nucleatum cultivation methods may result in an underestimation of its frequency.

      PubDate: 2016-12-29T16:01:25Z
      DOI: 10.1016/j.jiac.2016.09.013
       
  • First report of metronidazole resistant, nimD-positive, Bacteroides
           stercoris isolated from an abdominal abscess in a 70-year-old woman
    • Authors: Erik Otte; Hans Linde Nielsen; Henrik Hasman; David Fuglsang-Damgaard
      Abstract: Publication date: Available online 21 December 2016
      Source:Anaerobe
      Author(s): Erik Otte, Hans Linde Nielsen, Henrik Hasman, David Fuglsang-Damgaard
      We here present the first case of a metronidazole resistant nimD positive Bacteroides stercoris. The isolate originated from a polymicrobial intra-abdominal abscess in a 70-year-old woman. The nimD gene was detected by use of whole-genome shotgun sequencing and the subsequent use of the ResFinder 2.1 web service.

      PubDate: 2016-12-22T15:20:54Z
      DOI: 10.1016/j.anaerobe.2016.12.010
       
  • First report of metronidazole resistant, nimD-positive, Bacteroides
           stercoris isolated from an abdominal abscess in a 70-year-old woman
    • Authors: Erik Otte; Hans Linde Nielsen; Henrik Hasman; David Fuglsang-Damgaard
      Abstract: Publication date: Available online 21 December 2016
      Source:Anaerobe
      Author(s): Erik Otte, Hans Linde Nielsen, Henrik Hasman, David Fuglsang-Damgaard
      We here present the first case of a metronidazole resistant nimD positive Bacteroides stercoris. The isolate originated from a polymicrobial intra-abdominal abscess in a 70-year-old woman. The nimD gene was detected by use of whole-genome shotgun sequencing and the subsequent use of the ResFinder 2.1 web service.

      PubDate: 2016-12-22T15:20:54Z
      DOI: 10.1016/j.anaerobe.2016.12.010
       
  • Probiotics and prevention of Clostridium difficile infection
    • Authors: E.J.C. Goldstein; S.J. Johnson; P.-J. Maziade; C.T. Evans; J.C. Sniffen; M. Millette; L.V. McFarland
      Abstract: Publication date: Available online 14 December 2016
      Source:Anaerobe
      Author(s): E.J.C. Goldstein, S.J. Johnson, P.-J. Maziade, C.T. Evans, J.C. Sniffen, M. Millette, L.V. McFarland
      The role of probiotics as adjunctive measures in the prevention of Clostridium difficile infection (CDI) has been controversial. However, a growing body of evidence has suggested that they have a role in primary prevention of CDI. Elements of this controversy are reviewed and the proposed mechanisms of action, the value and cost effectiveness of probiotics are addressed with a focus on three agents, Saccharomyces boulardii, Lactobacillus rhamnosus GG and the combination of Lactobacillus acidophilus CL1285, Lactobacillus casei LBC80R, Lactobacillus rhamnosus CLR2 (Bio-K+).

      PubDate: 2016-12-22T15:20:54Z
      DOI: 10.1016/j.anaerobe.2016.12.007
       
  • Probiotics and prevention of Clostridium difficile infection
    • Authors: E.J.C. Goldstein; S.J. Johnson; P.-J. Maziade; C.T. Evans; J.C. Sniffen; M. Millette; L.V. McFarland
      Abstract: Publication date: Available online 14 December 2016
      Source:Anaerobe
      Author(s): E.J.C. Goldstein, S.J. Johnson, P.-J. Maziade, C.T. Evans, J.C. Sniffen, M. Millette, L.V. McFarland
      The role of probiotics as adjunctive measures in the prevention of Clostridium difficile infection (CDI) has been controversial. However, a growing body of evidence has suggested that they have a role in primary prevention of CDI. Elements of this controversy are reviewed and the proposed mechanisms of action, the value and cost effectiveness of probiotics are addressed with a focus on three agents, Saccharomyces boulardii, Lactobacillus rhamnosus GG and the combination of Lactobacillus acidophilus CL1285, Lactobacillus casei LBC80R, Lactobacillus rhamnosus CLR2 (Bio-K+).

      PubDate: 2016-12-22T15:20:54Z
      DOI: 10.1016/j.anaerobe.2016.12.007
       
  • Low antibiotic resistance among anaerobic Gram-negative bacteria in
           periodontitis 5 years following metronidazole therapy
    • Authors: G. Dahlen; H. Preus
      Abstract: Publication date: Available online 14 December 2016
      Source:Anaerobe
      Author(s): G. Dahlen, H. Preus
      The objective of this study was to assess antibiotic susceptibility among predominant Gram-negative anaerobic bacteria isolated from periodontitis patients who 5 years prior had been subject to mechanical therapy with or without adjunctive metronidazole. One pooled sample was taken from the 5 deepest sites of each of 161 patients that completed the 5 year follow-up after therapy. The samples were analyzed by culture. A total number of 85 anaerobic strains were isolated from the predominant subgingival flora of 65/161 patient samples, identified, and tested for antibiotic susceptibility by MIC determination. E-tests against metronidazole, penicillin, amoxicillin, amoxicillin + clavulanic acid and clindamycin were employed. The 73/85 strains were Gram-negative rods (21 Porphyromonas spp., 22 Prevotella/Bacteroides spp., 23 Fusobacterium/Filifactor spp., 3 Campylobacter spp. and 4 Tannerella forsythia). These were all isolated from the treated patients irrespective of therapy procedures (+/−metronidazole) 5 years prior. Three strains (Bifidobacterium spp., Propionibacterium propionicum, Parvimonas micra) showed MIC values for metronidazole over the European Committee on Antimicrobial Susceptibility Testing break point of >4 μg/mL. All Porphyromonas and Tannerella strains were highly susceptible. Metronidazole resistant Gram-negative strains were not found, while a few showed resistance against beta-lactam antibiotics. In this population of 161 patients who had been subject to mechanical periodontal therapy with or without adjunct metronidazole 5 years prior, no cultivable antibiotic resistant anaerobes were found in the predominant subgingival microbiota.

      PubDate: 2016-12-14T14:41:22Z
      DOI: 10.1016/j.anaerobe.2016.12.009
       
  • Isolation of Clostridium difficile from dogs with digestive disorders,
           including stable metronidazole-resistant strains
    • Authors: Cristina Orden; Jose L. Blanco; Sergio Álvarez-Pérez; Mercedes Garcia-Sancho; Fernando Rodriguez-Franco; Angel Sainz; Alejandra Villaescusa; Celine Harmanus; Ed Kuijper; Marta E. Garcia
      Abstract: Publication date: Available online 11 December 2016
      Source:Anaerobe
      Author(s): Cristina Orden, Jose L. Blanco, Sergio Álvarez-Pérez, Mercedes Garcia-Sancho, Fernando Rodriguez-Franco, Angel Sainz, Alejandra Villaescusa, Celine Harmanus, Ed Kuijper, Marta E. Garcia
      The prevalence of Clostridium difficile in 107 dogs with diverse digestive disorders attended in a Spanish veterinary teaching hospital was assessed. The microorganism was isolated from 13 dogs (12.1%) of different disease groups. Isolates belonged to PCR ribotypes 078, 106, 154 and 430 (all of them toxigenic) and 110 (non-toxigenic), and were resistant to several antimicrobial drugs. Notably, seven isolates obtained from different dogs displayed stable resistance to metronidazole. The results of this study provide further evidence that dogs can act as a reservoir of C. difficile strains of epidemic ribotypes with resistance to multiple antibiotics.

      PubDate: 2016-12-14T14:41:22Z
      DOI: 10.1016/j.anaerobe.2016.12.008
       
  • SigCH, an extracytoplasmic function sigma factor of Porphyromonas
           gingivalis regulates the expression of cdhR and hmuYR
    • Authors: Koki Ota; Yuichiro Kikuchi; Kentaro Imamura; Daichi Kita; Kouki Yoshikawa; Atsushi Saito; Kazuyuki Ishihara
      Abstract: Publication date: Available online 8 December 2016
      Source:Anaerobe
      Author(s): Koki Ota, Yuichiro Kikuchi, Kentaro Imamura, Daichi Kita, Kouki Yoshikawa, Atsushi Saito, Kazuyuki Ishihara
      Extracytoplasmic function (ECF) sigma factors play an important role in the bacterial response to various environmental stresses. Porphyromonas gingivalis, a prominent etiological agent in human periodontitis, possesses six putative ECF sigma factors. So far, information is limited on the ECF sigma factor, PGN_0319. The aim of this study was to investigate the role of PGN_0319 (SigCH) of P. gingivalis, focusing on the regulation of hmuY and hmuR, which encode outer-membrane proteins involved in hemin utilization, and cdhR, a transcriptional regulator of hmuYR. First, we evaluated the gene expression profile of the sigCH mutant by DNA microarray. Among the genes with altered expression levels, those involved in hemin utilization were downregulated in the sigCH mutant. To verify the microarray data, quantitative reverse transcription PCR analysis was performed. The RNA samples used were obtained from bacterial cells grown to early-log phase, in which sigCH expression in the wild type was significantly higher than that in mid-log and late-log phases. The expression levels of hmuY, hmuR, and cdhR were significantly decreased in the sigCH mutant compared to wild type. Transcription of these genes was restored in a sigCH complemented strain. Compared to the wild type, the sigCH mutant showed reduced growth in log phase under hemin-limiting conditions. Electrophoretic mobility shift assays showed that recombinant SigCH protein bound to the promoter region of hmuY and cdhR. These results suggest that SigCH plays an important role in the early growth of P. gingivalis, and directly regulates cdhR and hmuYR, thereby playing a potential role in the mechanisms of hemin utilization by P. gingivalis.

      PubDate: 2016-12-14T14:41:22Z
      DOI: 10.1016/j.anaerobe.2016.12.006
       
  • Recurrent obstructive acute pyelonephritis: A rare form of Actinobaculum
           schaalii infection in a HIV-1 infected patient
    • Authors: Anaïs Vallet; Nicolas Noël; Rachid Bahi; Elina Teicher; Yann Quertainmont; Jean-François Delfraissy; Sophie Ferlicot; Anaïs Potron; Cécile Goujard; Olivier Lambotte
      Abstract: Publication date: Available online 8 December 2016
      Source:Anaerobe
      Author(s): Anaïs Vallet, Nicolas Noël, Rachid Bahi, Elina Teicher, Yann Quertainmont, Jean-François Delfraissy, Sophie Ferlicot, Anaïs Potron, Cécile Goujard, Olivier Lambotte
      Actinobaculum schaalii is a rarely reported, anaerobic, Gram-positive bacterium which role as uropathogen is emerging. We report here the case of a 47 year old HIV-1 infected woman presented with five recurrent episodes of obstructive pyelonephritis in the context of multiple renal stones. No bacteria was found until the fifth episode, during which prolonged urinary cultures as well as 16S rDNA sequencing allowed the diagnosis of A. schaalii infection. She had developed a life-threatening condition with severe renal failure. A right nephrectomy was performed and found that the intrarenal stones were attributed to the antiretroviral therapy. The renal parenchyma corresponded to an end-stage renal disease with chronic pyelonephritis without abcesses or granules. The situation improved after six months of amoxicillin therapy.

      PubDate: 2016-12-14T14:41:22Z
      DOI: 10.1016/j.anaerobe.2016.12.004
       
  • Improving the energy balance of grass-based anaerobic digestion through
           combined harvesting and pretreatment
    • Authors: P. Tsapekos; P.G. Kougias; H. Egelund; U. Larsen; J. Pedersen; P. Trénel; I. Angelidaki
      Abstract: Publication date: Available online 8 December 2016
      Source:Anaerobe
      Author(s): P. Tsapekos, P.G. Kougias, H. Egelund, U. Larsen, J. Pedersen, P. Trénel, I. Angelidaki
      An important challenge that has to be addressed to achieve sustainable anaerobic digestion of lignocellulosic substrates is the development of energy and cost efficient pretreatment methods. Technologies orientated to simultaneously harvest and mechanically pretreat the biomass at the field could meet these criteria as they can potentially reduce the energy losses. The objective of this study was to elucidate the effect of two full-scale harvesting machines to enhance the biogas production and subsequently, improve energy balance. The performances of Disc-mower and Excoriator were assessed on meadow and cultivated grass silages. The results showed that relatively high methane production can be achieved from meadow and cultivated grass harvested in different seasons. The findings indicated that the bioenergy production can be improved based on the selection of the appropriate harvesting technology. More specifically, Excoriator, which cuts and subsequently applies shearing forces on harvested biomass, enhanced the methane production up to 10% and the overall energy budget was improved proportionally to the driving speed increase.

      PubDate: 2016-12-14T14:41:22Z
      DOI: 10.1016/j.anaerobe.2016.12.005
       
  • Blautia massiliensis sp. nov., isolated from a fresh human fecal sample
           and emended description of the genus Blautia
    • Authors: Guillaume A. Durand; Thao Pham; Sokhna Ndongo; Sory Traore; Grégory Dubourg; Jean-Christophe Lagier; Caroline Michelle; Nicholas Armstrong; Pierre-Edouard Fournier; Didier Raoult; Matthieu Million
      Abstract: Publication date: Available online 5 December 2016
      Source:Anaerobe
      Author(s): Guillaume A. Durand, Thao Pham, Sokhna Ndongo, Sory Traore, Grégory Dubourg, Jean-Christophe Lagier, Caroline Michelle, Nicholas Armstrong, Pierre-Edouard Fournier, Didier Raoult, Matthieu Million
      The strain GD9T is the type strain of the newly proposed species Blautia massiliensis sp. nov., belonging to the family Lachnospiraceae. It was isolated from a fresh stool sample collected from a healthy human using the culturomics strategy. Cells are Gram-negative rods, oxygen intolerant, non-motile and non-spore forming. The 16S rRNA gene sequencing showed that strain GD9T was closely related to Blautia luti, with a 97.8% sequence similarity. Major fatty acids were C14:0 (19.8%) and C16:0 (53.2%). Strain GD9T exhibits a genome of 3,717,339 bp that contains 3346 protein-coding genes and 81 RNAs genes including 63 tRNAs. The features of this organism are described here, with its complete genome sequence and annotation. Compared with other Blautia species which are Gram positive, the strain was Gram negative justifying an emended description of the genus Blautia.

      PubDate: 2016-12-07T14:21:36Z
      DOI: 10.1016/j.anaerobe.2016.12.001
       
  • Rhodomyrtone inhibits lipase production, biofilm formation, and
           disorganizes established biofilm in Propionibacterium acnes
    • Authors: Suttiwan Wunnoo; Jongkon Saising; Supayang Piyawan Voravuthikunchai
      Abstract: Publication date: Available online 5 December 2016
      Source:Anaerobe
      Author(s): Suttiwan Wunnoo, Jongkon Saising, Supayang Piyawan Voravuthikunchai
      Virulence enzymes and biofilm a play crucial role in the pathogenesis of Propionibacterium acnes, a major causative agent of acne vulgaris. In the present study, the effects of rhodomyrtone, a pure compound identified from Rhodomyrtus tomentosa (Aiton) Hassk. leaves extract against enzyme production and biofilm formation production by 5 clinical isolates and a reference strain were evaluated. The degree of hydrolysis by both lipase and protease enzymes significantly decreased upon treatment with the compound at 0.125–0.25 μg/mL (p < 0.05). Lipolytic zones significantly reduced in all isolates while decrease in proteolytic activities was found only in 50% of the isolates. Rhodomyrtone at 1/16MIC and 1/8MIC caused significant reduction in biofilm formation of the clinical isolates (p < 0.05). Percentage viability of P. acnes within mature biofilm upon treated with the compound at 4MIC and 8MIC ranged between 40% and 85%. Pronounced properties of rhodomyrtone suggest a path towards developing a novel anti-acne agent.

      PubDate: 2016-12-07T14:21:36Z
      DOI: 10.1016/j.anaerobe.2016.12.002
       
  • Actinotignum schaalii subcutaneous abscesses in a patient with
           hidradenitis suppurativa: Case report and literature review
    • Authors: Sofia Maraki; George Evangelou; Dimitra Stafylaki; Efstathia Scoulica
      Abstract: Publication date: Available online 29 November 2016
      Source:Anaerobe
      Author(s): Sofia Maraki, George Evangelou, Dimitra Stafylaki, Efstathia Scoulica
      Actinotignum schaalii (formerly Actinobaculum schaalii) is a Gram-positive, facultative anaerobic rod that is typically involved in urinary tract infections in elderly patients or those with underlying urological pathologies. In contrast, abscess formation caused by A. schaalii is very rare. We present a case of multiple abscesses in the perineal area in a young patient with hidradenitis suppurativa associated with A. schaalii and Prevotella melaninogenica and review the relevant literature on the topic.

      PubDate: 2016-11-30T13:33:38Z
      DOI: 10.1016/j.anaerobe.2016.11.010
       
  • Rapid identification of Robinsoniella peoriensis using specific 16S rRNA
           gene PCR primers
    • Authors: Terence R. Whitehead; Christelle Anoma; Richard W. McLaughlin
      Abstract: Publication date: Available online 24 November 2016
      Source:Anaerobe
      Author(s): Terence R. Whitehead, Christelle Anoma, Richard W. McLaughlin
      Robinsoniella peoriensis is a Gram-positive, spore-forming anaerobic bacterium initially isolated and characterized from swine manure and feces. Since then strains of this species have been identified from a variety of mammalian and other GI tracts. More recently strains of this species have been isolated from a plethora of human infections. Therefore, it is of great interest to develop methods to rapidly identify this microorganism in the medical and other laboratories. This report describes the use of PCR primers targeting the 16S rRNA gene of R. peoriensis to identify strains of this bacterium.

      PubDate: 2016-11-30T13:33:38Z
      DOI: 10.1016/j.anaerobe.2016.11.008
       
  • Isolation of a sulfide-producing bacterial consortium from cooling-tower
           water: Evaluation of corrosive effects on galvanized steel
    • Authors: Esra Ilhan-Sungur; Derya Ozuolmez; Ayşın Çotuk; Nurhan Cansever; Gerard Muyzer
      Abstract: Publication date: Available online 18 November 2016
      Source:Anaerobe
      Author(s): Esra Ilhan-Sungur, Derya Ozuolmez, Ayşın Çotuk, Nurhan Cansever, Gerard Muyzer
      Sulfidogenic Clostridia and sulfate reducing bacteria (SRB) often cohabit in nature. The presence of these microorganisms can cause microbially influenced corrosion (MIC) of materials in different ways. To investigate this aspect, bacteria were isolated from cooling tower water and used in corrosion tests of galvanized steel. The identity of the isolates was determined by comparative sequence analysis of PCR-amplified 16S rDNA gene fragments, separated by denaturing gradient gel electrophoresis (DGGE). This analysis showed that, in spite of the isolation process, colonies were not pure and consisted of a mixture of bacteria affiliated with Desulfosporosinus meridiei and Clostridium sp. To evaluate the corrosive effect, galvanized steel coupons were incubated with a mixed culture for 4, 8, 24, 72, 96, 168, 360 and 744 h, along with a control set in sterile culture medium only. The corrosion rate was determined by weight loss, and biofilm formation and corroded surfaces were observed by scanning electron microscopy (SEM). Although the sulfide-producing bacterial consortium led to a slight increase in the corrosion of galvanized steel coupons, when compared to the previous studies it can be said that Clostridium sp. can reduce the corrosive effect of the Desulfosporosinus sp. strain.

      PubDate: 2016-11-23T20:38:35Z
      DOI: 10.1016/j.anaerobe.2016.11.005
       
  • Survival and prevalence of Clostridium difficile in manure compost derived
           from pigs
    • Authors: Masaru Usui; Mayuko Kawakura; Nobuki Yoshizawa; Lai Lai San; Chie Nakajima; Yasuhiko Suzuki; Yutaka Tamura
      Abstract: Publication date: Available online 18 November 2016
      Source:Anaerobe
      Author(s): Masaru Usui, Mayuko Kawakura, Nobuki Yoshizawa, Lai Lai San, Chie Nakajima, Yasuhiko Suzuki, Yutaka Tamura
      Pigs, particularly piglets, have been identified as reservoir hosts of Clostridium difficile. To examine the survival ability of this pathogen in pig feces-based manure compost, C. difficile spores, which were prepared to contain as few vegetative cells as possible, were artificially inoculated into pig feces and incubated at different temperatures. While C. difficile survived in the feces incubated at temperatures below 37 °C for over 30 days, cell numbers gradually decreased at thermophilic temperatures (over 55 °C; p < 0.05). Next, to clarify the prevalence of C. difficile in field manure compost, we isolated and characterized C. difficile from the final products of manure compost products of 14 pig farms. A total of 11 C. difficile strains were isolated from 5 of 14 (36% positive rate) samples tested. Of these 11 strains, 82% were toxigenic, with ribotype 078 being the most prevalent. Thus, the application of composted manure to land therefore poses a possible risk of C. difficile transfer to the food chain.

      PubDate: 2016-11-23T20:38:35Z
      DOI: 10.1016/j.anaerobe.2016.11.004
       
  • Trends in antimicrobial resistance among Bacteroides species and
           Parabacteroides species in the United States from 2010–2012 with
           comparison to 2008–2009
    • Authors: D.R. Snydman; N.V. Jacobus; L.A. McDermott; E.J.C. Goldstein; L. Harrell; S.G. Jenkins; D. Newton; R. Patel; D.W. Hecht
      Abstract: Publication date: Available online 17 November 2016
      Source:Anaerobe
      Author(s): D.R. Snydman, N.V. Jacobus, L.A. McDermott, E.J.C. Goldstein, L. Harrell, S.G. Jenkins, D. Newton, R. Patel, D.W. Hecht
      The susceptibility trends for Bacteroides fragilis and related species against various antibiotics were determined using data from 3 years of surveillance (2010–2012) on 779 isolates referred by 7 medical centers. The antibiotic test panel included imipenem, ertapenem, meropenem, ampicillin-sulbactam, piperacillin-tazobactam, cefoxitin, clindamycin, moxifloxacin, tigecycline, linezolid, chloramphenicol and . MICs were determined using the agar dilution CLSI reference method. Carbapenem resistance remained low (range 1.1%–2.5%) and unchanged from 2008 to 9 through 2010–2012. Resistance also remained low to the beta-lactam/beta-lactamase inhibitor combinations (1.1%–4.4%). While resistance to clindamycin and moxifloxacin remained high; rates were lower for B. fragilis in 2010-12 (24% and 19% respectively) compared to the earlier time frame of 2008-9 (29% and 35% respectively for the earlier time frame). There were notable species and resistance associations which have been demonstrated previously. No resistance to metronidazole or chloramphenicol resistance was seen. These data demonstrate the continued variability in resistance among Bacteroides and Parabacteroides species, but do demonstrate that carbapenems and beta-lactam/beta-lactamase inhibitor combinations remain very active throughout the United States.

      PubDate: 2016-11-23T20:38:35Z
      DOI: 10.1016/j.anaerobe.2016.11.003
       
  • Isolation and molecular characterization of Clostridium perfringens from
           healthy Merino lambs in Patagonia region, Argentina
    • Authors: A.C. Mignaqui; R.B. Marcellino; T. Ronco; J.S. Pappalardo; B. Nonnemann; K. Pedersen; C.A. Robles
      Abstract: Publication date: Available online 12 November 2016
      Source:Anaerobe
      Author(s): A.C. Mignaqui, R.B. Marcellino, T. Ronco, J.S. Pappalardo, B. Nonnemann, K. Pedersen, C.A. Robles
      The presence and molecular characterization of Clostridium perfringens in healthy Merino lambs over a six-month period was investigated in this study. Overall, a high prevalence of C. perfringens was detected, even in day-old lambs. Even though the majority of the isolates were characterized as being of type A, types C and D were also isolated. Furthermore, a high genetic diversity was observed by PFGE among the type A isolates.

      PubDate: 2016-11-16T19:48:55Z
      DOI: 10.1016/j.anaerobe.2016.10.015
       
  • Establishment and development of the intestinal microbiota of preterm
           infants in a Lebanese tertiary hospital
    • Authors: Tarek Itani; Carole Ayoub Moubareck; Imad Melki; Clotilde Rousseau; Irène Mangin; Marie-José Butel; Dolla Karam Sarkis
      Abstract: Publication date: Available online 8 November 2016
      Source:Anaerobe
      Author(s): Tarek Itani, Carole Ayoub Moubareck, Imad Melki, Clotilde Rousseau, Irène Mangin, Marie-José Butel, Dolla Karam Sarkis
      The establishment and development of the intestinal microbiota is known to be associated with profound short- and long-term effects on the health of full-term infants (FTI), but studies are just starting for preterm infants (PTI). The data also mostly come from western countries and little information is available for the Middle East. Here, we determined the composition and dynamics of the intestinal microbiota during the first month of life for PTI (n = 66) and FTI (n = 17) in Lebanon. Fecal samples were collected weekly and analyzed by quantitative PCR (q-PCR) and temporal temperature gradient gel electrophoresis (TTGE). We observed differences in the establishment and composition of the intestinal microbiota between the two groups. q-PCR showed that PTI were more highly colonized by Staphylococcus than FTI in the first three weeks of life; whereas FTI were more highly colonized by Clostridium clusters I and XI. At one month of life, PTI were mainly colonized by facultative anaerobes and a few strict anaerobes, such as Clostridium cluster I and Bifidobacterium. The type of feeding and antibiotic treatments significantly affected intestinal colonization. TTGE revealed low species diversity in both groups and high inter-individual variability in PTI. Our findings show that PTI had altered intestinal colonization with a higher occurrence of potential pathogens (Enterobacter, Clostridium sp) than FTI. This suggests the need for intervention strategies for PTI to modulate their intestinal microbiota and promote their health.

      PubDate: 2016-11-09T19:29:18Z
      DOI: 10.1016/j.anaerobe.2016.11.001
       
  • The effect of quercetin on genetic expression of the commensal gut
           microbes Bifidobacterium catenulatum, Enterococcus caccae and Ruminococcus
           gauvreauii
    • Authors: Jenni Firrman; LinShu Liu; Liqing Zhang; Gustavo Arango Argoty; Minqian Wang; Peggy Tomasula; Masuko Kobori; Sherri Pontious; Weidong Xiao
      Abstract: Publication date: Available online 11 October 2016
      Source:Anaerobe
      Author(s): Jenni Firrman, LinShu Liu, Liqing Zhang, Gustavo Arango Argoty, Minqian Wang, Peggy Tomasula, Masuko Kobori, Sherri Pontious, Weidong Xiao
      Quercetin is one of the most abundant polyphenols found in fruits and vegetables. The ability of the gut microbiota to metabolize quercetin has been previously documented; however, the effect that quercetin may have on commensal gut microbes remains unclear. In the present study, the effects of quercetin on the commensal gut microbes Ruminococcus gauvreauii, Bifidobacterium catenulatum and Enterococcus caccae were determined through evaluation of growth patterns and cell morphology, and analysis of genetic expression profiles between quercetin treated and non-treated groups using Single Molecule RNA sequencing via Helicos technology. Results of this study revealed that phenotypically, quercetin did not prevent growth of Ruminococcus gauvreauii, mildly suppressed growth of Bifidobacterium catenulatum, and moderately inhibited growth of Enterococcus caccae. Genetic analysis revealed that in response to quercetin, Ruminococcus gauvreauii down regulated genes responsible for protein folding, purine synthesis and metabolism. Bifidobacterium catenulatum increased expression of the ABC transport pathway and decreased metabolic pathways and cell wall synthesis. Enterococcus caccae upregulated genes responsible for energy production and metabolism, and downregulated pathways of stress response, translation and sugar transport. For the first time, the effect of quercetin on the growth and genetic expression of three different commensal gut bacteria was documented. The data provides insight into the interactions between genetic regulation and growth. This is also a unique demonstration of how RNA single molecule sequencing can be used to study the gut microbiota.

      PubDate: 2016-10-13T17:09:25Z
      DOI: 10.1016/j.anaerobe.2016.10.004
       
  • Transcriptomic analysis of Propionibacterium acnes biofilms in vitro
    • Authors: Anika C. Jahns; Hinnerk Eilers; Oleg A. Alexeyev
      Abstract: Publication date: Available online 7 October 2016
      Source:Anaerobe
      Author(s): Anika C. Jahns, Hinnerk Eilers, Oleg A. Alexeyev
      Propionibacterium acnes is a well-known commensal of the human skin connected to acne vulgaris and joint infections. It is extensively studied in planktonic cultures in the laboratory settings but occurs naturally in biofilms. In this study we have developed an in vitro biofilm model of P. acnes and studied growth features, matrix composition, matrix penetration by fluorescent-labelled antibiotics as well as gene expression. Antibiotic susceptibility of biofilms was studied and could be enhanced by increased glucose concentrations. Biofilm cells were characterized by up-regulated stress-induced genes and up-regulation of genes coding for the potential virulence-associated CAMP factors. P. acnes can generate persister cells showing a reversible tolerance to 50 fold MIC of common antibiotics.

      PubDate: 2016-10-13T17:09:25Z
      DOI: 10.1016/j.anaerobe.2016.10.001
       
  • The unappreciated in vitro activity of tedizolid against Bacteroides
           fragilis species, including strains resistant to metronidazole and
           carbapenems
    • Authors: Ellie J.C. Goldstein; Diane M. Citron; Kerin L. Tyrrell; Elisa Leoncio; C. Vreni Merriam
      Abstract: Publication date: Available online 3 October 2016
      Source:Anaerobe
      Author(s): Ellie J.C. Goldstein, Diane M. Citron, Kerin L. Tyrrell, Elisa Leoncio, C. Vreni Merriam
      The comparative in vitro activity of tedizolid against 124 Bacteroides group species isolates, including carbapenem, metronidazole and piperacillin-tazobactam resistant strains, had an MIC90 of 2 μg/ml (range, 0.5–4 μg/ml) and was 1–4 times more active than linezolid that had an MIC90 of 8 μg/ml (range, 2–16 μg/ml).

      PubDate: 2016-10-06T16:39:29Z
      DOI: 10.1016/j.anaerobe.2016.09.008
       
 
 
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