BACKGROUND: The rumen microbiota is one of the most complex consortia of anaerobes, involving archaea, bacteria, protozoa, fungi and phages. They are very effective at utilizing plant polysaccharides, especially cellulose and hemicelluloses. The most important hemicellulose decomposers are clustered with the genus Butyrivibrio. As the related species differ in their range of hydrolytic activities and substrate preferences, Butyrivibrio fibrisolvens was selected as one of the most effective isolates and thus suitable for proteomic studies on substrate comparisons in the extracellular fraction. The B. fibrisolvens genome is the biggest in the butyrivibria cluster and is focused on "environmental information processing" and "carbohydrate metabolism". METHODS: The study of the effect of carbon source on B. fibrisolvens 3071 was based on cultures grown on four substrates: xylose, glucose, xylan, xylan with 25% glucose. The enzymatic activities were studied by spectrophotometric and zymogram methods. Proteomic study was based on genomics, 2D electrophoresis and nLC/MS (Bruker Daltonics) analysis. RESULTS: Extracellular β-endoxylanase as well as xylan β-xylosidase activities were induced with xylan. The presence of the xylan polymer induced hemicellulolytic enzymes and increased the protein fraction in the interval from 40 to 80 kDa. 2D electrophoresis with nLC/MS analysis of extracellular B. fibrisolvens 3071 proteins found 14 diverse proteins with significantly different expression on the tested substrates. CONCLUSION: The comparison of four carbon sources resulted in the main significant changes in B. fibrisolvens proteome occurring outside the fibrolytic cluster of proteins. The affected proteins mainly belonged to the glycolysis and protein synthesis cluster.

• Klíčová slova
• Butyrivibrio fibrisolvens, Carbon sources, Proteomics, Rumen,
• Publikační typ
• časopisecké články MeSH

Genes encoding glycosyl hydrolase family 11 (GH11) xylanases and xylanases have been identified from Pseudobutyrivibrio xylanivorans. In contrast, little is known about the diversity and distribution of the GH10 xylanase in strains of P. xylanivorans. Xylanase and associated activities of P. xylanivorans have been characterized in detail in the type strain, Mz5. The aim of the present study was to identify GH10 xylanase genes in strains 2 and Mz5 of P. xylanivorans. In addition, we evaluated degradation and utilization of xylan by P. xylanivorans 2 isolated from rumen of Creole goats. After a 12-h culture, P. xylanivorans 2 was able to utilize up to 53% of the total pentose content present in birchwood xylan (BWX) and to utilize up to 62% of a ethanol-acetic acid-soluble fraction prepared from BWX. This is the first report describing the presence of GH10 xylanase-encoding genes in P. xylanivorans. Strain 2 and Mz5 contained xylanases which were related to GH10 xylanase of Butyrivibrio sp. Identifying xylanase-encoding genes and activity of these enzymes are a step toward understanding possible functional role of P. xylanivorans in the rumen ecosystem and contribute to providing an improved choice of enzymes for improving fiber digestion in ruminant animals, agricultural biomass utilization for biofuel production, and other industries.

• MeSH
• bachor mikrobiologie   MeSH
• Bacteria klasifikace   enzymologie   genetika   izolace a purifikace   MeSH
• bakteriální proteiny chemie   genetika   metabolismus   MeSH
• endo-1,4-beta-xylanasy chemie   genetika   metabolismus   MeSH
• fylogeneze MeSH
• kinetika MeSH
• kozy MeSH
• xylany metabolismus   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• bakteriální proteiny MeSH
• endo-1,4-beta-xylanasy MeSH
• xylany MeSH

A feeding study was performed to monitor the effect of chitosan intake on the fecal microbiota of ten healthy human subjects. Diversity of microflora was monitored during 8 weeks including 4 weeks of chitosan supplementations. Using denaturing gradient gel electrophoresis (DGGE) analysis of 16S rRNA gene amplicons and quantitative PCR method we revealed possible changes originating in the overall bacterial composition and also in the subpopulation of Bifidobacterium group. DGGE profiles displayed high complexity and individuality for each subject. Considerable variations in the composition of band patterns were observed among different persons. A raised level of fecal Bacteroides in response to chitosan intake was found in all samples. Bifidobacterium levels following chitosan intake increased or remain unchanged. Non-significant increase was, surprisingly, found in the numbers of butyrate-producing bacteria.

• MeSH
• Bacteroides genetika   izolace a purifikace   MeSH
• Bifidobacterium genetika   izolace a purifikace   MeSH
• biodiverzita * MeSH
• chitosan metabolismus   MeSH
• denaturace nukleových kyselin MeSH
• DNA bakterií genetika   MeSH
• dospělí MeSH
• elektroforéza v polyakrylamidovém gelu MeSH
• experimenty na lidech MeSH
• feces mikrobiologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• polymerázová řetězová reakce MeSH
• ribozomální DNA genetika   MeSH
• RNA ribozomální 16S genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• chitosan MeSH
• DNA bakterií MeSH
• ribozomální DNA MeSH
• RNA ribozomální 16S MeSH