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FEMS Microbiology Ecology Aug 2009The production of hydrogen sulphide, an end product of metabolism by the sulphate-reducing bacteria (SRB) has been cited as a potential aetiological agent in...
The production of hydrogen sulphide, an end product of metabolism by the sulphate-reducing bacteria (SRB) has been cited as a potential aetiological agent in gastrointestinal disease. Quantitative PCR (Q-PCR) assays to enumerate desulfovibrios from two gastrointestinal disease groups: colorectal cancer (CRC) n=27 and polypectomized individuals (PP) n=27, and two healthy control groups, elderly (H1) n=8 and young adults (H2) n=30 was performed. Analysis of Desulfovibrio sp. diversity using the dissimilarity sulphite reductase (dsrAB) gene as a molecular marker was also undertaken. Q-PCR detected Desulfovibrio sp. in all samples and no significant difference was observed for PP, H1, H2 with gene copy numbers of Desulfovibrio sp. averaging at 10(6) g(-1) of faeces. Significantly reduced numbers of Desulfovibrio sp. were observed for CRC (10(5) g(-1)) compared with both PP and H2 groups (P<0.05). Diversity analysis indicated that a low Desulfovibrio sp. diversity and the predominance of Desulfovibrio piger was a feature of both healthy and disease groups. In addition, a dsrAB gene sequence distantly related to a Gram-positive SRB was also recovered, highlighting the importance of cultivation-independent techniques for furthering our understanding of the diversity of the human gastrointestinal ecosystem.
Topics: Adult; Aged; Biodiversity; Colon; Colonic Polyps; Colorectal Neoplasms; DNA, Bacterial; Desulfovibrio; Feces; Female; Gene Dosage; Humans; Male; Middle Aged; Molecular Sequence Data; Phylogeny; Polymerase Chain Reaction; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Young Adult
PubMed: 19496818
DOI: 10.1111/j.1574-6941.2009.00709.x