Evaluation of Physiological Parameters of Intestinal Sulfate-Reducing Bacteria Isolated from Patients Suffering from IBD and Healthy People

Abstract

Background: Inflammatory bowel diseases (IBDs) are multifactorial illnesses of the intestine, to which microorganisms are contributing. Among the contributing microorganisms, sulfate-reducing bacteria (SRB) are suggested to be involved in the process of bowel inflammation due to the production of hydrogen sulfide (H2S) by dissimilatory sulfate reduction. The aims of our research were to physiologically examine SRB in fecal samples of patients with IBD and a control group, their identification, the study of the process of dissimilatory sulfate reduction (sulfate consumption and H2S production) and biomass accumulation. Determination of biogenic elements of the SRB and evaluation of obtained parameters by using statistical methods were also included in the research. The material for the research consisted of 14 fecal samples, which was obtained from patients and control subjects. Methods: Microscopic techniques, microbiological, biochemical, biophysical methods and statistical analysis were included. Results: Colonies of SRB were isolated from all the fecal samples, and subsequently, 35 strains were obtained. Vibrio-shaped cells stained Gram-negative were dominant in all purified studied strains. All strains had a high percentage of similarity by the 16S rRNA gene with deposited sequences in GenBank of Desulfovibrio vulgaris. Cluster analysis of sulfate reduction parameters allowed the grouping of SRB strains. Significant (p < 0.05) differences were not observed between healthy individuals and patients with IBD with regard to sulfate reduction parameters (sulfate consumption, H2S and biomass accumulation). Moreover, we found that manganese and iron contents in the cell extracts are higher among healthy individuals in comparison to unhealthy individuals that have an intestinal bowel disease, especially ulcerative colitis. Conclusions: The observations obtained from studying SRB emphasize differences in the intestinal microbial processes of healthy and unhealthy people.

The Association of Plasma-Free Branched-Chain Amino Acids with Disease Related Parameters in Ulcerative Colitis

“…Suppression of mitochondrial genes and function [ 13 ], disruption of the intestinal mucosal barrier and bacterial invasion resulting in intestinal inflammation, and further TLR4/NF-κB stimulation in intestinal epithelial cells are some of the proposed mechanisms [ 14 ]. The role of intestinal microbiota has also been investigated and there seems to be evidence on differences in the intestinal microbial metabolism between healthy and patients with IBD [ 15 ] as well as on the involvement of bacterial sulfate metabolism in gut inflammation [ 16 , 17 , 18 ] More specifically, sulphate reducing bacteria use sulfate as an electron acceptor in dissimilatory sulfate reduction and the final product is H2S, a potential toxic, mutagenic and cancerogenic compound [ 19 ].…”

Intestinal Microbiota and Perspectives of the Use of Meta-Analysis for Comparison of Ulcerative Colitis Studies

“…Ulcerative colitis together with Crohn’s disease are the two main inflammatory bowel diseases (IBD) [ 21 , 22 , 23 , 24 , 25 ]. These chronic diseases with an as yet unclear etiology are manifested by an uncontrollable inflammatory immune response to as yet undefined environmental factors in genetically predisposed individuals interacting with their own intestinal microbiota [ 5 , 9 , 26 , 27 ]. The main factors for the development of ulcerative colitis are demonstrated in Figure 2 .…”

Microscopic Methods for Identification of Sulfate-Reducing Bacteria from Various Habitats

“…The presence of the genus Desulfovibrio has long been reported in the rumen of ruminants, in the intestines of termites and the intestines of animals and humans [5,[44][45][46][47]. SRB are commonly non-pathogenic and can be successfully isolated from fresh human feces [11], but have also been associated with inflammatory bowel diseases, and their significance has been investigated ever since [48].…”