Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, have become increasingly prevalent across all human generations. Despite advances in diagnosis, effective long-term therapeutic options remain limited, with many patients experiencing recurrent symptoms after treatment. The multifactorial origins of ulcerative colitis are widely recognized, but the intestinal microbiome, particularly bacteria from the Desulfovibrionaceae family, is thought to play a central role in the pathogenesis of the disease. These bacteria contribute significantly to gut microbial functions, yet their cytotoxic and viability characteristics under disease conditions remain poorly understood. Our review provides insights on recent advancements in methodologies for assessing the cytotoxicity and viability of anaerobic intestinal bacteria, with a specific focus on their relevance to gut health and disease. We introduce overview from current literature on modern techniques including flow cytometry, high-throughput screening, and molecular-based assays, highlighting their applications in understanding the role of Desulfovibrionaceae and other gut microbes in IBD pathogenesis. By bridging methodological advancements with functional implications, this review aims to enhance our understanding of gut microbiota-host interactions, which are crucial for maintaining health and preventing disease through immune modulation, where microbiota help regulate immune responses and prevent excessive inflammation; nutrient metabolism, including the breakdown of dietary fibers into short-chain fatty acids that support gut health; and colonization resistance, where beneficial microbes outcompete harmful pathogens to maintain microbial balance.

• Keywords
• Anaerobic bacteria, Cytotoxicity assays, Gut microbiome, Inflammatory bowel disease, Microbial pathogenesis, Microbiota-host interaction,
• Publication type
• Journal Article MeSH
• Review MeSH

Considerable evidence has accumulated regarding the molecular relationship between gut microbiota (GM) composition and the onset (clinical presentation and prognosis of ulcerative colitis (UC)). In addition, it is well documented that short-chain fatty acid (SCFA)-producing bacteria may play a fundamental role in maintaining an anti-inflammatory intestinal homeostasis, but sulfate- and sulfite reducing bacteria may be responsible for the production of toxic metabolites, such as hydrogen sulfide and acetate. Hence, the present study aimed to assess the GM composition - focusing on sulfate-reducing bacteria (SRB) - in patients with severe, severe-active and moderate UC. Each one of the six enrolled patients provided two stool samples in the following way: one sample was cultivated in a modified SRB-medium before 16S rRNA sequencing and the other was not cultivated. Comparative phylogenetic analysis was conducted on each sample. Percentage of detected gut microbial genera showed considerable variation based on the patients' disease severity and cultivation in the SRB medium. In detail, samples without cultivation from patients with moderate UC showed a high abundance of the genera Bacteroides, Bifidobacterium and Ruminococcus, but after SRB cultivation, the dominant genera were Bacteroides, Klebsiella and Bilophila. On the other hand, before SRB cultivation, the main represented genera in patients with severe UC were Escherichia-Shigella, Proteus, Methanothermobacter and Methanobacterium. However, after incubation in the SRB medium Bacteroides, Proteus, Alistipes and Lachnoclostridium were predominant. Information regarding GM compositional changes in UC patients may aid the development of novel therapeutic strategies (e.g., probiotic preparations containing specific bacterial strains) to counteract the mechanisms of virulence of harmful bacteria and the subsequent inflammatory response that is closely related to the pathogenesis of inflammatory bowel diseases.

• Keywords
• 16S rRNA gene sequencing, gut dysbiosis, gut microbiota, inflammatory bowel disease, sulfate-reducing bacteria, ulcerative colitis,
• Publication type
• Journal Article MeSH

Animal and human feces typically include intestinal sulfate-reducing bacteria (SRB). Hydrogen sulfide and acetate are the end products of their dissimilatory sulfate reduction and may create a synergistic effect. Here, we report NADH and NADPH peroxidase activities from intestinal SRB Desulfomicrobium orale and Desulfovibrio piger. We sought to compare enzymatic activities under the influence of various temperature and pH regimes, as well as to carry out kinetic analyses of enzymatic reaction rates, maximum amounts of the reaction product, reaction times, maximum rates of the enzyme reactions, and Michaelis constants in cell-free extracts of intestinal SRB, D. piger Vib-7, and D. orale Rod-9, collected from exponential and stationary growth phases. The optimal temperature (35 °C) and pH (7.0) for both enzyme's activity were determined. The difference in trends of Michaelis constants (Km) during exponential and stationary phases are noticeable between D. piger Vib-7 and D. orale Rod-9; D. orale Rod-9 showed much higher Km (the exception is NADH peroxidase of D. piger Vib-7: 1.42 ± 0.11 mM) during the both monitored phases. Studies of the NADH and NADPH peroxidases-as putative antioxidant defense systems of intestinal SRB and detailed data on the kinetic properties of this enzyme, as expressed by the decomposition of hydrogen peroxide-could be important for clarifying evolutionary mechanisms of antioxidant defense systems, their etiological role in the process of dissimilatory sulfate reduction, and their possible role in the development of bowel diseases.

• MeSH
• Antioxidants * MeSH
• Cell Extracts MeSH
• Desulfovibrio * MeSH
• Humans MeSH
• NAD MeSH
• NADP MeSH
• Defense Mechanisms MeSH
• Peroxidases MeSH
• Sulfates MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Antioxidants * MeSH
• Cell Extracts MeSH
• NAD MeSH
• NADP MeSH
• NADPH peroxidase MeSH Browser
• Peroxidases MeSH
• Sulfates MeSH

Sulfur is a vital element that all living things require, being a component of proteins and other bio-organic substances. The various kinds and varieties of microbes in nature allow for the transformation of this element. It also should be emphasized that volatile sulfur compounds are typically present in food in trace amounts. Life cannot exist without sulfur, yet it also poses a potential health risk. The colon's sulfur metabolism, which is managed by eukaryotic cells, is much better understood than the S metabolism in gastrointestinal bacteria. Numerous additional microbial processes are anticipated to have an impact on the content and availability of sulfated compounds, as well as intestinal S metabolism. Hydrogen sulfide is the sulfur derivative that has attracted the most attention in relation to colonic health, but it is still unclear whether it is beneficial or harmful. Several lines of evidence suggest that sulfate-reducing bacteria or exogenous hydrogen sulfide may be the root cause of intestinal ailments, including inflammatory bowel diseases and colon cancer. Taurine serves a variety of biological and physiological purposes, including roles in inflammation and protection, additionally, low levels of taurine can be found in bodily fluids, and taurine is the primary sulfur component present in muscle tissue (serum and urine). The aim of this scoping review was to compile data from the most pertinent scientific works about S compounds' existence in food and their metabolic processes. The importance of S compounds in various food products and how these compounds can impact metabolic processes are both stressed in this paper.

• Keywords
• Gut microbiome, Hydrogen sulfide, Sulfate-reducing bacteria, Sulfur assimilation, Sulfur metabolism, Toxicity,
• Publication type
• Journal Article MeSH
• Scoping Review MeSH

This paper is devoted to microscopic methods for the identification of sulfate-reducing bacteria (SRB). In this context, it describes various habitats, morphology and techniques used for the detection and identification of this very heterogeneous group of anaerobic microorganisms. SRB are present in almost every habitat on Earth, including freshwater and marine water, soils, sediments or animals. In the oil, water and gas industries, they can cause considerable economic losses due to their hydrogen sulfide production; in periodontal lesions and the colon of humans, they can cause health complications. Although the role of these bacteria in inflammatory bowel diseases is not entirely known yet, their presence is increased in patients and produced hydrogen sulfide has a cytotoxic effect. For these reasons, methods for the detection of these microorganisms were described. Apart from selected molecular techniques, including metagenomics, fluorescence microscopy was one of the applied methods. Especially fluorescence in situ hybridization (FISH) in various modifications was described. This method enables visual identification of SRB, determining their abundance and spatial distribution in environmental biofilms and gut samples.

• Keywords
• DAPI, Desulfovibrio, FISH, IBD, SRB, SRM, SRP, anaerobic microorganisms, fluorescence microscopy, gut microbiota, habitats, identification, microscopy, sulfate reduction,
• MeSH
• Bacteria metabolism   MeSH
• Ecosystem * MeSH
• Humans MeSH
• Metagenomics MeSH
• Microscopy methods   MeSH
• Oxidation-Reduction MeSH
• Sulfates metabolism   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Review MeSH
• Names of Substances
• Sulfates MeSH

Meta-analysis is a statistical process summarizing comparable data from a number of scientific papers. The use of meta-analysis in microbiology allows decision-making that has an impact on public health policy. It can happen that the primary researches come to different conclusions, although these are targeted with the same research question. It is, therefore, inevitable to have the means to systematically evaluate information and compare research results. Ulcerative colitis together with Crohn's disease are among the two main inflammatory bowel diseases. This chronic disease of the gastrointestinal tract, with an as yet unclear etiology, is presented by an uncontrolled inflammatory immune response in genetically predisposed individuals to as yet undefined environmental factors in interaction with the intestinal microbiota itself. In patients with ulcerative colitis (UC), changes in the composition and relative abundance of microorganisms could be observed. Sulfate-reducing bacteria (SRB), which commonly occur in the large intestine as part of the commensal microbiota of animals and humans involved in the pathogenesis of the disease, have been shown to occur. SRB are anaerobic organisms affecting short-chain fatty acid metabolism. This work outlines the perspectives of the use of meta-analysis for UC and changes in the representation of intestinal organisms in these patients.

• Keywords
• hydrogen sulfide, inflammatory bowel diseases, intestinal microbiome, meta-analysis, sulfate-reducing bacteria, ulcerative colitis,
• Publication type
• Journal Article MeSH
• Review MeSH

The number of cases of oral cavity inflammation in the population has been recently increasing, with periodontitis being the most common disease. It is caused by a change in the microbial composition of the biofilm in the periodontal pockets. In this context, an increased incidence of sulfate-reducing bacteria (SRB) in the oral cavity has been found, which are a part of the common microbiome of the mouth. This work is devoted to the description of the diversity of SRB isolated from the oral cavity. It also deals with the general description of periodontitis in terms of manifestations and origin. It describes the ability of SRB to participate in its development, although their effect on periodontal inflammation is not fully understood. The production of hydrogen sulfide as a cytochrome oxidase inhibitor may play a role in the etiology. A meta-analysis was conducted based on studies of the occurrence of SRB in humans.

• Keywords
• SRB, dental plaque, hydrogen sulfide, meta-analysis, oral cavity, periodontal disease, periodontitis, sulfate, sulfate-reducing bacteria,
• Publication type
• Journal Article MeSH
• Review MeSH