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The Open Microbiology Journal 2015The objective of this study was to design a model of dissimilatory sulfate reduction process using the Verhulst function, with a particular focus on the kinetics of...
Model-based Characterization of the Parameters of Dissimilatory Sulfate Reduction Under the Effect of Different Initial Density of Desulfovibrio piger Vib-7 Bacterial Cells.
The objective of this study was to design a model of dissimilatory sulfate reduction process using the Verhulst function, with a particular focus on the kinetics of bacterial growth, sulfate and lactate consumption, and accumulation of hydrogen sulfide and acetate. The effect of the initial density (0.12±0.011, 0.25±0.024, 0.5±0.048 and 1.0±0.096 mg cells/ml of medium) of the sulfate-reducing bacteria Desulfovibrio piger Vib-7 on the growth and dissimilatory sulfate reduction was studied. The exponential growth phase of the D. piger Vib-7 was observed for 72 hours of cultivation at the (0.12 and 0.25 mg/ml) initial concentration of bacterial cells. Sulfate and lactate were consumed incompletely during this time. The increase in the initial concentration of cells to 0.5 and 1 mg/ml led to a shortening of the exponential bacterial growth phase and a shift to the stationary phase of the growth. In the case of 0.5 mg/ml seeding, the stationary growth phase was observed in the 36(th) hour of cultivation. The increase in the initial concentration of cells to 1 mg/ml led to the beginning of the stationary growth phase in 24th hours of cultivation. Under these conditions, sulfate and lactate were consumed completely in the 48th hour of cultivation. The kinetic analysis of the curves of bacterial growth and the process of dissimilatory sulfate reduction by D. piger Vib-7 was carried out.
PubMed: 26668663
DOI: 10.2174/1874285801509010055 -
Polish Journal of Microbiology 2015Intestinal sulfate-reducing bacteria reduce sulfate ions to hydrogen sulfide causing inflammatory bowel diseases of humans and animals. The bacteria consume lactate as...
Intestinal sulfate-reducing bacteria reduce sulfate ions to hydrogen sulfide causing inflammatory bowel diseases of humans and animals. The bacteria consume lactate as electron donor which is oxidized to acetate via pyruvate in process of the dissimilatory sulfate reduction. Pyruvate-ferredoxin oxidoreductase activity and the kinetic properties of the enzyme from intestinal sulfate-reducing bacteria Desulfovibrio piger and Desulfomicrobium sp. have never been well-characterized and have not been yet studied. In this paper we present for the first time the specific activity of pyruvate-ferredoxin oxidoreductase and the kinetic properties of the enzyme in cell-free extracts of both D. piger Vib-7 and Desulfomicrobium sp. Rod-9 intestinal bacterial strains. Microbiological, biochemical, biophysical and statistical methods were used in this work. The optimal temperature (+35°C) and pH 8.5 for enzyme reaction were determined. The spectral analysis of the puri- fied pyruvate-ferredoxin oxidoreductase from the cell-free extracts was demonstrated. Analysis of the kinetic properties of the studied enzyme was carried out. Initial (instantaneous) reaction velocity (V0), maximum amount of the product of reaction (Pmax), the reaction time (half saturation period) and maximum velocity of the pyruvate-ferredoxin oxidoreductase reaction (V ) were defined. Michaelis constants (Km) of the enzyme reaction were calculated for both intestinal bacterial strains. The studies of the kinetic enzyme properties in the intestinal sulfate-reducing bacteria strains in detail can be prospects for clarifying the etiological role of these bacteria in the development of inflammatory bowel diseases.
Topics: Deltaproteobacteria; Desulfovibrio; Gene Expression Regulation, Bacterial; Gene Expression Regulation, Enzymologic; Hydrogen-Ion Concentration; Kinetics; Pyruvate Synthase; Temperature
PubMed: 26373169
DOI: No ID Found -
Acta Biochimica Polonica 2015Phosphotransacetylase activity and the kinetic properties of the enzyme from intestinal sulfate-reducing bacteria Desulfovibrio piger and Desulfomicrobium sp. has never...
Phosphotransacetylase activity and the kinetic properties of the enzyme from intestinal sulfate-reducing bacteria Desulfovibrio piger and Desulfomicrobium sp. has never been well-characterized and has not been studied yet. In this paper, the specific activity of phosphotransacetylase and the kinetic properties of the enzyme in cell-free extracts of both D. piger Vib-7 and Desulfomicrobium sp. Rod-9 intestinal bacterial strains were presented at the first time. The microbiological, biochemical, biophysical and statistical methods in this work were used. The optimal temperature and pH for enzyme reaction was determined. Analysis of the kinetic properties of the studied enzyme was carried out. Initial (instantaneous) reaction velocity (V0), maximum amount of the product of reaction (Pmax), the reaction time (half saturation period, τ) and maximum velocity of the phosphotransacetylase reaction (Vmax) were defined. Michaelis constants (Km) of the enzyme reaction (3.36 ± 0.35 mM for D. piger Vib-7, 5.97 ± 0.62 mM for Desulfomicrobium sp. Rod-9) were calculated. The studies of the phosphotransacetylase in the process of dissimilatory sulfate reduction and kinetic properties of this enzyme in intestinal sulfate-reducing bacteria, their production of acetate in detail can be perspective for clarification of their etiological role in the development of the humans and animals bowel diseases. These studies might help in predicting the development of diseases of the gastrointestinal tract, by providing further details on the etiology of bowel diseases which are very important for the clinical diagnosis of these disease types.
Topics: Bacteria; Hydrogen-Ion Concentration; Intestines; Kinetics; Oxidation-Reduction; Phosphate Acetyltransferase; Sulfates; Temperature
PubMed: 25781158
DOI: 10.18388/abp.2014_845 -
The Open Microbiology Journal 2014Activity of acetate kinase in cell-free extracts and individual fractions and the kinetic properties of the enzyme obtained from the Desulfovibrio piger Vib-7 and...
Activity of acetate kinase in cell-free extracts and individual fractions and the kinetic properties of the enzyme obtained from the Desulfovibrio piger Vib-7 and Desulfomicrobium sp. Rod-9 intestinal bacterial strains were presented at the first time. The highest activity of the enzyme was measured in the cell-free extracts (1.52 ± 0.163 and 0.46 ± 0.044 U × mg-1 protein for D. piger Vib-7 and Desulfomicrobium sp. Rod-9, respectively) compared to other fractions. The specific activity of acetate kinase in the extracts of both bacterial strains was determined at different temperature and pH. Analysis of the kinetic properties of the purified acetate kinase was carried out. The acetate kinase activity, initial (instantaneous) reaction rate (V0) and maximum rate of the acetate kinase reaction (Vmax) in D. piger Vib-7 and Desulfomicrobium sp. Rod-9 intestinal bacterial strains were defined. Michaelis constants (KmAcetyl phosphate and KmADP) of the enzyme reaction (2.54 ± 0.26 and 2.39 ± 0.24 mM for D. piger Vib-7 as well as 2.68 ± 0.25 and 2.47 ± 0.27 mM for Desulfomicrobium sp. Rod-9, respectively) were calculated. The described results of acetate kinase, an important enzyme in the process of organic compounds oxidation and dissimilatory sulfate reduction would be perspective and useful for clarification of the etiological role of these bacteria in the development of inflammatory bowel diseases in humans and animals.
PubMed: 25598851
DOI: 10.2174/1874285801408010138 -
Proceedings of the National Academy of... Aug 2013Sulfate-reducing bacteria (SRB) colonize the guts of ∼50% of humans. We used genome-wide transposon mutagenesis and insertion-site sequencing, RNA-Seq, plus mass... (Comparative Study)
Comparative Study
Sulfate-reducing bacteria (SRB) colonize the guts of ∼50% of humans. We used genome-wide transposon mutagenesis and insertion-site sequencing, RNA-Seq, plus mass spectrometry to characterize genetic and environmental factors that impact the niche of Desulfovibrio piger, the most common SRB in a surveyed cohort of healthy US adults. Gnotobiotic mice were colonized with an assemblage of sequenced human gut bacterial species with or without D. piger and fed diets with different levels and types of carbohydrates and sulfur sources. Diet was a major determinant of functions expressed by this artificial nine-member community and of the genes that impact D. piger fitness; the latter includes high- and low-affinity systems for using ammonia, a limiting resource for D. piger in mice consuming a polysaccharide-rich diet. Although genes involved in hydrogen consumption and sulfate reduction are necessary for its colonization, varying dietary-free sulfate levels did not significantly alter levels of D. piger, which can obtain sulfate from the host in part via cross-feeding mediated by Bacteroides-encoded sulfatases. Chondroitin sulfate, a common dietary supplement, increased D. piger and H2S levels without compromising gut barrier integrity. A chondroitin sulfate-supplemented diet together with D. piger impacted the assemblage's substrate utilization preferences, allowing consumption of more reduced carbon sources and increasing the abundance of the H2-producing Actinobacterium, Collinsella aerofaciens. Our findings provide genetic and metabolic details of how this H2-consuming SRB shapes the responses of a microbiota to diet ingredients and a framework for examining how individuals lacking D. piger differ from those who harbor it.
Topics: Animals; Bromodeoxyuridine; Chondroitin Sulfates; DNA Primers; DNA Transposable Elements; Desulfovibrio; Diet; Dietary Supplements; Feces; Gas Chromatography-Mass Spectrometry; Gastrointestinal Tract; Genetic Vectors; Humans; Hydrogen Sulfide; Mass Spectrometry; Mice; Mutagenesis; Sequence Analysis, DNA; Species Specificity
PubMed: 23898195
DOI: 10.1073/pnas.1312524110 -
FEMS Immunology and Medical Microbiology Jun 2012The relative abundance of different groups of sulphate-reducing bacteria (SRB) in faecal DNA collected before and after therapy from patients suffering from Crohn's...
The relative abundance of different groups of sulphate-reducing bacteria (SRB) in faecal DNA collected before and after therapy from patients suffering from Crohn's disease (CD), irritable bowel syndrome (IBS) or ulcerative colitis (UC) has been compared with that from healthy controls. Growth tests revealed that SRB were not more abundant in samples from patients with CD before treatment than in the healthy control group. For most of the 128 samples available, these preliminary results were confirmed using degenerate PCR primers that amplify the dsrAB gene. However, some samples from patients with CD before treatment contained a growth inhibitor that was absent from IBS or UC samples. In-depth sequencing of PCR-generated dsrB fragments revealed that the diversity detected was surprisingly low, with only eight strains of SRB and the sulphite-reducing bacterium, Bilophila wadsworthia, detected above the 0.1% threshold. The proportion of the two major species detected, B. wadsworthia and Desulfovibrio piger, was as high as 93.5% of the total SRB population in the healthy control group and lower in all patient groups. Four previously undescribed species were found: it is impossible to predict whether they are sulphate or sulphite-reducing bacteria.
Topics: Anti-Bacterial Agents; Bacteria; Biota; DNA Primers; DNA, Bacterial; Feces; High-Throughput Nucleotide Sequencing; Human Experimentation; Humans; Inflammatory Bowel Diseases; Metagenome; Oxidation-Reduction; Polymerase Chain Reaction; Sulfates
PubMed: 22309113
DOI: 10.1111/j.1574-695X.2012.00935.x -
The ISME Journal Jan 2012Hydrogenotrophic microbiota have a significant impact on colonic health; however, little is known about their diversity and ecology in situ. Here, molecular-based...
Hydrogenotrophic microbiota have a significant impact on colonic health; however, little is known about their diversity and ecology in situ. Here, molecular-based methods and multivariate analyses were used to examine the abundance and diversity of mucosa-associated hydrogenotrophic microbes in 90 biopsies collected from right colon, left colon and rectum of 25 healthy subjects. Functional genes of all three hydrogenotrophic groups were detected in at least one colonic region of all subjects. Methanogenic archaea (MA) constituted approximately one half of the hydrogenotrophic microbiota in each colonic region. Sulfate-reducing bacteria (SRB) were more abundant than acetogens in right colon, while acetogens were more abundant than SRB in left colon and rectum. MA genotypes exhibited low diversity, whereas SRB genotypes were diverse and generally similar across the three regions within subject but significantly variable among subjects. Multivariate cluster analysis defined subject-specific patterns for the diversity of SRB genotypes; however, neither subject- nor region-specific clusters were observed for the abundance of hydrogenotrophic functional genes. Sequence analyses of functional gene clones revealed that mucosa-associated SRB were phylogenetically related to Desulfovibrio piger, Desulfovibrio desulfuricans and Bilophila wadsworthia; whereas MA were related to Methanobrevibacter spp., Mb. smithii and the order Methanomicrobiales. Together these data demonstrate for the first time that the human colonic mucosa is persistently colonized by all three groups of hydrogenotrophic microbes, which exhibit segmental and interindividual variation in abundance and diversity.
Topics: Archaea; Bacteria; Colon; Desulfovibrio; Female; Gram-Negative Anaerobic Straight, Curved, and Helical Rods; Humans; Intestinal Mucosa; Male; Metagenome; Methanobacteriaceae; Middle Aged; Rectum
PubMed: 21753800
DOI: 10.1038/ismej.2011.90 -
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 -
Proceedings of the National Academy of... Jun 2006Our colons harbor trillions of microbes including a prominent archaeon, Methanobrevibacter smithii. To examine the contributions of Archaea to digestive health, we...
Our colons harbor trillions of microbes including a prominent archaeon, Methanobrevibacter smithii. To examine the contributions of Archaea to digestive health, we colonized germ-free mice with Bacteroides thetaiotaomicron, an adaptive bacterial forager of the polysaccharides that we consume, with or without M. smithii or the sulfate-reducing bacterium Desulfovibrio piger. Whole-genome transcriptional profiling of B. thetaiotaomicron, combined with mass spectrometry, revealed that, unlike D. piger, M. smithii directs B. thetaiotaomicron to focus on fermentation of dietary fructans to acetate, whereas B. thetaiotaomicron-derived formate is used by M. smithii for methanogenesis. B. thetaiotaomicron-M. smithii cocolonization produces a significant increase in host adiposity compared with monoassociated, or B. thetaiotaomicron-D. piger biassociated, animals. These findings demonstrate a link between this archaeon, prioritized bacterial utilization of polysaccharides commonly encountered in our modern diets, and host energy balance.
Topics: Animals; Bacteroides; Colon; Desulfovibrio; Diet; Digestion; Fermentation; Fructans; Germ-Free Life; Humans; Methanobrevibacter; Mice; Molecular Sequence Data; Polysaccharides; Symbiosis
PubMed: 16782812
DOI: 10.1073/pnas.0602187103 -
Journal of Clinical Microbiology Mar 2003To evaluate the prevalence of sulfate-reducing bacteria in septic processes, we searched for these bacteria by culture in 100 consecutive abdominal and pleural pus...
To evaluate the prevalence of sulfate-reducing bacteria in septic processes, we searched for these bacteria by culture in 100 consecutive abdominal and pleural pus specimens. Twelve isolates were obtained from abdominal samples and were identified by a multiplex PCR as Desulfovibrio piger (formerly Desulfomonas pigra) (seven strains), Desulfovibrio fairfieldensis (four strains), and Desulfovibrio desulfuricans (one strain).
Topics: Abdomen; Adolescent; Adult; Aged; Aged, 80 and over; Child; Desulfovibrio; Female; Humans; Male; Middle Aged; Pleura
PubMed: 12624073
DOI: 10.1128/JCM.41.3.1304-1306.2003