natural relationships among sulfate-reducing eubacteria. | phylogenetic relationships among 20 nonsporeforming and two endospore-forming species of sulfate-reducing eubacteria were inferred from comparative 16s rrna sequencing. all genera of mesophilic sulfate-reducing eubacteria except the new genus desulfomicrobium and the gliding desulfonema species were included. the sporeforming species desulfotomaculum ruminis and desulfotomaculum orientis were found to be gram-positive organisms sharing 83% 16s rrna sequence similarity, indicating that this genus ... | 1989 | 2480344 |
occurrence of sulphate-reducing bacteria in human faeces and the relationship of dissimilatory sulphate reduction to methanogenesis in the large gut. | sulphate-reducing bacteria (srb) were enumerated in 40 faecal samples obtained from two different human populations in the united kingdom and rural south africa. species able to metabolize acetate, lactate, propionate, butyrate, h2/co2, succinate, pyruvate, valerate, ethanol and a glutamate/serine/alanine mixture were found in faeces from both populations. although a variety of nutritionally and morphologically distinct species of srb belonging to the genera desulfotomaculum, desulfobacter, desu ... | 1988 | 3204069 |
use of a three-stage continuous culture system to study the effect of mucin on dissimilatory sulfate reduction and methanogenesis by mixed populations of human gut bacteria. | a mixed culture of human fecal bacteria was grown for 120 days in a three-stage continuous culture system. to reproduce some of the nutritional and ph characteristics of the large gut, each vessel had a different operating volume (0.3, 0.5, and 0.8 liter) and ph (6.0, 6.5, and 7.0). a mixture of polysaccharides and proteins was used as carbon and nitrogen sources. measurements of h2, ch4, s2-, sulfate reduction rates, sulfate-reducing bacteria (srb), and volatile fatty acids were made throughout ... | 1988 | 3214155 |
population dynamics of propionate-oxidizing bacteria under methanogenic and sulfidogenic conditions in anaerobic granular sludge. | laboratory-scale upflow anaerobic sludge-bed reactors were inoculated with industrial granular sludge and fed with either propionate or propionate and sulfate. the population dynamics of the propionate-oxidizing bacteria desulfobulbus sp. and the syntrophically growing strain syn7 were studied in reactors by dot blot and in situ hybridization with 16s rrna-based oligonucleotide probes. | 1996 | 8787413 |
characterization of microbial communities in anaerobic bioreactors using molecular probes. | the microbial community structure of twenty-one single-phase and one two-phase full-scale anaerobic sewage sludge digesters was evaluated using oligonucleotide probes complementary to conserved tracts of the 16s rrnas of phylogenetically defined groups of methanogens and sulfate-reducing bacteria. these probe results were interpreted in combination with results from traditional chemical analyses and metabolic activity assays. it was determined that methanogens in "healthy" mesophilic, single-pha ... | 1995 | 8821785 |
distribution of sulfate-reducing bacteria in a stratified fjord (mariager fjord, denmark) as evaluated by most-probable-number counts and denaturing gradient gel electrophoresis of pcr-amplified ribosomal dna fragments. | the sulfate-reducing bacterial populations of a stratified marine water column, mariager fjord, denmark, were investigated by molecular and culture-dependent approaches in parallel. denaturing gradient gel electrophoresis (dgge) of pcr-amplified 16s rrna and dna encoding rrna (rdna) isolated from the water column indicated specific bacterial populations in different water column layers and revealed a highly differentiated pattern of rrna- and rdna-derived pcr amplificates, probably reflecting ac ... | 1996 | 8919802 |
genome sizes of desulfovibrio desulfuricans, desulfovibrio vulgaris, and desulfobulbus propionicus estimated by pulsed-field gel electrophoresis of linearized chromosomal dna. | pulsed-field gel electrophoresis (pfge) of linearized, full-length chromosomal dna was used to estimate the genome sizes of three species of sulfate-reducing bacteria. genome sizes of desulfovibrio desulfuricans, desulfovibrio vulgaris, and desulfobulbus propionicus were estimated to be 3.1, 3.6, and 3.7 mb, respectively. these values are double the genome sizes previously determined for two desulfovibrio species by two-dimensional agarose gel electrophoresis of dna cut with restriction enzymes. ... | 1997 | 9142739 |
structural and functional dynamics of sulfate-reducing populations in bacterial biofilms | we describe the combined application of microsensors and molecular techniques to investigate the development of sulfate reduction and of sulfate-reducing bacterial populations in an aerobic bacterial biofilm. microsensor measurements for oxygen showed that anaerobic zones developed in the biofilm within 1 week and that oxygen was depleted in the top 200 to 400 &mgr;m during all stages of biofilm development. sulfate reduction was first detected after 6 weeks of growth, although favorable conditi ... | 1998 | 9758792 |
molecular phylogenetic and biogeochemical studies of sulfate-reducing bacteria in the rhizosphere of spartina alterniflora | the population composition and biogeochemistry of sulfate-reducing bacteria (srb) in the rhizosphere of the marsh grass spartina alterniflora was investigated over two growing seasons by molecular probing, enumerations of culturable srb, and measurements of so42- reduction rates and geochemical parameters. so42- reduction was rapid in marsh sediments with rates up to 3.5 &mgr;mol ml-1 day-1. rates increased greatly when plant growth began in april and decreased again when plants flowered in late ... | 1999 | 10224021 |
analyses of spatial distributions of sulfate-reducing bacteria and their activity in aerobic wastewater biofilms. | the vertical distribution of sulfate-reducing bacteria (srb) in aerobic wastewater biofilms grown on rotating disk reactors was investigated by fluorescent in situ hybridization (fish) with 16s rrna-targeted oligonucleotide probes. to correlate the vertical distribution of srb populations with their activity, the microprofiles of o(2), h(2)s, no(2)(-), no(3)(-), nh(4)(+), and ph were measured with microelectrodes. in addition, a cross-evaluation of the fish and microelectrode analyses was perfor ... | 1999 | 10543829 |
characterization of the desulforubidin operons from desulfobacter vibrioformis and desulfobulbus rhabdoformis. | the genes encoding the desulforubidin type of dissimilatory sulfite reductase (dsr) from the sulfate-reducing bacteria desulfobacter vibrioformis and desulfobulbus rhabdoformis were cloned and sequenced. similar to the genes for dissimilatory sulfite reductase from the genera archaeoglobus, desulfovibrio and desulfotomaculum the dsr genes were found to form an operon, dsrabd, where dsra and dsrb encode the structural subunits, alpha and beta, of dsr, respectively. dsrd encodes a conserved unknow ... | 2000 | 10779710 |
sulfate-reducing bacteria methylate mercury at variable rates in pure culture and in marine sediments. | differences in methylmercury (ch(3)hg) production normalized to the sulfate reduction rate (srr) in various species of sulfate-reducing bacteria (srb) were quantified in pure cultures and in marine sediment slurries in order to determine if srb strains which differ phylogenetically methylate mercury (hg) at similar rates. cultures representing five genera of the srb (desulfovibrio desulfuricans, desulfobulbus propionicus, desulfococcus multivorans, desulfobacter sp. strain bg-8, and desulfobacte ... | 2000 | 10831421 |
development of oligonucleotide probes and pcr primers for detecting phylogenetic subgroups of sulfate-reducing bacteria. | pcr primer sets for the 16s rrna gene of six phylogenetic groups of sulfate-reducing bacteria (srb) were designed. their application in conjunction with group-specific internal oligonucleotide probes was used to detect srb dna in samples of landfill leachate. six generic/suprageneric groups could be differentiated: desulfotomaculum:; desulfobulbus:; desulfobacterium:; desulfobacter:; desulfococcus:-desulfonema:-desulfosarcina:; desulfovibrio:-desulfomicrobium: the predicted specificities of the ... | 2000 | 10878133 |
aspects of bioavailability of mercury for methylation in pure cultures of desulfobulbus propionicus (1pr3). | we have previously hypothesized that sulfide inhibits hg methylation by decreasing its bioavailability to sulfate-reducing bacteria (srb), the important methylators of hg in natural sediments. with a view to designing a bioassay to test this hypothesis, we investigated a number of aspects of hg methylation by the srb desulfobulbus propionicus, including (i) the relationship between cell density and methylmercury (mehg) production, (ii) the time course of hg methylation relative to growth stage, ... | 2001 | 11133427 |
use of 16s rrna-targeted oligonucleotide probes to investigate the distribution of sulphate-reducing bacteria in estuarine sediments. | the distribution of sulphate-reducing bacteria (srbs) in three anaerobic sediments, one predominantly freshwater and low sulphate and two predominantly marine and high sulphate, on the river tama, tokyo, japan, was investigated using 16s rrna-targeted oligonucleotide probes. hybridisation results and sulphate reduction measurements indicated that srbs are a minor part of the bacterial population in the freshwater sediments. only desulfobulbus and desulfobacterium were detected, representing 1.6% ... | 2001 | 11451520 |
phylogenetic identification and substrate uptake patterns of sulfate-reducing bacteria inhabiting an oxic-anoxic sewer biofilm determined by combining microautoradiography and fluorescent in situ hybridization. | we simultaneously determined the phylogenetic identification and substrate uptake patterns of sulfate-reducing bacteria (srb) inhabiting a sewer biofilm with oxygen, nitrate, or sulfate as an electron acceptor by combining microautoradiography and fluorescent in situ hybridization (mar-fish) with family- and genus-specific 16s rrna probes. the mar-fish analysis revealed that desulfobulbus hybridized with probe 660 was a dominant srb subgroup in this sewer biofilm, accounting for 23% of the total ... | 2002 | 11772645 |
successional development of sulfate-reducing bacterial populations and their activities in an activated sludge immobilized agar gel film. | a combination of fluorescence in situ hybridization (fish), microprofiles, and denaturing gradient gel electrophoresis (dgge) analysis of pcr-amplified 16s rdna fragments followed by hybridization analysis with specific probes was applied to investigate successional development of sulfate-reducing bacteria (srb) community structure and in situ sulfide production activity within an activated sludge immobilized agar gel film. in this model biofilm system, since biases arising from biofilm heteroge ... | 2002 | 11870602 |
successional development of sulfate-reducing bacterial populations and their activities in a wastewater biofilm growing under microaerophilic conditions. | a combination of fluorescence in situ hybridization, microprofiles, denaturing gradient gel electrophoresis of pcr-amplified 16s ribosomal dna fragments, and 16s rrna gene cloning analysis was applied to investigate successional development of sulfate-reducing bacteria (srb) community structure and in situ sulfide production activity within a biofilm growing under microaerophilic conditions (dissolved oxygen concentration in the bulk liquid was in the range of 0 to 100 microm) and in the presenc ... | 2002 | 11872492 |
nitrite reductase activity of sulphate-reducing bacteria prevents their inhibition by nitrate-reducing, sulphide-oxidizing bacteria. | sulphate-reducing bacteria (srb) can be inhibited by nitrate-reducing, sulphide-oxidizing bacteria (nr-sob), despite the fact that these two groups are interdependent in many anaerobic environments. practical applications of this inhibition include the reduction of sulphide concentrations in oil fields by nitrate injection. the nr-sob thiomicrospira sp. strain cvo was found to oxidize up to 15 mm sulphide, considerably more than three other nr-sob strains that were tested. sulphide oxidation inc ... | 2003 | 12823193 |
electron transfer by desulfobulbus propionicus to fe(iii) and graphite electrodes. | desulfobulbus propionicus was able to grow with fe(iii), the humic acids analog anthraquinone-2,6-disulfonate (aqds), or a graphite electrode as an electron acceptor. these results provide an explanation for the enrichment of desulfobulbaceae species on the surface of electrodes harvesting electricity from anaerobic marine sediments and further expand the diversity of microorganisms known to have the ability to use both sulfate and fe(iii) as an electron acceptor. | 2004 | 14766612 |
quantification of gram-negative sulphate-reducing bacteria in rice field soil by 16s rrna gene-targeted real-time pcr. | for the quantification of gram-negative sulphate reducers in rice fields, 11 real-time pcr assays were established targeting 16s rrna genes combined with sybrgreen detection. three of these assays were specific for the "main" groups, i.e. the desulfovibrionaceae, the desulfobacteraceae and desulfobulbus sp., whereas eight assays were developed for subgroups within the first two main groups. the detection limits of the assays were between 2 x 10(5) and 4 x 10(3) targets g(-1) (wet weight) or less ... | 2004 | 15063062 |
nested pcr-denaturing gradient gel electrophoresis approach to determine the diversity of sulfate-reducing bacteria in complex microbial communities. | here, we describe a three-step nested-pcr-denaturing gradient gel electrophoresis (dgge) strategy to detect sulfate-reducing bacteria (srb) in complex microbial communities from industrial bioreactors. in the first step, the nearly complete 16s rrna gene was amplified using bacterial primers. subsequently, this product was used as a template in a second pcr with group-specific srb primers. a third round of amplification was conducted to obtain fragments suitable for dgge. the largest number of b ... | 2005 | 15870318 |
identification of candidate periodontal pathogens and beneficial species by quantitative 16s clonal analysis. | most studies of the bacterial etiology of periodontitis have used either culture-based or targeted dna approaches, and so it is likely that pathogens remain undiscovered. the purpose of this study was to use culture-independent, quantitative analysis of biofilms associated with chronic periodontitis and periodontal health to identify pathogens and beneficial species. samples from subjects with periodontitis and controls were analyzed using ribosomal 16s cloning and sequencing. several genera, ma ... | 2005 | 16081935 |
competition for sulfate and ethanol among desulfobacter, desulfobulbus, and desulfovibrio species isolated from intertidal sediments. | competition for sulfate and ethanol among desulfobacter, desulfobulbus, and desulfovibrio species isolated from estuarine sediments was studied in energy-limited chemostats. desulfovibrio baculatus was the most successful competitor for limiting amounts of sulfate and ethanol, followed by desulfobulbus propionicus. the success of desulfovibrio baculatus was dependent on the availability of sufficient iron. of the three species studied, desulfobacter postgatei was the least successful competitor ... | 1984 | 16346474 |
properties of desulfovibrio carbinolicus sp. nov. and other sulfate-reducing bacteria isolated from an anaerobic-purification plant. | several sulfate-reducing microorganisms were isolated from an anaerobic-purification plant. four strains were classified as desulfovibrio desulfuricans, desulfovibrio sapovorans, desulfobulbus propionicus, and desulfovibrio sp. the d. sapovorans strain contained poly-beta-hydroxybutyrate granules and seemed to form extracellular vesicles. a fifth isolate, desulfovibrio sp. strain edk82, was a gram-negative, non-spore-forming, nonmotile, curved organism. it was able to oxidize several substrates, ... | 1987 | 16347324 |
immunological cross-reactivities of adenosine-5'-phosphosulfate reductases from sulfate-reducing and sulfide-oxidizing bacteria. | crude extracts from 14 species of sulfate-reducing bacteria comprising the genera desulfovibrio, desulfotomaculum, desulfobulbus, and desulfosarcina and from three species of sulfide-oxidizing bacteria were tested in an enzyme-linked immunosorbent assay with polyclonal antisera to adenosine 5'-phosphosulfate reductase from desulfovibrio desulfuricans g100a. the results showed that extracts from desulfovibrio species were all highly cross-reactive, whereas extracts from the other sulfate-reducing ... | 1991 | 16348440 |
novel processes for anaerobic sulfate production from elemental sulfur by sulfate-reducing bacteria. | sulfate reducers and related organisms which had previously been found to reduce fe(iii) with h(2) or organic electron donors oxidized s to sulfate when mn(iv) was provided as an electron acceptor. organisms catalyzing this reaction in washed cell suspensions included desulfovibrio desulfuricans, desulfomicrobium baculatum, desulfobacterium autotrophicum, desulfuromonas acetoxidans, and geobacter metallireducens. these organisms produced little or no sulfate from s with fe(iii) as a potential el ... | 1994 | 16349323 |
mercury methylation from unexpected sources: molybdate-inhibited freshwater sediments and an iron-reducing bacterium. | methylmercury has been thought to be produced predominantly by sulfate-reducing bacteria in anoxic sediments. here we show that in circumneutral ph sediments (clear lake, ca) application of a specific inhibitor of sulfate-reducing bacteria at appropriate concentrations typically inhibited less than one-half of all anaerobic methylation of added divalent mercury. this suggests that one or more additional groups of microbes are active methylators in these sediments impacted by a nearby abandoned m ... | 2006 | 16391078 |
[distribution, diversity, and activity of sulfate-reducing bacteria in the water column in gek-gel lake, azerbaijan]. | the distribution and activity of sulfate-reducing bacteria (srb) in the water column of the alpine meromictic gek-gel lake were studied. apart from traditional microbiological methods based on cultivation and on measuring the process rates with radioactive labels, in situ fluorescent hybridization (fish) was used, which enables identification and quantification without cultivating organisms. the peak rate of sulfate reduction, 0.486 microg s/(l day), was found in the chemocline at 33 m. the peak ... | 2006 | 16579451 |
[adhesion of sulphate-reducing bacteria to steel under cathode polarization]. | adhesion of different (as to their corrosion aggression) strains of sulphate-reducing bacteria to steel has been studied under cathode polarization at various potentials: -800, -900, -1000, -1200 mv. it has been established that cathode polarization differently affects the adhesion of strain of sulphate-reducing bacteria with various aggression to steel. correlation between the bacterial strains aggression and the number of cells adhered to metal have been noted. the cells of aggressive strains ... | 2006 | 16686219 |
low strength wastewater treatment under low temperature conditions by a novel sulfur redox action process. | the objective of this research is to make a novel wastewater treatment process activated by a sulfur-redox cycle action of microbes in low temperature conditions. this action is carried out by sulfate-reducing bacteria (srb) and sulfur-oxidizing bacteria (sob). the process was comprised of a uasb reactor as pre-treatment and an aerobic downflow hanging sponge (dhs) reactor as post-treatment. as the results of reactor operation, the whole process achieved that over 90% of codcr removal efficiency ... | 2006 | 16749445 |
exposure to sulfide causes populations shifts in sulfate-reducing consortia. | the shift in the community structure of a mixed culture of sulfate-reducing bacteria (srb) at 0.5, 0.75, 1, and 1.5 kg m(-3) sulfide loadings was investigated in an anaerobic continuous bioreactor used for treatment of sulfate-containing wastewater by fluorescence in situ hybridization (fish), using srb species-specific and group-specific 16s rrna-targeting probes. hybridization analysis using these 16s rrna-targeted oligonucleotide probes revealed that sulfide was toxic for desulfonema, desulfo ... | 2006 | 16814989 |
molecular analysis of deep subsurface cretaceous rock indicates abundant fe(iii)- and s(zero)-reducing bacteria in a sulfate-rich environment. | a multilevel sampler (mls) was emplaced in a borehole straddling anaerobic, sulfate-rich cretaceous-era shale and sandstone rock formations approximately 200 m below ground surface at cerro negro, new mexico. sterile quartzite sand contained in chambers in the sampler allowed in situ colonization and recovery of nucleic acids for molecular analyses. denaturing gradient gel electrophoresis and 16s rrna gene cloning results indicated a homogeneously distributed bacterial community across the shale ... | 2006 | 16343329 |
identification of population dynamics in sulfate-reducing consortia on exposure to sulfate. | the microbial population structure and function of a mixed culture of sulfate-reducing bacteria (srb) maintained in anaerobic continuous bioreactors were tracked before and after a major perturbation, which involved the addition of sulfate to the influent of a bioreactor when operated at steady state at 35 degrees c, ph 7.8 and a 2.5 day residence time with feed stream containing 10 and 15 kg m(-3) sulfate as terminal electron acceptor and 19.6 and 29.4 kg m(-3) ethanol as carbon source and elec ... | 2006 | 17008063 |
analysis of diversity and activity of sulfate-reducing bacterial communities in sulfidogenic bioreactors using 16s rrna and dsrb genes as molecular markers. | here we describe the diversity and activity of sulfate-reducing bacteria (srb) in sulfidogenic bioreactors by using the simultaneous analysis of pcr products obtained from dna and rna of the 16s rrna and dissimilatory sulfite reductase (dsrab) genes. we subsequently analyzed the amplified gene fragments by using denaturing gradient gel electrophoresis (dgge). we observed fewer bands in the rna-based dgge profiles than in the dna-based profiles, indicating marked differences in the populations pr ... | 2007 | 17098925 |
diversity and abundance of aerobic and anaerobic methane oxidizers at the haakon mosby mud volcano, barents sea. | submarine mud volcanoes are formed by expulsions of mud, fluids, and gases from deeply buried subsurface sources. they are highly reduced benthic habitats and often associated with intensive methane seepage. in this study, the microbial diversity and community structure in methane-rich sediments of the haakon mosby mud volcano (hmmv) were investigated by comparative sequence analysis of 16s rrna genes and fluorescence in situ hybridization. in the active volcano center, which has a diameter of a ... | 2007 | 17369343 |
dissimilatory arsenate reduction with sulfide as electron donor: experiments with mono lake water and isolation of strain mlms-1, a chemoautotrophic arsenate respirer. | anoxic bottom water from mono lake, california, can biologically reduce added arsenate without any addition of electron donors. of the possible in situ inorganic electron donors present, only sulfide was sufficiently abundant to drive this reaction. we tested the ability of sulfide to serve as an electron donor for arsenate reduction in experiments with lake water. reduction of arsenate to arsenite occurred simultaneously with the removal of sulfide. no loss of sulfide occurred in controls witho ... | 2004 | 15128527 |
co-existence of physiologically similar sulfate-reducing bacteria in a full-scale sulfidogenic bioreactor fed with a single organic electron donor. | a combination of culture-dependent and independent methods was used to study the co-existence of different sulfate-reducing bacteria (srb) in an upflow anaerobic sludge bed reactor treating sulfate-rich wastewater. the wastewater was fed with ethanol as an external electron donor. twenty six strains of srb were randomly picked and isolated from the highest serial dilution that showed growth (i.e. 10(8)). repetitive enterobacterial palindromic polymerase chain reaction and whole cell protein prof ... | 2007 | 17440719 |
diversity of substrate utilization and growth characteristics of sulfate-reducing bacteria isolated from estuarine sediment in japan. | two different isolation methods, the dilution colony-counting method (colony-isolation) and enrichment culture, were used to isolate sulfate-reducing bacteria (srbs) from estuarine sediment in japan. lactate was used as an electron donor for colony-isolation, and lactate or propionate was used for enrichment culture. all isolates were classified into six different phylogenetic groups according to the 16s rrna gene-based analysis. the closest relatives of the colony-isolates (12 strains) were spe ... | 2007 | 17575452 |
phylogenetic diversity of sulfate-reducing prokaryotes in active deep-sea hydrothermal vent chimney structures. | the phylogenetic diversity of sulfate-reducing prokaryotes occurring in active deep-sea hydrothermal vent chimney structures was characterized based on the deduced amino acid sequence analysis of the polymerase chain reaction-amplified dissimilatory sulfite reductase (dsr) gene. the dsr genes were successfully amplified from microbial assemblages of the chimney structures, derived from three geographically and geologically distinct deep-sea hydrothermal systems in the central indian ridge (cir), ... | 2004 | 15033233 |
diversity of sulfate-reducing bacteria inhabiting the rhizosphere of phragmites australis in lake velencei (hungary) revealed by a combined cultivation-based and molecular approach. | the community structure of sulfate-reducing bacteria (srb) associated with reed (phragmites australis) rhizosphere in lake velencei (hungary) was investigated by using cultivation-based and molecular methods. the cultivation methods were restricted to recover lactate-utilizing species with the exclusion of desulfobacter and some desulfobacterium species presumably not being dominant members of the examined community. the most-probable-number (mpn) estimations of lactate-utilizing srb showed that ... | 2008 | 18066486 |
competition and coexistence of sulfate-reducing bacteria, acetogens and methanogens in a lab-scale anaerobic bioreactor as affected by changing substrate to sulfate ratio. | the microbial population structure and function of natural anaerobic communities maintained in lab-scale continuously stirred tank reactors at different lactate to sulfate ratios and in the absence of sulfate were analyzed using an integrated approach of molecular techniques and chemical analysis. the population structure, determined by denaturing gradient gel electrophoresis and by the use of oligonucleotide probes, was linked to the functional changes in the reactors. at the influent lactate t ... | 2008 | 18305937 |
contributions of fermentative acidogenic bacteria and sulfate-reducing bacteria to lactate degradation and sulfate reduction. | the roles of fermentative acidogenic bacteria and sulfate-reducing bacteria (srb) in lactate degradation and sulfate reduction in a sulfidogenic bioreactor were investigated by traditional chemical monitoring and culture-independent methods. a continuously stirred tank reactor fed with synthetic wastewater containing lactate and so(2-)(4) at 35 degrees c, 10h of hydraulic retention time was used. the results showed that sulfate removal efficiency reached 99%, and sulfide and acetate were the mai ... | 2008 | 18331751 |
evaluation of the sulfate-reducing bacterial population associated with stored swine slurry. | hydrogen sulfide, produced by sulfate-reducing bacteria (srb), is one of the most potent malodors emitted from anaerobic swine waste storage systems. however, little is known about the prevalence and diversity of srb in those systems. the goals of this study were to evaluate the srb population in swine manure storage systems and to develop quantitative, real-time pcr (qrt-pcr) assays to target four of the srb groups. dissimilatory sulfite reductase (dsr) gene sequences were obtained from swine s ... | 2008 | 18457964 |
are methylmercury concentrations in the wetlands of kejimkujik national park, nova scotia, canada, dependent on geology? | in the relatively pristine ecosystem in kejimkujik park, nova scotia, methylmercury (mehg) concentrations in loons, gavia immer, are among the highest recorded anywhere in the world. this study investigated the influence of bedrock lithology on mehg concentrations in wetlands. twenty-five different wetland field sites were sampled over four different bedrock lithologies; kejimkujik monzogranite, black sulfidic slate, gray slate, and greywacke. soil samples were analyzed for ethylmercury (ethg), ... | 2003 | 14674530 |
development and comparison of sybr green quantitative real-time pcr assays for detection and enumeration of sulfate-reducing bacteria in stored swine manure. | to develop and evaluate primer sets targeted to the dissimilatory sulfite reductase gene (dsra) for use in quantitative real-time pcr detection of sulfate-reducing bacteria (srb) in stored swine manure. | 2008 | 19120660 |
characterization and activity studies of highly heavy metal resistant sulphate-reducing bacteria to be used in acid mine drainage decontamination. | biological treatment with sulphate-reducing bacteria (srb) has been considered as the most promising alternative for acid mine drainage (amd) decontamination. normally, these wastewaters contain high concentrations of sulphate and heavy metals, so the search for srb highly resistant to metals is extremely important for the development of a bioremediation technology. a srb consortium resistant to high concentrations of heavy metals (fe, cu and zn), similar to those typically present in amd, was o ... | 2009 | 19135795 |
molecular diversity of sulfate-reducing bacteria from two different continental margin habitats. | this study examined the natural diversity and distributions of sulfate-reducing bacteria along a natural carbon gradient extending down the shelf-slope transition zone of the eastern pacific continental margin. dissimilatory (bi)sulfite reductase gene sequences (dsrab) were pcr amplified and cloned from five different sampling sites, each at a discrete depth, from two different margin systems, one off the pacific coast of mexico and another off the coast of washington state. a total of 1,762 clo ... | 2003 | 14532064 |
diversity of culturable sulfidogenic bacteria in two oil-water separation tanks in the north-eastern oil fields of india. | sulfidogenic communities in the production waters of onshore oil fields in north-eastern india were examined using a culturing approach. production water samples were inoculated into medium selective for sulfate reducing bacteria (srb) and thiosulfate reducing bacteria (trb). the total number of viable sulfidogenic microorganisms in the samples obtained from the two production water tanks was approximately 10(5) mpn ml(-1) (most probable number per ml). most of the isolates were thermo-tolerant ... | 2010 | 19427389 |
growth and chemosensory behavior of sulfate-reducing bacteria in oxygen-sulfide gradients. | growth and chemotactic behavior in oxic-anoxic gradients were studied with two freshwater and four marine strains of sulfate-reducing bacteria related to the genera desulfovibrio, desulfomicrobium or desulfobulbus. cells were grown in oxygen-sulfide counter-gradients within tubes filled with agar-solidified medium. the immobilized cells grew mainly in the anoxic zone, revealing a peak below the oxic-anoxic interface. all tested strains survived exposure to air for 8 h and all were capable of oxy ... | 2002 | 19709210 |
sulfate-reducing bacterial community response to carbon source amendments in contaminated aquifer microcosms. | abstract microbial sulfate reduction is an important metabolic activity in many reduced habitats. however, little is known about the sulfate-reducing communities inhabiting petroleum hydrocarbon (phc)-contaminated freshwater aquifer sediments. the purpose of this study was to identify the groups of sulfate-reducing bacteria (srb) selectively stimulated when sediment from a phc-contaminated freshwater aquifer was incubated in sulfate-reducing aquifer microcosms that were amended with specific car ... | 2002 | 19709270 |
sulfate-reducing bacterial community structure and their contribution to carbon mineralization in a wastewater biofilm growing under microaerophilic conditions. | the community structure of sulfate-reducing bacteria (srb) and the contribution of srb to carbon mineralization in a wastewater biofilm growing under microaerophilic conditions were investigated by combining molecular techniques, molybdate inhibition batch experiments, and microelectrode measurements. a 16s rdna clone library of bacteria populations was constructed from the biofilm sample. the 102 clones analyzed were grouped into 53 operational taxonomic units (otus), where the clone distributi ... | 2003 | 12879306 |
comparisons of subgingival microbial profiles of refractory periodontitis, severe periodontitis, and periodontal health using the human oral microbe identification microarray. | this study compared the subgingival microbiota of subjects with refractory periodontitis (rp) to those in subjects with treatable periodontitis (grs = good responders) or periodontal health (ph) using the human oral microbe identification microarray (homim). | 2009 | 19722792 |
effect of sulfate absence and nitrate addition on bacterial community in a sulfidogenic bioreactor. | the characteristics and behavior of sulfate-reducing bacteria (srb), methane-producing bacteria (mpb) and denitrifying bacteria (db) were investigated by polymerase chain reaction (pcr) based methods under the transitory sulfate absence or nitrate addition conditions in a sulfidogenic continuously stirred tank reactor. the bioreactor started-up feeding with 4000 mg l(-1) cod (lactate) and 2000 mg l(-1) sulfate (so(4)(2-)). the sulfate removal efficiency reached 3.84 g l(-1)d(-1) when the activat ... | 2009 | 19735978 |
reduction of net mercury methylation by iron in desulfobulbus propionicus (1pr3) cultures: implications for engineered wetlands. | although one potential drawback of wetland construction and restoration is the formation of monomethylmercury, it may be possible to decrease net mercury methylation with the use of an appropriate sediment amendment. using pure cultures of the sulfate-reducing bacterium desulfobulbus propionicus (1pr3), we tested the hypothesis that adding ferrous iron to sulfidic wetland sediments decreases mercury solubility and bioavailability and, therefore, net methylation. in sediment-free cultures, net me ... | 2003 | 12875409 |
the distribution and activity of sulphate reducing bacteria in estuarine and coastal marine sediments. | sulphate-reducing bacteria (srb) play a vital role both the carbon and sulphur cycles and thus are extremely important components of the global microbial community. however, it is clear that the ecology, the distribution and activity of different srb groups is poorly understood. probing of rrna suggests that different sediments have distinctly different patterns of srb with complex factors controlling the activity of these organisms. the linking of community structure and function using sediment ... | 2002 | 12448716 |
microbial community analysis of anodes from sediment microbial fuel cells powered by rhizodeposits of living rice plants. | by placing the anode of a sediment microbial fuel cell (smfc) in the rhizosphere of a rice plant, root-excreted rhizodeposits can be microbially oxidized with concomitant current generation. here, various molecular techniques were used to characterize the composition of bacterial and archaeal communities on such anodes, as influenced by electrical circuitry, sediment matrix, and the presence of plants. closed-circuit anodes in potting soil were enriched with desulfobulbus-like species, members o ... | 2010 | 20097806 |
desulfobulbus mediterraneus sp. nov., a sulfate-reducing bacterium growing on mono- and disaccharides. | a new sulfate-reducing bacterium, strain 86fs1, was isolated from a deep-sea sediment in the western mediterranean sea with sodium lactate as electron and carbon source. cells were ovoid, gram-negative and motile. strain 86fs1 contained b- and c-type cytochromes. the organism was able to utilize propionate, pyruvate, lactate, succinate, fumarate, malate, alanine, primary alcohols (c(2)-c(5)), and mono- and disaccharides (glucose, fructose, galactose, ribose, sucrose, cellobiose, lactose) as elec ... | 2002 | 12029392 |
diversity of dissimilatory sulfite reductase genes (dsrab) in a salt marsh impacted by long-term acid mine drainage. | sulfate-reducing bacteria (srb) play a major role in the coupled biogeochemical cycling of sulfur and chalcophilic metal(loid)s. by implication, they can exert a strong influence on the speciation and mobility of multiple metal(loid) contaminants. in this study, we combined dsrab gene sequencing and sulfur isotopic profiling to identify the phylogeny and distribution of srb and to assess their metabolic activity in salt marsh sediments exposed to acid mine drainage (amd) for over 100 years. reco ... | 2010 | 20472728 |
desulfomusa hansenii gen. nov., sp. nov., a novel marine propionate-degrading, sulfate-reducing bacterium isolated from zostera marina roots. | the physiology and phylogeny of a novel sulfate-reducing bacterium, isolated from surface-sterilized roots of the marine macrophyte zostera marina, are presented. the strain, designated p1t, was enriched and isolated in defined oxygen-free, bicarbonate-buffered, iron-reduced seawater medium with propionate as sole carbon source and electron donor and sulfate as electron acceptor. strain p1t had a rod-shaped, slightly curved cell morphology and was motile by means of a single polar flagellum. cel ... | 2001 | 11760947 |
mercury methylation in sphagnum moss mats and its association with sulfate-reducing bacteria in an acidic adirondack forest lake wetland. | processes leading to the bioaccumulation of methylmercury (mehg) in northern wetlands are largely unknown. we have studied various ecological niches within a remote, acidic forested lake ecosystem in the southwestern adirondacks, ny, to discover that mats comprised of sphagnum moss were a hot spot for mercury (hg) and mehg accumulation (190.5 and 18.6 ng g⁻¹ dw, respectively). furthermore, significantly higher potential methylation rates were measured in sphagnum mats as compared with other site ... | 2010 | 20955196 |
the influence of sulfide on solid-phase mercury bioavailability for methylation by pure cultures of desulfobulbus propionicus (1pr3). | to help understand the mechanism and control of hg uptake in hg-methylating bacteria, we investigated the effect of sulfide on hg methylation by pure cultures of the sulfate-reducing bacterium desulfobulbus propionicus (1pr3). our previous research in natural sediments has suggested that hg methylation occurs most rapidly when sulfide concentrations favor formation of neutral dissolved hg-s species. in this study, the chemical speciation of hg in culture media was manipulated by growing d. propi ... | 2001 | 11351996 |
abundance and diversity of biofilms in natural and artificial aquifers of the äspö hard rock laboratory, sweden. | six cores were drilled and retrieved from 186-m depth in the äspö hard rock laboratory (hrl) tunnel to investigate whether indigenous biofilms develop on fracture surfaces in groundwater-conducting aquifers in granitic rock. a clone library was constructed from fracture surface material (fsm), for community composition analysis. quantitative polymerase chain reaction (qpcr) was applied to quantify gene copies using the 16s rrna gene for domain bacteria and the adenosine-phosphosulfate reductase ... | 2010 | 21132427 |
structure of microbial communities and hydrocarbon-dependent sulfate reduction in the anoxic layer of a polluted microbial mat. | the bacterial communities in the anoxic layer of a heavily polluted microbial mat and their growth on hydrocarbons under sulfate-reducing conditions were investigated. microbial communities were dominated by members of alphaproteobacteria (27% of the total rrna), planctomycetes (21.1%) and sulfate-reducing bacteria (srb: 17.5%). 16s rrna cloning revealed sequences beloning to the same bacterial groups with srb affiliated to the genera desulfobulbus, desulfocapsa, desulfomicrobium, desulfobacteri ... | 2010 | 21194714 |
bacterial diversity and community composition in the chemocline of the meromictic alpine lake cadagno as revealed by 16s rdna analysis. | using different techniques of molecular biology we investigated the bacterial diversity of the chemocline of the meromictic lake cadagno. cloning of a total community 16s rdna pcr product and subsequent screening with a combination of amplified ribosomal dna restriction analysis and temporal temperature gradient gel electrophoresis (ttge) analysis revealed that 30 of 47 randomly selected clones were unique. partial sequencing and comparative analysis indicated a high bacterial diversity dominate ... | 2000 | 10640670 |
rna-oligonucleotide quantification technique (roqt) for the enumeration of uncultivated bacterial species in subgingival biofilms. | approximately 35% of the species present in subgingival biofilms are as yet uncultivated, so their role in periodontal pathogenesis is unknown. the aim of the present study was to develop a high throughput method to quantify a wide range of cultivated and uncultivated taxa in subgingival biofilm samples associated with periodontal disease or health. oligonucleotides targeting the 16s ribosomal dna gene were designed, synthesized and labeled with digoxigenin. these probes were hybridized with the ... | 2011 | 21375703 |
sulfate-reducing bacteria in rice field soil and on rice roots. | rice plants that were grown in flooded rice soil microcosms were examined for their ability to exhibit sulfate reducing activity. washed excised rice roots showed sulfate reduction potential when incubated in anaerobic medium indicating the presence of sulfate-reducing bacteria. rice plants, that were incubated in a double-chamber (phylloshpere and rhizosphere separated), showed potential sulfate reduction rates in the anoxic rhizosphere compartment. these rates decreased when oxygen was allowed ... | 1999 | 10390878 |
phylogenetic and physiological diversity of sulphate-reducing bacteria isolated from a salt marsh sediment. | the phylogenetic and physiological diversity of sulphate-reducing bacteria inhabiting a salt marsh rhizosphere were investigated. sulphate-reducing bacteria were isolated from a salt marsh rhizosphere using enrichment cultures with electron donors thought to be prevalent in the rhizosphere of spartina alterniflora. the relationship between phylogeny and nutritional characteristics of 10 strains was investigated. none of the isolates had 16s rrna sequences identical to other delta subclass sulpha ... | 1998 | 9924824 |
dynamic microbial response of sulfidogenic wastewater biofilm to nitrate. | nitrate is one of the chemicals often added to wastewater to control hydrogen sulfide production by sulfate-reducing bacteria (srb). while the effect of nitrate in various srb pure cultures is well documented, the effect observed in mixed microbial communities is not consistent. this study investigates the response of mixed srb communities to nitrate, by examining the changes in activity and community composition of sulfidogenic wastewater biofilm over a 10-day period with 10 mmol l(-1) nitrate ... | 2011 | 21611797 |
diversity and composition of sulfate- and sulfite-reducing prokaryotes as affected by marine-freshwater gradient and sulfate availability. | sulfate- and sulfite-reducing prokaryotes (ssrp) communities play a key role in both sulfur and carbon cycles. in estuarine ecosystems, sulfate concentrations change with tides and could be limited in tidal freshwater reach or deep sediments. in a subtropical estuary of northern taiwan in december 2007, we examined the compositional changes of ssrp communities. we examined three sites: from the lower estuarine brackish-water reach (site gr and mangrove vegetation site, gm) to the upper estuarine ... | 2011 | 21785985 |
desulfobulbus rhabdoformis sp. nov., a sulfate reducer from a water-oil separation system. | a mesophilic, gram-negative, rod-shaped, marine, propionate-oxidizing sulfate reducer (strain m16t) was isolated from a water-oil separation system on a north sea oil platform. the optimum conditions for growth were 31 degrees c, ph 6.8-7.2 and 1.5-2.0% (w/v) nacl and 0.1-0.3% (w/v) mgcl2.6h2o in the medium. the growth yield with sulfate was 4.6 g cell biomass (mol propionate oxidized)-1. strain m16t is nutritionally related to members of the genus desulfobulbus, but differs in that it has no vi ... | 1998 | 9731286 |
elemental sulfur and thiosulfate disproportionation by desulfocapsa sulfoexigens sp. nov., a new anaerobic bacterium isolated from marine surface sediment. | a mesophilic, anaerobic, gram-negative bacterium, strain sb164p1, was enriched and isolated from oxidized marine surface sediment with elemental sulfur as the sole energy substrate in the presence of ferrihydrite. elemental sulfur was disproportionated to hydrogen sulfide and sulfate. growth was observed exclusively in the presence of a hydrogen sulfide scavenger, e.g., ferrihydrite. in the absence of a scavenger, sulfide and sulfate production were observed but no growth occurred. strain sb164p ... | 1998 | 9435068 |
phylogenetic positions of desulfofustis glycolicus gen. nov., sp. nov., and syntrophobotulus glycolicus gen. nov., sp. nov., two new strict anaerobes growing with glycolic acid. | the glycolate-oxidizing, sulfate-reducing bacterium strain perglys and the syntrophically glycolate-oxidizing bacterium strain flglyr were studied with respect to their phylogenetic relationships on the basis of in vitro amplification and direct sequencing of 16s rrna-encoding dna. strain perglys clustered with representatives of the delta subclass of the class proteobacteria, close to "desulforhopalus vacuolatus" but sufficiently distinct to preclude its assignment to this genus. these organism ... | 1996 | 8863436 |
on the relationship between sialomucin and sulfomucin expression and hydrogenotrophic microbes in the human colonic mucosa. | the colonic mucus layer is comprised primarily of acidomucins, which provide viscous properties and can be broadly classified into sialomucins or sulfomucins based on the presence of terminating sialic acid or sulfate groups. differences in acidomucin chemotypes have been observed in diseases such as colorectal cancer and inflammatory bowel disease, and variation in sialo- and sulfomucin content may influence microbial colonization. for example, sulfate derived from sulfomucin degradation may pr ... | 2011 | 21931721 |
s cycling: characterization of natural communities of sulfate-reducing bacteria by 16s rrna sequence comparisons | past studies of microbial communities responsible for geochemical transformations have been limited by an inability to representatively cultivate, and then identify, the constituent members. ribosomal rna sequences, particularly 16s-like rrnas, provide a measure of phylogenetic relationship that can now be used to examine the structure and diversity of microbial communities. sulfate-reducing bacteria (srb) play an important role in the sulfur cycle and the terminal mineralization of organic matt ... | 1996 | 8849423 |
sulfate reduction by a syntrophic propionate-oxidizing bacterium. | the syntrophic propionate-oxidizing bacterium mpob was able to grow in the absence of methanogens by coupling the oxidation of propionate to the reduction of sulfate. growth on propionate plus sulfate was very slow (mu = 0.024 day-1). an average growth yield was found of 1.5 g (dry weight) per mol of propionate. mpob grew even slower than other sulfate-reducing syntrophic propionate-oxidizing bacteria. the growth rates and yields of strict sulfate-reducing bacteria (desulfobulbus sp.) grown on p ... | 1995 | 8821784 |
oxidation of short-chain fatty acids by sulfate-reducing bacteria in freshwater and in marine sediments. | colony counts of acetate-, propionate- and l-lactate-oxidizing sulfate-reducing bacteria in marine sediments were made. the vertical distribution of these organisms were equal for the three types considered. the highest numbers were found just beneath the border of aerobic and anaerobic layers. anaerobic mineralization of acetate, propionate and l-lactate was studied in the presence and in the absence of sulfate. in freshwater and in marine sediments, acetate and propionate were oxidized complet ... | 1981 | 7212933 |
isolation of succinate dehydrogenase from desulfobulbus elongatus, a propionate oxidizing, sulfate reducing bacterium. | succinate dehydrogenase was purified from the particulate fraction of desulfobulbus. the enzyme catalyzed both fumarate reduction and succinate oxidation but the rate of fumarate reduction was 8-times less than that of succinate oxidation. quantitative analysis showed the presence of 1 mol of covalently bound flavin and 1 mol of cytochrome b per mol of succinate dehydrogenase. the enzyme contained three subunits with molecular mass 68.5, 27.5 and 22 kda. epr spectroscopy indicated the presence o ... | 1987 | 3582662 |
5'-methylbenzimidazolyl-cobamides are the corrinoids from some sulfate-reducing and sulfur-metabolizing bacteria. | the sulfate-reducing bacteria desulfobacterium autotrophicum, desulfobulbus propionicus and archaeoglobus fulgidus (vc-16) and the sulfur-metabolizing archaebacteria desulfurolobus ambivalens and thermoplasma acidophilum were found to contain considerable amounts of corrinoids, that were isolated and crystallized in their co beta-cyano form. in three other sulfur-metabolizing archaebacteria, thermoproteus neutrophilus, pyrodictium occultum and staphylothermus marinus significant amounts of corri ... | 1988 | 3416881 |
protonmotive force in freshwater sulfate-reducing bacteria, and its role in sulfate accumulation in desulfobulbus propionicus. | the protonmotive force in several sulfate-reducing bacteria has been determined by means of radiolabelled membrane-permeant probes (tetraphenylphosphonium cation, tpp+, for delta psi, and benzoate for delta ph). in six of ten freshwater strains tested only the ph gradient could be determined, while the membrane potential was not accessible due to nonspecific binding of tpp+. the protonmotive force of the other four strains was between -110 and -155 mv, composed of a membrane potential of -80 to ... | 1992 | 1332637 |
a study of the relative dominance of selected anaerobic sulfate-reducing bacteria in a continuous bioreactor by fluorescence in situ hybridization. | the diversity and the community structure of sulfate-reducing bacteria (srb) in an anaerobic continuous bioreactor used for treatment of a sulfate-containing wastewater were investigated by fluorescence in situ hybridization. hybridization to the 16s rrna probe eub338 for the domain bacteria was performed, followed by a nonsense probe non338 as a control for nonspecific staining. sulfate-reducing consortia were identified by using five nominally genus-specific probes (srb129 for desulfobacter, s ... | 2007 | 16941240 |
treatment of dye works wastewater using anaerobic-oxic biological filter reactor packed with carbon fibre and aerated with micro-bubbles. | a new anaerobic-oxic biological filter reactor, which was packed with carbon fibre and aerated with micro-bubbles, was proposed. the reactor performance was examined using dye works wastewater compared with the activated sludge reactor. effluent ss from the experimental reactor was significantly lower than that from the activated sludge reactor, and transparency was higher. temperatures of the activated sludge reactor were over 35 degrees c and doc removal ratios were 40-80% depending on the inf ... | 2006 | 16862785 |
desulfobulbus japonicus sp. nov., a novel gram-negative propionate-oxidizing, sulfate-reducing bacterium isolated from an estuarine sediment in japan. | two strictly anaerobic, mesophilic, sulfate-reducing bacterial strains, pro1(t) and pro16, were isolated from an estuarine sediment in the sea of japan of the japanese islands and were characterized by phenotypic and phylogenetic methods. strains pro1(t) and pro16 had almost the same physiological and chemotaxonomic characteristics. cells of both strains were gram-negative, motile, non-spore-forming rods. catalase activity was not detected. the optimum nacl concentration for growth was 3.0 % (w/ ... | 2007 | 17392218 |
genotypic distribution of an indigenous model microorganism along an estuarine gradient. | using the genus desulfobulbus as an indigenous model, microbial distribution along an estuarine gradient was investigated. denaturing gradient gel electrophoresis analysis indicated a sequential change in desulfobulbus genotypes along the estuary with marine, brackish and freshwater genotypes detected. this differential distribution was significantly correlated with porewater concentrations of chloride, sulphate and nitrate. temporal analysis indicated that there was a shift in the whole desulfo ... | 2007 | 17850329 |
characterization of methyl mercury in dental wastewater and correlation with sulfate-reducing bacterial dna. | dental wastewater (dww) was collected over two months from a 12-chair clinic and a single-chair office to identify conditions that may affect hg methylation. dww was settled for 24 h and samples were collected from the top and bottom of the supernatant to simulate a range of particles that may escape in-line traps. total hg spanned 5 orders of magnitude (0.02-5000 microm), following a log-normal distribution with p10, p50, and p90 concentration values of 0.24, 31 and 4000 microm, respectively; t ... | 2008 | 18497123 |
the microorganism community of pentachlorophenol (pcp)-degrading coupled granules. | coupled granules are self-immobilized aggregates of microorganisms under micro aerobic conditions, which have the dissolved oxygen (do) level of 0.6 mg.l(-1). the effects of do concentration on pentachlorophenol (pcp) reduction and its microbial community were investigated in a coupled anaerobic and aerobic reactor. both the diversity and the dynamicity of the eubacteria and archaea community, which were responsible for pcp degradation, were evaluated by means of amplification by polymerase chai ... | 2009 | 19273898 |
use of 16s rrna-targeted oligonucleotide probes to investigate function and phylogeny of sulphate-reducing bacteria and methanogenic archaea in a uk estuary. | abstract sulphate-reducing bacteria (srb) and methanogenic archaea (ma) are important anaerobic terminal oxidisers of organic matter. however, we have little knowledge about the distribution and types of srb and ma in the environment or the functional role they play in situ. here we have utilised sediment slurry microcosms amended with ecologically significant substrates, including acetate and hydrogen, and specific functional inhibitors, to identify the important srb and ma groups in two contra ... | 2003 | 19719617 |
species-specific stable isotope fractionation of mercury during hg(ii) methylation by an anaerobic bacteria (desulfobulbus propionicus) under dark conditions. | this work reports the first results on the stable isotope fractionation of hg during methylation by anaerobic bacteria under dark conditions. the gc-mc-icpms methodology employed is capable of simultaneously measuring the species-specific isotopic composition of different hg species within the same sample. we have studied hg isotopic fractionation caused by methylation of hg(ii) standard reference material nist-3133 in the presence of the pure bacterial strain desulfobulbus propionicus mud10 (ds ... | 2009 | 19924895 |
evolutionary divergence and biogeography of sympatric niche-differentiated bacterial populations. | using multiple lines of evidence from denaturing gradient gel electrophoresis, environmental sequences and taqman quantitative pcr assays targeting a functional gene for sulfate respiration (dsr) affiliated with the geochemically important genus desulfobulbus, we revealed strongly restricted distributions of specific genotypes and populations correlated with sampling position along an estuarine gradient free of dispersal barriers. evidence of evolutionary divergence of populations was provided b ... | 2010 | 20054357 |
diversity of microbes and potential exoelectrogenic bacteria on anode surface in microbial fuel cells. | single-chamber microbial fuel cells (mfcs), inoculated with anaerobic sludge and continuously run with two kinds of organic wastewater influents, were systemically investigated. the diversity of microbes, determined by 16s rdna analysis, was analyzed on three anodes under different conditions. one anode was in a closed circuit in synthetic wastewater containing glucose. the other two anodes, in open or closed circuits, were fed effluent from an anaerobic reactor treating starch wastewater. the c ... | 2010 | 20339216 |
identification of the dominant sulfate-reducing bacterial partner of anaerobic methanotrophs of the anme-2 clade. | summary the anaerobic oxidation of methane (aom) with sulfate as terminal electron acceptor is mediated by consortia of methanotrophic archaea (anme) and sulfate-reducing bacteria (srb). whereas three clades of anme have been repeatedly studied with respect to phylogeny, key genes and genomic capabilities, little is known about their sulfate-reducing partner. in order to identify the partner of anaerobic methanotrophs of the anme-2 clade, bacterial 16s rrna gene libraries were constructed from c ... | 2010 | 20629706 |
sulfate-reducing bacteria in a denitrification reactor packed with wood as a carbon source. | a denitrification reactor packed with wood as a carbon source was operated using synthetic inorganic wastewater. the maximum denitrification rate was 62.4 g-no(3)(-)/m(3)/day at hrt of 24 h. the nitrate removal continued after 1500 days. the denitrification efficiency was assumed to enhance sulfur denitrification via wood degradation by sulfate reduction. the achieved sulfate reduction rate was 468 mg-so(4)(2-)/kg-dry weight wood/day after 419 days of operation. the sulfate reduction rate in the ... | 2010 | 21071213 |
mercury species of sediment and fish in freshwater fish ponds around the pearl river delta, pr china: human health risk assessment. | this study investigated total mercury (thg) and methylmercury (mehg) concentrations in five species of freshwater fish and their associated fish pond sediments collected from 18 freshwater fish ponds around the pearl river delta (prd). the concentrations of thg and mehg in fish pond surface sediments were 33.1-386 ng g(-1) dry wt and 0.18-1.25 ng g(-1) dry wt, respectively. the age of ponds affected the surface sediment mehg concentration. the vertical distribution of mehg in sediment cores show ... | 2011 | 21272914 |
complete genome sequence of desulfobulbus propionicus type strain (1pr3). | desulfobulbus propionicus widdel 1981 is the type species of the genus desulfobulbus, which belongs to the family desulfobulbaceae. the species is of interest because of its great implication in the sulfur cycle in aquatic sediments, its large substrate spectrum and a broad versatility in using various fermentation pathways. the species was the first example of a pure culture known to disproportionate elemental sulfur to sulfate and sulfide. this is the first completed genome sequence of a membe ... | 2011 | 21475592 |
microbial community succession in a bioreactor modeling a souring low-temperature oil reservoir subjected to nitrate injection. | injection of up-flow packed-bed bioreactors with excess volatile fatty acids and limiting concentrations of nitrate and sulfate gave complete reduction of nitrate from 0 to 5.5 cm and complete or near-complete reduction of sulfate from 3.2 to 11.5 cm along the bioreactor flow path. most of the biomass (85%) and most of the genes for nitrate reduction (narg, 96%; napa, 99%) and for sulfate reduction (dsrb, 91%) were present near the inlet (0-5.5 cm) of the 37-cm-long bioreactor. microbial communi ... | 2011 | 21538114 |
Haloalkaliphilic heterotrophic sulfate-reducing bacteria from soda lakes and description of Desulfonatronobacter acidovorans gen. nov., sp. nov., and Desulfobulbus alkaliphilus sp. nov. | Two novel types of heterotrophic sulfate-reducing bacteria (SRB) were isolated from anoxic sediments of hypersaline soda lakes in Kulunda Steppe (Altai, Russia) using propionate as energy and carbon source. Strain APT2T was enriched and isolated with thiosulfate and strains APS1T andASS1 with sulfate as electron acceptor. APT2T was a short rod motile with a single subpolar flagellum, while APS1T/ASS1 were lemon-shaped oval rods motile with a single polar flagellum and also producing multiple th ... | 2011 | 22039002 |
identification of the dominant sulfate-reducing bacterial partner of anaerobic methanotrophs of the anme-2 clade. | the anaerobic oxidation of methane (aom) with sulfate as terminal electron acceptor is mediated by consortia of methanotrophic archaea (anme) and sulfate-reducing bacteria (srb). whereas three clades of anme have been repeatedly studied with respect to phylogeny, key genes and genomic capabilities, little is known about their sulfate-reducing partner. in order to identify the partner of anaerobic methanotrophs of the anme-2 clade, bacterial 16s rrna gene libraries were constructed from cultures ... | 2010 | 21966923 |
Genotypic Distribution of a Specialist Model Microorganism, Methanosaeta, along an Estuarine Gradient: Does Metabolic Restriction Limit Niche Differentiation Potential? | A reductionist ecological approach of using a model genus was adopted in order to understand how microbial community structure is driven by metabolic properties. The distribution along an estuarine gradient of the highly specialised genus Methanosaeta was investigated and compared to the previously determined distribution of the more metabolically flexible Desulfobulbus. Methanosaeta genotypic distribution along the Colne estuary (Essex, UK) was determined by DNA- and RNA-based denaturing gradie ... | 2011 | 22183047 |
contrasting patterns of niche partitioning between two anaerobic terminal oxidizers of organic matter. | understanding the ecological principles underlying the structure and function of microbial communities remains an important goal for microbial ecology. we examined two biogeochemically important taxa, the sulfate-reducing bacterial genus, desulfobulbus, and the methanogenic archaeal genus, methanosaeta, to compare and contrast niche partitioning by these two taxa that are ecologically linked as anaerobic terminal oxidizers of organic material. an observational approach utilizing functional gene ... | 2011 | 22113373 |