| comparative analysis of methane-oxidizing archaea and sulfate-reducing bacteria in anoxic marine sediments. | the oxidation of methane in anoxic marine sediments is thought to be mediated by a consortium of methane-consuming archaea and sulfate-reducing bacteria. in this study, we compared results of rrna gene (rdna) surveys and lipid analyses of archaea and bacteria associated with methane seep sediments from several different sites on the californian continental margin. two distinct archaeal lineages (anme-1 and anme-2), peripherally related to the order methanosarcinales, were consistently associated ... | 2001 | 11282650 |
| congruent phylogenies of most common small-subunit rrna and dissimilatory sulfite reductase gene sequences retrieved from estuarine sediments. | the diversity of sulfate-reducing bacteria (srb) in brackish sediment was investigated using small-subunit rrna and dissimilatory sulfite reductase (dsr) gene clone libraries and cultivation. the phylogenetic affiliation of the most commonly retrieved clones for both genes was strikingly similar and produced desulfosarcina variabilis-like sequences from the inoculum but desulfomicrobium baculatum-like sequences from a high dilution in natural media. related organisms were subsequently cultivated ... | 2001 | 11425760 |
| biogeochemical and molecular signatures of anaerobic methane oxidation in a marine sediment. | anaerobic methane oxidation was investigated in 6-m-long cores of marine sediment from aarhus bay, denmark. measured concentration profiles for methane and sulfate, as well as in situ rates determined with isotope tracers, indicated that there was a narrow zone of anaerobic methane oxidation about 150 cm below the sediment surface. methane could account for 52% of the electron donor requirement for the peak sulfate reduction rate detected in the sulfate-methane transition zone. molecular signatu ... | 2001 | 11282617 |
| diversity and community structure within anoxic sediment from marine salinity meromictic lakes and a coastal meromictic marine basin, vestfold hilds, eastern antarctica. | 16s rdna clone library analysis was used to examine the biodiversity and community structure within anoxic sediments of several marine-type salinity meromictic lakes and a coastal marine basin located in the vestfolds hills area of eastern antarctica. from 69 to 130 (555 total) 16s rdna clones were analysed from each sediment sample, and restriction fragment length polymorphism (rflp) and sequence analysis grouped the clones into 202 distinct phylotypes (a clone group with sequence similarity of ... | 2000 | 11220308 |
| [methane production by the sulfate-reducing bacterium desulfosarcina variabilis]. | the sulfate-reducing bacterium desulfosarcina variabilis vkm b-1694 was found to produce up to 1.62 mumol methane per mg protein when grown on different substrates. the role of methanogenesis and the physicochemical factors determining this process in sulfate-reducing bacteria are discussed. | 2000 | 10920802 |
| community structure, cellular rrna content, and activity of sulfate-reducing bacteria in marine arctic sediments. | the community structure of sulfate-reducing bacteria (srb) of a marine arctic sediment (smeerenburgfjorden, svalbard) was characterized by both fluorescence in situ hybridization (fish) and rrna slot blot hybridization by using group- and genus-specific 16s rrna-targeted oligonucleotide probes. the srb community was dominated by members of the desulfosarcina-desulfococcus group. this group accounted for up to 73% of the srb detected and up to 70% of the srb rrna detected. the predominance was sh ... | 2000 | 10919825 |
| 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 |
| 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 |
| isolation and characterization of a sulfate-reducing bacterium that anaerobically degrades alkanes. | an alkane-degrading, sulfate-reducing bacterial strain, ak-01, was isolated from an estuarine sediment with a history of chronic petroleum contamination. the bacterium is a short, nonmotile, non-spore-forming, gram-negative rod. it is mesophilic and grows optimally at ph 6.9 to 7.0 and at an nacl concentration of 1%. formate, fatty acids (c4 to c16) and hydrogen were readily utilized as electron donors. sulfate, sulfite, and thiosulfate were used as electron acceptors, but sulfur, nitrite, and n ... | 1999 | 10388691 |
| desulfobacca acetoxidans gen. nov., sp. nov., a novel acetate-degrading sulfate reducer isolated from sulfidogenic granular sludge. | a mesophilic sulfate reducer, strain asrb2t, was isolated with acetate as sole carbon and energy source from granular sludge of a laboratory-scale upflow anaerobic sludge bed reactor fed with acetate and sulfate. the bacterium was oval-shaped, 1.3 x 1.9-2.2 microns, non-motile and gram-negative. optimum growth with acetate occurred around 37 degrees c in freshwater medium (doubling time: 1.7-2.2 d). enzyme studies indicated that acetate was oxidized via the carbon monoxide dehydrogenase pathway. ... | 1999 | 10319454 |
| anaerobic oxidation of o-xylene, m-xylene, and homologous alkylbenzenes by new types of sulfate-reducing bacteria. | various alkylbenzenes were depleted during growth of an anaerobic, sulfate-reducing enrichment culture with crude oil as the only source of organic substrates. from this culture, two new types of mesophilic, rod-shaped sulfate-reducing bacteria, strains oxys1 and mxys1, were isolated with o-xylene and m-xylene, respectively, as organic substrates. sequence analyses of 16s rrna genes revealed that the isolates affiliated with known completely oxidizing sulfate-reducing bacteria of the delta subcl ... | 1999 | 10049854 |
| seasonal changes in the relative abundance of uncultivated sulfate-reducing bacteria in a salt marsh sediment and in the rhizosphere of spartina alterniflora. | phylogenetic diversity and community composition of sulfate-reducing bacteria in a salt marsh sediment and in the rhizosphere of spartina alterniflora were investigated. uncultivated desulfobacteriaceae family-related phylotypes were studied by selectively amplifying 16s rrna gene fragments from dna extracted from salt marsh rhizosphere samples. two novel phylotypes were retrieved from rhizosphere samples, with a01 having 89.1% sequence similarity with desulfococcus multivorans and 4d19 having 9 ... | 1997 | 9327553 |
| 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 |
| the dissimilatory sulfite reductase from desulfosarcina variabilis is a desulforubidin containing uncoupled metalated sirohemes and s = 9/2 iron-sulfur clusters. | the active site of escherichia coli nadph-sulfite reductase has previously been modeled as a siroheme with its iron bridged to a nearby iron-sulfur cubane, resulting in antiferromagnetic exchange coupling between all iron atoms. the model has been suggested to hold also for other sulfite reductases and nitrite reductases. we have recently challenged the generality of the model with the finding that the epr of fe/s in dissimilatory sulfite reductase (desulfoviridin) from desulfovibrio vulgaris in ... | 1993 | 8399175 |
| 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 |
| effect of lead, mercury and cadmium on a sulphate-reducing bacterium. | a sulphate-reducing bacterial strain isolated from the south-west coast of india resembling desulfosarcina in its physiology was tested for its behaviour towards hgcl(2), cdso(4) and pb(no(3))(2). the order of toxicity to growth of these metal salts in a lactate-based medium at 50 microg ml(-1) concentrations was cd>pb>hg and to respiration pb>cd>hg. inhibitory concentrations (viz. 100 microg ml(-1) of hgcl(2) and 200 microg ml(-1) of pb(no(3)(2)) had a stimulatory effect when the substrate was ... | 1990 | 15092207 |
| competition and coexistence of sulfate-reducing and methanogenic populations in anaerobic biofilms. | the microbial population structure and function of natural anaerobic communities maintained in laboratory fixed-bed biofilm reactors were tracked before and after a major perturbation, which involved the addition of sulfate to the influent of a reactor that had previously been fed only glucose (methanogenic), while sulfate was withheld from a reactor that had been fed both glucose and sulfate (sulfidogenic). the population structure, determined by using phylogenetically based oligonucleotide pro ... | 1996 | 16535428 |
| intact polar membrane lipids in prokaryotes and sediments deciphered by high-performance liquid chromatography/electrospray ionization multistage mass spectrometry--new biomarkers for biogeochemistry and microbial ecology. | lipids from prokaryotic cell membranes can serve as sources of information on the biogeochemistry and microbial ecology of natural ecosystems. traditionally, apolar derivatives of the intact polar membrane molecules, e.g., fatty acids, have been the major target of lipid-based biogeochemical studies. however, when still intact, i.e., as glycerol esters and ethers with attached polar headgroups, membrane lipids are diagnostic for living prokaryotes, which makes them excellent biomarkers for the s ... | 2004 | 15052572 |
| characterization of the marine propionate-degrading, sulfate-reducing bacterium desulfofaba fastidiosa sp. nov. and reclassification of desulfomusa hansenii as desulfofaba hansenii comb. nov. | a rod-shaped, slightly curved sulfate reducer, designated strain p2(t), was isolated from the sulfate-methane transition zone of a marine sediment. cells were motile by means of a single polar flagellum. the strain reduced sulfate, thiosulfate and sulfite to sulfide and used propionate, lactate and 1-propanol as electron donors. strain p2(t) also grew by fermentation of lactate. propionate was oxidized incompletely to acetate and co(2). the dna g+c content was 48.8 mol%. sequence analysis of the ... | 2004 | 15023950 |
| 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 |
| bacterial diversity and sulfur cycling in a mesophilic sulfide-rich spring. | an artesian sulfide- and sulfur-rich spring in southwestern oklahoma is shown to sustain an extremely rich and diverse microbial community. laboratory incubations and autoradiography studies indicated that active sulfur cycling is occurring in the abundant microbial mats at zodletone spring. anoxygenic phototrophic bacteria oxidize sulfide to sulfate, which is reduced by sulfate-reducing bacterial populations. the microbial community at zodletone spring was analyzed by cloning and sequencing 16s ... | 2003 | 12957951 |
| analysis of the sulfate-reducing bacterial and methanogenic archaeal populations in contrasting antarctic sediments. | the distribution and activity of communities of sulfate-reducing bacteria (srb) and methanogenic archaea in two contrasting antarctic sediments were investigated. methanogenesis dominated in freshwater lake heywood, while sulfate reduction dominated in marine shallow bay. slurry experiments indicated that 90% of the methanogenesis in lake heywood was acetoclastic. this finding was supported by the limited diversity of clones detected in a lake heywood archaeal clone library, in which most clones ... | 2003 | 12788715 |
| microbial reefs in the black sea fueled by anaerobic oxidation of methane. | massive microbial mats covering up to 4-meter-high carbonate buildups prosper at methane seeps in anoxic waters of the northwestern black sea shelf. strong 13c depletions indicate an incorporation of methane carbon into carbonates, bulk biomass, and specific lipids. the mats mainly consist of densely aggregated archaea (phylogenetic anme-1 cluster) and sulfate-reducing bacteria (desulfosarcina/desulfococcus group). if incubated in vitro, these mats perform anaerobic oxidation of methane coupled ... | 2002 | 12169733 |
| multiple archaeal groups mediate methane oxidation in anoxic cold seep sediments. | no microorganism capable of anaerobic growth on methane as the sole carbon source has yet been cultivated. consequently, information about these microbes has been inferred from geochemical and microbiological observations of field samples. stable isotope analysis of lipid biomarkers and rrna gene surveys have implicated specific microbes in the anaerobic oxidation of methane (aom). here we use combined fluorescent in situ hybridization and secondary ion mass spectrometry analyses, to identify an ... | 2002 | 12032340 |
| molecular phylogenetic analyses of reverse-transcribed bacterial rrna obtained from deep-sea cold seep sediments. | a depth profile of naturally occurring bacterial community structures associated with the deep-sea cold seep push-core sediment in the japan trench at a depth of 5343 m were evaluated using molecular phylogenetic analyses of rna reverse transcription-pcr (rt-pcr) amplified 16s crdna fragments. a total of 137 clones of bacterial crdna (complimentary rdna) phylotypes (phylogenetic types) obtained at three different depths (2-4, 8-10 and 14-16 cm) were identified in partial crdna sequencings. crdna ... | 2002 | 12030853 |
| 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 |
| monoalkylether phospholipids in the sulfate-reducing bacteria desulfosarcina variabilis and desulforhabdus amnigenus. | in this study, cellular lipid compositions of two mesophilic sulfate-reducing bacteria were analyzed by high performance liquid chromatography-mass spectrometry (hplc-ms). in desulfosarcina variabilis and desulforhabdus amnigenus, alkylether-containing phospholipids were detected which had previously only been found in significant amounts in deeply branching hyperthermophilic bacteria and archaea. combining information from hplc-ms analysis and chemical degradation experiments, ether lipids were ... | 2001 | 11734887 |
| structure and diversity of gram-negative sulfate-reducing bacteria on rice roots. | specific pcr assays were used to amplify the 16s rrna genes of the desulfobacteriaceae and the desulfovibrionaceae from extracted environmental dna from rice roots. 16s rdna-based community patterns of the desulfobacteriaceae were generated via terminal restriction fragment length polymorphism analysis from rice roots and compared with bulk soil. the molecular fingerprints showed no significant difference between rice roots and bulk soil, but changes during the vegetation period. 16s rdna clone ... | 2001 | 11451522 |
| high overall diversity and dominance of microdiverse relationships in salt marsh sulphate-reducing bacteria. | the biogeochemistry of north atlantic salt marshes is characterized by the interplay between the marsh grass spartina and sulphate-reducing bacteria (srb), which mineralize the diverse carbon substrates provided by the plants. it was hypothesized that srb populations display high diversity within the sediment as a result of the rich spatial and chemical structuring provided by spartina roots. a 2000-member 16s rrna gene library, prepared with delta-proteobacterial srb-selective primers, was anal ... | 2004 | 15186347 |
| membrane lipid patterns typify distinct anaerobic methanotrophic consortia. | the anaerobic oxidation of methane (aom) is one of the major sinks of this substantial greenhouse gas in marine environments. recent investigations have shown that diverse communities of anaerobic archaea and sulfate-reducing bacteria are involved in aom. most of the relevant archaea are assigned to two distinct phylogenetic clusters, anme-1 and anme-2. a suite of specific (13)c-depleted lipids demonstrating the presence of consortia mediating aom in fossil and recent environments has been estab ... | 2004 | 15258285 |
| polyhydroxyalkanoate (pha) accumulation in sulfate-reducing bacteria and identification of a class iii pha synthase (phaec) in desulfococcus multivorans. | seven strains of sulfate-reducing bacteria (srb) were tested for the accumulation of polyhydroxyalkanoates (phas). during growth with benzoate desulfonema magnum accumulated large amounts of poly(3-hydroxybutyrate) [poly(3hb)]. desulfosarcina variabilis (during growth with benzoate), desulfobotulus sapovorans (during growth with caproate), and desulfobacterium autotrophicum (during growth with caproate) accumulated poly(3hb) that accounted for 20 to 43% of cell dry matter. desulfobotulus sapovor ... | 2004 | 15294771 |
| anaerobic oxidation of dimethylsulfide and methanethiol in mangrove sediments is dominated by sulfate-reducing bacteria. | the oxidation of dimethylsulfide and methanethiol by sulfate-reducing bacteria (srb) was investigated in tanzanian mangrove sediments. the rate of dimethylsulfide and methanethiol accumulation in nonamended sediment slurry (control) incubations was very low while in the presence of the inhibitors tungstate and bromoethanesulfonic acid (bes), the accumulation rates ranged from 0.02-0.34 to 0.2-0.4 nmol g fw sediment(-1) h(-1), respectively. degradation rates of methanethiol and dimethylsulfide ad ... | 2009 | 19744237 |
| anaerobic biodegradation of tce in laboratory columns of fractured saprolite. | an experiment was conducted to determine if biodegradation of trichloroethylene (tce) can occur in previously uncontaminated ground water in saturated fractured saprolite (highly weathered material derived from sedimentary rocks). two undisturbed columns (0.23 m diameter by 0.25 m long) of fractured saprolite were collected from approximately 2 m depth at an uncontaminated site on the oak ridge reservation, oak ridge, tennessee. natural, uncontaminated ground water from the site, which was degas ... | 2004 | 15318776 |
| sulfate-reducing bacteria in tubes constructed by the marine infaunal polychaete diopatra cuprea. | marine infaunal burrows and tubes greatly enhance solute transport between sediments and the overlying water column and are sites of elevated microbial activity. biotic and abiotic controls of the compositions and activities of burrow and tube microbial communities are poorly understood. the microbial communities in tubes of the marine infaunal polychaete diopatria cuprea collected from two different sediment habitats were examined. the bacterial communities in the tubes from a sandy sediment di ... | 2004 | 15574900 |
| temperature-dependent differences in community structure of bacteria involved in degradation of petroleum hydrocarbons under sulfate-reducing conditions. | the aim of this study was to characterize the microbial community involved in anaerobic degradation of petroleum hydrocarbon under low- and moderate-temperature conditions. | 2010 | 21059160 |
| diversity and distribution of methanotrophic archaea at cold seeps. | in this study we investigated by using 16s rrna-based methods the distribution and biomass of archaea in samples from (i) sediments above outcropping methane hydrate at hydrate ridge (cascadia margin off oregon) and (ii) massive microbial mats enclosing carbonate reefs (crimea area, black sea). the archaeal diversity was low in both locations; there were only four (hydrate ridge) and five (black sea) different phylogenetic clusters of sequences, most of which belonged to the methanotrophic archa ... | 2005 | 15640223 |
| diversity and vertical distribution of cultured and uncultured deltaproteobacteria in an intertidal mud flat of the wadden sea. | the diversity and distribution of deltaproteobacteria in an intertidal mud flat of the german wadden sea was characterized by molecular biological techniques and cultivation. a 16s rrna gene library generated with general primers (303 clones) suggested that sulfate-reducing bacteria (srb) related to desulfobulbaceae and desulfosarcina were abundant. fluorescence in situ hybridization (fish) with probes targeting these groups was used to characterize their vertical distribution. the combination o ... | 2005 | 15683401 |
| structure of sediment-associated microbial communities along a heavy-metal contamination gradient in the marine environment. | microbial community composition and structure were characterized in marine sediments contaminated for >80 years with cadmium, copper, lead, and zinc. four sampling sites that encompass a wide range of sediment metal loads were compared in a norwegian fjord (sorfjord). hcl-extractable metals and organic matter constantly decreased from the most contaminated site (s1) to the control site (s4). all sampling sites presented low polychlorinated biphenyl (pcb) concentrations (sigma(7)pcb < 7.0 ng g [d ... | 2005 | 15691917 |
| 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 |
| growth and population dynamics of anaerobic methane-oxidizing archaea and sulfate-reducing bacteria in a continuous-flow bioreactor. | the consumption of methane in anoxic marine sediments is a biogeochemical phenomenon mediated by two archaeal groups (anme-1 and anme-2) that exist syntrophically with sulfate-reducing bacteria. these anaerobic methanotrophs have yet to be recovered in pure culture, and key aspects of their ecology and physiology remain poorly understood. to characterize the growth and physiology of these anaerobic methanotrophs and the syntrophic sulfate-reducing bacteria, we incubated marine sediments using an ... | 2005 | 16000782 |
| molecular characterization of sulfate-reducing bacteria in a new england salt marsh. | sulfate reduction, mediated by sulfate-reducing bacteria (srb), is the dominant remineralization pathway in sediments of new england salt marshes. high sulfate reduction rates are associated with the rhizosphere of spartina alterniflora when plants elongate aboveground. the growth process concurrently produces significant amounts of new rhizome material belowground and the plants leak dissolved organic compounds. this study investigated the diversity of srb in a salt marsh over an annual growth ... | 2005 | 16011754 |
| a comparison of stable-isotope probing of dna and phospholipid fatty acids to study prokaryotic functional diversity in sulfate-reducing marine sediment enrichment slurries. | marine sediment slurries enriched for anaerobic, sulfate-reducing prokaryotic communities utilizing glucose and acetate were used to provide the first comparison between stable-isotope probing (sip) of phospholipid fatty acids (plfa) and dna (16s rrna and dsra genes) biomarkers. different 13c-labelled substrates (glucose, acetate and pyruvate) at low concentrations (100 microm) were used over a 7-day incubation to follow and identify carbon flow into different members of the community. limited c ... | 2006 | 16913918 |
| 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 |
| in vitro cell growth of marine archaeal-bacterial consortia during anaerobic oxidation of methane with sulfate. | anoxic sediment from a methane hydrate area (hydrate ridge, north-east pacific; water depth 780 m) was incubated in a long-term laboratory experiment with semi-continuous supply of pressurized [1.4 mpa (14 atm)] methane and sulfate to attempt in vitro propagation of the indigenous consortia of archaea (anme-2) and bacteria (dss, desulfosarcina/desulfococcus cluster) to which anaerobic oxidation of methane (aom) with sulfate has been attributed. during 24 months of incubation, the rate of aom (me ... | 2007 | 17227423 |
| alkane biodegradation and dynamics of phylogenetic subgroups of sulfate-reducing bacteria in an anoxic coastal marine sediment artificially contaminated with oil. | for 503 days, unoiled control and artificially oiled sediments were incubated in situ at 20m water depth in a mediterranean coastal area. degradation of the aliphatic fraction of the oil added was followed by gc-ms. at the same time, terminal restriction fragment length polymorphism (t-rflp) of 16s rrna encoding genes was used to detect dynamics in the sulfate-reducing bacteria (srb) community in response to the oil contamination. specific polymerase chain reaction (pcr) primer sets for five gen ... | 2007 | 17337033 |
| quantifying expression of a dissimilatory (bi)sulfite reductase gene in petroleum-contaminated marine harbor sediments. | the possibility of quantifying in situ levels of transcripts for dissimilatory (bi)sulfite reductase (dsr) genes to track the activity of sulfate-reducing microorganisms in petroleum-contaminated marine harbor sediments was evaluated. phylogenetic analysis of the cdna generated from mrna for a ca. 1.4 kbp portion of the contiguous dsra and dsrb genes suggested that desulfosarcina species, closely related to cultures known to anaerobically oxidize aromatic hydrocarbons, were active sulfate reduce ... | 2008 | 17786505 |
| anaerobic oxidation of short-chain hydrocarbons by marine sulphate-reducing bacteria. | the short-chain hydrocarbons ethane, propane and butane are constituents of natural gas. they are usually assumed to be of thermochemical origin, but biological formation of ethane and propane has been also observed. microbial utilization of short-chain hydrocarbons has been shown in some aerobic species but not in anaerobic species of bacteria. on the other hand, anaerobic utilization of short-chain hydrocarbons would in principle be expected because various anaerobic bacteria grow with higher ... | 2007 | 17882164 |
| molecular analysis of the spatio-temporal distribution of sulfate-reducing bacteria (srb) in camargue (france) hypersaline microbial mat. | the spatio-temporal distribution of sulfate-reducing bacteria (srb) in the microbial mat of camargue (salins-de-giraud, france) was investigated by molecular approaches at both microscale spatial resolution and different taxonomic organization levels. the vertical distribution of the srb populations was correlated with oxygen and sulfide microgradient fluctuations. comparisons of terminal restriction fragment length polymorphism (t-rflp) fingerprints showed distinct locations of some operational ... | 2008 | 17952491 |
| inorganic carbon fixation by sulfate-reducing bacteria in the black sea water column. | the black sea is the largest anoxic water basin on earth and its stratified water column comprises an upper oxic, middle suboxic and a lower permanently anoxic, sulfidic zone. the abundance of sulfate-reducing bacteria (srb) in water samples was determined by quantifying the copy number of the dsra gene coding for the alpha subunit of the dissimilatory (bi)sulfite reductase using real-time polymerase chain reaction. the dsra gene was detected throughout the whole suboxic and anoxic zones. the ma ... | 2007 | 17991030 |
| biogeography of sulfate-reducing prokaryotes in river floodplains. | in this study, a large-scale field survey was conducted to describe the biogeography of sulfate-reducing prokaryotes (srps) in river floodplains. fingerprints obtained with three methods, i.e. 16s rrna gene-based oligonucleotide microarray, dsrb-based denaturing gradient gel electrophoresis (dgge) and polar lipid-derived fatty acid (plfa) analyses, were used as a proxy to describe the srps community diversity. each set of profiles was subjected to a combined multivariate/correlation analysis in ... | 2008 | 18466362 |
| geomicrobial characterization of gas hydrate-bearing sediments along the mid-chilean margin. | bacterial diversity in eight sediment cores from the mid-chilean margin was studied using length heterogeneity (lh)-pcr, and described in relation to in situ geochemical conditions. dna from the sulfate-methane transition (smt) of three cores [one containing methane gas; two proximal to a gas hydrate mound (ghm)] was cloned and sequenced. clones related to uncultured relatives of desulfosarcina variabilis were found in all clone libraries and dominated one. desulfosarcina variabilis related clon ... | 2008 | 18522645 |
| diversity of sulfate-reducing genes (dsrab) in sediments from puget sound. | the aims of this study were to characterize the population structure and diversity of sulfate-reducing bacteria (srb) from three distinct sites at puget sound, and relate the biogeochemical properties of the sediments to the sulfate-reducer communities. the population composition and diversity of sulfate-reducing bacteria carrying dsrab genes from surface puget sound sediments was investigated using a polymerase chain reaction-based cloning approach. sediment cores were collected from three diff ... | 2008 | 18942577 |
| variations in archaeal and bacterial diversity associated with the sulfate-methane transition zone in continental margin sediments (santa barbara basin, california). | the sulfate-methane transition zone (smtz) is a widespread feature of continental margins, representing a diffusion-controlled interface where there is enhanced microbial activity. smtz microbial activity is commonly associated with the anaerobic oxidation of methane (aom), which is carried out by syntrophic associations between sulfate-reducing bacteria and methane-oxidizing archaea. while our understanding of the microorganisms catalyzing aom has advanced, the diversity and ecological role of ... | 2009 | 19139232 |
| ultrastructure, tactic behaviour and potential for sulfate reduction of a novel multicellular magnetotactic prokaryote from north sea sediments. | multicellular magnetotactic prokaryotes (mmps) represent highly organized, spherical and motile aggregates of 10-40 bacterial cells containing magnetosomes. although consisting of different cells, each with its own magnetosomes and flagellation, mmps orient themselves within a magnetic field and exhibit magnetotaxis. so far, mmps have only been found in several north and south american coastal lagoons and salt marshes. in the present study, a novel type of mmp was discovered in coastal tidal san ... | 2009 | 19220395 |
| sulfate-reducing bacteria in marine sediment (aarhus bay, denmark): abundance and diversity related to geochemical zonation. | in order to better understand the main factors that influence the distribution of sulfate-reducing bacteria (srb), their population size and their metabolic activity in high- and low-sulfate zones, we studied the srb diversity in 3- to 5-m-deep sediment cores, which comprised the entire sulfate reduction zone and the upper methanogenic zone. by combining ema (ethidium monoazide that can only enter damaged/dead cells and may also bind to free dna) treatment with real-time pcr, we determined the d ... | 2009 | 19220398 |
| 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 |
| 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 |
| [distribution and diversity of sulfate-reducing bacteria in a crude oil gathering and transferring system]. | the distribution of sulfureted hydrogen (h2s) as well as sulfate-reducing bacteria (srb) distribution and diversity in crude oil and oilfield production water samples from a oil gathering and transferring system in changqing oilfield of china were investigated by methylene blue colorimetric method, the most probable number technique and sequence analysis of the 16s rrna gene, respectively. at the oil gathering and transferring system which from oil well through oil flowstation and then to oil co ... | 2010 | 21072940 |
| 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 |
| evidence for anaerobic oxidation of methane in sediments of a freshwater system (lago di cadagno). | anaerobic oxidation of methane (aom) has been investigated in sediments of a high alpine sulfate-rich lake. hot spots of aom could be identified based on geochemical and isotopic evidence. very high fractionation of methane (α=1.031) during oxidation was observed in the uppermost sediment layers, where methane is oxidized most likely with sulfate-containing bottom waters. however, we could not exclude that other electron acceptors such as iron, or manganese might also be involved. light carbon i ... | 2011 | 21244447 |
| bacterial enzymes for dissimilatory sulfate reduction in a marine microbial mat (black sea) mediating anaerobic oxidation of methane. | anaerobic oxidation of methane (aom) with sulfate is catalysed by microbial consortia of archaea and bacteria affiliating with methanogens and sulfate-reducing deltaproteobacteria respectively. there is evidence that methane oxidation is catalysed by enzymes related to those in methanogenesis, but the enzymes for sulfate reduction coupled to aom have not been examined. we collected microbial mats with high aom activity from a methane seep in the black sea. the mats consisted mainly of archaea of ... | 2011 | 21392199 |
| diversity and biogeochemical structuring of bacterial communities across the porangahau ridge accretionary prism, new zealand. | sediments from the porangahau ridge, located off the northeastern coast of new zealand, were studied to describe bacterial community structure in conjunction with differing biogeochemical regimes across the ridge. low diversity was observed in sediments from an eroded basin seaward of the ridge and the community was dominated by uncultured members of the burkholderiales. chloroflexi/gns and deltaproteobacteria were abundant in sediments from a methane seep located landward of the ridge. gas-char ... | 2011 | 21595727 |
| 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 |
| 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 |
| microbial community structure of sandy intertidal sediments in the north sea, sylt-rømø basin, wadden sea. | molecular biological methods were used to investigate the microbial diversity and community structure in intertidal sandy sediments near the island of sylt (wadden sea) at a site which was characterized for transport and mineralization rates in a parallel study (d. de beer, f. wenzhöfer, t. ferdelman, s.e. boehme, m. huettel, j.e.e. van beusekom, m.e. böttcher, n. musat, n. dubilier, transport and mineralization rates in north sea sandy intertidal sediments, sylt-romo basin, wadden sea, limnol. ... | 2006 | 16431068 |
| enrichment of anme-1 from eckernförde bay sediment on thiosulfate, methane and short-chain fatty acids. | the microorganisms involved in sulfate-dependent anaerobic oxidation of methane (aom) have not yet been isolated. in an attempt to stimulate the growth of anaerobic methanotrophs and associated sulfate reducing bacteria (srb), eckernförde bay sediment was incubated with different combinations of electron donors and acceptors. the organisms involved in aom coupled to sulfate reduction (anme-1, anme-2, and desulfosarcina/desulfococcus) were monitored using specific primers and probes. with thiosul ... | 2011 | 22079869 |
| 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 |