| isolation of a moderate halophilic ammonia-oxidizing bacterium, nitrosococcus mobilis nov. sp. | an ammonia-oxidizing bacterium was isolated from a sample of brackish water (north sea, harbour of husum). it is a motile large coccus 1.5-1.7 mum in diameter. the extensive cytomembrane system occurring as flattened vesicles in the peripheral region of the cytoplasm and as intrusions into the center of the cytoplasm is to be emphasized as a characteristic mark of identification. the lithoautotrophically growing bacterium turned out to be an obligate halophile. because of its physiological and m ... | 1976 | 5979 |
| in situ morphology of nitrifying-like bacteria in aquaculture systems. | the in situ microbiota from several aquaculture facilities with active nitrification was examined by transmission electron microscopy of thin sections for the presence of bacteria that contained intracytoplasmic membranes characteristic of the nitrifying bacteria. colonies of bacteria with the cellular morphology of a species of nitrosomonas were found to be present in both the culture water and in the biological filter slime of a freshwater chinook salmon (oncorhynchus tshawytscha) culture syst ... | 1976 | 938036 |
| the small-scale production of [u-14c]acetylene from ba14co3: application to labeling of ammonia monooxygenase in autotrophic nitrifying bacteria. | a small-scale method has been adapted from an established procedure for the generation of [u-14c]acetylene from inexpensive and commonly available precursors. the method involves the fusing of ba14co3 with excess barium metal to produce ba14c2. the bac2 is reacted with water to generate acetylene which is then selectively dissolved into dimethyl sulfoxide (dmso). the results presented demonstrate the effect of ba:baco3 ratio on the concentrations of various gases released during the hydrolysis r ... | 1990 | 2291478 |
| physiology, biochemistry, and specific inhibitors of ch4, nh4+, and co oxidation by methanotrophs and nitrifiers. | ammonia oxidizers (family nitrobacteraceae) and methanotrophs (family methylococcaceae) oxidize co and ch4 to co2 and nh4+ to no2-. however, the relative contributions of the two groups of organisms to the metabolism of co, ch4, and nh4+ in various environments are not known. in the ammonia oxidizers, ammonia monooxygenase, the enzyme responsible for the conversion of nh4+ to nh2oh, also catalyzes the oxidation of ch4 to ch3oh. ammonia monooxygenase also mediates the transformation of ch3oh to c ... | 1989 | 2496288 |
| deoxyribonucleic acid homologies among 96 strains of ammonia-oxidizing bacteria. | dna of 96 strains of the genera nitrosomonas, nitrosococcus, nitrosospira, nitrosolobus, and nitrosovibrio was isolated and analysed spectrophotometrically. percentages of guanine plus cytosine (g + c) content, genome sizes, and dna-dna homologies were determined. the results indicated the presence of eight nitrosomonas species, three or four nitrosococcus species, five nitrosospira species, and two species of both nitrosolobus and nitrosovibrio. dna homologies between strains of a separate spec ... | 1985 | 4004447 |
| incorporation of organic compounds into cell protein by lithotrophic, ammonia-oxidizing bacteria. | incorporation of organic compounds into cell protein by the obligate chemolithotrophs nitrosomonas spec., nitrosococcus oceanus, nitrosococcus mobilis, nitrosovibrio tenuis, nitrosolobus spec., and nitrosospira spec. was studied. in the presence of ammonia as energy source organic substrates were supplied. distribution of 14c into cell amino acids arising from 14c-labelled glucose, na-pyruvate, and na-acetate was investigated. while carbon from glucose was distributed unrestricted, carbon from p ... | 1982 | 7149699 |
| serological studies on lithotrophic, ammonia oxidizing bacteria. | rabbit antisera were prepared against living cells of six different ammonia oxidizing nitrifying bacteria. they were examined as to cross-reactivity in the agglutination test (microtiter-system) with 24 nitrifier strains, including members of all known genera. usually distinct cross-reactions were obtained only within the genera, but some exceptions were noticed. there was stated a clear cross-reaction between the two anti-nitrosospira-antisera and the four tested nitrosolobus strains. in some c ... | 1980 | 7212926 |
| evidence that particulate methane monooxygenase and ammonia monooxygenase may be evolutionarily related. | genes encoding particulate methane monooxygenase and ammonia monooxygenase share high sequence identity. degenerate oligonucleotide primers were designed, based on regions of shared amino acid sequence between the 27-kda polypeptides, which are believed to contain the active sites, of particulate methane monooxygenase and ammonia monooxygenase. a 525-bp internal dna fragment of the genes encoding these polypeptides (pmoa and amoa) from a variety of methanotrophic and nitrifying bacteria was ampl ... | 1995 | 7590173 |
| amplification of the amoa gene from diverse species of ammonium-oxidizing bacteria and from an indigenous bacterial population from seawater. | because the chemolithotrophic ammonium-oxidizing bacteria are an integral component of nitrogen biogeochemistry, a sensitive and accurate method to detect this ecologically important group of microorganisms is needed. the amoa gene of these organisms encodes the active site of ammonia monooxygenase, an enzyme unique to this group of nitrifying bacteria. we report here the use of the pcr technique to detect the amoa gene from pure cultures of chemolithotrophic ammonium-oxidizing bacteria, ammoniu ... | 1995 | 7618882 |
| the phylogeny of autotrophic ammonia-oxidizing bacteria as determined by analysis of 16s ribosomal rna gene sequences. | partial sequences of the 16s ribosomal rna genes of eleven autotrophic ammonia-oxidizing bacteria were determined by pcr amplification from small amounts of heat-lysed biomass followed by direct sequencing of pcr products. the sequences were aligned with those of representative proteobacteria and phylogenetic trees inferred using both parsimony and distance matrix methods. this confirmed that the autotrophic ammonia-oxidizers comprise two major lines of descent within the proteobacteria. nitroso ... | 1993 | 7689633 |
| evolutionary relationships among ammonia- and nitrite-oxidizing bacteria. | comparative 16s rrna sequencing was used to evaluate phylogenetic relationships among selected strains of ammonia- and nitrite-oxidizing bacteria. all characterized strains were shown to be affiliated with the proteobacteria. the study extended recent 16s rrna-based studies of phylogenetic diversity among nitrifiers by the comparison of eight strains of the genus nitrobacter and representatives of the genera nitrospira and nitrospina. the later genera were shown to be affiliated with the delta s ... | 1994 | 7961414 |
| detection of nitrosococcus oceanus in a mediterranean lagoon by immunofluorescence. | the autotrophic ammonium-oxidizing bacterium nitrosococcus oceanus was studied in the brackish lake of ganzirri by cultural and immunofluorescent methods. the preparation of the specific antiserum in rabbits is reported. the polyclonal antiserum for nitrosococcus oceanus cross-reacted with other ammonia oxidizing strains, but not with other marine bacteria. temporal changes were determined by taking monthly water samples from a station 6 m deep and the distribution in sediments was investigated ... | 1996 | 8698662 |
| combined molecular and conventional analyses of nitrifying bacterium diversity in activated sludge: nitrosococcus mobilis and nitrospira-like bacteria as dominant populations. | the ammonia-oxidizing and nitrite-oxidizing bacterial populations occurring in the nitrifying activated sludge of an industrial wastewater treatment plant receiving sewage with high ammonia concentrations were studied by use of a polyphasic approach. in situ hybridization with a set of hierarchical 16s rrna-targeted probes for ammonia-oxidizing bacteria revealed the dominance of nitrosococcus mobilis-like bacteria. the phylogenetic affiliation suggested by fluorescent in situ hybridization (fish ... | 1998 | 9687471 |
| assessment of changes in microbial community structure during operation of an ammonia biofilter with molecular tools. | biofiltration has been used for two decades to remove odors and various volatile organic and inorganic compounds in contaminated off-gas streams. although biofiltration is widely practiced, there have been few studies of the bacteria responsible for the removal of air contaminants in biofilters. in this study, molecular techniques were used to identify bacteria in a laboratory-scale ammonia biofilter. both 16s rrna and ammonia monooxygenase (amoa) genes were used to characterize the heterotrophi ... | 1998 | 9835577 |
| taxon-specific content of oligonucleotide triplets in 16s rrnas of anoxygenic phototrophic and nitrifying bacteria. | theoretical evaluation of the content of oligonucleotide triplets aaa, ccc, and uau in 16s rrnas of anoxygenic phototrophic bacteria (genera chlorobium; chloroflexus; chromatium: rhodopseudomonas) and nitrifying bacteria (genera nitrosococcus, nitrosomonas, nitrosolobus, nitrosovibrio, nitrospira, nitrospina, nitrobacter) showed that the number of the aaa, ccc or uau triplets in 16s rrnas specifically corresponds to the genus and species of bacteria. the ratio of aaa and ccc triplet numbers in t ... | 1999 | 10049622 |
| the amo operon in marine, ammonia-oxidizing gamma-proteobacteria. | while there is an extensive database of genes encoding ammonia monooxygenase (amo) found in the ammonia-oxidizing beta-proteobacteria, few amo sequences are available representing the gamma-proteobacteria. we sequenced the complete amo operon (amocab) for nitrosococcus oceani (atcc 19707), a marine, autotrophic, ammonia-oxidizing bacterium belonging to the gamma-subdivision of the proteobacteria. an additional autotrophic, ammonia-oxidizing bacterium isolated from a marine environment (strain c- ... | 1999 | 10547440 |
| analysis of ammonia-oxidizing bacteria from hypersaline mono lake, california, on the basis of 16s rrna sequences. | ammonia-oxidizing bacteria were detected by pcr amplification of dna extracted from filtered water samples throughout the water column of mono lake, california. ammonia-oxidizing members of the beta subdivision of the division proteobacteria (beta-subdivision proteobacteria) were detected using previously characterized pcr primers; target sequences were detected by direct amplification in both surface water and below the chemocline. denaturing gradient gel electrophoresis analysis indicated the ... | 2000 | 10877781 |
| pacific northwest marine sediments contain ammonia-oxidizing bacteria in the beta subdivision of the proteobacteria. | the diversity of ammonia-oxidizing bacteria in aquatic sediments was studied by retrieving ammonia monooxygenase and methane monooxygenase gene sequences. methanotrophs dominated freshwater sediments, while beta-proteobacterial ammonia oxidizers dominated marine sediments. these results suggest that gamma-proteobacteria such as nitrosococcus oceani are minor members of marine sediment ammonia-oxidizing communities. | 2000 | 11010911 |
| phylogeny of all recognized species of ammonia oxidizers based on comparative 16s rrna and amoa sequence analysis: implications for molecular diversity surveys. | the current perception of evolutionary relationships and the natural diversity of ammonia-oxidizing bacteria (aob) is mainly based on comparative sequence analyses of their genes encoding the 16s rrna and the active site polypeptide of the ammonia monooxygenase (amoa). however, only partial 16s rrna sequences are available for many aob species and most aob have not yet been analyzed on the amoa level. in this study, the 16s rdna sequence data of 10 nitrosomonas species and nitrosococcus mobilis ... | 2000 | 11097916 |
| polyclonal antibodies recognizing the amob protein of ammonia oxidizers of the beta-subclass of the class proteobacteria. | a 41-kda protein of nitrosomonas eutropha was purified, and the n-terminal amino acid sequence was found to be nearly identical with the sequence of amob, a subunit of ammonia monooxygenase. this protein was used to develop polyclonal antibodies, which were highly specific for the detection of the four genera of ammonia oxidizers of the beta-subclass of proteobacteria (nitrosomonas, including nitrosococcus mobilis, which belongs phylogenetically to nitrosomonas; nitrosospira; nitrosolobus; and n ... | 2001 | 11133435 |
| differential inhibition in vivo of ammonia monooxygenase, soluble methane monooxygenase and membrane-associated methane monoxygenase by phenylacetylene. | phenylacetylene was investigated as a differential inhibitor of ammonia monooxygenase (amo), soluble methane monooxygenase (smmo) and membrane-associated or particulate methane monooxygenase (pmmo) in vivo. at phenylacetylene concentrations > 1 microm, whole-cell amo activity in nitrosomonas europaea was completely inhibited. phenylacetylene concentrations above 100 microm inhibited more than 90% of smmo activity in methylococcus capsulatus bath and methylosinus trichosporium ob3b. in contrast, ... | 2000 | 11233157 |
| recommended conservation of the names streptococcus sanguis, streptococcus rattus, streptococcus cricetus, and seven other names included in the approved lists of bacterial names. request for an opinion. | with reference to the first principle of the international code of nomenclature of bacteria, which emphasizes stability of names, it is proposed that the original names streptococcus sanguis, streptococcus rattus, streptococcus cricetus, erwinia ananas, eubacterium tarantellus, lactobacillus sake, nitrosococcus oceanus, pseudomonas betle, rickettsia canada and streptomyces rangoon, all included in the approved lists of bacterial names, be conserved. request for an opinion. | 2001 | 11321121 |
| identification of bacteria responsible for ammonia oxidation in freshwater aquaria. | culture enrichments and culture-independent molecular methods were employed to identify and confirm the presence of novel ammonia-oxidizing bacteria (aob) in nitrifying freshwater aquaria. reactors were seeded with biomass from freshwater nitrifying systems and enriched for aob under various conditions of ammonia concentration. surveys of cloned rrna genes from the enrichments revealed four major strains of aob which were phylogenetically related to the nitrosomonas marina cluster, the nitrososp ... | 2001 | 11722936 |
| phylogeny and functional expression of ribulose 1,5-bisphosphate carboxylase/oxygenase from the autotrophic ammonia-oxidizing bacterium nitrosospira sp. isolate 40ki. | the autotrophic ammonia-oxidizing bacteria (aob), which play an important role in the global nitrogen cycle, assimilate co(2) by using ribulose 1,5-bisphosphate carboxylase/oxygenase (rubisco). here we describe the first detailed study of rubisco (cbb) genes and proteins from the aob. the cbbls genes from nitrosospira sp. isolate 40ki were cloned and sequenced. partial sequences of the rubisco large subunit (cbbl) from 13 other aob belonging to the beta and gamma subgroups of the class proteobac ... | 2002 | 11751824 |
| detailed phylogeny of ammonia-oxidizing bacteria determined by rdna sequences and dna homology values. | a comparison of the phylogeny of 38 isolates of chemolithoautotrophic ammonia-oxidizing bacteria (aob) based on 16s rrna gene sequences, 16s-235 rdna intergenic spacer region (isr) sequences and species affiliations based on dna homology values was performed. the organisms studied all belong to the beta-subclass of the proteobacteria and included representatives of nitrosomonas, nitrosococcus and nitrosospira. the similarity values of the 16s rdna sequences were high, particularly within the nit ... | 2001 | 11760943 |
| diversity of ammonia monooxygenase operon in autotrophic ammonia-oxidizing bacteria. | autotrophic ammonia-oxidizing bacteria use the essential enzyme ammonia monooxygenase (amo) to transform ammonia to hydroxylamine. the amo operon consists of at least three genes, amoc, amoa, and amob; amoa encodes the subunit containing the putative enzyme active site. the use of the amo genes as functional markers for ammonia-oxidizing bacteria in environmental applications requires knowledge of the diversity of the amo operon on several levels: (1) the copy number of the operon in the genome, ... | 2002 | 11807563 |
| determination of the bacterial processes which are sources of nitrous oxide production in marine samples. | partial denitrification and the initial step of nitrification are the main biological processes which produce nitrous oxide. in order to determine the contribution that these processes have in nitrous oxide production, the efficiency of different inhibitors on nitrifying activity has been tested, and the effect on denitrifying activity has been investigated, using culture strains and natural marine samples. a good nitrification inhibitor should not affect denitrification. a low partial pressure ... | 2002 | 11827333 |
| worldwide distribution of nitrosococcus oceani, a marine ammonia-oxidizing gamma-proteobacterium, detected by pcr and sequencing of 16s rrna and amoa genes. | diversity of cultured ammonia-oxidizing bacteria in the gamma-subdivision of the proteobacteria was investigated by using strains isolated from various parts of the world ocean. all the strains were very similar to each other on the basis of the sequences of both the 16s rrna and ammonia monooxygenase genes and could be characterized as a single species. sequences were also cloned directly from environmental dna from coastal pacific and atlantic sites, and these sequences represented the first n ... | 2002 | 12147525 |
| production of gaseous nitrogen compounds in a novel process for ammonium removal. | the production of gaseous nitrogen compounds, particularly the greenhouse gas nitrous oxide, was investigated in a novel process for ammonium removal from wastewater. the process is based on the adsorption of ammonium on zeolite followed by bioregeneration. the zeolite serves the dual purpose of an ion exchanger and a physical carrier for nitrifying bacteria which bio-regenerate the ammonium saturated mineral. an analysis of the nitrifying population composition in the reactor fed with simulated ... | 2002 | 12216627 |
| susceptibility of ammonia-oxidizing bacteria to nitrification inhibitors. | activity of nitrification inhibitors to several typical ammonia-oxidizing bacteria isolated recently, i. e. nitrosococcus, nitrosolobus, nitrosomonas, nitrosospira and nitrosovibrio species was assayed using 2-amino-4-methyl-trichloromethyl-1,3,5-triazine (mast), 2-amino-4-tribromomethyl-6-trichloromethyl-1,3,5-triazine (br-mast), 2-chloro-6-trichloromethylpyridine (nitrapyrin) and others, and compared to confirm the adequate control of ammonia-oxidizing bacteria by the inhibitors. the order of ... | 2003 | 12710742 |
| structure and activity of multiple nitrifying bacterial populations co-existing in a biofilm. | a biofilm from a nitrifying pilot-scale sequencing batch reactor was investigated for effects of varying process conditions on its microscale activity and structure. microsensor measurements of oxygen, substrates and products of nitrification were applied under incubation at different ammonium and oxygen concentrations which reflected various situations during a treatment cycle. a high net n loss was observed under high ammonium (ha) concentrations in contrast to low ones. additionally, results ... | 2003 | 12713462 |
| re-isolation of the nitrosococcus of winogradsky. | | 1963 | 14048725 |
| dynamic response of nitrifying activated sludge batch culture to increased chloride concentration. | dynamic response of nitrifying activated sludge batch cultures to increased chloride concentration was studied in this paper, which focused upon the changes in the specific nitrification rate (snr) and nitrifier population when the chloride level was gradually or stepwise increased to 30,000 mg cl l-1. the dominant species of ammonia-oxidizers and nitriteoxidizers in the population were examined by fluorescent in situ hybridization technique with 16s rrna-targeted oligonucleotide probes. it was ... | 2003 | 14509699 |
| a comparitive study of ammonia-oxidizing bacteria in lab-scale industrial wastewater treatment reactors. | the diversity and community structure of the beta-proteobacterial ammonia oxidising bacteria (aob) in a range of different lab-scale industrial wastewater treatment reactors were compared. three of the reactors treat waste from mixed domestic and industrial sources whereas the other reactor treats waste solely of industrial origin. pcr with aob selective primers was combined with denaturing gradient ge electrophoresis to allow comparative analysis of the dominant aob populations and the phylogen ... | 2003 | 14518850 |
| molecular analysis of microbial communities in nitrification and denitrification reactors treating high ammonia leachate. | molecular analysis of microbial populations in two bench-scale nitrification and denitrification reactors fed with high ammonia landfill leachate was conducted in this study by using dgge, cloning, and fish techniques in addition to classical efficiency control parameters. nitrification tank was operated with a computer-controlled alkalinity dosing system to supply the alkalinity intermittently as consumed on the basis of on-line ph monitoring. by keeping the ph at 7.0 with this system, 99% nitr ... | 2003 | 14524656 |
| use of amob as a new molecular marker for ammonia-oxidizing bacteria. | specific molecular determination and classification of ammonia-oxidizing bacteria have relied on the use of conventional markers such as 16s rdna. however, this gene does not satisfactorily provide a wide vision of all phylogenetic lineages. despite the initial expectations, the use of functional genes as for example amoa has only been useful to corroborate the established taxonomy. ammonia-oxidizing bacteria constitute a physiological group that crosses over principal phylogenetic radiations. t ... | 2004 | 15003690 |
| urease-encoding genes in ammonia-oxidizing bacteria. | many but not all ammonia-oxidizing bacteria (aob) produce urease (urea amidohydrolase, ec 3.5.1.5) and are capable of using urea for chemolithotrophic growth. we sequenced the urease operons from two aob, the beta-proteobacterium nitrosospira sp. strain npav and the gamma-proteobacterium nitrosococcus oceani. in both organisms, all seven urease genes were contiguous: the three structural urease genes ureabc were preceded and succeeded by the accessory genes ured and ureefg, respectively. green f ... | 2004 | 15066830 |
| denaturing gradient gel electrophoretic analysis of ammonia-oxidizing bacterial community structure in the lower seine river: impact of paris wastewater effluents. | the seine river is strongly affected by the effluents from the acheres wastewater treatment plant (wwtp) downstream of the city of paris. we have shown that the effluents introduce large amounts of ammonia and inoculate the receiving medium with nitrifying bacteria. the aim of the present study was to investigate the diversity of the ammonia-oxidizing bacterial population by identifying autochthonous bacteria from upstream and/or allochthonous ammonia-oxidizing bacteria from the wwtp effluents. ... | 2004 | 15528539 |
| structure and sequence conservation of hao cluster genes of autotrophic ammonia-oxidizing bacteria: evidence for their evolutionary history. | comparison of the organization and sequence of the hao (hydroxylamine oxidoreductase) gene clusters from the gammaproteobacterial autotrophic ammonia-oxidizing bacterium (aaob) nitrosococcus oceani and the betaproteobacterial aaob nitrosospira multiformis and nitrosomonas europaea revealed a highly conserved gene cluster encoding the following proteins: hao, hydroxylamine oxidoreductase; orf2, a putative protein; cyca, cytochrome c(554); and cycb, cytochrome c(m)(552). the deduced protein sequen ... | 2005 | 16151127 |
| phylogenetic analysis of nitric oxide reductase gene homologues from aerobic ammonia-oxidizing bacteria. | nitric oxide (no) and nitrous oxide (n2o) are climatically important trace gases that are produced by both nitrifying and denitrifying bacteria. in the denitrification pathway, n2o is produced from nitric oxide (no) by the enzyme nitric oxide reductase (nor). the ammonia-oxidizing bacterium nitrosomonas europaea also possesses a functional nitric oxide reductase, which was shown recently to serve a unique function. in this study, sequences homologous to the large subunit of nitric oxide reductas ... | 2004 | 16329906 |
| communities of ammonia-oxidizing bacteria in activated sludge of various sewage treatment plants in tokyo. | we investigated ammonia-oxidizing bacteria in activated sludge collected from 12 sewage treatment systems, whose ammonia removal and treatment processes differed, during three different seasons. we used real-time pcr quantification to reveal total bacterial numbers and total ammonia oxidizer numbers, and used specific pcr followed by denaturing gel gradient electrophoresis, cloning, and sequencing of 16s rrna genes to analyze ammonia-oxidizing bacterial communities. total bacterial numbers and t ... | 2005 | 16332320 |
| high levels of nitrifying bacteria in intermittently aerated reactors treating high ammonia wastewater. | changes in the fractions of ammonia-oxidizing bacteria and nitrite-oxidizing bacteria in two laboratory-scale reactors were investigated using 16s rrna probe hybridizations. the reactors were operated in intermittent aeration mode and different aeration cycles to treat anaerobically digested swine wastewater with ammonia concentrations up to 175 mg nh(3)-n/l. high ammonia removals (>98.8%) were achieved even with increased nitrogen loads and lower aeration: non-aeration time ratios of 1h:3h. nit ... | 2005 | 16332337 |
| effects of aeration cycles on nitrifying bacterial populations and nitrogen removal in intermittently aerated reactors. | the effects of the lengths of aeration and nonaeration periods on nitrogen removal and the nitrifying bacterial community structure were assessed in intermittently aerated (ia) reactors treating digested swine wastewater. five ia reactors were operated in parallel with different aeration-to-nonaeration time ratios (ana). populations of ammonia-oxidizing bacteria (aob) and nitrite-oxidizing bacteria (nob) were monitored using 16s rrna slot blot hybridizations. aob species diversity was assessed u ... | 2005 | 16332848 |
| immunofluorescent assay for the marine ammonium-oxidizing bacterium nitrosococcus oceanus. | nitrification is one of the important microbiological transformations of nitrogen in the ocean. traditional enrichment-culture methods for enumerating the autotrophic bacteria which oxidize ammonium to nitrite are very time consuming (months) and are believed to seriously underestimate natural abundances. a fluorescent-antibody assay for a marine ammonium-oxidizing bacterium was developed to provide a rapid and direct means of identifying these microorganisms. antibodies to nitrosococcus oceanus ... | 1980 | 16345557 |
| production of no(2) and n(2)o by nitrifying bacteria at reduced concentrations of oxygen. | pure cultures of the marine ammonium-oxidizing bacterium nitrosomonas sp. were grown in the laboratory at oxygen partial pressures between 0.005 and 0.2 atm (0.18 to 7 mg/liter). low oxygen conditions induced a marked decrease in the rate for production of no(2), from 3.6 x 10 to 0.5 x 10 mmol of no(2) per cell per day. in contrast, evolution of n(2)o increased from 1 x 10 to 4.3 x 10 mmol of n per cell per day. the yield of n(2)o relative to no(2) increased from 0.3% to nearly 10% (moles of n i ... | 1980 | 16345632 |
| assimilatory sulfur metabolism in marine microorganisms: considerations for the application of sulfate incorporation into protein as a measurement of natural population protein synthesis. | the sulfur content of residue protein was determined for pure cultures of nitrosococcus oceanus, desulfovibrio salexigens, 4 mixed populations of fermentative bacteria, 22 samples from mixed natural population enrichments, and 11 nutritionally and morphologically distinct isolates from enrichments of sargasso sea water. the average 1.09 +/- 0.14% (by weight) s in protein for 13 pure cultures agrees with the 1.1% calculated from average protein composition. an operational value encompassing all m ... | 1982 | 16345919 |
| methane oxidation by nitrosococcus oceanus and nitrosomonas europaea. | chemolithotrophic ammonium-oxidizing and nitrite-oxidizing bacteria including nitrosomonas europaea, nitrosococcus oceanus, nitrobacter sp., nitiospina gracilis, and nitrococcus mobilis were examined as to their ability to oxidize methane in the absence of ammonium or nitrite. all ammonium oxidizers tested had the ability to oxidize significant amounts of methane to co(2) and incorporate various amounts into cellular components. none of the nitrite-oxidizing bacteria were capable of methane oxid ... | 1983 | 16346190 |
| biodegradation of halogenated hydrocarbon fumigants by nitrifying bacteria. | three species of nitrifying bacteria were tested for the ability to degrade the halocarbon fumigants methyl bromide, 1,2-dichloropropane, and 1,2-dibromo-3-chloropropane. the soil nitrifiers nitrosomonas europaea and nitrosolobus multiformis degraded all three fumigants, while the marine nitrifier nitrosococcus oceanus degraded only methyl bromide under the conditions tested. inhibition of biodegradation by allylthiourea and acetylene, specific inhibitors of ammonia monooxygenase, suggests that ... | 1990 | 16348264 |
| inhibition of ammonia oxidation in nitrosomonas europaea by sulfur compounds: thioethers are oxidized to sulfoxides by ammonia monooxygenase. | organic sulfur compounds are well-known nitrification inhibitors. the inhibitory effects of dimethylsulfide, dimethyldisulfide, and ethanethiol on ammonia oxidation by nitrosomonas europaea were examined. both dimethylsulfide and dimethyldisulfide were weak inhibitors of ammonia oxidation and exhibited inhibitory characteristics typical of substrates for ammonia monooxygenase (amo). depletion of dimethylsulfide required o(2) and was prevented with either acetylene or allylthiourea, two inhibitor ... | 1993 | 16349086 |
| immunocytochemical localization of membrane-bound ammonia monooxygenase in cells of ammonia oxidizing bacteria. | the intracellular location of the membrane-bound ammonia monooxygenase (amo) in all genera of ammonia oxidizing bacteria (nitrosomonas, nitrosococcus and nitrosospira) was determined by electron microscopic immunocytochemistry. polyclonal antibodies recognizing the two subunits, amoa- and amob-proteins, were used for post-embedding labeling. ultrathin sections revealed that the amob-protein was located in all genera on the cytoplasmic membrane. in cells of nitrosomonas and nitrosococus additiona ... | 2006 | 16395553 |
| development and application of real-time pcr for quantification of specific ammonia-oxidizing bacteria in activated sludge of sewage treatment systems. | in this study, four real-time polymerase chain reaction (pcr) primer sets were developed for the 16s rrna genes of specific ammonia-oxidizing bacteria (aob) found in activated sludge of sewage treatment systems. the primer sets target two of several sequence types of the nitrosomonas oligotropha cluster, members within the nitrosomonas communis cluster, and all members of the nitrosomonas europaea-nitrosococcus mobilis cluster. the detection limit of each primer set was in the range of 3x10(1)-6 ... | 2006 | 16523283 |
| quantification of ammonia-oxidizing bacteria populations in full-scale sewage activated sludge systems and assessment of system variables affecting their performance. | this study carried out quantification of ammonia-oxidizing bacteria (aob) populations in 12 full-scale sewage activated sludge systems that were different in ammonia removals and treatment processes during three different seasons. experiment was divided into 3 parts: 1) analysis of aob communities by pcr-dgge-cloning-sequencing of 16s rrna genes; 2) development of four real-time pcr primer sets for quantification of the particular aob of interest; and 3) quantification of aob populations by usin ... | 2006 | 16898141 |
| post-treatment of a slaughterhouse wastewater: stability of the microbial community of a sequencing batch reactor operated under oxygen limited conditions. | slaughterhouse wastewater is a complex effluent with an important content of organic nitrogen. after an anaerobic treatment where most of the organic matter is removed, the nitrogen, remains as ammonium and post-treatment of the effluent is necessary. sequencing batch reactor (sbr) technology has been developed to completely remove nitrogen in one single reactor combining aerobic and anoxic stages. under oxygen limited conditions only nitrite is produced with concomitant energy saving. the stabi ... | 2006 | 16939105 |
| complete genome sequence of the marine, chemolithoautotrophic, ammonia-oxidizing bacterium nitrosococcus oceani atcc 19707. | the gammaproteobacterium nitrosococcus oceani (atcc 19707) is a gram-negative obligate chemolithoautotroph capable of extracting energy and reducing power from the oxidation of ammonia to nitrite. sequencing and annotation of the genome revealed a single circular chromosome (3,481,691 bp; g+c content of 50.4%) and a plasmid (40,420 bp) that contain 3,052 and 41 candidate protein-encoding genes, respectively. the genes encoding proteins necessary for the function of known modes of lithotrophy and ... | 2006 | 16957257 |
| in situ activity and spatial organization of anaerobic ammonium-oxidizing (anammox) bacteria in biofilms. | we investigated autotrophic anaerobic ammonium-oxidizing (anammox) biofilms for their spatial organization, community composition, and in situ activities by using molecular biological techniques combined with microelectrodes. results of phylogenetic analysis and fluorescence in situ hybridization (fish) revealed that "brocadia"-like anammox bacteria that hybridized with the amx820 probe dominated, with 60 to 92% of total bacteria in the upper part (<1,000 microm) of the biofilm, where high anamm ... | 2007 | 17526785 |
| diversity of ammonia oxidising bacteria in a vertical flow constructed wetland. | vertical flow constructed wetlands (vfcws) with intermittent loading are very suitable for nitrification. ammonia oxidising bacteria (aob) are the limiting step of nitration. therefore the aob community of a full-scale vfcw, receiving municipal wastewater, was investigated within this study. the diversity of the functional gene encoding the alpha-subunit of the ammonia monooxygenase (amoa), present only in aob, was assessed by denaturing gradient gel electrophoresis (dgge). only very few amoa se ... | 2007 | 17802861 |
| zinc chloride inhibition of nitrosococcus mobilis. | nitrosococcus mobilis, a halophilic nitrifier, plays an important role in global nitrogen cycling and in the removal of nitrogen from wastewater treatment plants. however, ammonia oxidation is sensitive to a wide variety of inhibitors, including the heavy metal, zinc. using a metabolic-steady-state reactor, shotgun dna microarrays, and quantitative polymerase chain reaction (qpcr), this research looked at the dynamic physiological and transcriptional responses of n. mobilis to 1 and 10 microm zn ... | 2008 | 17929325 |
| characterization of two new genes, amor and amod, in the amo operon of the marine ammonia oxidizer nitrosococcus oceani atcc 19707. | molecular analysis of the amo gene cluster in nitrosococcus oceani revealed that it consists of five genes, instead of the three known genes, amocab. the two additional genes, orf1 and orf5, were introduced as amor and amod, respectively. putative functions of the amor and amod proteins are discussed. | 2008 | 17993553 |
| primer and probe sets for group-specific quantification of the genera nitrosomonas and nitrosospira using real-time pcr. | use of quantitative real-time pcr (qpcr) with taqman probes is increasingly popular in various environmental works to detect and quantify a specific microorganism or a group of target microorganism. although many aspects of conducting a qpcr assay have become very easy to perform, a proper design of oligonucleotide sequences comprising primers and a probe is still considered as one of the most important aspects of a qpcr application. this work was conducted to design group specific primer and pr ... | 2008 | 18023051 |
| nitrifying community analysis in a single submerged attached-growth bioreactor for treatment of high-ammonia waste stream. | this study investigated the nitrifying community structure in a single-stage submerged attached-growth bioreactor (sagb) that successfully achieved stable nitrogen removal over nitrite of a high-strength ammonia wastewater. the reactor was operated with intermittent aeration and external carbon addition (methanol). with influent ammonia and total kjeldahl nitrogen ranging from 537 to 968 mg/l and 643 to 1510 mg/l, respectively, 85% nitrogen removal was obtained, and effluent was dominated by nit ... | 2007 | 18198696 |
| physiological and phylogenetic study of an ammonium-oxidizing culture at high nitrite concentrations. | oxidation of high-strength ammonium wastewater can lead to exceptionally high nitrite concentrations; therefore, the effect of high nitrite concentration (> 400 mm) was studied using an ammonium-oxidizing enrichment culture in a batch reactor. ammonium was fed to the reactor in portions of 40-150 mm until ammonium oxidation rates decreased and finally stopped. activity was restored by replacing half of the medium, while biomass was retained by a membrane. the ammonium-oxidizing population obtain ... | 2008 | 18289820 |
| molecular analysis of enrichment cultures of ammonia oxidizers from the salar de huasco, a high altitude saline wetland in northern chile. | we analyzed enrichment cultures of ammonia-oxidizing bacteria (aob) collected from different areas of salar de huasco, a high altitude, saline, ph-neutral water body in the chilean altiplano. samples were inoculated into mineral media with 10 mm nh4+ at five different salt concentrations (10, 200, 400, 800 and 1,400 mm nacl). low diversity (up to three phylotypes per enrichment) of beta-aob was detected using 16s rdna and amoa clone libraries. growth of beta-aob was only recorded in a few enrich ... | 2008 | 18305895 |
| monitoring of population shifts in an enriched nitrifying system under gradually increased cadmium loading. | the changes in nitrifying bacterial population under cadmium loading were monitored and evaluated in a laboratory scale continuous-flow enriched nitrification system. for this purpose, the following molecular microbiological methods were used: slot-blot hybridization, denaturing gradient gel electrophoresis (dgge), real-time pcr followed by melting curve analysis, cloning and sequence analysis. the initial cadmium concentration was incrementally increased from 1 to 10mg/l which led to a drop in ... | 2008 | 18462880 |
| diversity of ammonium-oxidizing bacteria in a granular sludge anaerobic ammonium-oxidizing (anammox) reactor. | the ammonium-oxidizing microbial community was investigated in a granular sludge anaerobic ammonium-oxidizing (anammox) reactor that was operated for about 1 year with high anaerobic ammonium oxidation activity (up to 0.8 kg nh(4)(+)-n m(-3) day(-1)). a planctomycetales-specific 16s rrna gene library was constructed to analyse the diversity of the anaerobic ammonium-oxidizing bacteria (anaob). most of the specifically amplified sequences (15/16) were similar to each other (> 99%) but were distan ... | 2008 | 18479446 |
| use of quantitative real-time pcr to monitor population dynamics of ammonia-oxidizing bacteria in batch process. | a quantitative real-time pcr (qpcr) assay with the taqman system was used to quantify 16s rrna genes of beta-proteobacterial ammonia-oxidizing bacteria (aob) in a batch nitrification bioreactor. five different sets of primers, together with a taqman probe, were used to quantify the 16s rrna genes of beta-proteobacterial aob belonging to the nitrosomonas europaea, nitrosococcus mobilis, nitrosomonas nitrosa, and nitrosomonas cryotolerans clusters, and the genus nitrosospira. we also used pcr foll ... | 2008 | 18712556 |
| ammonia-dependent differential regulation of the gene cluster that encodes ammonia monooxygenase in nitrosococcus oceani atcc 19707. | molecular analysis of the ammonia monooxygenase-encoding gene cluster in nitrosococcus oceani revealed that the amo genes are differentially expressed from three promoters dependent on the external ammonia concentration. whereas a distal amorcabd operon promoter, pc1, is active only in the presence of ammonia, identified proximal amoc (pc2) and amoa (pa) sigma-70-type promoters are constitutive. promoter region pc2 also contains a consensus sequence for binding of rpon, usually involved in nitro ... | 2008 | 18973622 |
| activated packed bed bioreactor for rapid nitrification in brackish water hatchery systems. | a packed bed bioreactor (pbbr) was developed for rapid establishment of nitrification in brackish water hatchery systems in the tropics. the reactors were activated by immobilizing ammonia-oxidizing (amonpcu-1) and nitrite-oxidizing (nionpcu-1) bacterial consortia on polystyrene and low-density polyethylene beads, respectively. fluorescence in situ hybridization demonstrated the presence of autotrophic nitrifiers belong to nitrosococcus mobilis, lineage of beta ammonia oxidizers and nitrite oxid ... | 2009 | 19039611 |
| composition and diversity of ammonia-oxidising bacterial communities in wastewater treatment reactors of different design treating identical wastewater. | autotrophic ammonia-oxidising bacteria (aob) are a crucial component of the microbial communities of nitrifying wastewater treatment systems. nitrification is known to occur in reactors of different configuration, but whether aob communities are different in reactors of different design is unknown. we compared the diversity and community structure of the betaproteobacterial aob in two full-scale treatment reactors - a biological aerated filter (baf) and a trickling filter - receiving the same wa ... | 2003 | 19719680 |
| [community structure and kinetics characterization of enriched nitrifiers cultivated with reject water]. | the community of nitrifiers cultivated with reject water were investigated by fluorescent in situ hybridization (fish) performed with 16s rrna-targeted oligonucleotide probes, and the kinetic properties such as temperature correction factor taun and the half saturation coefficient k(n) were also investigated. the results showed that the percentage of ammonia oxidizing bacteria (aob) and nitrite oxidizing bacteria (nob) in the activated sludge was 15.7% +/- 3.7% and 12.9% +/- 3.2%, nitrosomonas e ... | 2009 | 19775004 |
| nitrification in brackish water recirculating aquaculture system integrated with activated packed bed bioreactor. | recirculation aquaculture systems (ras) depend on nitrifying biofilters for the maintenance of water quality, increased biosecurity and environmental sustainability. to satisfy these requirements a packed bed bioreactor (pbbr) activated with indigenous nitrifying bacterial consortia has been developed and commercialized for operation under different salinities for instant nitrification in shrimp and prawn hatchery systems. in the present study the nitrification efficiency of the bioreactor was t ... | 2010 | 20150717 |
| [comparative analysis of primer-based pcr strategies for characterizing ammonia-oxidizing bacterial communities in lake sediments]. | pcr-based techniques are commonly used to characterize ammonia-oxidizing bacterial (aob) communities, but are subjected to the bias induced by pcr primers. in this study, the sensitivity and specificity of two pairs of primer were assessed based on a group of lake sediment samples. compared to the low sensitivity of the cto primer, the betaamo primer produced intensive single bands in all samples tested. however, the sequences retrieved from one of the samples by betaamo did not cluster with nit ... | 2010 | 21072943 |
| nitrosococcus watsonii sp. nov., a new species of marine obligate ammonia-oxidizing bacteria that is not omnipresent in the world's oceans: calls to validate the names 'nitrosococcus halophilus' and 'nitrosomonas mobilis'. | local associations between anammox bacteria and obligate aerobic bacteria in the genus nitrosococcus appear to be significant for ammonia oxidation in oxygen minimum zones. the literature on the genus nitrosococcus in the chromatiaceae family of purple sulfur bacteria (gammaproteobacteria, chromatiales) contains reports on four described species, nitrosococcus nitrosus, nitrosococcus oceani, 'nitrosococcus halophilus' and 'nitrosomonas mobilis', of which only n. nitrosus and n. oceani are validl ... | 2011 | 21204874 |
| bacterial community structure of a full-scale biofilter treating pig house exhaust air. | biological air filters represent a promising tool for treating emissions of ammonia and odor from pig facilities. quantitative fluorescence in situ hybridization (fish) and 16s rrna gene sequencing were used to investigate the bacterial community structure and diversity in a full-scale biofilter consisting of two consecutive compartments (front and back filter). the analysis revealed a highly specialized bacterial community of limited diversity, dominated by a few groups of betaproteobacteria (e ... | 2011 | 21514081 |
| characterizing bacterial gene expression in nitrogen cycle metabolism with rt-qpcr. | recent advances in dna sequencing have greatly accelerated our ability to obtain the raw information needed to recognize both known and potential novel modular microbial genomic capacity for nitrogen metabolism. with pcr-based approaches to quantifying microbial mrna expression now mainstream in most laboratories, researchers can now more efficiently propose and test hypotheses on the contributions of individual microbes to the biological accessibility of nitrogen upon which all other life depen ... | 2011 | 21514471 |
| effect of salinity on hydroxylamine oxidation in a marine ammonia-oxidizing gammaproteobacterium, nitrosococcus oceani strain ns58: molecular and catalytic properties of tetraheme cytochrome c-554. | tetraheme cytochrome c-554 is a physiological electron acceptor of hydroxylamine oxidoreductase (hao), a core enzyme of ammonia oxidation in chemoautotrophic nitrifiers. here we report the purification of cytochrome c-554 from nitrosococcus oceani strain ns58, a marine gammaproteobacterial ammonia-oxidizing bacterium. the ns58 cytochrome is a 25 kda-protein having four hemes c. the absorption spectrum of the cytochrome showed peaks at 420 nm, 523 nm, and 554 nm, with shoulders at around 430 nm a ... | 2010 | 21576859 |