water as the source of oxidant and reductant in bacterial chemosynthesis. 19655217465
phosphate requirements of the nitrifying bacteria. 19675299910
fine structure and the localization of the nitrite oxidizing system in nitrobacter winogradskyi. 19685304022
nitrification. 19665326519
[morphological and physiological studies of nitrobacter winogradsi buch]. 19695383861
effect of sodium, manganese and zinc on the activity of nitrobacter agilis. 19695395141
effect of some vitamins on nitrite oxidation by nitrobacter agilis. 19695395935
intermediary metabolism of carbon compounds by nitrifying bacteria. 19705426270
[interrelationship between light and chemosynthesis in nitrobacter winogradskyi]. 19705437117
particulate formate oxidase from nitrobacter agilis. 19705471292
effects of some phenylamide herbicides and their degradation products on soil nitrification. 19705471337
calorimetric determination of free energy efficiency in nitrobacter winogradskyi. 19705516608
changes in cytochrome content and turnover number during growth of nitrobacter. 19715541690
autotrophic growth and synthesis of reserve polymers in nitrobacter winogradskyi. 19715552133
[ph-metric determination of oxidative phosphorylation in whole cells of nitrobacter winogradskyi buch]. 19675600789
inhibition of nitrifying chemolithotrophic bacteria by several insecticides. 19685636842
acetate assimilation by nitrobacter agilis in relation to its "obligate autotrophy".acetate (1 to 10 mm) had no effect on the rate of nitrite oxidation or exponential growth by nitrobacter agilis. however, acetate-1-(14)c and -2-(14)c were both assimilated by growing cultures, and acetate carbon contributed 33 to 39% of newly synthesized cell carbon. carbon from acetate was incorporated into all of the major cell constituents, including most of the amino acids of cell protein and poly-beta-hydroxybutyrate (phb). cultures grown in the presence of acetate showed a significant inc ...19685643062
deoxyribonucleic acid base composition and taxonomy of thiobacilli and some nitrifying bacteria. 19685677980
the effect of dd nematocide on soil micro-organisms. 19685679913
minimal size of nitrobacter membrane fragments retaining nitrite oxidizing activity. 19685706429
[ph-metrical studies on the phosphate metabolism in living cells of nitrobacter winogradskyi buch]. 19685709642
effect of some organic acids on nitrification by nitrobacter agilis. 19685757170
effect of some polyhydric alcohols on nitrification by nitrobacter agilis. 19685757178
effect of some rare elements on nitrification by nitrate-forming bacteria in soil suspension. 19685761529
[studies on the calcium and potassium requirements of nitrobacter winogradskyi buch]. 19695766673
ultrastructure of nitrobacter agilis grown under autotrophic and heterotrophic conditions.nitrobacter agilis, grown through seven transfers heterotrophically in the absence of nitrite, was examined in the electron microscope. the ultrastructure of such cells closely resembled that of autotrophically grown n. agilis. it was thus futher established that the organisms growing heterotrophically were indeed n. agilis and, therefore, that n. agilis is a facultative autotroph. acetate incorporation into poly-beta-hydroxybutyrate was confirmed cytologically.19695773036
the action spectrum of hemoprotein oxidase in nitrobacter agilis. 19695787691
inhibition of nitrifying bacteria by grass and forb root extracts. 19695798521
nitrite oxidase and nitrate reductase in nitrobacter agilis.nitrite oxidase and nitrate reductase in nitrobacter agilis were shown to be separate enzymes. the best separation of the two systems was achieved by ammonium sulphate fractionation. the effects of various compounds, including antimycin a, 2-n-heptyl-4-hydroxyquinoline n-oxide and chlorate, also clearly distinguish between the two enzyme reactions. the relationship between the two opposing reactions in nitrobacter is discussed.19695807206
fatty acids in the lipids of marine and terrestrial nitrifying bacteria.fatty acids in the lipids of 19 marine and terrestrial nitrifying bacteria have been analyzed. ammonia-oxidizing bacteria have a very simple acid composition; palmitic and palmitoleic acid account for 96 to 100% of the total acids. the fatty acids of nitrite-oxidizing bacteria cover a wider range, from c(14) to c(19), but from two to four acids still account for more than 80% of the total acids. branched iso- and anteiso-acids are present in traces only in 2 of the 19 bacteria. the chemical and ...19695808068
the mechanism of nitrite oxidation by nitrobacter winogradskyi. 19665940631
growth of some chemoautotrophic bacteria at different oxygen tensions. 19665955989
formate utilization by nitrobacter winogradskyi. 19665964975
oxygen-nitrogen relationships in autotrophic nitrification.oxygen utilization by the autotrophic nitrifiers nitrosomonas and nitrobacter was studied. experimental evidence is presented which reflects the effect of carbon dioxide fixation on overall oxygen utilization in autotrophic nitrification. measurement of dissolved oxygen and inorganic nitrogen changes indicates that oxygen-nitrogen ratios in inorganic nitrogen oxidation are equal to 3.22 parts (expressed in milligrams per liter) of oxygen per part of ammonia nitrogen oxidized to nitrite nitrogen ...19676077417
a relationship between prokaryote and eukaryote observed in nitrobacter agilis cytochromes aa3 and c.cytochrome aa3 (cytochrome c oxidase) and cytochrome c were purified from nitrobacter agilis, and some of their properties were compared with those of the respective counterparts of eukaryote from the evolutionary point of view. n. agilis cytochrome aa3 has many functional and structural properties similar to those of eukaryotic cytochrome aa3, although its molecule is composed of only two kinds of subunits unlike the eukaryotic cytochrome which is composed of 7 kinds of subunits. n. agilis cyto ...19846087241
cytochrome oxidase of nitrobacter agilis: isolation by hydrophobic interaction chromatography.cytochrome oxidase has been purified from nitrobacter agilis using hydrophobic interaction chromatography. the purified preparation contained 3-5% phospholipid and migrated as a single band during polyacrylamide gel electrophoresis under nondissociating conditions, but appeared as three bands in the presence of sodium dodecyl sulfate and 6 m urea. these three bands corresponded to molecular weights of 37 000, 25 000, and 13 000. the absorption spectra of cytochrome oxidase isolated from nitrobac ...19806260319
molecular and enzymatic properties of "cytochrome aa3"-type terminal oxidase derived from nitrobacter agilis.cytochrome c oxidase (cytochrome aa3-type) [ec] was purified from nitrobacter agilis to an electrophoretically homogeneous state and some of its properties were studied. the enzyme showed absorption peaks at 422, 598, and 840 nm in the oxidized form, and at 442 and 606 nm in the reduced form. the co compound of the reduced enzyme showed peaks at 436 and 604 nm, and the latter peak had a shoulder at 599 nm. the enzyme possessed 1 mol of heme a and 1.6 g-atom of copper per 41,000 g, and wa ...19816260762
respiration-dependent proton translocation in nitrosomonas europaea and its apparent absence in nitrobacter agilis during inorganic oxidations.oxygen pulse experiments were carried out with the nitrifying bacteria nitrosomonas europaea and nitrobacter agilis and with spheroplasts and everted vesicles prepared from nitrobacter agilis. in addition to thiocyanate, the salting-in anions perchlorate and trichloroacetate proved to be permeant and effective in allowing respiration-dependent proton translocation with nitrosomonas europaea. valinomycin-k+, however, was generally ineffective in this respect with nitrosomonas europaea. the observ ...19826277846
the complete amino acid sequence of nitrobacter agilis cytochrome c-550.the amino acid sequence of cytochrome c-550 from the chemoautotroph, nitrobacter agilis, was completed by using solid-phase sequencing and conventional procedures. the cytochrome was composed of 109 amino acid residues and its molecular weight was calculated to be 12375 including haem c. the cytochrome was homologous to eukaryotic cytochromes c and some photosynthetic bacterial cytochromes c2. in particular, its primary structure was very similar to that of rhodopseudomonas viridis cytochrome c2 ...19826291614
unusual lipid a types in phototrophic bacteria and related species.photosynthetic bacteria of the rhodospirillaceae family (sulfur-free purple bacteria) possess lipopolysaccharides (lps) that deviate markedly from the salmonella lipopolysaccharides in the chemical makeup of the lipid a component and in their biologic properties. lps of rhodopseudomonas gelatinosa is highly toxic and pyrogenic, while that of rhodospirillum tenue shows cryptic toxicity. two lps types are completely non-toxic. the rhodopseudomonas sphaeroides lipid a has the same backbone as that ...19846474014
source of the oxygen atoms of nitrate in the oxidation of nitrite by nitrobacter agilis and evidence against a p-o-n anhydride mechanism in oxidative phosphorylation.15n, 18o tracer studies were applied to the aerobic oxidation of nitrite to nitrate by the chemolithotrophic bacterium, nitrobacter agilis. it was established that, in conversion of nitrite to nitrate, one oxygen atom of nitrate arose from water and none from o2 or inorganic phosphate. this result confirms that of kumar et al. [(1983) febs lett. 152, 71-74]. oxygen exchange between water and inorganic phosphate was small and that between water and nitrite or nitrate or any reaction intermediates ...19846486809
hybrid biosensor for clinical and fermentation process control. 19846596903
na+ and k+ transport in nitrosomonas europaea and nitrobacter agilis.potassium-depleted cells of nitrosomonas europaea and nitrobacter agilis were prepared by diethanolamine treatment and contained less than 5 mm intracellular k+. the addition of k+ to k+-depleted cells of n. europaea and n. agilis resulted in a depolarization of membrane potential (delta psi) by about 5 and 10 mv, respectively. this depolarization was, however, compensated by an equivalent increase in transmembrane ph gradient (delta ph), so that the total proton-motive force (delta p) remained ...19846733088
effects of polychlorinated biphenyls and environmental biotransformation products on aquatic nitrification.the effects of polychlorinated biphenyls (pcbs) on nitrification were examined for pure cultures and natural reservoir samples. pcbs at concentrations greater than 10 microgram liter-1 inhibited nitrification, principally ammonium oxidation, in one of two natural reservoir environments. however, this inhibition could not be reproduced in pure high-cell-density cultures or in previously contaminated reservoir waters. a pcb environmental biotransformation product, p-chlorophenylglyoxylic acid, and ...19826805434
proton electrochemical gradients in washed cells of nitrosomonas europaea and nitrobacter agilis.the components of the proton motive force (deltap), namely, membrane potential (deltapsi) and transmembrane ph gradient (deltaph), were determined in the nitrifying bacteria nitrosomonas europaea and nitrobacter agilis. in these bacteria both deltapsi and deltaph were dependent on external ph. thus at ph 8.0, nitrosomonas europaea and nitrobacter agilis had deltapsi values of 173 mv and 125 mv (inside negative), respectively, as determined by the distribution of the lipophilic cation [(3)h]tetra ...19836833187
definitive 15n nmr evidence that water serves as a source of 'o' during nitrite oxidation by nitrobacter agilis. 19836840279
[bacterial colonization following resective and non-resective stomach-surgery (author's transl)].studies on why there is a higher disposition of carcinoma developing in the residual portion of the stomach of patients having undergone resections have led to the assumption that bacterial colonization constitutes a co-carcinogenic factor. it has been the purpose of this investigation to compare the ensuing bacterial growth following resective and nonresective stomach surgery. 120 sprague-dawley rats were divided into six groups: 1) control group: laparotomy. (2)spv: with assured preservation o ...19827064494
acceleration by montmorillonite of nitrification in soil.a soil naturally containing montmorillonite (m) was amended with 10% m and sequentially perfused with glyeme, with fresh glyeme being added every 16--17d after nitrification of the previously added glycine-nitrogen had reached a plateau. in some systems, the old perfusates were replaced each time with a fresh glycine solution; in others, the initial perfusate was not replaced but only adjusted each time to the original 200 ml volume and a comparable glycine concentration (140 micrograms nh2-n/ml ...19807380363
effect of temperature on nitrification intensity in soil.the temperature dependence of nitrification can be expressed by the arrhenius equation while the time course of nitrate production can be expressed by the gomperz function. these two findings served as a basis for a mathematical model which makes it possible to calculate nitrate production in the soil even when the temperature changes once or more times during the incubation.19807380364
nitrification reactions in a column of soil with a flowing nutrient solution. 19807380365
effect of montmorillonite and kaolinite on nitrification in soil.a soil not naturally containing montmorillonite (m) was amended with approximately 5, 10 or 20% m or kaolinite (k), maintained in a greenhouse under periodic cultivating and alternate wetting and drying of more than two years, and then used in perfusion studies. the incorporation of m enhanced the rate of both heterotrophic degradation of glycine and subsequent autotrophic nitrification in direct relation to the amounts of m added. in soil amended with k, neither degradation nor nitrification wa ...19807380366
sequential nitrification by an alcaligenes sp. and nitrobacter agilis.the ecological importance of heterotrophic nitrification has been difficult to assess because of low levels of nitrification associated with this phenomenon. nitrification by a soil isolate, an alcaligenes sp., which oxidizes pyruvic oxime to produce up to 1867 mg nitrite-nitrogen/l, is described. sequential nitrification with the chemoautotroph nitrobacter agilis, atcc 14123, resulted in nitrate accumulation and a concomitant decrease of the nitrite produced by the alcaligenes sp. when the bact ...19807459725
genetic and phenetic analyses of bradyrhizobium strains nodulating peanut (arachis hypogaea l.) roots.seventeen bradyrhizobium sp. strains and one azorhizobium strain were compared on the basis of five genetic and phenetic features: (i) partial sequence analyses of the 16s rrna gene (rdna), (ii) randomly amplified dna polymorphisms (rapd) using three oligonucleotide primers, (iii) total cellular protein profiles, (iv) utilization of 21 aliphatic and 22 aromatic substrates, and (v) intrinsic resistances to seven antibiotics. partial 16s rdna analysis revealed the presence of only two rdna homolog ...19957538280
a new obligately chemolithoautotrophic, nitrite-oxidizing bacterium, nitrospira moscoviensis sp. nov. and its phylogenetic relationship.a gram-negative, non-motile, non-marine, nitrite-oxidizing bacterium was isolated from an enrichment culture initiated with a sample from a partially corroded area of an iron pipe of a heating system in moscow, russia. the cells were 0.9-2.2 microns x 0.2-0.4 microns in size. they were helical- to vibroid-shaped and often formed spirals with up to three turns 0.8-1.0 micron in width. the organism possessed an enlarged periplasmic space and lacked intracytoplasmic membranes and carboxysomes. the ...19957646315
biotreatment of ammonia- and butanal-containing waste gases.the biological removal of ammonia and butanal in contaminated air was investigated by using, respectively, a laboratory-scale filter and a scrubber-filter combination. it was shown that ammonia can be removed with an elimination efficiency of 83% at a volumetric load of 100 m3.m-2.h-1 with 4-16 ppm of ammonia. during the experiment percolates were analysed for nitrate, nitrite, ammonium and ph. it was found that the nitrification in the biofilter could deteriorate due to an inhibition of nitroba ...19947765814
detection and counting of nitrobacter populations in soil by pcr.although the biological conversion of nitrite to nitrate is a well-known process, studies of nitrobacter populations are hindered by their physiological characteristics. this report describes a new method for detecting and counting nitrobacter populations in situ with the pcr. two primers from the 16s rrna gene were used to generate a 397-bp fragment by amplification of nitrobacter species dna. no signal was detected from their phylogenetic neighbors or the common soil bacteria tested. extractio ...19957793930
[the endotoxins of gram-negative bacteria: their structure and biological role].main attention in the paper is paid to the study of lipid a, a component possessing endotoxic activity. lipids a containing glucosamine disaccharide (representatives of enterobacteriaceae family), and variants of lipid a differing from the toxic one either in the structure of carbohydrate core or in the spectrum of fatty acids are considered. they are either phototrophic, nodulating (bradyrhyzobium species) or soil species (nitrobacter and thiobacillus) bacteria. lipid a from lipopolysaccharides ...19947952230
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 ...19947961414
iron metabolism in rhodobacter capsulatus. characterisation of bacterioferritin and formation of non-haem iron particles in intact cells.the water-soluble cytochrome b557 from the photosynthetic bacterium rhodobacter capsulatus was purified and shown to have the properties of the iron-storage protein bacterioferritin. the molecular mass of r. capsulatus bacterioferritin is 428 kda and it is composed of a single type of 18-kda subunit. the n-terminal amino acid sequence of the bacterioferritin subunit shows 70% identity to the sequence of bacterioferritin subunits from escherichia coli, nitrobacter winogradskyi, azotobacter vinela ...19948055962
effects of herbicides and fumigants on microbial activities in soil. 19948069060
molecular phylogenetic analysis of nitrobacter spp.the phylogeny of bacteria belonging to the genus nitrobacter was investigated by sequencing the whole 16s rrna gene. the average level of similarity for the three nitrobacter strains examined was high (99.2%), and the similarity level between nitrobacter winogradskyi and nitrobacter sp. strain ll, which represent two different genomic species, was even higher (99.6%). when all of the nitrobacter strains and their phylogenetic neighbors bradyrhizobium and rhodopseudomonas species were considered, ...19948123564
tolerance of nitrobacter to toxicity of some nigerian crude oils. 19948142709
biological nitrogen removal from wastewater.a review of the research on the kinetics of nitrification and denitrification is presented including an explanation of reaction engineering models. the results of laboratory scale experiments with high rate nitrification processes are discussed using kinetic results for oxygen limitation as well as for substrate limitation and inhibition. it can be demonstrated that reaction engineering models are helpful for a better understanding of the processes and for the design of reactors. pilot scale inv ...19948165950
close genetic relationship between nitrobacter hamburgensis nitrite oxidoreductase and escherichia coli nitrate reductases.the nitrite oxidoreductase (nor) from the facultative nitrite-oxidizing bacterium nitrobacter hamburgensis x14 was investigated genetically. in order to develop a probe for the gene norb, the n-terminal amino acid sequence of the nor beta-subunit (norb) was determined. based on that amino acid sequence, an oligonucleotide was derived that was used for the identification and cloning of gene norb. sequence analysis of dna fragments revealed three adjacent open reading frames in the order nora, nor ...19938297210
membrane-bound cytochrome c is an alternative electron donor for cytochrome aa3 in nitrobacter winogradskyi.we purified membrane-bound cytochrome c-550 [cytochrome c-550(m)] to an electrophoretically homogeneous state from nitrobacter winogradskyi. the cytochrome showed peaks at 409 and 525 nm in the oxidized form and peaks at 416, 521, and 550 nm in the reduced form. the molecular weight of the cytochrome was estimated to be 18,400 on the basis of protein and heme c contents and 18,600 by gel filtration. the n-terminal amino acid sequence of cytochrome c-550(m) was determined to be a-p-t-s-a-a-d-a-e- ...19938392510
effect of nematicides, telone ii and vorlex, on microflora and nitrification in tobacco soil. 19938418937
monoclonal antibodies recognizing nitrite oxidoreductase of nitrobacter hamburgensis, n. winogradskyi, and n. vulgaris.three monoclonal antibodies (mabs) against nitrite oxidoreductase (nor) of nitrobacter hamburgensis were produced. sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting analysis of the purified enzyme showed that the mabs named hyb 153.1 and hyb 153.3 both recognized a protein with a molecular mass of 64,000 da, while hyb 153.2 recognized a protein with a molecular mass of 115,000 da. the molecular masses of these proteins are in the same range as those of the proteins of ...19968779572
phylogenetic probes for analyzing abundance and spatial organization of nitrifying bacteria.a hierarchical set of five 16s rrna-targeted oligonucleotide dna probes for phylogenetically defined groups of autotrophic ammonia- and nitrite-oxidizing bacteria was developed for environmental and determinative studies. hybridization conditions were established for each probe by using temperature dissociation profiles of target and closely related nontarget organisms to document specificity. environmental application was demonstrated by quantitative slot blot hybridization and whole-cell hybri ...19968787412
nitrobacter winogradskyi cytochrome c oxidase genes are organized in a repeated gene cluster.cytochrome c oxidase (ec is one of the components of the electron transport chain by which nitrobacter, a facultative lithoautotrophic bacterium, recovers energy from nitrite oxidation. the genes encoding the two catalytic core subunits of the enzyme were isolated from a nitrobacter winogradskyi gene library. sequencing of one of the 14 cloned dna segments revealed that the subunit genes are side by side in an operon-like cluster. remarkably the cluster appears to be present in at least ...19968836428
structure and function of a nitrifying biofilm as determined by in situ hybridization and the use of microelectrodes.microprofiles of o2 and no3- were measured in nitrifying biofilms from the trickling filter of an aquaculture water recirculation system. by use of a newly developed biosensor for no3-, it was possible to avoid conventional interference from other ions. nitrification was restricted to a narrow zone of 50 microns on the very top of the film. in the same biofilms, the vertical distributions of members of the lithoautotrophic ammonia-oxidizing genus nitrosomonas and of the nitrite-oxidizing genus n ...19968953735
isolation and immunocytochemical location of the nitrite-oxidizing system in nitrospira moscoviensisa membrane-associated nitrite-oxidizing system of nitrospira moscoviensis was isolated from heat-treated membranes. the four major proteins of the enzyme fraction had apparent molecular masses of 130, 62, 46, and 29 kda, respectively. the nitrite-oxidizing activity was dependent on the presence of molybdenum. in contrast to the nitrite oxidoreductase of nitrobacter hamburgensis x14, the activity of the nitrite-oxidizing system of ns. moscoviensis increased when solubilized by heat treatment. ele ...19989477257
microbiology of a nitrite-oxidizing bioreactor.the microbiology of the biomass from a nitrite-oxidizing sequencing batch reactor (nosbr) fed with an inorganic salts solution and nitrite as the sole energy source that had been operating for 6 months was investigated by microscopy, by culture-dependent methods, and by molecular biological methods, and the seed sludge that was used to inoculate the nosbr was investigated by molecular biological methods. the nosbr sludge comprised a complex and diverse microbial community containing gram-negativ ...19989572966
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 ...19989687471
identification and activities in situ of nitrosospira and nitrospira spp. as dominant populations in a nitrifying fluidized bed reactor.bacterial aggregates from a chemolithoautotrophic, nitrifying fluidized bed reactor were investigated with microsensors and rrna-based molecular techniques. the microprofiles of o2, nh4+, no2-, and no3- demonstrated the occurrence of complete nitrification in the outer 125 microgram of the aggregates. the ammonia oxidizers were identified as members of the nitrosospira group by fluorescence in situ hybridization (fish). no ammonia- or nitrite-oxidizing bacteria of the genus nitrosomonas or nitro ...19989726900
isolation and characterization of a novel facultatively alkaliphilic nitrobacter species, n. alkalicus sp. nov.five strains of lithotrophic, nitrite-oxidizing bacteria (an1-an5) were isolated from sediments of three soda lakes (kunkur steppe, siberia; crater lake and lake nakuru, kenya) and from a soda soil (kunkur steppe, siberia) after enrichment at ph 10 with nitrite as sole electron source. morphologically, the isolates resembled representatives of the genus nitrobacter. however, they differed from recognized species of this genus by the presence of an additional s-layer in their cell wall and by the ...19989818354
organic halogen removal from chlorinated humic ground water and lake water by nitrifying fluidized-bed biomass characterised by electron microscopy and molecular methods.the dechlorinating and genotoxicity-removing activities of nitrifying fluidized-bed reactor biomass towards chlorinated organic compounds in water were shown at level below 1 ppm. the removal rates of adsorbable organic halogens were 200 micrograms cl (g vs day)-1 for chlorinated humic ground water and 50 micrograms cl (g vs day)-1 for chlorinated lake water when studied in batch mode. in a sequenced batch mode the removal rates [micrograms cl (g vs day)-1] were 2000 from chlorohumus, 1400-1800 ...19989866179
an amperometric enzyme-linked immunosensor for nitrobacter.a new amperometric enzyme-linked immunoassay for specific enumeration of nitrobacter has been developed. this assay uses an electrode made of glassy carbon, on which the immunological reaction is carried out. the method is based on a competitive immunoassay principle, utilising monoclonal primary antibody and alkaline-phosphatase-labelled secondary antibody. the enzyme substrate 5-bromo-4-chloro-3-indolyl phosphate generates an electroactive product which is amperometrically detected. the effect ...19989891931
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 ...199910049622
assessment of three methods for detection and quantification of nitrite-oxidizing bacteria and nitrobacter in freshwater sediments (mpn-pcr, mpn-griess, immunofluorescence).> abstract nitrification in freshwater, a key process in the nitrogen cycle, is now well known to take place predominantly on suspended particles and in sediment. nitrobacter is the most commonly isolated nitrite oxidizing bacteria from water environments. three methods for counting nitrite oxidizing communities (especially nitrobacter) in sediment were investigated: mpn-griess, fluorescent antibodies (immunofluorescence), and a more recent molecular method coupling specific dna amplification by ...199910227878
maintenance energy demand and starvation recovery dynamics of nitrosomonas europaea and nitrobacter winogradskyi cultivated in a retentostat with complete biomass retention.nitrosomonas europaea and nitrobacter winogradskyi (strain "engel") were grown in ammonia-limited and nitrite-limited conditions, respectively, in a retentostat with complete biomass retention at 25 degrees c and ph 8. fitting the retentostat biomass and oxygen consumption data of n. europaea and n. winogradskyi to the linear equation for substrate utilization resulted in up to eight-times-lower maintenance requirements compared to the maintenance energy demand (m) calculated from chemostat expe ...199910347029
in situ analysis of nitrifying biofilms as determined by in situ hybridization and the use of microelectrodes.we investigated the in situ spatial organization of ammonia-oxidizing and nitrite-oxidizing bacteria in domestic wastewater biofilms and autotrophic nitrifying biofilms by using microsensors and fluorescent in situ hybridization (fish) performed with 16s rrna-targeted oligonucleotide probes. the combination of these techniques made it possible to relate in situ microbial activity directly to the occurrence of nitrifying bacterial populations. in situ hybridization revealed that bacteria belongin ...199910388720
identification of nitrite-oxidizing bacteria with monoclonal antibodies recognizing the nitrite oxidoreductase.immunoblot analyses performed with three monoclonal antibodies (mabs) that recognized the nitrite oxidoreductase (nor) of the genus nitrobacter were used for taxonomic investigations of nitrite oxidizers. we found that these mabs were able to detect the nitrite-oxidizing systems (nos) of the genera nitrospira, nitrococcus, and nitrospina. the mab designated hyb 153-2, which recognized the alpha subunit of the nor (alpha-nor), was specific for species belonging to the genus nitrobacter. in contra ...199910473425
microscale diversity of the genus nitrobacter in soil on the basis of analysis of genes encoding rrna.we looked at the diversity of [no(2)](-) oxidizers at field scale by examining isolates at clump scale and in microsamples of soil (diameter, 50 microm). the genetic distances (as determined by amplified ribosomal dna restriction analysis performed with nitrobacter-specific primers) in a small clump of soil were as large as those between reference strains from large geographical areas. diversity in individual microsamples was shown by serotyping.200011010914
application of an amperometric immunosensor for the enumeration of nitrobacter in activated sludge.a competitive immunosensor using a monoclonal antibody has been developed for the enumeration of nitrobacter in activated sludge and other environmental samples. its cross-reactivity was tested against a number of bacterial strains and isolates. all strains of the nitrite-oxidising genera nitrobacter and nitrococcus reacted strongly with the monoclonal antibody. the nitrite-oxidising nitrospira moscoviensis, as well as the ammonia oxidising bacteria and the heterotrophic bacteria tested, did not ...200011030580
high-resolution phylogenetic analysis of no2--oxidizing nitrobacter species using the rrs-rrl igs sequence and rrl genes.a high-resolution phylogenetic analysis of nitrobacter strains and their neighbours was made using the rrs-rrl intergenic spacer sequence and the hypervariable part of the rrl gene. the phylogenetic tree obtained was consistent with that which was obtained previously but was much more discriminating, permitting the design of genus-specific primers.200011034501
energy model and metabolic flux analysis for autotrophic nitrifiers.the behavior of pure cultures of nitrifying microorganisms under autotrophic growth operating conditions was investigated and the relations between their energy metabolism and their anabolism analyzed by means of metabolic network computation. the description of the metabolism of the nitrifiers is extended to their energy metabolism by introducing compartmentalization (cytoplasmic and periplasmic sides) and studying coupling between the electron transport chain and the proton gradient generation ...200111180062
phylogenetic and dna-dna hybridization analyses of bradyrhizobium species.the 16s rdna sequence of bradyrhizobium liaoningense was determined and analysed together with sequences of other bradyrhizobium species and related taxa. in addition, dna-dna hybridizations were performed between representative strains of the three bradyrhizobium species. bradyrhizobium liaoningense is genotypically highly related to bradyrhizobium japonicum, whereas bradyrhizobium elkanii is more distantly related to these two species. the fact that afipia, agromonas, blastobacter, nitrobacter ...200111211247
microenvironments and distribution of nitrifying bacteria in a membrane-bound biofilm.the distribution of nitrifying bacteria of the genera nitrosomonas, nitrosospira, nitrobacter and nitrospira was investigated in a membrane-bound biofilm system with opposed supply of oxygen and ammonium. gradients of oxygen, ph, nitrite and nitrate were determined by means of microsensors while the nitrifying populations along these gradients were identified and quantified using fluorescence in situ hybridization (fish) in combination with confocal laser scanning microscopy. the oxic part of th ...200011214800
development of nitrification inhibition assays using pure cultures of nitrosomonas and nitrobacter.restricted requirements for nitrogen reduction at wastewater treatment plants have increased the need for assays determining the inhibition of nitrification. in this paper, two new assays studying ammonia oxidation and nitrite oxidation, respectively, are presented. as test organisms, pure cultures of nitrosomonas and nitrobacter isolated from activated sludge are used. the assays are performed in test tubes where the bacteria are incubated with the compound or wastewater to be tested. the nitri ...200111228996
simultaneous carbon and nitrogen removal from high strength domestic wastewater in an aerobic rbc biofilm.high strength domestic wastewater discharges after no/partial treatment through sewage treatment plants or septic tank seepage field systems have resulted in a large build-up of groundwater nitrates in rajasthan, india. the groundwater table is very deep and nitrate concentrations of 500-750 mg/l (113-169 as no3(-)-n) are commonly found. a novel biofilm in a 3-stage lab-scale rotating biological contactor (rbc) was developed by the incorporation of a sulphur oxidising bacterium thiosphaera panto ...200111329673
nitrogen transformation during organic waste composting by the rutgers system and its effects on ph, ec and maturity of the composting mixtures.the evolution of the different forms of nitrogen during the composting of several wastes was studied, as well as its relation to the ph, electrical conductivity and parameters of maturity of the composts obtained. four mixtures were prepared from different organic materials: sewage sludge, municipal solid waste, brewery sludge, sorghum bagasse, cotton waste and pine bark. the evolution of the different forms of nitrogen during composting depended on the material which supplied the nitrogen to th ...200111341692
implementation, study and calibration of a modified asm2d for the simulation of sbr enhanced process model for sbrs has been developed. though the basic mechanism largely draws on the activated sludge model n. 2d, its new features are the splitting of the nitrification stage in a two-step process, according to the well known nitrosomonas-nitrobacter oxidation sequence, and an improved xpao dynamics, involved in the anaerobic/aerobic phosphorus removal process. the model was implemented through the dll technique allowing complied c++ modules to be linked to an ordinary simuli ...200111381934
enhancement of nitrifying biofilm formation using selected eps produced by heterotrophic bacteria.the possibility of enhancing nitrifying biofilm formation rate with the aid of selected eps produced by heterotrophic bacteria was investigated. when eps production characteristics were examined for four kinds of heterotrophs isolated from a domestic wastewater treatment reactor, two strains obtained from biofilms (b1, b2) exhibited a higher polysaccharide production rate than those from suspended flocs (a1, a2). among eps components, the concentration of uronic acids gave a good correlation wit ...200111381968
analysis of microbial structure and function of nitrifying biofilms. 200111398431
in situ reverse transcription to detect the cbbl gene and visualize rubisco in chemoautotrophic nitrifying situ methodologies targeting the cbbl gene were used to visualize cells of nitrifying bacteria. both procaryotic in situ pcr (is-pcr) and in situ reverse transcription (isrt) protocols were employed to determine gene presence and expression, respectively.200111412349
soft particle analysis of bacterial cells and its interpretation of cell adhesion behaviors in terms of dlvo theory.the electrokinetic properties of two nitrifying strains, nitrosomonas europaea and nitrobacter winogradskyi, and three heterotrophic bacteria, escherichia coli, pseudomonas putida and pseudomonas aeruginosa, were examined by electrophoretic mobility measurement and analyzed using the soft particle electrophoresis theory that is suitable for biological particles. the bacterial adhesion characteristics onto glass bead substratum were also evaluated by packed bed method. the mobility of the bacteri ...200111451661
factors affecting nitrite build-up in nitrifying biofilm reactor.nitrite build-up in a nitrifying biofilm reactor for direct denitrification from the nitrite stage was investigated. at least three factors were found to influence the nitrite build-up: (i) the relative specific growth rates of nitrosomonas to nitrobacter, microns/micronb in the biofilm; (ii) the relative initial ratio between nitrosomonas and nitrobacter on the support surface, (mao)ns/(mao)nb; (iii) the level of free ammonia, particularly at greater than 0.1 mg n/l that can be inhibitory to ni ...200111501303
activity monitoring for nitrifying bacteria by fluorescence in situ hybridization and respirometry.the activities of two families of nitrifying bacteria were measured by applied respirometer and fluorescence in situ hybridization (fish) for the purpose of monitoring nitrogen removal. oxygen uptake rates (our) for nitrosomonas and nitrobacter were separately measured with the dosing of selective inhibitors during respirometric monitoring. the fish method was applied to analyze microorganism communities. in 5 mg nh4+-n/l solution, the total nitrogen oxygen demand (nod) was found to be 6,672 mg ...200111516017
a bioreactor system for the nitrogen loop in a controlled ecological life support space missions become longer in duration, the need to recycle waste into useful compounds rises dramatically. this problem can be addressed by the development of controlled ecological life support systems (celss) (i.e., engineered closed/controlled eco-systems (ecces)), consisting of human and plant modules. one of the waste streams leaving the human module is urine. in addition to the reclamation of water from urine, recovery of the nitrogen is important because it is an essential nutrien ...199611538973
the phylogeny of purple bacteria: the alpha subdivision.the technique of oligonucleotide cataloging shows the purple photosynthetic eubacteria to comprise three major subdivisions, temporarily called alpha, beta, and gamma--previously designated groups i-iii by gibson et al. (1979). each subdivision contains a number of non-photosynthetic genera in addition to the photosynthetic ones. the alpha subdivision, the subject of the present report, contains most but not all of the species that fall into the classically defined genera rhodospirillum, rhodo ...198411541974
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