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
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 ...200312713462
changing concepts in the systematics of bacterial nitrogen-fixing legume of february 2003, bacteria that form nitrogen-fixing symbiotic associations with legumes have been confirmed in 44 species of 12 genera. phylogenies of these taxa containing legume symbionts based on the comparative analysis of 16s rdna sequences show that they are not clustered in one lineage but are distributed in the classes alphaproteobacteria and betaproteobacteria, and dispersed over the following nine monophyletic groups, being intermingled with other taxa that do not contain legume sy ...200312949698
minimum phosphate and magnesium requirements of nitrifying bacteria. 195213013339
[the relation of oxidized nitrogen to the reduced carbon in nitrobacter]. 195413171874
[on nitrite oxidation by nitrobacter winogradskyi]. 195413229327
[physiology and biochemistry of nitrifying micro-organisms]. 195613321534
[nitrite oxidation by nitrobacter vinogradskii buch. and its relation to weather factors]. 195613340834
ferrobacillus ferrooxidans: a chemosynthetic autotrophic bacterium. 195613376518
the biochemistry of the nitrifying organisms. v. nitrite oxidation by nitrobacter. 195713403908
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
cytochromes of nitrobacter. 195813590096
cell-free nitrification by nitrobacter. 195813598710
[agents initiating the second phase of nitrification. ii. effect of heavy metals on nitrification]. 195813622243
[organism inducing the second phase of nitrification. iii. morphology of the organism inducing the second phase of nitrification]. 195813632414
nitrite oxidation by nitrobacter in the presence of certain nitrophenols. 196013689460
the biochemistry of the nitrifying organisms. 6. the effect of oxygen concentration on nitrite oxidation in the presence of different inorganic ions. 196013689461
the biochemistry of the nitrifying organisms. 7. the phosphate compounds of nitrobacter and the uptake of orthophosphate by the organism. 196013689462
[the assimilation of carbon dioxide by nitrobacter winogradskyi]. 196113755762
[photoinactivation of nitrobacter winogradskyi buch]. 196113773574
on the excitant of the 2nd phase of nitrification. iv. dehydrogenase activity of the washed suspension of nitrobacter winogradsky buch 196013788009
nutrition and physiology of nitrobacter agilis. 196013792492
the isolation and culture of the nitrifying organisms. part i. nitrobacter. 196013828576
[on the effect of hydrocyanic acid on chemical synthesis]. 196113830946
[research on chemical synthesis]. 196113830947
the morphology of nitrobacter winogradskyi. 195913847099
[the gross equation of carbon dioxide-assimilation of nitrobacter winogradskyi buch]. 195913849711
use of electron paramagnetic resonance spectroscopy in investigations of functional metal components in micro-organisms. 196213938326
kinetics of nitrite oxidation by nitrobacter winogradskyi. 196214013807
[on the mechanism of chemosynthesis]. 196214037073
[on the mechanism of chemosynthesis. on the "residual respiration" of chemoautotrophic nitrobacter winogradskyi]. 196314042164
[bacterial associations and biological alterations of limestone monuments]. 196314048726
adenosine triphosphate-dependent reduction of nicotinamide adenine dinucleotide by ferro-cytochrome c in chemoautotrophic bacteria. 196314087009
[on the reduction of diphosphopyridine nucleotide in chemo-synthesis]. 196314087312
[the behavior of nitrobacter winogradskyi buch. towards increased co2 partial pressure]. 196414134892
[apropos of nitrate reductases of a denitrifying bacterium]. 196414205501
on the assimilation of energy from inorganic sources in autotrophic forms of life. 196414224403
the biochemistry of the nitrifying organisms. 8. the effects of oxygen tension, nitrite concentration, and cyanate concentration on nitrite oxidation by nitrobacter. 196414228219
[the behavior of nitrifying bacteria towards dissolved oxygen]. 196414245150
molybdenum as a micronutrient for nitrobacter.finstein, m. s. (university of california, davis), and c. c. delwiche. molybdenum as a micronutrient for nitrobacter. j. bacteriol. 89:123-128. 1965.-the requirement of nitrobacter for molybdenum was investigated by use of a medium purified by chemical means, as well as by depletion by the prior growth of this autotrophic bacterium. during 5 days of growth, added molybdenum induced an approximately 11-fold increase in both nitrite utilization and cell-mass development. in short-term studies, max ...196514255651
characterization of a nitrate reductase from the chemoautotroph nitrobacter agilis. 196514284757
determination of kinetic constants for nitrifying bacteria in mixed culture, with the aid of an electronic computer. 196514287204
structure of nitrosocystis oceanus and comparison with nitrosomonas and nitrobacter.murray, r. g. e. (university of western ontario, london, ont., canada), and s. w. watson. structure of nitrosocystis oceanus and comparison with nitrosomonas and nitrobacter. j. bacteriol. 89:1594-1609. 1965.-nitrosocystis oceanus has distinctive features: the cell wall (overall thickness, 250 a) has an inner triplet structure and a dense enveloping layer; between these lie the "cell-wall organelles" (two or more per cell; plaques about 0.5 mu in diameter and 0.1 mu thick) of unknown function an ...196514293026
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
go or no go for gel entrapped nitrifiers? a belgian case the coming years, as stricter environmental requirements are imposed, many european union wastewater treatment plants (wwtp) need to be expanded and/or upgraded. this requires considerable investments. optimising the renovation recourses can lead to significant savings. the use of entrapped nitrifying bacteria for upgrading of wwtp towards nutrient removal may be benificial. long term pilot tests were performed to evaluate a so-called pellet reactor. differences in performance and microbiolog ...200212216669
melissa: a loop of interconnected bioreactors to develop life support in space.the development of a loop of interconnected continuous bioreactors, aimed to provide life support in space, is reported. the complete loop concept consists of four bioreactors and one higher plant compartment. for its realization the continuous and controlled operation of the bioreactors is characterized, up to the pilot scale level, first for each individual reactor, second for the interconnected reactor operation. the results obtained with the two more advanced bioreactors in the micro ecologi ...200212385718
diversity of nitrifying bacteria in full-scale chloraminated distribution systems.chloramination for secondary disinfection of drinking water often promotes the growth of nitrifying bacteria in the distribution system due to the ammonia introduced by chloramine formation and decay. this study involved the application of molecular biology techniques to explore the types of ammonia-oxidizing bacteria (aob) and nitrite-oxidizing bacteria (nob) present in several full-scale chloraminated systems. the results of aob community characterization indicated the ubiquitous detection of ...200312465801
[vfeu water quality control in sts-95 aquatic animal experiment]. 199912533005
canon and anammox in a gas-lift reactor.anoxic ammonium oxidation (anammox) and completely autotrophic nitrogen removal over nitrite (canon) are new and promising microbial processes to remove ammonia from wastewaters characterized by a low content of organic materials. these two processes were investigated on their feasibility and performance in a gas-lift reactor. the anammox as well as the canon process could be maintained easily in a gas-lift reactor, and very high n-conversion rates were achieved. an n-removal rate of 8.9 kg n (m ...200312586414
use of polyclonal antibodies to detect and quantify the nor protein of nitrite oxidizers in complex the approaches or models which aim to understand and/or predict how the functioning of ecosystems may be affected by perturbations or disturbances, little attention is generally given to microorganisms. even when they are taken into account as indicators, variables which are poorly informative about the changes in the microbial functioning (microbial biomass or diversity or total number of microorganisms) are often used. to be able to estimate, in complex environments, the quantity of enzymes ...200312609727
biological treatment process of air loaded with an ammonia and hydrogen sulfide mixture.the physico-chemical characteristics of granulated sludge lead us to develop its use as a packing material in air biofiltration. then, the aim of this study is to investigate the potential of unit systems packed with this support in terms of ammonia and hydrogen sulfide emissions treatment. two laboratory scale pilot biofilters were used. a volumetric load of 680 g h2s m(-3) empty bed day(-1) and 85 g nh3 m(-3) empty bed day(-1) was applied for eight weeks to a unit called bgsn (column packed wi ...200312656240
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 ...200312710742
[problem of nitrite oxidation with supplementary co2 assimilation in nitrobacter winogradskii buch]. 195713522131
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
vfeu water quality control in sts-95 sts-95 space shuttle mission, an aquatic animal research facility, vestibular function experiment unit (vfeu), was flown to perform neurobiological experiment with marine fish, oyster toadfish. for this purpose, we have developed a sea water purification system using highly active nitrifying bacteria at low temperature. with this system, the water quality in the vfeu was maintained in sufficient condition to keep the toadfish in healthy state for 9 days of the mission. this report summarizes ...199911542797
potential nitrification rate as a tool for screening toxicity in metal-contaminated soils.a potential nitrification rate test (pnr) was used to identify metal toxicity in field-contaminated soils. the test was applied to metal salt-spiked soils, to 27 uncontaminated soils, and to 15 soils that are contaminated by former metal smelting activities. four agricultural soils (ph 4.5-6.6) were spiked with various rates of cdcl2 (0-200 mg cd/kg dry wt) or zncl2 (0-3,000 mg cd/kg dry wt) and were equilibrated more than nine months prior to testing. the soil zn ec50s of the pnr were between 1 ...200111699771
ammonia- and nitrite-oxidizing bacterial communities in a pilot-scale chloraminated drinking water distribution system.nitrification in drinking water distribution systems is a common operational problem for many utilities that use chloramines for secondary disinfection. the diversity of ammonia-oxidizing bacteria (aob) and nitrite-oxidizing bacteria (nob) in the distribution systems of a pilot-scale chloraminated drinking water treatment system was characterized using terminal restriction fragment length polymorphism (t-rflp) analysis and 16s rrna gene (ribosomal dna [rdna]) cloning and sequencing. for ammonia ...200211772611
fatty acid profiles of nitrite-oxidizing bacteria reflect their phylogenetic heterogeneity.the fatty acid profiles of all described species of the nitrite-oxidizing genera nitrobacter, nitrococcus, nitrospina and nitrospira were analyzed. the four genera had distinct profiles, which can be used for the differentiation and allocation of new isolates to these genera. the genus nitrobacter is characterized by vaccenic acid as the main compound with up to 92% of the fatty acids and the absence of hydroxy fatty acids. the genus nitrococcus showed cis-9-hexadecenoic acid, hexadecanoic acid ...200111822673
water purification system by using the biofilter for long-term experiment equipment with aquatic animals for the space station.we have developed a water purification system that enables long-term experiment with aquatic animals for 90 days or more on the space station. we designed the system that combined a biofilter for ammonia removal (nitrification) with another for nitrate removal (denitrification). the experiment with goldfish was for 90 days with an aquatic animals' examination device. the equipment consists of a fish tank, a filter module, pumps, and an artificial lung for gas exchange. the goldfish were kept in ...199811876203
the canon system (completely autotrophic nitrogen-removal over nitrite) under ammonium limitation: interaction and competition between three groups of bacteria.the canon system (completely autotrophic nitrogen removal over nitrite) can potentially remove ammonium from wastewater in a single, oxygen-limited treatment step. the usefulness of canon as an industrial process will be determined by the ability of the system to recover from major disturbances in feed composition. the canon process relies on the stable interaction between only two bacterial populations: nitrosomonas-like aerobic and planctomycete-like anaerobic ammonium oxidising bacteria. the ...200111876366
immunological detection of nitrospira-like bacteria in various soils.chemolithotrophic nitrite oxidizers were enriched from five different soils including freshwater marsh, permafrost, garden, agricultural, and desert soils and monitored during the cultivation procedure. immunoblot analysis was used to identify the nitrite oxidizing organisms with monoclonal antibodies, which recognize the key enzyme of nitrite oxidation in a genus-specific reaction [bartosch et al. (1999) appl environ microbiol 65:4126-4133]. the morphological characteristics of the enriched nit ...200211984626
intestinal urea metabolism: could the bacteria involved in nitrogen cycle lead to reutilization of intestinal urea nitrogen in uremic rabbits?we aimed to evaluate the effect of bacteria involved in the nitrogen cycle on the reutilization of intestinal urea nitrogen in uremic rabbits. new zealand white rabbits were made uremic via bilateral nephrectomy. study and control rabbits were given live and heat-inactivated bacteria through their jejunostomies. after they were injected with 99mtc biurea intravenously, serial serum and stool levels of labeled nitrogen were assessed by instant thin-layer chromatography, and the change in the labe ...200212026184
high mortality in zebrafish (danio rerio).a group of 100 adult zebrafish were housed in a new system at a stocking density of 20 fish per tank. four weeks after arrival, 15 fish presented with petechial hemorrhages and ulceration on the surfaces of the skin. samples of the fish were collected for histopathology, fungal culture, and bacterial culture and sensitivity. water samples were analyzed for ph, ammonia, nitrite, and submitted for bacterial and fungal culture. histologically, the epidermis had multiple areas of ulceration and mono ...199912086431
tfda-like genes in 2,4-dichlorophenoxyacetic acid-degrading bacteria belonging to the bradyrhizobium-agromonas-nitrobacter-afipia cluster in alpha-proteobacteria.the 2,4-dichlorophenoxyacetate (2,4-d)/alpha-ketoglutarate dioxygenase gene (tfda) homolog designated tfdaalpha was cloned and characterized from 2,4-d-degrading bacterial strain rd5-c2. this japanese upland soil isolate belongs to the bradyrhizobium-agromonas-nitrobacter-afipia cluster in the alpha subdivision of the class proteobacteria on the basis of its 16s ribosomal dna sequence. sequence analysis showed 56 to 60% identity of tfdaalpha to representative tfda genes. a male-tfdaalpha fusion ...200212089027
use of natural zeolite to enhance nitrification in enhance nitrification, natural zeolite and activated carbon were tested as a media in a biofilter to treat wastewater containing relatively high concentrations of tkn. using those media, the adsorption isotherms for ammonium ion were compared; the k values for natural zeolite and activated carbon were found to be 0.5117 and 0.0006, respectively. in comparison of the performance of the two media, two identical, lab-scale biofilters were then operated for 4 months. the effect of nh3-n loading r ...200212164639
[studies on the respiration of nitrobacter winogradskyi buch]. 196514304663
the effect of 2-chloro, 6-(trichloromethyl) pyridine on the chemoautotrophic metabolism of nitrifying bacteria. ii. nitrite oxidation by nitrobacter. 196514315632
[studies on the influence of temperature on nitrification in the elbe estuary]. 196414320216
poly-beta-hydroxybutyric acid in nitrobacter. 196514323606
continuous flow method in soil microbiology. v. nitrification. 196514332135
[comparative studies on the effect of visible light on nitrosomonas europaea and nitrobacter winogradskyi]. 196514347921
the effect of chlorate on the rate of nitrite oxidation by nitrobacter. 195414351163
the use of cyanate and chlorate in studies on the relation between the nitrite oxidation and the reduction of a cytochrome system in nitrobacter. 195414351219
kinetics of the nitrite oxidation by nitrobacter winogradskyi. 196014414502
bacterial destruction of sodium nitrite in open cooling water systems. 195914418926
[the inactivation of the oxidation capacity of nitrobacter winogradskyi buch]. 195914444497
formate odixation by cell-free preparations from nitrobacter agilis. 196214468824
the effect of 2,3,6-trichlorophenylacetic and 2,2-dichloropropionic acids on nitrite oxidation.the effects of two herbicides, 2,3,6-trichlorophenylacetic acid, sodium salt, and 2,2-dichloropropionic acid, sodium salt, on nitrite-oxidizing bacteria were studied by the soil perfusion technique. the time of application of 2,3,6-trichlorophenylacetic acid affected its toxicity to the nitrifier. when it was present in the environment as the nitrifier started growth, it was more toxic than if the organisms were allowed to nitrify actively before they were subjected to the herbicide. the herbici ...196214471731
growth rates of nitrifying chemoautotrophs in soil. 196214476222
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 ...200314509699
treatment of nitrogen and phosphorus in highly concentrated effluent in sbr and sbbr processes.various sludge treatment processes produced supernatant with high ammonia concentration from 500 to 2,000 mgn/l and generally high phosphate concentration. conversion of ammonia into nitrite via partial nitrification has proven to be an economic way, reducing oxygen and external cod requirements during the nitrification/denitrification process. two processes with biomass retention are studied simultaneously: the sequencing batch reactor (sbr) and the sequencing batch biofilm reactor (sbbr). at a ...200415537016
[potential of nitrification and denitrification in water purification system with hydroponic bio-filter method].the potential of nitrification and denitrification of sediment and the density of ammonium-oxidizing bacteria and nitrite-oxidizing bacteria in sediment in water quality purifying system with hydroponic bio-filter method (hbfm) were measured. the variation of nitrification and denitrification potential of the sediment along the stream way was quantitatively studied. the results show that among the sediments from front, middle and retral part of the stream way, the sediment from middle part reach ...200516004307
dna microarray detection of nitrifying bacterial 16s rrna in wastewater treatment plant samples.a small scale dna microarray containing a set of oligonucleotide probes targeting the 16s rrnas of several groups of nitrifying bacteria was developed for the monitoring of wastewater treatment plant samples. the microarray was tested using reference rrnas from pure cultures of nitrifying bacteria. characterization of samples collected from an industrial wastewater treatment facility demonstrated that nitrifying bacteria could be detected directly by microarray hybridization without the need for ...200516009395
para-chlorophenol inhibition on cod, nitrogen and phosphate removal from synthetic wastewater in a sequencing batch reactor.cod, nitrogen, phosphate and para-chlorophenol (4-chlorophenol, 4-cp) removal from synthetic wastewater was investigated using a four-step sequencing batch reactor (sbr) at different sludge ages and initial para-chlorophenol (4-cp) concentrations. the nutrient removal process consisted of anaerobic, oxic, anoxic and oxic phases with hydraulic residence times (hrt) of 1/3/1/1 h and a settling phase of 0.75 h. a box-wilson statistical experiment design was used considering the sludge age (5-25 day ...200516023572
nitrification performance and microbial community dynamics in a submerged membrane bioreactor with complete sludge retention.a submerged membrane bioreactor (mbr) supplied with inorganic ammonium-bearing wastewater (nh(4)(+)-n, 500 mgl(-1)) was operated for 260 days without sludge purge under decreased hydraulic retention times (hrt) through six steps (from 30 to 5h). almost complete nitrification was obtained at a volumetric loading rate (vlr)1.2g nh(4)(+)-nl(-1)day(-1). the sludge nitrification activities were evaluated at each stage. the specific ammonium oxidizing rate (saor) decreased from the initial 0.45 to 0.1 ...200616310272
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 ...200516332337
influence of inorganic nitrogen management regime on the diversity of nitrite-oxidizing bacteria in agricultural grassland assess links between the diversity of nitrite-oxidizing bacteria (nob) in agricultural grassland soils and inorganic n fertilizer management, nob communities in fertilized and unfertilized soils were characterized by analysis of clone libraries and denaturing gradient gel electrophoresis (dgge) of 16s rrna gene fragments. previously uncharacterized nitrospira-like sequences were isolated from both long-term-fertilized and unfertilized soils, but dgge migration patterns indicated the presence ...200516332819
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 ...200516332848
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 ...198016345632
serological diversity of nitrobacter spp. from soil and aquatic habitats.serotypic diversity among nitrobacter spp. isolates is greater than previously reported. typing with fluorescent antibodies prepared against 11 nitrobacter spp. cultures isolated from soil and water placed the isolates into six serogroups. when these fluorescent antibodies were applied to a group of 16 additional isolates, 8 were identifiable by cross-reaction to 3 of the 11 fluorescent antibodies. some nitrite-oxidizing enrichment cultures from different habitats contained cross-reacting strain ...198116345749
inhibitor evaluation with immobilized nitrobacter agilis cells.nitrobacter agilis was entrapped in calcium alginate beads and used as a floating bed supplied with a continuous flow of nitrite medium. complete nitrite oxidation was achieved within 30 h, and the system could be maintained for at least 210 h. the immobilized nitrobacter system was subjected to sulfur oxyanions, acidity, and metal ions. thiosulfate and tetrathionate (up to 20 mm each) did not inhibit the nitrite oxidation activity. a low ph of 4.2 resulted in the complete cessation of nitrite o ...198616347230
chemolithotrophic haloalkaliphiles from soda lakes.this paper summarizes recent data on the occurrence and properties of lithotrophic prokaryotes found in extremely alkaline, saline (soda) lakes. among the chemolithotrophs found in these lakes the obligately autotrophic sulfur-oxidizing bacteria were the dominant, most diverse group, best adapted to haloalkaline conditions. the culturable forms are represented by three new genera, thioalkalimicrobium, thioalkalivibrio and thioalkalispira in the gammaproteobacteria. among them, the genus thioalka ...200516329914
research on leachate recirculation from different types of landfills.landfills can produce a great amount of leachate containing highly concentrated organic matter. this is especially true for the initial leachate from landfilled municipal solid wastes (msw) that generally has concentrations of cod(cr) and bod(5) up to 80,000 and 50,000mg/l, respectively. the leachate could be disposed by means of recirculating technique, which decomposes the organics through the action of proliferating microorganisms and thereby purifies the leachate, and simultaneously accelera ...200616321514
nitrobacter and nitrospira genera as representatives of nitrite-oxidizing bacteria: detection, quantification and growth along the lower seine river (france).pollution from agriculture and urban effluents influences the ecology and biochemical functioning of the seine river. nitrification dominates nitrogen transformations downstream of the effluents of the paris wastewater treatment plant (wwtp) at achères, treating, by activated sludge the wastewater of 6.5 million inhabitant equivalents from paris and its suburbs, without nitrification and denitrification treatment. it discharges effluents containing large amounts of nitrogen, ammonium mostly (app ...200516303163
improvement of nano2-oxidizing activity in nitrobacter vulgaris by coentrapment in polyacrylamide containing polydimethylsiloxane copolymer and deae-sephadex.removal of nitrite and nitrate from drinking water has attracted great attention in recent years because of the human health risk induced by the exposure to contaminated groundwater and surface water. we have therefore tested a model nitrite oxidation system by coentrapping the nano2 oxidizer nitrobacter vulgaris with polydimethylsiloxane (pdms) copolymer and deae-sephadex in a polyacrylamide gel. the copolymer and the anion exchanger facilitate the diffusion of oxygen and nano2, respectively, i ...200516204501
quantitative determination of the spatial distribution of nitrosomonas europaea and nitrobacter agilis cells immobilized in kappa-carrageenan gel beads by a specific fluorescent-antibody labelling technique.a novel technique, combining labelling and stereological methods, for the determination of spatial distribution of two microorganisms in a biofilm is presented. cells of nitrosomonas europaea (atcc 19718) and nitrobacter agilis (atcc 14123) were homogeneously distributed in a kappa-carrageenan gel during immobilization and allowed to grow out to colonies. the gel beads were sliced in thin cross sections after fixation and embedding. a two-step labelling method resulted in green fluorescent colon ...199316348970
effects of grazing by flagellates on competition for ammonium between nitrifying and heterotrophic bacteria in soil columns.the enhanced mineralization of immobilized nitrogen by bacteriophagous protozoa has been thought to favor the nitrification process in soils in which nitrifying bacteria must compete with heterotrophic bacteria for the available ammonium. to obtain more insight into this process, the influence of grazing by the flagellate adriamonas peritocrescens on the competition for ammonium between the chemolithotrophic species nitrosomonas europaea and the heterotrophic species arthrobacter globiformis in ...199316348988
selective inhibition of ammonium oxidation and nitrification-linked n(2)o formation by methyl fluoride and dimethyl ether.methyl fluoride (ch(3)f) and dimethyl ether (dme) inhibited nitrification in washed-cell suspensions of nitrosomonas europaea and in a variety of oxygenated soils and sediments. headspace additions of ch(3)f (10% [vol/vol]) and dme (25% [vol/vol]) fully inhibited no(2) and n(2)o production from nh(4) in incubations of n. europaea, while lower concentrations of these gases resulted in partial inhibition. oxidation of hydroxylamine (nh(2)oh) by n. europaea and oxidation of no(2) by a nitrobacter s ...199316349011
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