| the influence of some herbicides on selected groups of microorganisms in loess and sandy soils. ii. the effect of nitrification. | studies on the effect of herbicides on nitrification in field and laboratory conditions have shown that steady use of these substances in the same field does not exert a significant effect on this process in the soil. the herbicides caused only shortlasting disturbances. nitrification usually returned to a relative equilibrium in several days after the herbicide application. | 1977 | 67749 |
| polyhedral inclusion bodies in cells of nitrosomonas spec. | polyhedral inclusion bodies were observed in cells of a nitrosomonas species. they were present in growing cells as well as in resting cells. in thin sections their size was about 130 nm in growing cells and about 185 nm in diameter in resting cells. the bodies were commonly located in the nucleoplasm. they appeared to be bounded by a nonunit membrane and had a granular substructure. in thin sections about 70% of the exponentially grown cells and about 20% of the resting cells of the investigate ... | 1977 | 190964 |
| hydroxylamine oxidoreductase of nitrosomonas. oxidation of diethyldithiocarbamate concomitant with stimulation of nitrite synthesis. | | 1977 | 199251 |
| purification and some properties of cytochrome c-552 from an extreme thermophile, thermus thermophilus hb8. | a c-type cytochrome, cytochrome c-552, from a soluble fraction of an extreme thermophile, thermus thermophilus hb8, was highly purified and its properties investigated. the absorption peaks were at 552, 522, and 417 nm in the reduced form, and at 408 nm in the oxidized form. the isoelectric point was at ph 10.8, the midpoint redox potential was about +0.23 v, and the molecular weight was about 15,000. the cytochrome c-552 was highly thermoresistant. the cytochrome reacted rapidly with pseudomona ... | 1977 | 199583 |
| nitrification in histosols: a potential role for the heterotrophic nitrifier. | insufficient populations of nitrosomonas and nitrobacter were found in a pahokee muck soil (lithic medidaprit) to account for the nitrate concentration observed. to determine if heterotrophic nitrifiers could account for some of this discrepancy, a method was developed to measure the levels of heterotrophic nitrifiers in soil. a population of 4.1 x 10(5) arthrobacter per g of dry fallow soil, capable of producing nitrite and/or nitrate from reduced nitrogenous compounds, was observed. amendment ... | 1977 | 869537 |
| an automated biological nitrification toxicity test. | | 1976 | 994305 |
| competitive inhibition of ammonia oxidation in nitrosomonas europaea by methane, carbon monoxide or methanol. | | 1976 | 1001454 |
| crystallization and preliminary x-ray studies of hydroxylamine oxidoreductase from nitrosomonas europaea. | hydroxylamine oxidoreductase [ec 1.7.3.4] from nitrosomonas europaea was crystallized by the microdialysis method using ammonium sulfate. its space group is p63 with cell dimensions of a = b = 96.4 a and c = 266.2 a. its molecular weight was determined to be 190,000-195,000 by the x-ray small angle scattering and ultracentrifugal methods. | 1991 | 1783597 |
| protection of nitrosomonas europaea colonizing clay minerals from inhibition by nitrapyrin. | nitrate production by nitrosomonas europaea in inorganic liquid medium containing ammonium was limited by reduction in ph. in the presence of montmorillonite and vermiculite, expanding clays with high cation-exchange-capacity (cec), nitrite yield was increased, ammonia oxidation continued at ph values below those which inhibited growth in the absence of clays and growth was biphasic. the first phase was similar to that in the absence of clays, while the second was characterized by a lower rate o ... | 1991 | 1955871 |
| quantitative structure-activity relationships for chemical toxicity to environmental bacteria. | quantitative structure-activity relationships (qsars) were developed for nonreactive chemical toxicity to each of four groups of bacteria of importance in environmental engineering: aerobic heterotrophs, methanogens, nitrosomonas, and microtox. the qsars were based on chemicals covering a range of structures and including important environmental pollutants (i.e., chlorinated and other substituted benzenes, phenols, and aliphatic hydrocarbons). qsars were developed for each chemical class and for ... | 1991 | 1769352 |
| 14c2h2- and 14co2-labeling studies of the de novo synthesis of polypeptides by nitrosomonas europaea during recovery from acetylene and light inactivation of ammonia monooxygenase. | incubation of cells of the nitrifying bacterium nitrosomonas europaea with 14c2h2 results in the covalent attachment of 14c label to a membrane-bound polypeptide of an approximate mr of 28,000 (hyman, m.r., and wood, p.m. (1985) biochem. j. 227, 719-725). a labeling procedure using 14c2h2 generated from ba14co3 has been used to investigate the correlation between the extent of covalent modification of this polypeptide by 14c from 14c2h2 and the level of ammonia oxidizing activity in whole cells. ... | 1992 | 1730700 |
| spectroscopic and rapid kinetic studies of reduction of cytochrome c554 by hydroxylamine oxidoreductase from nitrosomonas europaea. | during oxidation of hydroxylamine, hydroxylamine oxidoreductase (hao) transfers two electrons to tetraheme cytochrome c554 at rates sufficient to account for physiological rates of oxidation of ammonia to nitrite in nitrosomonas europaea. spectroscopic changes indicate that the two electrons are taken up by a high-potential pair of hemes (e degrees' = +47 mv) (one apparently high spin and one low spin). during single-turnover experiments, in which the reduction of oxidized cytochrome c554 by nh2 ... | 1991 | 1660304 |
| resolution of the four hemes of cytochrome c554 from nitrosomonas europaea by redox potentiometry and optical spectroscopy. | the electrochemical behavior of tetraheme cytochrome c554 from nitrosomonas europaea has been studied by thin-layer spectroelectrochemistry, cyclic voltammetry, differential pulse voltammetry, and alternating current voltammetry. three redox couples were detected. midpoint potentials for the high-m intermediate-, and low-potential couples are +47, -147, and -276 mv, respectively, from the spectroelectrochemical measurements and +50, -120, and -225 mv, respectively, from the voltammetry measureme ... | 1991 | 1660303 |
| c-cytochromes of the ammonia-oxidizing chemolithoautotrophic bacteria. | | 1991 | 1646009 |
| acceleration of the oxygen reaction in cua-deficient nitrosomonas europaea cytochrome c oxidase as revealed by the flow-flash measurement. | the oxygen reaction of nitrosomonas europaea cytochrome c oxidase containing either 2cu or 1cu per two heme a molecules was investigated by the flow-flash technique at 20 degrees c. the reaction profiles of the bacterial enzyme were essentially the same as those of bovine heart cytochrome c oxidase, although the rate of the primary oxygen compound formation was much slower. the 1cu enzyme exhibited higher rates for both primary oxygen compound formation and intramolecular electron transfer than ... | 1992 | 1311570 |
| 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 |
| [thermophilic nitrifying bacteria from hot springs]. | a culture of thermophilic nitrifying bacteria was isolated from geothermal springs of kamchatka (50-86 degrees c, ph 6.3-7.5) and tajig ssr (50-85 degrees c, ph 7.3-8.5). the culture oxidizes ammonium nitrogen at 40-70 degrees c. it resembles nitrosomonas europea winogradskyi by its morphology. dimensions of the cells vary within 0.7-0.9 x 0.8-1.4 mcm. each cell has a polar flagellum whose diameter is about 140 a. this is the first description of thermophilic nitrifying bacteria belonging to the ... | 1976 | 933875 |
| catalytic properties of cytochrome c oxidase purified from nitrosomonas europaea. | cytochrome c oxidase of nitrosomonas europaea reacts with not only the native cytochrome c (n. europaea cytochrome c-552) but also horse and yeast cytochromes c. the effects on its reactivity of various reagents were very different between the reactions with the native and eukaryotic cytochromes c as the electron donors. the oxidation of eukaryotic ferrocytochrome c by the oxidase was activated by addition of anionic detergents such as sodium dodecyl sulfate and sodium cholate, and anionic phosp ... | 1988 | 2839468 |
| nitrification in the intertidal zone: influence of effluent type and effect of tannin on nitrifiers. | nitrification by intertidal sediments was measured by using a tide simulator that approximated the cycle of seawater on tidal flats. sediments were chosen from sites affected by industrial and municipal effluents and pastoral seepage and runoff. the ability of sediments from different sites to nitrify endogenous nitrogen varied markedly. all sites exhibited an initial lag before activity commenced. the duration of this lag and the rate of nitrate production were different at each site. the sedim ... | 1977 | 931375 |
| hydroxylamine oxidoreductase from nitrosomonas: inactivation by hydrogen peroxide. | incubation of hydroxylamine oxidoreductase of nitrosomonas with hydrogen peroxide resulted in the rapid and irreversible loss of the ability to catalyze the dehydrogenation of hydroxylamine in the presence of electron acceptors, such as phenazine methosulfate. the rate of the reaction was dependent on the concentration of enzyme and h2o2. inactivation occurred most rapidly at ph values between 9 and 10. inactivation of the enzyme by h2o2 did not result in alteration of absorption spectrum of eit ... | 1977 | 836796 |
| [comparative biochemistry of dissimilatory nitrite reductases (author's transl)]. | | 1976 | 818322 |
| purification of electron-transfer components of nitrifying and denitrifying bacteria and assay of intermediates. | | 1978 | 713858 |
| hydroxylamine oxidoreductase from nitrosomonas: absorption spectra and content of heme and metal. | | 1978 | 698180 |
| conformational change accompanies redox reactions of the tetraheme cytochrome c-554 of nitrosomonas europaea. | cytochrome c-554 of the ammonia-oxidizing chemolithoautotropic bacteria is thought to mediate electron transfer from hydroxylamine oxidoreductase to a terminal oxidase and/or to ammonia monooxygenase. the cytochrome has four c hemes which interact magnetically and have the same redox potential. we report that the kinetics of reduction of ferric cytochrome c-554 by dithionite or the oxidation of ferrous cytochrome c-554 by o2 or h2o2 are complex and multiphasic. transient rapid-scan difference sp ... | 1987 | 3026805 |
| [biology of chemoautotrophs]. | | 1988 | 3150584 |
| stable isotope studies on the oxidation of ammonia to hydroxylamine by nitrosomonas europaea. | | 1979 | 499527 |
| hydroxylamine oxidoreductase of nitrosomonas. production of nitric oxide from hydroxylamine. | | 1979 | 497235 |
| effect of benomyl and its hydrolysis products, mbc and ab, on nitrification in a flooded soil. | | 1979 | 444723 |
| highly purified hydroxylamine oxidoreductase derived from nitrosomonas europaea. some physicochemical and enzymatic properties. | hydroxylamine oxidoreductase [ec 1.7.3.4] of nitrosomonas europaea was purified to an electrophoretically homogeneous state and some of its properties were studied. the molecular weight of the enzyme as determined by gel filtration on sephadex g150 and by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate is 175,000-180,000, while the minimum molecular weight per heme determined from the dry weight and heme content is 17,500. the enzyme is a c-type cytochrome; its reduc ... | 1979 | 227845 |
| a comparison between nitrosomas europaea and thiobacillus novellus on the basis of their oxidation systems of inorganic compounds. | nitrosomonas europaea and thiobacillus novellus were compared with each other on the basis of the biochemical properties of their inorganic compound-oxidizing systems. cytochromes c of the two organisms differ considerably from each other; n. europaea cytochrome c-552 belongs to the "bacterial-type" cytochrome c, while t. nouellus cytochrome c-550 resembles eucaryolic cytochrome c. the specificity of cytochrome oxidase for cytochrome c as the electron donor is different between the two organism ... | 1977 | 198039 |
| [studies on some unusual c type cytochromes (author's transl)]. | | 1977 | 193149 |
| mechanisms of inorganic oxidation and energy coupling. | | 1974 | 4215368 |
| [oxidation of inorganic compound by autotrophic bacteria (author's transl)]. | | 1976 | 184217 |
| the metabolism of hydroxylamine to nitrite by nitrosomonas. | | 1964 | 4284178 |
| [effect of fertilizers on the number of bacteria involved in the turnover of nitrogen in pond water of the astrakhan region]. | the type of intensification affects the distribution of bacteria involved in turnover of nitrogen in pond water. green fertilizers (reed) stimulate the number of nitrogen-fixing bacteria, and the number and activity of nitrifying bacteria, to a higher degree than nitrogen and phosphorus fertilizers. reed is recommended as the main means for intensification of spawning ponds of the astrakhan region. | 1976 | 137355 |
| biochemical basis of obligate autotrophy in nitrosomonas europaea. | the specific activities of isocitric dehydrogenase, alpha-ketoglutaric dehydrogenase, succinic dehydrogenase, malic dehydrogenase, and reduced nicotinamide adenine dinucleotide (nadh) oxidase were determined in extracts of nitrosomonas europaea and compared with the corresponding values for anacystis nidulans and autotrophically grown hydrogenomonas eutropha. in common with other obligate autotrophs and in contrast to facultative autotrophs, nitrosomonas extracts lacked alpha-ketoglutaric dehydr ... | 1969 | 4304222 |
| [isolation and properties of nitrosomonas europaea cytochrome c]. | | 1967 | 4305222 |
| energy coupling and respiration in nitrosomonas europaea. | intact cells of nitrosomonas europaea grown in an ammonium salts medium will oxidise ammonium ions, hydroxylamine and ascorbate-tmpd; there is no oxidation of carbon monoxide, methane or methanol. the km value for ammonia oxidation is highly ph dependent with a minimum value of 0.5 mm above ph 8.0. this suggests that free ammonia is the species crossing the cytoplasmic membrane(s). the measurement of respiration driven proton translocation indicates that there is probably only one proton translo ... | 1976 | 13754 |
| the effect of ph and partial pressure of oxygen on nitrification (author's transl). | a mathematical model which describes the effect of ph and dissolved oxygen on growth and activity of nitrosomonas and nitrobacter in mixed culture is presented. a good fit is obtained between experimental data and theoretical curves computed with parameters estimated by independent methods. experimental data together with simulation studies show that inadequate aeration induces a temporal shift of ammonium and nitrite oxidations resulting in a transient nitrite accumulation similar to that cause ... | 1976 | 7988 |
| electron transport systems of nitrosomonas: isolation of a membrane-envelope fraction. | freezing and thawing of nitrosomonas, followed by centrifugation of the homogenate at 3,000 x g, resulted in a fraction which appeared to consist of an intact membrane-envelope complex and contained approximately 50% of the cell protein and more than 90% of the ubiquinone and cytochrome a-type mammalian cytochrome c oxidase activity. the supernatant fraction, resulting from subsequent centrifugation of the extract at 100,000 x g, contained approximately 50% of the cell protein and more than 80% ... | 1972 | 4336111 |
| cytochrome p-460 of nitrosomonas europaea: further purification and further characterization. | cytochrome p-460 of nitrosomonas europaea [erickson, r.h. and hooper, a.b. (1972) biochim. biophys. acta 275, 231-244] was further purified to an electrophoretically homogeneous state. the cytochrome molecule was composed of three molecules of subunits with mr of 17,300-18,500, and contained three atoms of iron, which seemed to be heme iron, and six cysteine residues, but did not contain nonheme iron or inorganic sulfide. the cytochrome showed absorption peaks at 460 and 688 nm with a broad shou ... | 1990 | 2089033 |
| p460 of hydroxylamine oxidoreductase of nitrosomonas europaea: soret resonance raman evidence for a novel heme-like structure. | p460, an iron-containing chromophore at the active site of hydroxylamine oxidoreductase of the ammonia-oxidizing bacterium nitrosomonas europaea, is a macrocycle of unknown structure with a soret-like 460-nm absorption band in the ferrous form. the pigment can also be isolated in a peptide, "p460-fragment". resonance raman spectroscopy (lambda ex = 457.9 nm) suggests that p460 is a new type of heme with symmetry properties lower than those of protophorphyrin ix or chlorins and similar to those o ... | 1991 | 1989613 |
| inhibition of ammonia monooxygenase in nitrosomonas europaea by carbon disulfide. | carbon disulfide has long been recognized as a potent inhibitor of nitrification, and it is the likely active component in several nitrification inhibitors suitable for field use. the effects of this compound on nitrosomonas europaea have been investigated, and the site of action has been determined. low concentrations of cs2 (less than 400 microm) produced a time-dependent inhibition of ammonia-dependent o2 uptake but did not inhibit hydrazine-oxidizing activity. cs2 also produced distinct chan ... | 1990 | 2118501 |
| purification of c-type cytochromes from nitrosomonas europaea. | | 1973 | 4352494 |
| photoinactivation of ammonia oxidation in nitrosomonas. | photoinactivation of ammonia oxidation in cells of nitrosomonas was shown to follow first-order kinetics with a rate constant proportional to incident light intensity. the action spectrum for photoinactivation consisted of a broad peak in the ultraviolet range, where both hydroxylamine and ammonia oxidation were affected, and a shoulder at approximately 410 nm where only ammonia oxidation was affected. in photoinactivated cells, hydroxylamine but not ammonia was oxidized to nitrite and hydroxyla ... | 1974 | 4369012 |
| cytochrome c-552 and cytochrome c-554 derived from nitrosomonas europaea. purification, properties, and their function in hydroxylamine oxidation. | | 1974 | 4372235 |
| eukaryotic cytochrome c-like properties of cytochrome c-550 (thiobacillus novellus). | | 1974 | 4373290 |
| generation of reducing power in chemosynthesis. ii. energy-linked reduction of pyridine nucleotides in the chemoautotroph, nitrosomonas europaea. | | 1966 | 4380274 |
| 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 |
| properties of some reductase enzymes in the nitrifying bacteria and their relationship to the oxidase systems. | the reductase enzymes in nitrosomonas and nitrobacter were studied under anaerobic conditions when the oxidase enzymes were inactive. the most effective electron-donor systems for nitrate reductase in nitrobacter were reduced benzyl viologen alone, phenazine methosulphate with either nadh or nadph, and fmn or fad with nadh. nitrite and hydroxylamine reductases were found in both nitrifying bacteria, and optimum activity for each enzyme was obtained with nadh or nadph with either fmn or fad. the ... | 1968 | 4386932 |
| ammonia-oxidizing bacteria in a chloraminated distribution system: seasonal occurrence, distribution and disinfection resistance. | nitrification in chloraminated drinking water can have a number of adverse effects on water quality, including a loss of total chlorine and ammonia-n and an increase in the concentration of heterotrophic plate count bacteria and nitrite. to understand how nitrification develops, a study was conducted to examine the factors that influence the occurrence of ammonia-oxidizing bacteria (aob) in a chloraminated distribution system. samples were collected over an 18-month period from a raw-water sourc ... | 1990 | 2306090 |
| degradation of halogenated aliphatic compounds by the ammonia- oxidizing bacterium nitrosomonas europaea. | suspensions of nitrosomonas europaea catalyzed the ammonia-stimulated aerobic transformation of the halogenated aliphatic compounds dichloromethane, dibromomethane, trichloromethane (chloroform), bromoethane, 1,2-dibromoethane (ethylene dibromide), 1,1,2-trichloroethane, 1,1,1-trichloroethane, monochloroethylene (vinyl chloride), gem-dichloroethylene, cis- and trans-dichloroethylene, cis-dibromoethylene, trichloroethylene, and 1,2,3-trichloropropane, tetrachloromethane (carbon tetrachloride), te ... | 1990 | 2339874 |
| oxidation of monohalogenated ethanes and n-chlorinated alkanes by whole cells of nitrosomonas europaea. | we have investigated the substrate specificity of ammonia monooxygenase in whole cells of the nitrifying bacterium nitrosomonas europaea for a number of aliphatic halogenated hydrocarbons. to determine the effect of the halogen substituent and carbon chain length on substrate reactivity, we measured the rates of oxidation of the monohalogenated ethanes (fluoroethane, chloroethane, bromoethane, and iodoethane) and n-chlorinated c1 to c4 alkanes by whole cells of n. europaea. for monohalogenated e ... | 1990 | 2394686 |
| detection and analysis of two serotypes of ammonia-oxidizing bacteria in sewage plants by flow cytometry. | two different serotypes of the genus nitrosomonas were isolated from samples of the sewage plant heidelberg. these nitrifiers were enumerated in activated sludge of various other sewage plants after immunofluorescent labeling and staining with propidium iodide by flow cytometry. the concentrations of these serotypes of nitrosomonas spp. were in the range of 0.1 to 2%. also, a test for the determination of the activity of ammonia-oxidizing bacteria was developed. nitrite-oxidizing bacteria were s ... | 1990 | 2403253 |
| some properties of nitrosomonas europaea cytochrome c oxidase (aa3-type) which lacks cua. | from nitrosomonas europaea which had been cultivated in a medium deficient in copper, cytochrome c oxidase (aa3-type) which did not have cua was purified. the oxidase did not show the 830-nm peak and its esr spectrum differed greatly from that of the normal enzyme, which has two copper atoms, cua and cub, per molecule. however, the oxidase which did not have cua showed almost the same cytochrome c oxidizing activity as the normal oxidase. | 1989 | 2542236 |
| autecological study of the chemoautotroph nitrobacter by immunofluorescence. | fluorescent antibodies (fa) prepared for nitrobacter agilis and n. winogradskyi were highly reactive in homologous staining. low-level cross-reactions between the two species were removed by adsorption. all 15 pure-culture isolates of nitrobacter tested reacted strongly with either n. agilis fa or n. winogradskyi fa. all pure-culture isolates from soils were determined to be n. winogradskyi; those from mammoth cave sediments and a cattle waste oxidation ditch were n. agilis. no cross-reaction wa ... | 1974 | 4589121 |
| degradation of trichloroethylene by the ammonia-oxidizing bacterium nitrosomonas europaea. | suspensions of nitrosomonas europaea are shown to cause the complete disappearance of 10 microm trichloroethylene at rates of 1 microm mg protein-1. the reaction continues at nearly this rate for many hours. fresh cells catalyze the reaction in the absence of added ammonium (presumably utilizing endogenous ammonia or stored reductant). in older cells, trichloroethylene degradation depends on the addition of ammonia. acetylene, 2-chloro 6-trichloromethylpyridine and alpha alpha'dipyridyl, which i ... | 1989 | 2930535 |
| absorption bands of multiple b and c cytochromes in bacteria detected by numerical analysis of absorption spectra. | | 1972 | 4625502 |
| a comparative survey of several bacterial aa3-type cytochrome c oxidases. | the aa3-type cytochrome c oxidases purified from nitrobacter agilis, thiobacillus novellus, nitrosomonas europaea, and pseudomonas am 1 were compared. they have haem a and copper atom as the prosthertic groups and show alpha and gamma absorption peaks at around 600 and 440 nm, respectively. each oxidase molecule is composed of two kinds of subunits. the n. agilis oxidase has 2 moles of haem a and 2 atoms of copper in the minimal structural unit composed of one molecule each of the two kinds of s ... | 1985 | 2991467 |
| tetraheme cytochrome c-554 from nitrosomonas europaea. heme-heme interactions and ligand binding. | cytochrome c-554 functions in the ammonia oxidizing system of nitrosomonas europaea. we have investigated its molecular and ligand binding properties and studied the protein with optical, epr, and mössbauer spectroscopies in the ph range from 2 to 13. amino acid, heme, and metal analyses show that the protein has mr = 25,000 and that it contains four c-type hemes per molecule. optical spectra reveal that the heme ligand structures are sensitive to the ph of the medium and that the hemes can bind ... | 1986 | 3003055 |
| isolation of ammonia-oxidizing autotrophic bacteria. | | 1968 | 4883087 |
| growth of nitrosomonas europaea in batch and in continuous culture. | | 1968 | 4884200 |
| n-terminal amino acid sequence of cytochrome c-552 from nitrosomonas europaea. | nitrosomonas europaea is an ammonia-oxidizing bacterium which contains multiple c-type cytochromes. few of these components have been assigned physiological roles, but on the basis of molecular weight and redox potential cytochrome c-552 has been considered to be an analogue of the mitochondrial cytochrome-c family of proteins. we present the n-terminal amino acid sequence (47 residues) of cytochrome c-552 and show that this protein is most closely related to the group of small cytochrome-c comp ... | 1986 | 3004498 |
| cytochrome aa3 from nitrosomonas europaea. | cytochrome c oxidase has been purified from the ammonia oxidizing chemoautotroph nitrosomonas europaea by ion-exchange chromatography in the presence of triton x-100. the enzyme has absorption maxima at 420 and 592 nm in the resting state and at 444 and 598 nm in the dithionite-reduced form; optical extinction coefficient (598 nm minus 640 nm) = 21.9 cm-1 nm-1. the enzyme has approximately 11 nmol of heme a and approximately 11 nmol of copper per mg of protein (lowry procedure). there appear to ... | 1986 | 3023381 |
| effect of solvent, pressure and temperature on reaction rates of the multiheme hydroxylamine oxidoreductase. evidence for conformational change. | hydroxylamine oxidoreductase (hao) of the ammonia-oxidizing bacterium nitrosomonas catalyzes the oxidation: nh2oh + h2o----hno2 + 2e- + 2 h+. the heme-like chromophore p460 is part of a site which binds substrate, extracts electrons and then passes them to the many c hemes of the enzyme. reduction of the c hemes by hydroxylamine is biphasic with apparent first-order rate constants k1 and k2. co binds to ferrous p460 with apparent first-order rate constants, k1,co. in this work we have measured t ... | 1988 | 3416874 |
| nitrite and nitrous oxide production by methylosinus trichosporium. | conditions for the production of nitrite and nitrous oxide by an obligate methanotroph, methylosinus trichosporium (ob 3b), were studied. the rate of nitrite production (v no2-) was correlated with the concentration of ammonia up to 20 mm in the presence of sufficient amounts of oxygen and inversely correlated with the amounts of methane in the system. the rate of nitrous oxide (n2o) production (v n2o) was correlated positively with v no2- and the amount of nitrite produced and inversely with th ... | 1985 | 3921227 |
| spectroscopic evidence for a photosensitive oxygenated state of ammonia mono-oxygenase. | photoinactivation of ammonia oxidation by nitrosomonas europaea cells by near-u.v. light was confirmed and further shown to occur with the same rate constant as loss of bromoethane-oxidation activity. hydroxylamine oxidation was much less photosensitive. protection against inactivation was afforded by anaerobiosis, organic substrates of ammonia mono-oxygenase such as bromoethane, or metal-ion-chelating agents such as thiourea. the presence of 10 mm-nh4+ or 1 mm-hydroxylamine made little differen ... | 1985 | 3922353 |
| 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 |
| suicidal inactivation and labelling of ammonia mono-oxygenase by acetylene. | acetylene brings about a progressive inactivation of ammonia mono-oxygenase, the ammonia-oxidizing enzyme in nitrosomonas europaea. high nh4+ ion concentrations were protective. the inactivation followed first-order kinetics, with a rate constant of 1.5 min-1 at saturating concentrations of acetylene. if acetylene was added in the absence of o2, the cells remained active until o2 was re-introduced. a protective effect was also demonstrated with thiourea, a reversible non-competitive inhibitor of ... | 1985 | 4004794 |
| the partial characterization of purified nitrite reductase and hydroxylamine oxidase from nitrosomonas europaea. | nitrite reductase has been separated from cell-free extracts of nitrosomonas and partially purified from hydroxylamine oxidase by polyacrylamide-gel electrophoresis. in its oxidized state the enzyme, which did not contain haem, had an extinction maximum at 590nm, which was abolished on reduction. sodium diethyldithiocarbamate was a potent inhibitor of nitrite reductase. enzyme activity was stimulated 2.5-fold when remixed with hydroxylamine oxidase, but was unaffected by mammalian cytochrome c. ... | 1974 | 4154745 |
| growth response of nitrosomonas europaea to amino acids. | growth responses of nitrosomonas europaea to individual amino acids or vitamins was observed in log-phase cultures, as was the incorporation of carbon-14 labeled amino acids. nitrite formation and protein synthesis were increased by l-glutamic acid, l-aspartic acid, l-serine, and l-glutamine. l-lysine, l-histidine, l-threonine, l-valine, l-methionine, and l-arginine were inhibitory. the other amino acids had no effect on growth. all of the uniformly labeled amino acids added at low concentration ... | 1967 | 4226683 |
| [microbial ecology of moroccari soils. i. seasonal fluctuations]. | | 1972 | 5077031 |
| a nitrite-reducing enzyme from nitrosomonas europaea. preliminary characterization with hydroxylamine ad electron donor. | | 1968 | 4298926 |
| [analysis of the epr spectra of enzymes containing bivalent copper]. | | 1967 | 4317781 |
| the scope of the eater pollution problem. | | 1971 | 5161226 |
| the antibacterial effect of dry tomato plants, onion peels, and guava leaves on soil microorganisms. | | 1971 | 5172508 |
| solubilization and purification of cytochrome 1 from nitrosomonas. | | 1972 | 4345284 |
| nitrification. | | 1966 | 5326519 |
| the microbial ecology of the activated sludge process. | | 1971 | 4347114 |
| products of sulphide oxidation in extracts of thiobacillus concretivorus. | | 1970 | 5416105 |
| characterization of glutamate dehydrogenase from the ammonia-oxidizing chemoautotroph nitrosomonas europaea. | | 1967 | 4381045 |
| glutamate dehydrogenase in nitrosomon as europaea and the effect of hydroxylamine, oximes and related compounds on its activity. | | 1969 | 4388079 |
| ammonia or ammonium ion as substrate for oxidation by nitrosomonas europaea cells and extracts. | the effect of ph on the k(m) values for ammonia was studied in its oxidation by nitrosomonas cells and cell-free extracts. the k(m) values decreased markedly with increasing ph, suggesting (nh(3)) rather than (nh(4) (+)) as the actual substrate for oxidation. | 1974 | 4422399 |
| intermediary metabolism of carbon compounds by nitrifying bacteria. | | 1970 | 5426270 |
| [the effect of temperature on the rat of oxidation of ammonia to nitrate by mixed cultures of nitrifying organisms (author's transl)]. | | 1974 | 4468751 |
| growth of obligate autotrophic bacteria on glucose in a continuous flow-through apparatus. | nitrosomonas europaea, nitrobacter agilis, thiobacillus denitrificans, t. neapolitanus, and t. thioparus (all obligate autotrophic bacteria) have been grown in dialysis culture, on glucose salts media, in the absence of their specific inorganic energy source. metabolic products for n. agilis grown on nitrite salts medium were identified as keto acids. pyruvic acid inhibited this organism at 5 x 10(-5)m. keto acids were not inhibitory for the thiobacilli grown on thiosulfate medium. however, when ... | 1972 | 4551747 |
| phosphoenolpyruvate carboxylase of thiobacillus thiooxidans. kinetic and metabolic control properties. | | 1972 | 4552310 |
| growth of mixed cultures of autotrophic and heterotrophic organisms. | | 1972 | 4622985 |
| [determination of the activity of nitrifying bacteria in surface waters by a modified bod-test]. | | 1972 | 4660907 |
| inhibition of nitrifying chemolithotrophic bacteria by several insecticides. | | 1968 | 5636842 |
| specific inhibitors of ammonia oxidation in nitrosomonas. | the following compounds or treatments have been shown to inhibit the oxidation of ammonia, but not the oxidation of hydroxylamine in cells of nitrosomonas: (i) metal-binding agents such as allylthiourea or potassium cyanide; (ii) compounds such as skf 525 which interact with cytochrome p-450 of mammalian microsomes; (iii) carbon monoxide; (iv) inhibitors of catalase, peroxidase, and amine oxidases such as thiosemicarbazide, ethylxanthate, and iproniazid, respectively; (v) uncouplers of oxidative ... | 1973 | 4725614 |
| deoxyribonucleic acid base composition and taxonomy of thiobacilli and some nitrifying bacteria. | | 1968 | 5677980 |
| calorimetric measurement of free energy utilization by nitrosomonas and nitrobacter. | | 1968 | 4885091 |
| microbial formation of nitrite in ventilating shafts. | | 1968 | 5690682 |
| the biochemistry of nitrifying microorganisms. | | 1969 | 4893925 |
| [effect of light on the metabolism of non-photosynthesizing microorganisms]. | | 1971 | 4935598 |
| presence and function of disclinations in surface coats of unicellular organisms. | | 1971 | 4938847 |
| comparison of the morphology and deoxyribonucleic acid composition of 27 strains of nitrifying bacteria. | the gross morphology, fine structure, and per cent guanine plus cytosine (gc) composition of deoxyribonucleic acid of 27 strains of nitrifying bacteria were compared. based on morphological differences, the ammonia-oxidizing bacteria were separated into four genera. nitrosomonas species and nitrosocystis species formed one homogenous group, and nitrosolobus species and nitrosospira species formed a second homogenous group in respect to their deoxyribonucleic acid gc compositions. similarly, the ... | 1971 | 4939767 |
| effect of mixing on the washout and steady-state performance of continuous cultures. | | 1970 | 4950531 |
| energy-coupling mechanisms in chemolithotrophic bacteria. | | 1968 | 4972376 |