Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.7.1.4 (nitrite reductase)
 1,847 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. The dye-linked methanol dehydrogenase from Paracoccus denitrificans grown aerobically on methanol has been purified and its properties compared with similar enzymes from other bacteria. It was shown to be specific and to have high affinity for primary alcohols and formaldehyde as substrate, ammonia was the best activator and the enzyme could be linked to reduction of phenazine methosulphate. 2. Paracoccus denitrificans could be grown anaerobically on methanol, using nitrate or nitrite as electron acceptor. The methanol dehydrogenase synthesized under these conditions could not be differentiated from the aerobically-synthesized enzyme. 3. Activities of methanol dehydrogenase, formaldehyde dehydrogenase, formate dehydrogenase, nitrate reductase and nitrite reductase were measured under aerobic and anaerobic growth conditions. 4. Difference spectra of reduced and oxidized cytochromes in membrane and supernatant fractions of methanol-grown P. denitrificans were measured. 5. From the results of the spectral and enzymatic analyses it has been suggested that anaerobic growth on methanol/nitrate is made possible by reduction of nitrate to nitrite using electrons derived from the pyridine nucleotide-linked dehydrogenations of formaldehyde and formate, the nitrite so produced then functioning as electron acceptor for methanol dehydrogenase via cytochrome c and nitrite reductase.
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PMID:Aerobic and anaerobic growth of Paracoccus denitrificans on methanol. 71 72

The denitrifying capacity of 15 strains of Bacillus licheniformis was evaluated. In general, N2 production by the cultures on complex media containing NO3- is irregular and quite slow and three of the strains never produce gas. Bacillus licheniformis grows rapidly in anaerobiosis on peptone medium containing NO3- which is reduced to NO2-. None of the strains grow in peptone medium with NO2- or N2O as the respiratory substrate, nor do they grow under an atmosphere of 10% NO-90% N2. Denitrification was studied in cell suspensions using gas chromatography. N2O production from NO3- or NO2- is always weak at best; nitric oxide is reduced to N2O at an appreciable rate. All the strains synthesize nitrate reductase A in anaerobiosis when NO3- is present. In cell extracts, nitrite reductase activity is always negligible or nil with tetramethyl-p-phenylenediamine as an electron donor.
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PMID:[Denitrification by Bacillus licheniformis]. 75 76

Mutation in at least ten genes can result in chlorate reistance in Aspergillus nidulans. Mutation in seven of these genes also results in the inability to use nitrate as nitrogen source. The various classes of resistant mutant obtained occur in different proportions, depending on whether or not a mutagenic treatment is employed, and also on which nitrogen source is used for selection. The prinicipal effect of mutagen arises because mutations in the niaD gene, the nitrate reductase structural gene, are relatively much commoner when no mutagen is used than after treatment with N-methyl-N'-nitro-N-nitrosoguanidine. This may be connected with the finding that deletions involving the niaD gene are relatively more common among samples of spontaneous niaD mutants. Some of these deletions extend to the neighbouring niiA gene, the structural gene for nitrite reductase. The selection procedures used were designed to avoid bias in favour of any particular chlorate resistant phenotype. Even if biases existed however, these could not account for the variation found from nitrogren source to nitrogen source in the proportions of certain resistant classes having apparently identical chlorate resistance phenotypes.
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PMID:Cholorate toxicity in Aspergillus nidulans: the selection and characterisation of chlorate resistant mutants. 77 8

The strains were isolated from soil by enrichment in a liquid minimal medium containing ethanol, acetate, succinate, L-malate or tartrate, under an N2O atmosphere at 32 degrees C. All fourteen strains can use the following 25 sources of carbon and energy under aerobic conditions: glycerate, ethanol, propanol, acetate, butyrate, malonate, succinate, glutarate, sebacate, glycollate, L-lactate, D-lactate, L-malate, DL-3-hydroxybutyrate, pyruvate, fumarate, itaconate, mesaconate, crotonate, L-alpha-alanine, D-alpha-alanine, L-leucine, asparagine, L-tyrosine, and L-proline. They hydrolyze Tween 80 but not gelatin. Nitrate is used as nitrogen source. Nitrate reductase A and respiratory nitrite reductase are present. Four of the strains are clearly and easily distinguishable from the others on the basis of six characters: special morphology of colonies; in ability to use isovalerate and DL-valine, inability to use glucose, absence of exocellular amylase, and high level of metapyrocatechase. Their G + C content is 66-67%. One of the strains is distinct from the others by the yellow pigmentation of its colonies, its ability to use D-glucuronate, trehalose, D-sorbitol and citraconate, ability to grow at 4 degrees but not at 40 degrees, and a lower G + C content: 63%. One strain accumulates poly-beta-hydroxybutyrate. This work confirms the well-known, wide variability of the bacteria belonging to the P. stutzeri group. Denitrification by two of the strains was quantitatively studied using cell suspensions. Cells from NO-3-containing anaerobic cultures reduce NO-3, NO-2 and NO to N2O and N2; they reduce slowly N2O to N2. Cells grown in anaerobic cultures under N2O also reduce NO-3, NO-2 and NO to N2O and N2 but they reduce N2O rapidly to N2.
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PMID:[Study of 14 denitrifying soil bacteria of the "pseudomonas stutzeri" group isolated by enrichment culture in the presence of nitrous oxide (author's transl)]. 86 7

The described bacterium was isolated by enrichment culture in peptone broth inoculated with garden soil, pasteurized and then put to incubate under N2O at 32 degrees. It is a Gram-negative rod, motile with peritrichous flagella, and producing oval spores without exosporium in swollen sporangia. However, cells have the thick walls, mesosomes and persistant septa characteristic of Gram-positive bacteria. It lacks fermentative activity, does not attack carbohydrates, has complex growth requirements, and will grow anaerobically only if one of the following electron acceptors is present: NO3, NO2, N2O, S4O6, and fumarate. Nitrate, nitrite, and nitrous oxide are denitrified with production of N2. The microorganism is mesophilic, gives a positive oxidase reaction, synthesizes a type of c cytochrome, and does not hydrolyse gelatin, starch nor "Tween 80". The following enzymes are present: nitrate reductase A, respiratory nitrite reductase, tetrathionate and fumarate reductases, L-glutamate dehydrogenase, and superoxide dismutase. The following enzymes are absent: thiosulfate reductase, urease, lecithinase, arginine dihydrolase, L-alanine dehydrogenase, phenylalanine desaminase, and catalase. The GC% of its DNA is 39. The bacterium described can be considered to be a new species. We propose the name Bacillus azotoformans n. sp.
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PMID:[A new, sporulating, denitrifying, mesophilic bacterium: Bacillus azotoformans N. SP. (author's transl)]. 102 Aug 72

The roles of molybdenum and iron in the enzymes of the assimilatory nitrate-reducing system from Azotobacter chroococcum have been investigated. 1. By adding 99 Mo-molybdate to a cell culture of A. chrocococcum with nitrate as the nitrogen source, it has been possible to incroporate the radioactive metal into a purified preparation of the enzyme nitrate reductase. 2. When 185 W-tungstate was supplied to a culture medium lacking added molybdate, a 185 W-labelled nitrate reductase preparation with negligible activity could be obtained. This in vivo incorporation of tungsten was competitively hindered by molybdenum. 3. The cellular level of nitrite reductase activity gradually increased in response to the addition of increasing amounts of iron to the culture medium. Under the same conditions, of the level of nitrate reductase activity was not affected.
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PMID:Molybdenum and iron as functional consitituents of the enzymes of the nitrate-reducing system of Azotobacter chroococcum. 111 63

Suspensions of denitrifying cells of Pseudomonas perfectomarinus reduced nitrate and nitrate as expected to dinitrogen; but, in the presence of acetylene, nitrous oxide accumulated when nitrate or nitrate was reduced. When supplied at the outset in place of nitrate and nitrate, nitrous oxide was rapidly reduced to dinitrogen by cells incubated in anaerobic vessels in the absence of acetylene. In the presence of 0.01 atmospheres of acetylene, however, nitrous oxide was not reduced. Ethylene was not produced, nor did it influence the rate of nitrous oxide reduction when provided instead of acetylene. Cells exposed to 0.01 atmospheres of acetylene for as long as 400 min were able to reduce nitrous oxide after removal of acetylene at a rate comparable to that of cells not exposed to acetylene. Acetylene did not affect the production or functioning of assimilatory nitrate or nitrite reductase in axenic cultures of Enterobacter aerogenes or Trichoderma uride. While exposed to acetylene, bacteria in marine sediment slurries produced measurable quantities of nitrous oxide from glucose- or acetate-dependent reduction of added nitrate. Possible use of acetylene blockage for measurement of denitrification in unamended marine sediments is discussed.
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PMID:Blockage by acetylene of nitrous oxide reduction in Pseudomonas perfectomarinus. 126 47

A tobacco nitrite reductase (NiR) cDNA and its corresponding gene were isolated from cDNA and genomic libraries. An NiR antisense mRNA was expressed in transgenic tobacco under the control of a double 35S promoter. Transformants were obtained on a medium containing ammonium as the sole source of nitrogen. One plant growing normally on ammonium but displaying drastically reduced development and chlorotic leaves when grown on nitrate as the sole source of nitrogen was studied further. This plant accumulated nitrite fivefold over wild-type level and showed reduced amounts of ammonium (11% wild-type level), glutamine (19%), and total protein (8%). NiR mRNA and activity were below detectable levels. Under these conditions, nitrate reductase (NR) activity and mRNA were overexpressed, suggesting that N-metabolites resulting from nitrate reduction are responsible for the repression of the expression of the NR gene, independently from the presence or absence of a functional NR protein.
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PMID:Inhibition of tobacco nitrite reductase activity by expression of antisense RNA. 128 56

Tn5 was used to generate mutants that were deficient in the dissimilatory reduction of nitrite for Pseudomonas sp. strain G-179, which contains a copper nitrite reductase. Three types of mutants were isolated. The first type showed a lack of growth on nitrate, nitrite, and nitrous oxide. The second type grew on nitrate and nitrous oxide but not on nitrite (Nir-). The two mutants of this type accumulated nitrite, showed no nitrite reductase activity, and had no detectable nitrite reductase protein bands in a Western blot (immunoblot). Tn5 insertions in these two mutants were clustered in the same region and were within the structural gene for nitrite reductase. The third type of mutant grew on nitrate but not on nitrite or nitrous oxide (N2O). The mutant of this type accumulated significant amounts of nitrite, NO, and N2O during anaerobic growth on nitrate and showed a slower growth rate than the wild type. Diethyldithiocarbamic acid, which inhibited nitrite reductase activity in the wild type, did not affect NO reductase activity, indicating that nitrite reductase did not participate in NO reduction. NO reductase activity in Nir- mutants was lower than that in the wild type when the strains were grown on nitrate but was the same as that in the wild type when the strains were grown on nitrous oxide. These results suggest that the reduction of NO and N2O was carried out by two distinct processes and that mutations affecting nitrite reduction resulted in reduced NO reductase activity following anaerobic growth with nitrate.
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PMID:Characterization of Tn5 mutants deficient in dissimilatory nitrite reduction in Pseudomonas sp. strain G-179, which contains a copper nitrite reductase. 132 60

The sequence of an mRNA encoding nitrite reductase (NiR, EC 1.7.7.1.) from the tree Betula pendula was determined. A cDNA library constructed from leaf poly(A)+ mRNA was screened with an oligonucleotide probe deduced from NiR sequences from spinach and maize. A 2.5 kb cDNA was isolated that hybridized to an mRNA, the steady-state level of which increased markedly upon induction with nitrate. The nucleotide sequence of the cDNA contains a reading frame encoding a protein of 583 amino acids that reveals 79% identity with NiR from spinach. The transit peptide of the NiR precursor from birch was determined to be 22 amino acids in size by sequence comparison with NiR from spinach and maize and is the shortest transit peptide reported so far. A graphical evaluation of identities found in the NiR sequence alignment revealed nine well conserved sections each exceeding ten amino acids in size. Sequence comparisons with related redox proteins identified essential residues involved in cofactor binding. A putative binding site for ferredoxin was found in the N-terminal half of the protein.
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PMID:Sequence of a cDNA encoding nitrite reductase from the tree Betula pendula and identification of conserved protein regions. 134 45


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