Nitrate reductase Escherichia coli

Fig. 6. Representative EPR spectra displayed by trinuclear and tetranucleEir iron-sulfur centers, (a) and (b) [3Fe-4S] + center in the NarH subunit of Escherichia coli nitrate reductase and the Ni-Fe hydrogenase fromD. gigas, respectively, (c) [4Fe-4S] + center in D. desulfuricans Norway ferredoxin I. (d) [4Fe-4S] center in Thiobacillus ferrooxidans ferredoxin. Experimental conditions temperature, 15 K microwave frequency, 9.330 GHz microwave power, (a) 100 mW, (b) 0.04 mW, (c) smd (d) 0.5 mW modulation amplitude (a), (c), (d) 0.5 mT, (b) 0.1 mT.

Chaudhry GR, MacGregor CH (1983) Cytochrome b from Escherichia coli nitrate reductase. Its properties and association with the enzyme complex. J Biol Chem 258 5819-5827 Chaudhry GR, Suzuki I, Lees H (1980) Cytochrome oxidase of Nitrobacter agilis isolation by hydrophobic chromatography. Can J Microbiol 26 1270-1274 Chaudhuri SK, Lack JG, Coates JD (2001) Biogenic magnetite formation through anaerobic biooxidation of Fe(II). Appl Environ Microbiol 67 2844—2848 Cheeseman P, Toms-Wood A, Wolfe RS (1972) Isolation and properties of a fluorescent-compound, Factor 420, from Methanobacterium strain M.o.H. J Bacteriol 112 527-531... 

Trinuclear clusters have been detected in over 20 proteins as well as a number of enzymes, among them aconitase, beef heart succinate-ubiquinone oxidoreductase (120), Escherichia coli nitrate reductase (121), E. coli fumarate reductase (122), and succinate dehydrogenase (123). Selected instances of the occurrence of [3Fe-4S] clusters are listed in Table II. Because of the paramagnetic ground states of both oxidation levels, these clusters can be uniquely identified by a number of spectroscopic techniques. Among these, Mossbauer spectroscopy in applied magnetic fields (124, 128, 132, 141-143) and low temperature MCD spectroscopy (127, 138, 144-146) are decisive. While there are small spectroscopic differences among certain [3Fe-4S] centers, the similarities dominate and support the essential structure 3 for all. In a number of the earlier papers on protein... 

Escherichia coli nitrate reductase structure, 1438 Europium complexes -diketones, 1081 dipositive oxidation state hydrated ions, 1109... 

This, the largest and most diverse family of Mo and W enzymes, has been the subject of numerous XAS investigations. One early application of the method to this family was to Escherichia coli nitrate reductase, which gave the first hints of an active site that had four sulfur donors, and that difficulty in analysis might arise from sample heterogeneity, both harbingers of the complexity that was later to become apparent for this family of enzymes. 

A strain of Escherichia coli produces a naphthotriazole from 2,3-diaminonaphthalene and nitrite that is formed from nitrate by the action of nitrate reductase. The initial product is NO, which is converted by reactions with oxygen into the active nitrosylating agent that reacts chemically with the amine (Ji and Hollocher 1988). A comparable reaction may plausibly account for the formation of dimethylnitrosamine by Pseudomonas stutzeri during growth with dimethylamine in the presence of nitrite (Mills and Alexander 1976) (Figure 2.2f). 

The conditions under which these function and their regulation depend on the organism. For example, in Escherichia coli, oxygen represses the synthesis of the other reductases, and under anaerobic conditions the reductases for fumarate, DMSO, and TMAO are repressed by nitrate. This does not apply to Wolinella succinogenes in which sulfur represses the synthesis of the more positive electron acceptors nitrate and fumarate (Lorenzen et al. 1993). The DMSO reductase from Escherichia coli (Weiner et al. 1988) has a broad substrate versatility, and is able to reduce a range of sulfoxides and A-oxides. Anaerobic sulfate reduction is not discussed here in detail. 

Avazeri C, R Turner, J Pommier, J Weiner, GG Giordano, A Vermeglio (1997) Tellurite resistance activity of nitrate reductase is responsible for the basal resistance of Escherichia coli to tellurite. Microbiology (UK) 143 1181-1189. 

Nitrate reductase ) Escherichia coli Reduced methyl viologen NO3 ... 

Ji, X.-B, and Hollocher, T. C. (1989). Nitrate reductase of Escherichia coli as a NO-pro-ducing nitrite reductase. Biochem. Arch. 5, 61-66. 

Nitrate reductase (dissimilatory) Escherichia coli 200000 1 4Fe4S4... 

Hyde, G.E. Campbell, W.H. (1990). High-level expression in Escherichia coli of the catalytically active flavin domain of corn leaf NADH-nitrate, reductase and its comparison to human NADH-cytochrome b5 reductase. Biochemical and Biophysical Research Communications 168, 1285-91. 

Figure 7 The modus operandi of nitrate reductase (a) assimilatory nitrate reductase (plants, fungi, algae) (b) respiratory (dissimilatory) nitrate reductase (.Escherichia coli, Pseudomonas).

IV.C.3. The Molybdenum Site of Respiratory Nitrate Reductase (Escherichia coli)... 

Kapralek, F., Jechova, E., and Otavova, M. (1982) Two sites of oxygen control in induced synthesis of respiratory nitrate reductase in Escherichia coli. J. Bacteriol. 149, 1142-1145. 

That hydroxylamine might not be an obligatory intermediate, or occur as a free intermediate, in the reduction of nitrite to ammonia is suggested by the properties of nitrite reductases of Azotobacter chroococcum and Escherichia coli. The former is an adaptive enzyme, the formation of which requires nitrate or nitrite in the culture (31,2). It is FAD-depen-dent and presumably contains metals and p-mercuribenzoate inhibitable... 

Blasco, F., lobbi, C., Giordano, G., Chippaux, M., and Bonnefoy, V., 1989, Nitrate reductase from Escherichia coli completion of the nucleotide sequence of the nar operon and reassessment of the role of the a and 5 subunits in iron binding and electron transfer. Mol. Gen. Genet. 218 249n256. 

Buc, J., Santini, C.-L., Blasco, F., Giordani, R., C rdenas, M. L., Chippaux, M., Comish-Bowden, A., and Giordano, G., 1995, Kinetic studies of a soluble oP complex of nitrate reductase A from Escherichia coli. Use of various (xP mutants with altered P subunits, Eur. J. Biochem. 234 766n772. 

Campbell, W. H., 1992, Expression in Escherichia coli of cytochrome c reductase activity from a maize NADH nitrate reductase complementary DNA, Plant Physiol. 99 693fi... 

Thomas, G., Potter, L., and Cole, J. A., 1999,The periplasmic nitrate reductase from Escherichia coli a heterodimeric molyhdoprotein with a douhle-arginine signal sequence and an unusual leader peptide cleavage site, FEMS Microbiol. Lett. 174 167nl71. 

Promoter region of the nar operon, which encodes nitrate reductase in Escherichia coli. The promoter is generally only maximally induced under anaerobic conditions. It has been shown that the nar promoter in some strains of Escherichia coli can be induced under conditions of very low oxygen tension in the presence of nitrate. This observation has been used to develop some useful processes for recombinant protein expression in Escherichia coli. See Li, S.F. and DeMoss, J.A., Promoter region of the nar operon of Escherichia coli nucleotide sequence and transcription initiation signals, J. Bacteriol. 169, 4614- 620, 1987 Han, S.J., Chang,... 

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