Nitrate reductase structure

Chlorella vulgaris nitrate reductase structure, 3,1438 Chlorides... 

Fernandez, E., Schnell, R., Ranum, L.P.W., Hussey, S.C., Silflow, C.D. Lefebvre, P. (1989). Isolation and characterization of the nitrate reductase structural gene of Chlamydomonas reinhardtii. Proceedings of the National Academy of Sciences (USA) 86, 6449-53. 

Wilkinson, J.Q. Crawford, N.M. (1991). Identification of the Arabidopsis CHL3 gene as the nitrate reductase structural gene NIA2. The Plant Cell 3, 461-71. 

Campbell, W. (1999). Nitrate reductase structure, function and regulation Bridging the gap between biochemistry and physiology. Annu. Rev. Plant Physiol. Plant Mol. Biol. 50, 277—305. 

The enzyme activity is induced by both NOj" and Mo when in the presence of each other. The induction of enzyme activity by N03" is a slow process and requires mRNA-dependent synthesis of apoprotein, whereas the induction of enzyme activity by Mo is much faster, as it involves only rapid activation of the apoprotein by Mo (Jones et al., 1976, 1978). Notion and Hewitt (1979) showed that the Mo-free apoenzyme could be activated by addition of Mo complex obtained from acid washings of the native enzyme. Tungsten (W) can substitute for Mo in nitrate reductase, but the enzyme activity is decreased (Heimer, Wray, and Filner, 1969), as the formation of an active Mo cofactor is prevented. In an experiment with W-treated tobacco (Nicotiana tabacum) plants supplied with N as NOs , Deng, Moureaux, and Caboche (1989) reported a decrease in nitrate reductase activity, but several-fold increases in the accumulation of nitrate reductase apoprotein and corresponding mRNA because of excessive expression of a nitrate reductase structural gene. 

Deng, M., Moureaux, T., and Caboche, M. (1989). Tungstate and molybdenum analog inactivating nitrate reductase, deregulates the expression of the nitrate reductase structural gene. Plant Physiol. 91 304-9. 

Cerium tetrakis(acetylacetonate), 1114 Cesium complexes crown ethers, 40 Chevrel phases, 1321 Chlorella vulgaris nitrate reductase structure, 1438 Chlorine cations... 

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

The element molybdenum (atomic weight 95.95) constitutes 0.08% of the weight of nitrate reductase. If the molecular weight of nitrate reductase is 240,000, what is its likely quaternary structure ... 

It is not clear why some organisms have two 14-3-3 isoforms while others have up to 12. Binding 14-3-3 inhibits the plant enzyme nitrate reductase and there appears to be no selectivity between plant 14-3-3 isoforms in fact yeast and human isoforms appear to work equally as well in vitro. The best example where selectivity has been demonstrated is human 14-3-3o. 14-3-3o Preferential homodimerizes with itself and crystallization revealed a structural basis for this isoform s dimerization properties as well as for its specific selectivity for target binding proteins. Here partner specificity is the result of amino acid differences outside of the phosphopeptide-binding cleft. 

The molyhdopterin cofactor, as found in different enzymes, may be present either as the nucleoside monophosphate or in the dinucleotide form. In some cases the molybdenum atom binds one single cofactor molecule, while in others, two pterin cofactors coordinate the metal. Molyhdopterin cytosine dinucleotide (MCD) is found in AORs from sulfate reducers, and molyhdopterin adenine dinucleotide and molyb-dopterin hypoxanthine dinucleotide were reported for other enzymes (205). The first structural evidence for binding of the dithiolene group of the pterin tricyclic system to molybdenum was shown for the AOR from Pyrococcus furiosus and D. gigas (199). In the latter, one molyb-dopterin cytosine dinucleotide (MCD) is used for molybdenum ligation. Two molecules of MGD are present in the formate dehydrogenase and nitrate reductase. 

NiFe hydrogenase, see NiFe hydrogenase nitrate reductase, 47 3, 5,13-14, 396,403-406, 472, 475 NMR studies, 4na5 -Tll electron relaxation times, 47 252-257 polypeptide folding, 47 271-276 reduction potential, 47 265-266 solution structure, 47 266-271 valence delocalization, XJOSl, 259, 261-265... 

Study by X-ray absorption spectroscopy of the extended X-ray absorption fine structure (EXAFS) has provided estimates of both the nature and the number of the nearest neighboring atoms around the Mo. The EXAFS spectra of xanthine dehydrogenase and of nitrate reductase from Chlorella confirmed the... 

Both assimilatory and dissimilatory nitrate reductases are molybdoenzymes, which bind nitrate at the molybdenum. EXAFS studies1050 have shown that there are structural differences between the assimilatory nitrate reductase from Chlorella vulgaris and the dissimilatory enzyme from E. coli. The Chlorella enzyme strongly resembles sulfite oxidase1050,1053 and shuttles between mon-and di-oxo forms, suggesting an oxo-transfer mechanism for reduction of nitrate. This does not appear to be the case for the E. coli enzyme, for which an oxo-transfer mechanism seems to be unlikely. The E. coli enzyme probably involves an electron transfer and protonation mechanism for the reduction of nitrate.1056 It is noteworthy that the EXAFS study on the E. coli nitrate reductase showed a long-distance interaction with what could be an electron-transfer subunit. 

Daniel-Vedele, F., Dorbe, M.F., Caboche, M. Rouze, P. (1989). Cloning and analysis of the tomato nitrate reductase-encoding gene protein domain structure and amino acid homologies in higher plants. Gene 85, 371-80. 

Meyer, C., Levin, J.M., Roussel, J.M. Rouze, P. (1991). Mutational and structural analysis of the nitrate reductase haem domain of Nicotiana plumbaginifolia. Journal of Biological Chemistry 266, 20561-6. 

Okamoto, P.M., Fu, Y.-H. Marzluf, G.A. (1991). Nit-3, the structural gene of nitrate reductase in Neurospora crassa nucleotide sequence and regulation of mRNA synthesis and turnover. Molecular and General Genetics 227, 213-23. 

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