Analysis of a ferric leghemoglobin reductase from cowpea (Vigna unguiculata) root nodules
Por:
Luan P., Aréchaga-Ocampo E., Sarath G., Arredondo-Peter R., Klucas R.V.
Publicada:
1 ene 2000
Resumen:
Ferric leghemoglobin reductase (FLbR), an enzyme reducing ferric leghemoglobin (Lb) to ferrous Lb, was purified from cowpea (Vigna unguiculata) root nodules by sequential chromatography on hydroxylapatite followed by Mono-Q HR5/5 FPLC and Sephacryl S-200 gel filtration. The purified cowpea FLbR had a specific activity of 216 nmol Lb2+O2 formed min-1 mg-1 of enzyme for cowpea Lb3+ and a specific activity of 184 nmol Lb2+O2 formed min-1 mg-1 of enzyme for soybean Lb3+. A cDNA clone of cowpea FLbR was obtained by screening a cowpea root nodule cDNA library. The nucleotide sequence of cowpea FLbR cDNA exhibited about 88% similarity with soybean (Glycine max) FLbR and 85% with pea (Pisum sativum) dihydrolipoamide dehydrogenase (DLDH, EC 1.8.1.4) cDNAs. Conserved regions for the FAD-binding site, NAD(P)H-binding site, and disulfide active site were identified among the deduced amino acid sequences of cowpea FLbR, soybean FLbR, pea DLDH and other enzymes in the family of the pyridine nucleotide-disulfide oxido-reductases. (C) 2000 Published by Elsevier Science Ireland Ltd.
Filiaciones:
Luan P.:
Department of Biochemistry, Beadle Ctr., Univ. Nebraska-Lincoln, Lincoln, NE 68588-0664, United States
Aréchaga-Ocampo E.:
Ctro. Invest. Sobre Fijacion N., Univ. Nac. Auton. Mex., Apdo. P., Morelos, Mexico
Sarath G.:
Department of Biochemistry, Beadle Ctr., Univ. Nebraska-Lincoln, Lincoln, NE 68588-0664, United States
Arredondo-Peter R.:
Ctro. Invest. Sobre Fijacion N., Univ. Nac. Auton. Mex., Apdo. P., Morelos, Mexico
Klucas R.V.:
Department of Biochemistry, Beadle Ctr., Univ. Nebraska-Lincoln, Lincoln, NE 68588-0664, United States
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