Complete structure of the hydrophilic domain in the porcine NADPH-cytochrome P-450 reductase.
The 622-residue amino acid sequence of the hydrophilic domain in the porcine NADPH-cytochrome P-450 reductase (EC 1.6.2.4) is reported. The structural data required to complete the sequences published previously [Vogel, Kaiser, Witt & Lumper (1985) Biol. Chem. Hoppe-Seyler 366, 577-587] and to establish the primary structure of the porcine hydrophilic domain have been obtained by sequencing proteolytic subfragments derived from CNBr fragments and by characterizing the overlapping S-[14C]methylmethionine-containing peptides isolated from tryptic digests of the [14C]methyl-labelled hydrophilic domain. The hydrophilic domain displays 91.8% positional identity with that of the corresponding domain in the rat NADPH-cytochrome P-450 reductase. The region Val528-Ser678 in the NADPH-cytochrome P-450 reductase shows a significant homology to the sequence Ile165-Tyr314 in the spinach ferredoxin-NADP+ oxidoreductase. A model for the secondary structure of the hydrophilic domain has been derived by computer-assisted analysis of the amino acid sequence. Cys472 and Cys566 are protected against chemical modification in the NADP+ complex of the NADPH-cytochrome P-450 reductase.
D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D005420:Flavoproteins / Q000378:metabolism; D008099:Liver / Q000201:enzymology; D009249:NADP / Q000378:metabolism; D009251:NADPH-Ferrihemoprotein Reductase / Q000235:genetics*; D010446:Peptide Fragments / Q000235:genetics; D010710:Phosphates / Q000378:metabolism; D011487:Protein Conformation; D051381:Rats; D013552:Swine
D005420:Flavoproteins; D010446:Peptide Fragments; D010710:Phosphates; D009249:NADP; D009251:NADPH-Ferrihemoprotein Reductase