Purification and characterization of two new cytochrome P-450 related to CYP2C subfamily from rabbit small intestine microsomes.
Two forms of cytochrome P-450, designated P-450id and P-450ie, were purified to specific contents of 14.3 and 15.0 nmol of P-450/mg of protein, respectively, from small intestine mucosa microsomes of rabbits. P-450id and P-450ie showed apparent molecular weights of 50 and 49 kDa, respectively, on SDS-PAGE. Both P-450s catalyzed N-demethylation of nitrosodimethylamine. The NH2-terminal amino acid sequence (first 19 residues) of P-450id exhibited 74-90% identity with those of six members of the rabbit P-450 2C subfamily, except for P-450 2C3. Similarly, the NH2-terminal sequence (first 22 residues) of P-450ie showed 73-86% identity with those of the same members of the rabbit P-450 2C subfamily. The peptide mapping patterns of the two P-450s were quite different from each other. In addition, P-450id did not cross-react with the guinea-pig antibodies against P-450ie. The results indicate that rabbit small intestine mucosa contain two new distinct forms of P-450s, both of which may be classified into the 2C subfamily.
Shimizu
Y
Y
Toneyama Institute for Tuberculosis Research, Osaka City University Medical School, Toyonaka, Japan.
Kusunose
E
E
Kikuta
Y
Y
Arakawa
T
T
Ichihara
K
K
Kusunose
M
M
D000595:Amino Acid Sequence; D000818:Animals; D003577:Cytochrome P-450 Enzyme System / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D007413:Intestinal Mucosa / Q000201:enzymology*; D007421:Intestine, Small / Q000201:enzymology*; D007527:Isoenzymes / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D008297:Male; D008861:Microsomes / Q000201:enzymology; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010449:Peptide Mapping; D011817:Rabbits; D013379:Substrate Specificity
D007527:Isoenzymes; D003577:Cytochrome P-450 Enzyme System