cDNA cloning and expression of a novel cytochrome p450 (cyp4f12) from human small intestine.
A cDNA encoding a novel human CYP4F enzyme (designated CYP4F12) was cloned by PCR from a human small intestine cDNA library. RT-PCR analysis demonstrated that CYP4F12 is expressed in human small intestine and liver. This cDNA contains an entire coding region of a 524-amino-acid protein that is 81.7, 78.3, and 78.2% identical to CYP4F2, CYP4F3, and CYP4F8, respectively. When expressed in Saccharomyces cerevisiae, the P450 catalyzes leukotriene B(4) omega-hydroxylation and arachidonic acid omega-hydroxylation, typical reactions of CYP4F isoforms. Their activity levels are, however, much lower than those of CYP4F2. Interestingly, CYP4F12 catalyzes the hydroxylation of the antihistamine ebastine with significantly higher catalytic activity relative to CYP4F2 (385 vs 5 pmol/min/nmol P450). These results indicate that CYP4F12 has a different profile of substrate specificity from other CYP4F isoforms, enzymes responsible for metabolizing endogenous autacoids, therefore suggesting that it may play an important role in xenobiotic biotransformation in the human small intestine.
Hashizume
T
T
Developmental Research Laboratories, Dainippon Pharmaceutical Company, Ltd., 33-94 Enoki-cho, Suita, Osaka, 564-0053, Japan. takanori-hashidume@dainippon-pharm.co.jp
Imaoka
S
S
Hiroi
T
T
Terauchi
Y
Y
Fujii
T
T
Miyazaki
H
H
Kamataki
T
T
Funae
Y
Y
D000595:Amino Acid Sequence; D016718:Arachidonic Acid / Q000378:metabolism; D001189:Aryl Hydrocarbon Hydroxylases; D001483:Base Sequence; D002090:Butyrophenones / Q000378:metabolism; D002384:Catalysis; D003001:Cloning, Molecular; D003577:Cytochrome P-450 Enzyme System / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics*; D000072470:Cytochrome P450 Family 4; D018076:DNA, Complementary / Q000378:metabolism; D015723:Gene Library; D006801:Humans; D007421:Intestine, Small / Q000378:metabolism*; D007975:Leukotriene B4 / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D006899:Mixed Function Oxygenases / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics*; D008969:Molecular Sequence Data; D010880:Piperidines / Q000378:metabolism; D020033:Protein Isoforms; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
D002090:Butyrophenones; D018076:DNA, Complementary; D010880:Piperidines; D020033:Protein Isoforms; D007975:Leukotriene B4; D016718:Arachidonic Acid; D003577:Cytochrome P-450 Enzyme System; D006899:Mixed Function Oxygenases; D001189:Aryl Hydrocarbon Hydroxylases; C422180:CYP4F12 protein, human; C120451:CYP4F8 protein, human; D000072470:Cytochrome P450 Family 4; C117480:CYP4F2 protein, human; C040780:leukotriene B4 20-hydroxylase; C058249:ebastine