Cloning and expression of a novel form of leukotriene B4 omega-hydroxylase from human liver.
We have isolated and sequenced a cDNA for human liver LTB4 omega-hydroxylase. The cDNA encoded a protein of 520 amino acids with a molecular weight of 59,853 Da. The cDNA-deduced amino acid sequence showed 87.3% homology to that of human polymorphonuclear leukocytes (PMN) LTB4 omega-hydroxylase (CYP4F3). Northern blot analysis revealed that the mRNA hybridized to the specific cDNA fragment is expressed in human liver, but not in human PMN. The microsomes from yeast cells transfected with the cDNA catalyzed the omega-hydroxylation of LTB4 with a Km of 44.8 microM. These results clearly show that a new form of the CYP4F LTB4 omega-hydroxylase exists in human liver.
Department of Food Science and Technology, Faculty of Engineering, Fukuyama University, Hiroshima, Japan.
Y
Y
Kikuta
E
E
Kusunose
T
T
Kondo
S
S
Yamamoto
H
H
Kinoshita
M
M
Kusunose
D000595:Amino Acid Sequence; D001483:Base Sequence; D015152:Blotting, Northern; D003001:Cloning, Molecular; D003577:Cytochrome P-450 Enzyme System / Q000096:biosynthesis / Q000235:genetics*; D000072470:Cytochrome P450 Family 4; D018076:DNA, Complementary; D006801:Humans; D006900:Hydroxylation; D008862:Microsomes, Liver / Q000201:enzymology*; D006899:Mixed Function Oxygenases / Q000096:biosynthesis / Q000235:genetics*; D008969:Molecular Sequence Data; D012441:Saccharomyces cerevisiae
D018076:DNA, Complementary; D003577:Cytochrome P-450 Enzyme System; D006899:Mixed Function Oxygenases; D000072470:Cytochrome P450 Family 4; C040780:leukotriene B4 20-hydroxylase