Functional modulation of a peroxygenase cytochrome P450: novel insight into the mechanisms of peroxygenase and peroxidase enzymes

FEBS Letters

Matsunaga, Isamu¹  Ogura, Hisashi¹  Sumimoto, Tatsuo²  Ayata, Minoru¹ 

[1] Department of Virology, Osaka City University Medical School, 1-4-3 Asahi-machi, Abeno-ku, Osaka 545-8585, Japan;Osaka Prefectural Institute of Public Health, 1-3-69 Nakamichi, Higasinari-ku, Osaka 537-0025, Japan

关键词: Cytochrome P450;    Fatty acid;    Peroxygenase;    Peroxidase;    CPO;    chloroperoxidase;    HRP;    horseradish peroxidase;    P450;    cytochrome P450;    P450BSβ;    fatty acid α- or β-hydroxylating-cytochrome P450 from Bacillus subtilis;    TMB;    3;    5;    3′;    5′-tetramethylbenzidine;   

DOI  :  10.1016/S0014-5793(02)03261-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Cytochrome P450_BSβ is a peroxygenase that catalyzes the α- or β-hydroxylation of myristic acid by utilizing H₂O₂. The wild-type enzyme not only hydroxylated myristic acid, but oxidized 3,5,3′,5′-tetramethylbenzidine (TMB), a peroxidase substrate, in a myristic acid-dependent reaction. Study of inhibition of hydroxylation of myristic acid by TMB indicates these two substrates compete for the same highly reactive intermediate during the course of their respective reactions. When deuterated myristic acid was used as a substrate to decrease hydroxylation activity, the rate of TMB oxidation increased. This increased rate of TMB oxidation was greatly enhanced when the R242K mutant enzyme bound with deuterated myristic acid was used. These results suggest that there are critical structural elements at the distal active site which determine whether this enzyme acts as a peroxygenase or a peroxidase.

【 授权许可】

Unknown