The importance of threonine‐301 from cytochromes P‐450 (laurate (ω‐1)‐hydroxylase and testosterone 16α‐hydroxylase) in substrate binding as demonstrated by site‐directed mutagenesis

FEBS Letters

Nakamura, Masahiko¹  Imai, Yoshio¹ 

[1]Institute for Protein Research, Osaka University, Suita, Osaka 565, Japan

关键词: Cytochrome P-450;    Laurate;    Testosterone;    Hydroxylation;    Site-directed mutagenesis;    P-450;    cytochrome P-450;    P450(ω-1);    P-450 (laurate (ω-1)-hydroxylase);    P-450(16α);    P-450 (testosterone 16α-hydroxylase);    P-450SG1;    P-450 from a yeast mutant defective in lanosterol 14α-demethylation;    P-450cam;    Pseudomonas putida P-450;   

DOI  :  10.1016/0014-5793(88)80106-6

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Threonine-301 from rabbit liver cytochromes P-450 (laurate (ω-1)-hydroxylase and testosterone 16α-hydroxylase) has been replaced by histidine via site-directed mutagenesis. In the oxidized state the mutant P-450s exhibited typical low-spin type absorption spectra of P-450 and their reduced CO complexes showed a Soret peak at 450 nm. However, no spectral change was induced on addition of substrates for their wild-type counterparts. The mutant P-450s were also completely devoid of the hydroxylase activity. These findings suggest that threonine-301, which is highly conserved in P-450s and located at the distal heme surface, plays an important role in substrate binding.

【 授权许可】

Unknown