Open AccessFunctional expression of the cDNAs encoding rat 11β‐hydroxylase [cytochrome P 450(11β)] and aldosterone synthase [cytochrome P 450(11β, aldo )]
Author(s) -
AKA Yasuki,
OKAMOTO Mitsuhiro
Publication year - 1991
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1991.tb16449.x
Subject(s) - hydroxylation , cytochrome p450 , aldosterone , cytochrome , corticosterone , chemistry , aldosterone synthase , beta (programming language) , steroid 11 beta hydroxylase , medicine , endocrinology , enzyme , biology , microbiology and biotechnology , biochemistry , steroid , renin–angiotensin system , hormone , blood pressure , computer science , programming language
Expression plasmids containing two cDNAs of a rat cytochrome P 450(11β) family, pc P 450(11β)‐62 [Nonaka, Y., Matsukawa, N., Morohashi, K., Omura, T., Ogihara, T., Teraoka, H. & Okamoto, M. (1989) FEBS Lett. 255 , 21–26] and pc P 450(11β, aldo)‐46 [Matsukawa, N., Nonaka, Y., Ying, Z., Higaki, J., Ogihara, T. & Okamoto, M. (1990) Biochem. Biophys. Res. Commun. 169 , 245–252], were constructed and introduced into COS‐7 cells by electroporation. Enzymatic activities of the expressed cytochromes P 450(11β) and P 450(11β, aldo) were determined by using 11‐deoxycorticosterone, corticosterone, 18‐hydroxy‐11‐deoxycorticosterone, 18‐hydroxycorticosterone, or 19‐hydroxy‐11‐deoxycorticosterone as a substrate. Cytochrome P 450(11β) catalyzed 11β‐, 18‐and 19‐hydroxylations of 11‐deoxycorticosterone and 19‐oxidation or 19‐hydroxy‐11‐deoxycorticosterone at substantial rates, 18‐hydroxylation of corticosterone at a very low rate, but no aldosterone production. Cytochrome P 450(11β, aldo) catalyzed 11β‐ and 18‐hydroxylations of 11‐deoxycorticosterone, 18‐hydroxylation of corticosterone and aldosterone production from 11‐deoxycorticosterone or corticosterone. But neither 19‐hydroxylation of 11‐deoxycorticosterone nor 19‐oxidation of 19‐hydroxy‐11‐deoxycorticosterone was catalyzed by cytochrome P 450(11β, aldo).