Ogishima T, Mitani F, Ishimura Y
Department of Biochemistry, School of Medicine, Keio University, Tokyo.
J Biochem. 1989 Apr;105(4):497-9. doi: 10.1093/oxfordjournals.jbchem.a122694.
Two distinct forms of cytochrome P-45011 beta, with apparent molecular weights of 48,500 (48.5K) and 49,500 (49.5K), have been isolated from bovine adrenocortical mitochondria. Their amino acid sequences up to the 19th position from the N-terminus were only different at the 6th position (Val and Ala for the 48.5K and 49.5K enzymes, respectively). Each sequence was assignable to a distinct cDNA clone for cytochrome P-450(11) beta (Kirita, S., et al. [1988] J. Biochem. 104, 683-686), indicating that the two proteins originate from different genes in bovine adrenocortical cells. Both forms of cytochrome P-450(11) beta were capable of catalyzing aldosterone synthesis as well as the 11 beta- and 18-hydroxylation of 11-deoxycorticosterone. Thus, at least two distinct cytochrome P-450(11) beta species exist in the adrenal cortex and participate in steroidogenesis.
已从牛肾上腺皮质线粒体中分离出两种不同形式的细胞色素P - 45011β，其表观分子量分别为48,500（48.5K）和49,500（49.5K）。它们从N端起至第19位的氨基酸序列仅在第6位不同（48.5K和49.5K酶分别为缬氨酸和丙氨酸）。每个序列都可对应于细胞色素P - 450(11)β的一个不同的cDNA克隆（Kirita, S.,等人[1988]《生物化学杂志》104, 683 - 686），这表明这两种蛋白质源自牛肾上腺皮质细胞中的不同基因。两种形式的细胞色素P - 450(11)β都能够催化醛固酮的合成以及11 - 脱氧皮质酮的11β - 和18 - 羟化反应。因此，肾上腺皮质中至少存在两种不同的细胞色素P - 450(11)β同工型，并参与类固醇生成。
