STEROL SIDE CHAIN-CLEAVING ENZYME PROTEIN AND USE THEREOF

摘要

P450scc enzyme protein is an important enzyme protein which can catalyze the first stage in an industrially useful steroid hormone biosynthesis. The invention aims to obtain P450scc enzyme protein having a high activity. Specifically disclosed is a sterol side chain-cleaving enzyme protein having the following physicochemical properties (1) and (2): (1) activity: the enzyme protein can act on a sterol represented by formula (I) defined in the description to cleave the bond between a carbon at position-20 and a carbon at position-22 in the sterol side chain moiety in the sterol, thereby producing a compound represented by formula (II) defined in the description; and (2) substrate specificity: when a microorganism capable of producing the enzyme protein is reacted in an aqueous solution containing 100 µg/ml of 4-cholesten-3-one or cholesterol at 28°C for 5 hours, the rate of conversion reaction from 4-cholesten-3-one into progesterone is 10% or more and the rate of conversion from cholesterol into pregnenolone is 10% or more.