1-Ene-steroid reductase of Mycobacterium sp. NRRL B-3805.
The microbial enzymatic reduction of 1,4-androstadiene-3,17-dione (ADD) to 4-androstene-3,17-dione (AD), testosterone and 1-dehydrotestosterone (DHT) is described. Two reducing activities observed in washed cell suspensions and cell free extracts of Mycobacterium sp. NRRL B-3805 were found to account for these bioconversions. One was a 1-ene-steroid reductase and the other a 17-keto steroid reductase. The first reducing activity was found to appear in the soluble cell fraction whereas the latter could be precipitated by centrifugation. Maximum 1-ene-steroid reductase specific activity was achieved during the exponential growth phase of the organism and significantly increased upon induction with ADD. The 1-ene-steroid reductase was partially purified (30-fold) by ammonium sulfate fractionation, gel-filtration and ion-exchange chromatography, and was eluted from a Sephacryl S-300 column with an Mr = 115,000. The 1-ene-steroid reductase activity was NADPH-dependent and had specificity towards steroid compounds containing C-1,2 double bond with an apparent Km for ADD of 2.2 X 10(-5) M. The reverse reaction catalyzing C-1,2 dehydrogenation could not be detected in our preparations. The results suggest that in Mycobacterium sp NRRL B-3805 and B-3683 the steroid C-1,2 dehydrogenation and 1-ene reduction are two separable activities.
D015067:17-Hydroxysteroid Dehydrogenases / Q000378:metabolism; D000730:Androstadienes / Q000378:metabolism; D000734:Androstenediols / Q000378:metabolism; D003600:Cytosol / Q000201:enzymology; D009154:Mutation; D009161:Mycobacterium / Q000201:enzymology* / Q000235:genetics; D010088:Oxidoreductases / Q000302:isolation & purification / Q000378:metabolism*; D013379:Substrate Specificity; D013739:Testosterone / Q000031:analogs & derivatives / Q000378:metabolism
D000730:Androstadienes; D000734:Androstenediols; C021287:4-androstene-3,17-diol; C006573:1,4-androstadiene-3,17-dione; D013739:Testosterone; C013915:boldenone; D010088:Oxidoreductases; D015067:17-Hydroxysteroid Dehydrogenases; C040071:1-ene-steroid reductase