122 



Perspectives in Microbiology 



Vercellone (14) first reported the reduction of a nuclear 

 double bond or ketone group, as well as oxidation of a 

 nuclear hydroxyl group. This work was confirmed and ex- 



Steroid Nucleus 



tended by many other investigators (36). Turfitt (34) 

 showed that cholestenone (II) could be degraded to etio- 

 cholenic acid (III) as well as isocaproic acid (IV) and the 

 Windaus keto acid (V) by means of a Proactinomyces. 



COOH 



■^ r^^^^\\^ + 



III . CH3-CH2-CH2-CH2-C-OH + 



III 



Etiocholenic Acid 



CH3 



IV 

 Isocaproic Acid 



HOOC 



Windaus Acid 



Kramli and Horvath (12) were the first to report micro- 

 biological oxygenation of a nuclear carbon atom (position 

 7 of the cholesterol (VI) molecule), also by use of a Pro- 

 actinomyceSj to produce 7-hydroxycholesterol (VII). 



VII 

 7 Hydroxycholesterol 



