Phenolic 9,10-secosteroids as products of the catabolism of bile acids by a Pseudomonas sp.

The obligate aerobe, Pseudomonas putida ATCC 31752, efficiently utilises bile acids as a source of carbon and energy for growth and maintenance. When aeration is considerably restricted, a consequence to the catabolism of the bile acids in a fermentor is an accumulation of certain steroidal catabolites. Evidence is presented to show that among these are hydroxy-9,10-seco-1,3,5 (10)-androstratriene-9, 17-diones and those from four of the common bile acids, cholic, chenodeoxycholic, hyodeoxycholic and deoxycholic acids have been isolated and their structures determined. The product of catabolism of hyodeoxycholic acid appears to exist in a hemi-acetal form which readily forms an acetal during isolation procedures. All but one of these are described for the first time.

[Production of the methyl ether of 8,14-seco-delta,3,5,(10),9(11)-estratetraendiol-3,17beta-one-14 using a culture of Saccharomyces cerevisiae BKMU-488]. / Poluchenie metilovogo éfira 8,14-seco-del'tal, 3,5(10),9(11)-éstratetradiola-3,17beta-ona-14 s pomoshch'iu kul'tury Saccharomyces cerevisiae BKMU-488

The culture Saccharomyces cerevisiae BKMU-499 was selected from 100 strains of different Saccharomyces species to obtain an optically active methyl ester 8,14-seco-delta1,3,5(10),9(11)-estratetraendiol-3-17beta-on-14. Various conditions of the transformation were examined. The yield of this keto-alcohol depended on the following factors: level of aeration, method of steroid administration, physiological state of the culture, and composition of the cultivation medium. The optimal yeild of the optically active product was 84%.

Production of 13beta-alkyl-3-methoxy-8,14-seco-1,3,5(10),9(11)-gonatetraen-14beta-ol-17-ones and 13beta-alkyl-3-methoxy-8,14-seco-1,3,5(10),9(11)-gonatetraen-17alpha-ol-14-ones by microbial enzymes.

For the purpose of producing hydroxy-keto-seco-steroids in which hydroxyl group is attached to a carbon atom having the R-configuration, numerous biochemically active microorganisms were tested without any success. The hydroxysteroid oxidoreductase enzymes of the investigated bacterial, yeast and fungal strains were suitable only for the production of 17beta-ol-14-one and 14alpha-ol-17-one derivatives. The required compounds were prepared by combinations of enzymatic reactions with chemical reduction. (i) By hydroxysteroid oxidoreductase of Saccharomyces uvarum and Saccharomyces drosophilarum, 17beta-ol-14-one and 14alpha-ol-17-one derivatives of 14,17-dione, respectively, were obtained. (ii) The above compounds were acetylated then reduced by sodium borohydride. (iii) 14beta,17beta-diol-17-acetate and 14alpha,17alpha-diol-14-acetate were dehydrogenated by dehydroxysteroid oxidoreductase of Nocardia sp. and Mycobacterum sp., respectively, in the presence of steroid esterase. The reaction mixture contained either 14beta-ol-17-one or 17alpha-ol-14-one derivatives, since oxidation by hydroxysteroid oxidoreductase was limited to the hydroxyl group attached to a carbon atom having the S-configuration.