Conjugation of tomatine with l(+)-lactic acid by Nocardia restricta

✍ Scribed by Doc. Dr. R. Komel; M. Karlovšek

• Book ID: 102387029
• Publisher: John Wiley and Sons
• Year: 1985
• Tongue: English
• Weight: 486 KB
• Volume: 25
• Category: Article
• ISSN: 0233-111X
• DOI: 10.1002/jobm.3620250707

✦ Synopsis

Nocardicz restricta conjugates tomatines with L( +)-lactic acid, which represents a new mode of bioconversion of steroid glycosides. The specifity in cell-free homogenate was not restricted to cu-tomatine, since d-tomatine was transformed to the conjugated metabolite as well. It was shown with inhibitors of protein synthesis that the enzymes responsible for this reaction are constitutive. By using protoplasts and centrifugation i t was found that the conjugating activity and the reaction products were bound to the membrane part of the 10,000 x g sediment of the cell-free homogenate. Possible mechanisms as well as the biological significance of this reaction are discussed.

Microbial bioconversions of steroids are an important tool in solving problems of organic synthesis of biologically active conipounds as well as in elucidating different problems in biochemical investigations. I n this context steroid alkaloids are of interest as well, partially because of their pharmacological properties (TRUHAUT et al. 1967,