S-adenosyl-L-methionine production by Saccharomyces sake. Optimization of the culture conditions for the production of cells with a high S-adenosyl-L-methionine content.

Abstract

In studies on the production of S-adenosyl-L-methionine (AdoMet) by Saccharomyces sake Kyokai No. 6 in a bench-scale fermentor, the rate of growth of the organism in a medium containing sucrose and urea as carbon and nitrogen sources, respectively, increased with a higher agitation speed (500 rpm) or sucrose feeding, but the cellular content of AdoMet was lower than that with a lower agitation speed (300 rpm) or ethanol feeding. The additin of L-methionine was necessary for enhancement of both growth and AdoMet production. The L-methionine added (15g/1) was efficiently incorporated into the cells during the course of the cultivation, about 20% of the L-methionine being found as AdoMet in the cells. The ultraviolet absorbance (258 nm) based on the extracted AdoMet comprised 73% of the total ultraviolet absorbance of material extracted from the cells, whereas that based on S-adenosylhomocysteine was very low (1.4%).