Abstract
Schlenk et al. reported a convinient production method of S-adenosylmethionine by incubation of yeast in a glucose-salt medium containtng methionine. In this paper the authors studied on the possibility of the formation of DBCC by incubation of yeast in a glucose-salt medium containing hydroxocobalamin with or without methionine, expecting the incorporation of deoxyadenosyl group to the corrin ring in the same manner as in the S-adenosylmethionine formation. Against the expectation the formation of DBCC and the change of the amount of S-adenosylmethionine produced were not observed in the presence of hydroxocobalamin. However unidentified light- and CN^--labile vitamin B_<12>-group compounds were isolated from the incubation supernatant by DEAE-cellulose chromatography. The absorption spectra of these compounds were similar to those of cobamide coenzymes, but they did not exhibit coenzyme activity in Abeles ・ Lee's system. In paperionophoresis one of them showed ananologous behaviors to those of DBCC and the another behaved similarly as vitamin B_<12> coenzyme M of Takeyama and Buchanan. Based on the result of our other experiment in which the methyl analogue of cobamide coenzyme was synthesized from S-adenosylmethionine or S-me-thylmethionine and hydroxocobalamin after reduction with NaBH_4,the formation mechanism of the unidentified compounds, possible relationship to vitamin B_<12> coenzyme M and the hypothetical role in the methionine synthesis were discussed.
