STUDIES ON COCARBOXYLASE BIOSYNTHESIS BY YEAST

Abstract

Sodium-fluoride inhibits, as is well known, the biosynthesis of cocarboxylase by yeast. By careful study of the process of inhibition, we have succeeded in explaining the pathways prevailing in the synthesis of cocarboxylase in yeast. In bakers' yeast cocarboxylase is biosynthesized from thiamine and ATP by phosphorylation with the aid of thiaminokinase. On the other hand ATP, which is produced from phospho-enol-pyruvic acid, appearing in the process of glycolysis, proves to be an important source of phosphate in the mechanism of thiamine phosphorylation, and the mechanism of cocarboxylase biosynthesis by yeast from phospho-enolpyruvic acid is proved to be the same as by animal tissue.