Regulation of one carbon biosynthesis and utilization in Escherichia coli

Abstract

The regulation of several enzymes involved in one carbon metabolism was studied in a mutant of E. coli K 12 defective in S adenosylmethionine synthetase. The mutant that was reported to have a low endogenous concentration of S adenosylmethionine had elevated levels of N 5,10 methylene tetrahydrofolate dehydrogenase was not altered. These results suggest that S adenosylmethionine plays a role in the regulation of one carbon production and utilization. An enzyme system that cleaved glycine to one carbon units was demonstrated. The enzymes responsible for the cleavage of glycine were induced by exogenous glycine but were independent of S adenosylmethionine or purine levels in the cell.