EFFECT OF ALANINE AND THREONINE ON THE SYNTHESIS OF SERINE BY LEUCONOSTOC MESENTEROIDES

Abstract

Varying the glycine concentration when L-alanine was present suggested a direct relationship between the molar ratio of these two amino acids and the amount of growth achieved by the test organism. Supplements of leucovorin did not reverse the effect of L-alanine upon growth. In experiments with washed cells of L. mesenteroides, both L-alanine and L-threonine reduced the amount of C14labeled formate fixed into serine and the amount of glycine-1-C'4 found in boiling-water extracts of the cells. Neither L-alanine nor L-threonine had any inhibitory effect upon the glycinedependent disappearance of formaldehyde by acetone powders prepared from L. mesenteroides.