Inter-relationships of Serine, Glycine and Vitamin B6 in the Growth of Mutants of Escherichia coli

Abstract

SUMMARY: Five mutants of Escherichia coli which grow to a greater or less extent when the minimal medium is supplemented with vitamin B6 have been studied. They fall into two groups according to the further effect of serine + glycine on growth. (1) Two strains showed full and rapid growth with pyridoxine alone and serine + glycine neither replaced this vitamin nor enhanced growth in its presence. (2) Three strains showed delayed and suboptimal growth with pyridoxine alone. With these serine + glycine had two effects: (a) it decreased the lag and enhanced the final extent of growth when added with pyridoxine; (b) it permitted suboptimal growth in the absence of pyridoxine. The second effect was dependent on (two strains), or greatly increased by (one strain), the concurrent addition of glycolaldehyde.