STUDIES ON CONVERSION OF AMINO ACID FERMENTATION IN AEROBACTER AEROGENES NO 19-35 .I. EFFECT OF PURINE AND PYRIMIDINE ANALOGUES ON GROWTH AND AMINO ACID ACCUMULATION

Effects of purine and pyrimidine analogues on growth and amino acid accumulation were studied using Aerobacter aerogenes No. 19–35 which produces l-valine in phosphate-rich medium (PS-medium) and l-glutamic acid in phosphate-poor medium (PD-medium). The cell growth was inhibited in PS-medium containing purine and pyrimidine analogues. In PD-medium, 6-thiolpurine such as 6-mercaptopurine, 6-methylmercaptopurine and 6-thioguanine did not inhibit cell growth while other drugs did. The addition of 6-thiol-purine, especially 6-mercaptopurine, to PD-medium provoked the production of valine in place of l-glutamic acid. Cells are classified into two types by these characters: l-valine producing type and l-glutamic acid producing type. Such conversion phenomena seemed to occur only in strain No. 19–35, since other strains of A. aerogenes and E. coli producing valine did not show the conversion phenomenon when exposed to 6-thiolpurines. © 1961 Taylor & Francis Group, LLC.