The Purine Requirement of Staphylococcus flavocyaneus

Abstract

The requirement of Staphylococcus flavocyaneus for a purine is met by adenine, hypoxanthine, their ribo-sides and ribotides, 4-amino-5-imidazolecarboxamide or 4-amino-5-imidazolecarboxamidine. Hypoxanthine, adenosine and inosine are effective in amounts smaller than those of adenine or the ribotides. The effective purines are inhibited by guanine or its analogues, and this inhibition can be overcome by adenosine or adenylic acid, but not p-aminobenzoic acid, folic acid, the other B vitamins, or amino acids. These experiments support the hypothesis that the unnatural purines divert pentose from synthetic pathways, and thus interfere with nucleic acid synthesis.