A Diazotizable Amine Produced by Yeast: its Chemical Nature and Factors Affecting its Accumulation

Abstract
SUMMARY: The effect of area: volume ratio and composition of medium on the accumulation of diazotizable amine (‘amine’) and hypoxanthine yeast 47 growing in biotin-deficient medium are reported. The ‘amine’, isolated from culture filtrates by mercury precipitation and separation on ion exchange resins, gave the Pauly reaction for imidazoles: on acid hydrolysis it yielded ribose, glycine, ammonia and formic acid, but no phosphate. These properties are consistent with the view that the ‘amine’ is 5-amino-imidazole riboside or a closely related compound. When the growth medium contained 500 μg. l-aspartic acid/ml., instead of ‘amine’ and hypoxanthine, substances accumulated which on hydrolysis yielded adenine as the only purine. ‘Amine’ accumulation by yeast 47 may be a symptom of a derangement of purine metabolism resulting from a biotin-conditioned block in aspartate synthesis.