Transient Effect of Exogenous Adenine on Germination of Asrergillus Oryzae Conidia

Abstract

Aspergillus oryzae conidia germinate with good synchrony in a modified Czapek's medium supplemented with L-alanine and adenine. The present report deals with the role of adenine in the process of germination.Exogenous adenine is required only transiently during a period of 40-90 min after inoculation.14C-Adenine incorporation experiments showed that inosine, AMP, ATP, and NAD comprised nearly 90% of radioactivity in the acid-soluble fraction.Incorporation of 14C-adenine into RNA was accelerated markedly in this transient period. The rate of subsequent protein synthesis was retarded if adenine was not added during the transient period.The present data suggest that the exogenous adenine serves as one of the initiation factors for vegetative growth but not as a trigger for germination.