GLUCOSE-INDUCED INACTIVATION OF ISOCITRATE LYASE IN ASPERGILLUS-NIDULANS

The existence of a second mechanism of catabolite control of isocitrat e lyase of Aspergillus nidulans, in addition to the carbon catabolite repression phenomenon recently reported was analysed. Isocitrate lyase was rapidly and specifically inactivated by glucose. The inactivation was irreversible at all stages in the presence of cycloheximide, show ing that reactivation depends on de novo protein synthesis. In additio n, analysis of glucose-induced inactivation of isocitrate lyase in a c reA(d)-30 strain showed that the creA gene is not involved in this pro cess.