Catabolite repression of the synthesis of inducible polygalacturonase and pectinesterase by Aspergillus niger sp.

Abstract

The synthesis of pectinesterase (PE) and polygalacturonase (PG) by a strain of Aspergillus niger isolated from rotten lemons was repressed by glucose, even in the presence of the inducer. The production of both enzymes started again once the sugar was used up, or when the mycelium was washed free of glucose and incubated in a glucose-free medium containing the inducer; this proved the reversibility of the repression mechanism. The effect of glucose was also tested in the absence of transcription. The results obtained suggest that repression occurs at the translational level. © 1989 Springer-Verlag New York Inc.