Citrate regulation of the change in carbohydrate degradation during the initial phase of the citric acid production by Aspergillus niger

Abstract

A change from pentose phosphate pathway to glycolysis has been shown to occur in the early stages of Aspergillus niger growth in a high citric acid yielding medium. The decrease of pentose phosphate metabolism was shown to be due to inhibition of 6-phosphogluconate dehydrogenase by intracellular citrate. The regulatory enzyme of glycolysis, 6-phosphofructokinase, whose activity could not be detected immediately after spore germination, showed a progressive increase in activity thereafter.