Relationship between Aconitate Hydratase Activity and Citric Acid Productivity in Fluoroacetate-sensitive Mutant Strain of Candida lipolytica

Abstract

Fluoroacetate-sensitive mutant strains, K–20 and S–22, of Candida lipolytica could not grow or could only slightly grow on agar media containing di- or tricarboxylic acid involved in the TCA-cycle as the sole source of carbon. Relative activities of aconitate hydratase in the cells of the mutant strains, K-20 and S-22, were approximately 1/10 and 1/100, against that of the parent strain, respectively. This facts support the statement that the mutant strains were extremely sensitive to monofiuoroacetate.The aconitate hydratase activities of these mutant strains and the parent strain corresponded well to the citric to (+)-isocitric acid ratio in the final fermented broths.