Abstract
Activities of seven enzymes of the shikimate pathway were compared between the wild-type strain and menaquinone-4-producing mutant strains of Flavobacterium sp. 238-7. Activity of 3-deoxy-D-arabino-heptulosonate-7-phosphate (DAHP) synthase, the first regulatory enzyme in the shikimate pathway, was almost the same in these strains in the stationary phase, but the activity of a sulfonamide-resistant strain, SP0736, was 2 times higher than that of other strains in the logarithmic phase. Shikimate dehydrogenase activity was almost the same among these strains during cultivation. Other enzyme activities of mutants were 1.5-4 fold higher than those of the wild-type strain. DAHP synthase and shikimate kinase were found to be inhibited by chorismate and MK-4. Feedback inhibition for shikimate kinase by chorismate was partially removed in strain SP0736.
