DAHP SYNTHASE OF PHENYLALANINE NONPRODUCING AND PHENYLALANINE PRODUCING MUTANT STRAINS OF ARTHROBACTER-GLOBIFORMIS

3-Deoxy-D-arabinoheptulosonate 7-P (DAHP) synthase from wild type, try ptophan and tyrosine double auxotrophic mutant and double auxotrophic multianalogue resistant mutant of Arthrobacter globiformis were assaye d. Maximum enzyme activity was observed in late exponential phase and TT-39 PTMN(r)-7 retained maximum activity at late stationary phase of growth. Tryptophan, tyrosine and phenylalanine repressed the enzyme sy nergistically but TT-39 PTMN(r)-7 was less sensitive to repression. Tr yptophan, tyrosine and phenylalanine synergistically inhibited the enz yme but on their own did not produce sufficient inhibition.