PRODUCTION OF 1-PHENYLALANINE BY DOUBLE AUXOTROPHIC MUTANTS OF ARTHROBACTER GLOBIFORMIS - OPTIMIZATION OF C-SOURCE AND N-SOURCE

A number of tryptophan plus tyrosine double auxotrophic mutants isolat ed by NTG treatment of a glutamic acid producing strain of A. globifor mis were found to excrete phenylalanine alone in glucose, ammonium chl oride, mineral salt medium. Among 24 different carbon sources tested g lucose was found to be the best and optimum for 1-phenylalanine produc tion was at 350 mM level. Among 14 different inorganic and organic nit rogen sources tested ammonium chloride was the best and was optimal at 60 mM level for phenylalanine production. On the optimum level of C a nd N sources a yield of 1.5 g/l phenylalanine was achieved.