THE ROLE OF ANTHRANILIC ACID IN THE NUTRITION OF LACTOBACILLUS ARABINOSUS

Abstract

Of 19 possible intermediates in the pathway of indole synthesis from anthranilic acid, none supports growth of L. arabinosus, strain 17-5. Glucose, acetate, and coenzyme A play significant roles in the utilization of anthranilic acid by resting cells of this organism; indole is not formed under these conditions. Indole utilization also requires glucose, and in addition, serine and pyridoxal phosphate; tryptophan, however, is not formed. Growth of this organism in media containing anthranilic acid or indole in place of tryptophan yields cells with significantly low trypto-phan levels in cellular material, suggesting that these nutritional substituents are not converted to tryptophan but to another substance replacing tryptophan in the cell. These data indicate that the pathway of tryptophan synthesis described in the mold Neurospora is not present in L. arabinosus.