PANTOTHENIC ACID STUDIES VIII. (PAC)

Abstract

A pantothenic acid conjugate (PAC) was found to exert growth promoting activity superior to that of the free vitamin in Acetobacter suboxydans, Escherichia coli, and Aerobacter aerogenes. PAC is not utilized at all as a pantothenic acid source by the lactic acid bacteria, including Leuconostoc mesenteroides 694, 8042, or P-60 (Dunn); Lactobacillus gayoni 8289; L. delbruckii 3; L. arabinosus 17-5; L. acidophilus (two unidentified strains); L. brevis 118-8 or L-35; and Streptococcus fecalis R. PAC is more effective than pantothenic acid in reversing the inhibitory effect of alpha-hydroxy-beta, beta-dimethylbutyryltaurine, which inhibits the utilization of pantothenic acid in A. suboxydans. When used with E. coli and A. aerogenes to counteract inhibitors (2-chloro-4-amino-benzoic acid or salicylic acid), which do not directly affect the utilization of pantothenic acid, PAC is similar in its action to the free vitamin. It is concluded that PAC is one of the functional derivatives of pantothenic acid in these organisms.