The pantothenic acid content of coenzyme A by chick assay.

Lipmann, Kaplan, Novelli, Tuttle, and Guirard (1) reported that, whereas concentrates of the coenzyme required for acetylation (coenzyme A) showed no pantothenic acid activity by the ordinary microbiological assay, considerable amounts of p-alanine were found after acid hydrolysis. From this early observation, it was suspected that the coenzyme might contain combined pantothenic acid which was unavailable to Lactobacillus casti. If such were the case, it seemed likely that chicks or other animals would be able to utilize this pantothenic acid; the animal would presumably have the mechanism for both the decomposition to, and the synthesis from, the constituent parts. An early trial yielded promising results, but, before sufficient material was available for adequate study, the above authors clearly demonstrated by other means that pantothenic acid was a constituent of the coenzyme (1). Lipmann, Kaplan, and Novelli (2) have shown that the pantothenic acid appears to be bound by two linkages, one of which is to phosphate, as is indicated by the activity of phosphodiesterase in liberating phosphate with simultaneous loss of coenzyme activity. Both linkages are essential for activity and both must be split before the pantothenic acid becomes “free” when tested by microbiological assay. This is accomplished by intestinal phosphatase and a pigeon liver enzyme together. It was of considerable interest therefore to determine the availability of the pantothenic acid in coenzyme preparations for the chick, since it now appears that much of the pantothenic acid in certain foods is present as the coenzyme. We have compared the potency of two preparations when administered both orally and intraperitoneally. For comparative purpose the activity of calcium pantothenate given by these two routes was determined.