The Bacterial Synthesis of Biotin in Animals

In the rumen of the calf (51) as well as that of the cow (98) biotin was found to be synthesized in considerable amounts. The rumen contents sampled four hours after feeding showed about five times the value of biotin as compared to that of the feed (51). 

Rats have been shown to thrive well on a biotin-free diet. However, when sulfaguanidine or succinylsulfathiazole is incorporated in such a diet (44-46) a deficiency develops which can be prevented or cured by the 

The synthesis of inositol by the bacterial fiora of the mouse has been definitely established by Woolley (111). Cultures of the intestinal contents of the mouse in a synthetic medium, showed that the intestinal organisms were capable of synthesizing the vitamin. This phenomenon furnished adequate explanation to the observation (112) that deficient mice with alopecia exhibited spontaneous cures while subsisting on an inositol-free regime (113). The amount of the vitamin stored was found to be lower in the bodies of mice with alopecia as compared with that stored by mice showing spontaneous cures. Moreover, the bacterial flora of the former showed poor synthesis as compared with the latter, when such flora was grown in synthetic media. 

The bacteria that have been shown to syntherize inositol in a vitamin-free medium are Aerobacter aerogenes. Pseudomonas fluorescens, Proteus vulgaris, dostridium butylicum (65). 

The definite influence of the dietary intake on the intestinal flora of widely separated species was clearly demonstrated by Herter and Kendall 

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