Orotic Acid and Related Compounds in the Nutrition of Lactobacillus bulgaricus 09

Abstract
The orotic acid requirement of Lactobacillus bulgaricus 09 can be met by ureidosuccinic acid (10-20% as active as orotic acid) or by 5-(carboxy-methylidine)-hydantoin (30-40% as active as orotic acid) but not by any one of a large group of related or unrelated compounds studied. The data are taken as micro-biologic evidence that ureidosuccinic acid and possibly ureido-fumaric acid (derived from 5-(carboxy-methylidine)-hydantoin) are precursors of the pyrimidine ring. Data on the distribution of orotic acid in nature are presented.