Abstract
This work was designed to obtain a microbial mutant suitable for the industrial production of uridine. The growth of a wild type strain of Bacillus subtilis was inhibited by uracil analogs, such as 2-thiouracil and 6-azauracil, and the inhibition was reversed by adding uracil. Mutants resistant to these analogs were isolated. Among them, strain No. 508 produced 46 mg/ml of uridine; however, 6mg/ml of uracil was accumulated concomitantly. When this strain was subjected to further mutation to obtain mutants deficient in uridine phosphorylase activity, another mutant, No. 556, was obtained that produced 55 mg/ml of uridine with no appreciable amount of uracil.
