The present paper describes the biosynthesis of the thiamin thiazole in Bacillus subtilis and Saccharomyces cerevisiae. The two pathways are quite different: in B. subtilis, the thiazole is formed by an oxidative condensation of glycine, deoxy-D-xylulose 5-phosphate and a protein thiocarboxylate, whereas, in S. cerevisiae, the thiazole is assembled from glycine, NAD and Cys205 of the thiazole s...

A rapid (6-7 hr), modified Kirby-Bauer disk-susceptibility method, by which derivatives of tetrazolium dyes are used to enhance delineation between areas of growth and zones of inhibition, has been developed. Inoculated petri plates, prepared by the Kirby-Bauer method, were sprayed, after 6 to 7 hr of incubation (37 C), with aqueous solutions of MTT-tetrazolium or INT-tetrazolium resulting in r...