Thiamin Biosynthesis in Yeast. Origin of the Five-Carbon Unit of the Thiazole Moiety

Article abstract of DOI:10.1021/ja00382a033

Radioactivity from D-<1-14C>-, D-<2-14C>-, and D-<6-14C>glucose, from D-<1-14C>fructose, and from <1-14C>glycerol is incorporated nonrandomly into the C₅ chain of the thiazole moiety of thiamin in Saccharomyces cerevisiae.The incorporation pattern leads to inference that the C₅ chain is derived from a 2-pentulose, which is generated from the hexose precursors by the oxidative as well as by the nonoxidative pentose phosphate pathway.A chemically rational scheme for the biogenesis of the thiazole moiety of thiamin is presented.