Effect of Sulfur-containing Amino Acids on the Production of Thiamine by Escherichia Coli.

It has now been firmly established by several groups of workers (1-10) that in yeast thiamine is enzymatically synthesized from pyrimidine pyrophosphate and thiazole monophosphate. However, there is little information about the biosynthetic pathways of pyrimidine and thiazole themselves. Thiamine was found as the first natural com pound containing a thiazole ring. Recently, the presence of the thiazole ring system has been demonstrated in luciferin (11) and in antibiotics, such as micrococcin P (12, 13), bottromycin (14), thiostrepton (15, 16), and bacitracin F (17). Chemical structure similar to the thiazole ring system has been found in bacitracin A (18). It was indicated clearly that they were derived from polypeptides containing cysteine and by cyclization to a thiazoline for bacitracin A and by cyclization followed by de hydrogenation to thiazole rings for the others. The chemical structure of penicillin in which the thiazolidine ring is a dipeptide composed of a cysteine derivative and valine. It has been established that C14-, S35-, and H3-labelled cysteine gave rise to labelled penicillin (19-21). It is considered that the thiazole ring of thiamine is also syn thesized via sulfur-containing amino acid. Such concepts were already presented by several workers without reliable data (22-25). A detailed study was made on the effect of sulfur-containing amino acids and other amino acids on the production of thiamine by Escherichia coli.