title: Production of a precursor to the pyrimidine moiety of thiamine.
abstract: The supernatant fluid from cultures of Escherichia coli W-11, a pur E mutant, prevented the inhibition of growth of E. coli B in a medium containing adenine or adenosine. Adenine inhibition was prevented more readily than adenosine inhibition. More than 90% of the biological activity of the supernatant fluid was recovered in the anionic fraction after treatment with Dowex-50 (NH4+). The cationic fraction, containing large amounts of 5-aminoimidazole ribonucleoside (AIRS), did not prevent adenine inhibition. The W-11 supernatant fluid was shown by bioautography to contain only one compound that prevented adenine inhibition. Proliferating and non-proliferating cultures produced only one compound that prevented adenine inhibition. The compound was shown to be an intermediate (int-1) in the biosynthesis of the pyrimidine moiety of thiamine, Int-1 was stable during sterilization at 121 C for 15 min, during concentration by either flask evaporation or lyophilization, and after storage for  several days at 4 C or at -- 20 C. Int-1 was distinguishable from other known derivatives or intermediates of the pyrimidine moiety. A scheme is presented that illustrates the proposed relationship between int-1 and the synthesis of thiamine.
mesh_terms: D000225:Adenine / Q000494:pharmacology; D000241:Adenosine / Q000494:pharmacology; D004355:Drug Stability; D004754:Enterobacter / Q000254:growth & development / Q000378:metabolism; D004926:Escherichia coli / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D007093:Imidazoles; D009154:Mutation; D011743:Pyrimidines / Q000096:biosynthesis* / Q000378:metabolism; D012263:Ribonucleosides / Q000096:biosynthesis; D012486:Salmonella typhimurium / Q000254:growth & development / Q000378:metabolism; D013696:Temperature; D013831:Thiamine / Q000096:biosynthesis* / Q000378:metabolism; D013835:Thiamine Pyrophosphate / Q000378:metabolism
chemical_list: D007093:Imidazoles; D011743:Pyrimidines; D012263:Ribonucleosides; D000225:Adenine; D000241:Adenosine; D013835:Thiamine Pyrophosphate; D013831:Thiamine