Pyridoxine is a precursor of the pyrimidine moiety of thiamin in Saccharomyces cerevisiae.
We studied the origin of the N-1 atom of the pyrimidine moiety of thiamin in a eucaryote, Saccharomyces cerevisiae. The competitive effects of 14N-compounds on the incorporation of 15N-NH4Cl into the pyrimidine moiety were examined. Amino acids, the bases of nucleic acids and glucosamine did not decrease 15N incorporation, but pyridoxine did. We conclude that the N-atom of pyridoxine is the origin of the N-1 atom of the pyrimidine of thiamin synthesized by S. cerevisiae. We also suggest that the N-atom of pyridoxine is derived from glutamine.
Tazuya
K
K
Faculty of Pharmaceutical Sciences, Mukogawa Women's University, Hyogo, Japan.
Yamada
K
K
Kumaoka
H
H
D000596:Amino Acids / Q000378:metabolism / Q000494:pharmacology; D000643:Ammonium Chloride / Q000378:metabolism; D008401:Gas Chromatography-Mass Spectrometry; D005944:Glucosamine / Q000378:metabolism / Q000494:pharmacology; D011687:Purines / Q000378:metabolism / Q000494:pharmacology; D011736:Pyridoxine / Q000737:chemistry / Q000378:metabolism*; D011743:Pyrimidines / Q000378:metabolism / Q000494:pharmacology; D012441:Saccharomyces cerevisiae / Q000254:growth & development / Q000378:metabolism*; D013831:Thiamine / Q000096:biosynthesis* / Q000737:chemistry
D000596:Amino Acids; D011687:Purines; D011743:Pyrimidines; D000643:Ammonium Chloride; D011736:Pyridoxine; D005944:Glucosamine; D013831:Thiamine