title: Incorporation of histidine into the pyrimidine moiety of thiamin in Saccharomyces cerevisiae.
abstract: To investigate the incorporation of histidine into the pyrimidine moiety of thiamin in eukaryotes, Saccharomyces cerevisiae was grown in a synthetic medium in the presence of 15N- or 14C-labeled histidine. Two 15N-atoms of DL-[1,3-15N2]histidine were incorporated into the N-3 and amino-N atom at C-4 of pyrimidine. Furthermore, incorporation of the 15N-amino group of aspartate, the origin of the N-1 of histidine, into the N-3 of pyrimidine shows that N-3 and the amino-N atom at C-4 of pyrimidine are derived from N-1 and N-3 of histidine, respectively. In contrast, the 15N atom of DL-[amino-15N]histidine was not incorporated into the molecule, whereas L-[2-14C]histidine was incorporated directly into the pyrimidine. We conclude that N-1, C-2, and N-3 of histidine are the origins of the N-3, C-4, and amino-N at C-4 of the pyrimidine in thiamin synthesized by S. cerevisiae.
authors.affiliation: Faculty of Pharmaceutical Sciences, Mukogawa Women's University, Hyogo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Tazuya
authors.forename: K
authors.initials: K
authors.lastname: Yamada
authors.forename: H
authors.initials: H
authors.lastname: Kumaoka
mesh_terms: D001224:Aspartic Acid / Q000378:metabolism; D002250:Carbon Radioisotopes; D055598:Chemical Phenomena; D002621:Chemistry; D006639:Histidine / Q000378:metabolism*; D013058:Mass Spectrometry; D009590:Nitrogen Radioisotopes; D011743:Pyrimidines / Q000096:biosynthesis*; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D013831:Thiamine / Q000096:biosynthesis*
chemical_list: D002250:Carbon Radioisotopes; D009590:Nitrogen Radioisotopes; D011743:Pyrimidines; D001224:Aspartic Acid; D006639:Histidine; C030986:pyrimidine; D013831:Thiamine