title: Divergent evolution of pyrimidine biosynthesis between anaerobic and aerobic yeasts.
abstract: A cDNA encoding the dihydroorotate dehydrogenase (DHOdehase; EC 1.3.3.1) of the yeast Schizosaccharomyces pombe was isolated by functional complementation in Saccharomyces cerevisiae. A divergent subcellular compartmentation of the DHOdehase of each yeast was shown. The DHOdehase from Sch. pombe was localized in the mitochondria whereas its homolog from S. cerevisiae was found to be cytosolic. The heterologous expression of the Sch. pombe enzyme in S. cerevisiae allowed us to demonstrate that the Sch. pombe DHOdehase activity requires the integrity of the mitochondrial electron transport chain. Indeed, the presence of a mutation inactivating cytochrome b abolished the complementation of a S. cerevisiae ura1 mutant by the corresponding Sch. pombe gene. By contrast, in vitro studies have revealed that the DHOdehase of S. cerevisiae uses fumarate as terminal electron acceptor. These results are discussed in relation to the anaerobic growth competence of the two yeasts and to the fermentative processes they use.
authors.affiliation: Laboratoire d'Enzymologie, Centre National de la Recherche Scientifique, Gif-sur-Yvette, France.
authors.forename: M
authors.initials: M
authors.lastname: Nagy
authors.forename: F
authors.initials: F
authors.lastname: Lacroute
authors.forename: D
authors.initials: D
authors.lastname: Thomas
mesh_terms: D000332:Aerobiosis; D000595:Amino Acid Sequence; D000693:Anaerobiosis; D000818:Animals; D001483:Base Sequence; D005075:Biological Evolution; D004271:DNA, Fungal / Q000235:genetics / Q000302:isolation & purification; D000090722:Dihydroorotate Dehydrogenase; D004331:Drosophila melanogaster / Q000201:enzymology / Q000235:genetics; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D017353:Gene Deletion; D005800:Genes, Fungal; D007700:Kinetics; D008969:Molecular Sequence Data; D010088:Oxidoreductases / Q000235:genetics* / Q000378:metabolism; D044925:Oxidoreductases Acting on CH-CH Group Donors; D011743:Pyrimidines / Q000096:biosynthesis*; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism; D012568:Schizosaccharomyces / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D013347:Subcellular Fractions / Q000201:enzymology
chemical_list: D004271:DNA, Fungal; D000090722:Dihydroorotate Dehydrogenase; D011743:Pyrimidines; D010088:Oxidoreductases; D044925:Oxidoreductases Acting on CH-CH Group Donors