Enzymatic activities of Ura2 and Ura1 proteins (aspartate carbamoyltransferase and dihydro-orotate dehydrogenase) are present in both isolated membranes and cytoplasm of Saccharomyces cerevisiae.
Computational analysis predicted three potential hydrophobic transmembrane alpha-helices within the Ura2 multidomain protein of Saccharomyces cerevisiae, the C-terminal subdomain of which catalyses the second step of uridine-monophosphate biosynthesis by its L-aspartate carbamoyltransferase activity (EC 2.1.3.2). The fourth step of pyrimidine biosynthesis is catalysed by dihydro-orotate dehydrogenase (Ura1 protein; EC 1.3.99.11), which was similarly characterized as a peripheral membrane protein. Ex situ, the activities of the investigated enzymes were associated both with isolated yeast membranes, fractionated by differential centrifugation to remove intact nuclei, and with soluble cytoplasmic proteins.
Vorísek
J
J
Institute of Microbiology, Academy of Sciences of Czech Republic, Vídenská 1083, CZ-14220 Praha 4-Krc, Czech Republic.
Techniková
Z
Z
Schwippel
J
J
Benoist
P
P
D000595:Amino Acid Sequence; D001221:Aspartate Carbamoyltransferase / Q000096:biosynthesis / Q000378:metabolism*; D002223:Carbamoyl-Phosphate Synthase (Glutamine-Hydrolyzing) / Q000096:biosynthesis / Q000378:metabolism*; D002462:Cell Membrane / Q000201:enzymology; D003593:Cytoplasm / Q000201:enzymology; D000090722:Dihydroorotate Dehydrogenase; D005456:Fluorescent Dyes / Q000737:chemistry; D007211:Indoles / Q000737:chemistry; D008969:Molecular Sequence Data; D009097:Multienzyme Complexes / Q000096:biosynthesis / Q000378:metabolism*; D010088:Oxidoreductases / Q000096:biosynthesis / Q000378:metabolism*; D044925:Oxidoreductases Acting on CH-CH Group Donors; D017433:Protein Structure, Secondary; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000502:physiology; D029701:Saccharomyces cerevisiae Proteins
D000090722:Dihydroorotate Dehydrogenase; D005456:Fluorescent Dyes; D007211:Indoles; D009097:Multienzyme Complexes; D029701:Saccharomyces cerevisiae Proteins; C110837:URA2 protein, S cerevisiae; C007293:DAPI; D010088:Oxidoreductases; D044925:Oxidoreductases Acting on CH-CH Group Donors; D001221:Aspartate Carbamoyltransferase; D002223:Carbamoyl-Phosphate Synthase (Glutamine-Hydrolyzing)