Uridine 5'-polyphosphates (p4U and p5U) and uridine(5')polyphospho(5')nucleosides (Up(n)Ns) can be synthesized by UTP:glucose-1-phosphate uridylyltransferase from Saccharomyces cerevisiae.
UTP:glucose-1-phosphate uridylyltransferase (EC 2.7.7.9) from Saccharomyces cerevisiae can transfer the uridylyl moiety from UDP-glucose onto tripolyphosphate (P(3)), tetrapolyphosphate (P(4)), nucleoside triphosphates (p(3)Ns) and nucleoside 5'-polyphosphates (p(4)Ns) forming uridine 5'-tetraphosphate (p(4)U), uridine 5'-pentaphosphate (p(5)U) and dinucleotides, such as Ap(4)U, Cp(4)U, Gp(4)U, Up(4)U, Ap(5)U and Gp(5)U. Unlike UDP-glucose, UDP-galactose was not a UMP donor and ADP was not a UMP acceptor. This is the first example of an enzyme that may be responsible for accumulation of dinucleoside tetraphosphates containing two pyrimidine nucleosides in vivo. Occurrence of such dinucleotides in S. cerevisiae and Escherichia coli has been previously reported (Coste et al., J. Biol. Chem. 262 (1987) 12096-12103).
Guranowski
Andrzej
A
Departamento de Bioquímica, Instituto de Investigaciones Biomédicas Alberto Sols, UAM/CSIC, Facultad de Medicina, c. Arzobispo Morcillo 4, 28029 Madrid, Spain. guranow@au.poznan.pl
de Diego
Anabel
A
Sillero
Antonio
A
Günther Sillero
María Antonia
MA
D015226:Dinucleoside Phosphates / Q000096:biosynthesis*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*; D005957:UTP-Glucose-1-Phosphate Uridylyltransferase / Q000378:metabolism*; D014500:Uracil Nucleotides / Q000096:biosynthesis*; D014531:Uridine Diphosphate Galactose / Q000378:metabolism; D014532:Uridine Diphosphate Glucose / Q000378:metabolism
D015226:Dinucleoside Phosphates; D029701:Saccharomyces cerevisiae Proteins; D014500:Uracil Nucleotides; C035436:uridine 5'-tetraphosphate; D014531:Uridine Diphosphate Galactose; D005957:UTP-Glucose-1-Phosphate Uridylyltransferase; D014532:Uridine Diphosphate Glucose