Phosphoglycerate kinase from yeast synthesizes guanosine 5'-tetraphosphate.
Yeast phosphoglycerate kinase (PGK; EC 2.7.2.3) synthesizes adenosine 5'-tetraphosphate (ppppA) from ATP and 1,3-bisphosphoglycerate. Using an HPLC assay, we have shown the synthesis of guanosine 5'-tetraphosphate (ppppG; 0.17 nmol.min-1.PGK unit-1) characterized by its u.v. spectrum, HPLC behavior, and enzymatic digestions. That the synthesis of ppppG is catalyzed by PGK itself and not by a contaminant was shown because it depended on 3-phosphoglycerate (as a source of 1,3-bisphosphoglycerate), coeluted with PGK activity upon gel filtration, and the thermal inactivation of the PGK and the ppppG synthetic activity were parallel.
García-Díaz
M
M
Departamento de Bioquímica, Facultad de Medicina, Universidad de Extremadura, Badajoz, Spain.
Canales
J
J
Sillero
M A
MA
Sillero
A
A
Cameselle
J C
JC
D000255:Adenosine Triphosphate / Q000378:metabolism; D000469:Alkaline Phosphatase / Q000378:metabolism; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D004163:Diphosphoglyceric Acids / Q000378:metabolism; D006150:Guanine Nucleotides / Q000096:biosynthesis*; D006159:Guanosine Tetraphosphate / Q000096:biosynthesis*; D007700:Kinetics; D010735:Phosphoglycerate Kinase / Q000378:metabolism*; D013696:Temperature; D015003:Yeasts / Q000201:enzymology*
D004163:Diphosphoglyceric Acids; D006150:Guanine Nucleotides; D006159:Guanosine Tetraphosphate; D000255:Adenosine Triphosphate; D010735:Phosphoglycerate Kinase; D000469:Alkaline Phosphatase