title: GTP, a nonsubstrate of ATP citrate lyase, is a phosphodonor for the enzyme histidine autophosphorylation.
abstract: ATP citrate lyase (EC 4.3.1.8.) was shown to be a major phosphorylation protein of a fraction derived from Zajdela rat hepatoma by chromatography on heparin-Ultrogel, after the incubation with [gamma-32P]ATP or [gamma-32P]GTP. Histidine was the only amino acid in the purified enzyme phosphorylated by [gamma-32P]ATP or [gamma-32P]GTP in the autocatalytic reaction which occurred apparently through an intramolecular mechanism regardless of a donor of phosphate. GTP inhibits the ATP-dependent autophosphorylation competitively despite its failure to replace ATP in the formation of acetyl-CoA catalyzed by this enzyme.
authors.affiliation: Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Praha.
authors.forename: Z
authors.initials: Z
authors.lastname: Tuhácková
authors.forename: J
authors.initials: J
authors.lastname: Krivánek
mesh_terms: D001275:ATP Citrate (pro-S)-Lyase / Q000302:isolation & purification / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D002846:Chromatography, Affinity; D002852:Chromatography, Ion Exchange; D004591:Electrophoresis, Polyacrylamide Gel; D006160:Guanosine Triphosphate / Q000378:metabolism* / Q000494:pharmacology; D006165:Guanylyl Imidodiphosphate / Q000494:pharmacology; D006639:Histidine; D007700:Kinetics; D008114:Liver Neoplasms, Experimental / Q000201:enzymology*; D008970:Molecular Weight; D010750:Phosphoproteins / Q000302:isolation & purification / Q000378:metabolism*; D010761:Phosphorus Radioisotopes; D010766:Phosphorylation; D051381:Rats; D017208:Rats, Wistar; D013379:Substrate Specificity
chemical_list: D010750:Phosphoproteins; D010761:Phosphorus Radioisotopes; D006165:Guanylyl Imidodiphosphate; D006639:Histidine; D006160:Guanosine Triphosphate; D000255:Adenosine Triphosphate; D001275:ATP Citrate (pro-S)-Lyase