title: The hydrolysis of 5'-CAP dinucleotide analogs: catalysis by bi- and terpyridine complexes of Cu²⁺ and Zn²⁺ ions.
abstract: The kinetics of the hydrolysis of P(1)-(7-methylguanosinyl-5') P(3)-(guanosinyl-5') triphosphate (m(7)GpppG), P(1)-(7-methylguanosinyl-5') P(4)-(guanosinyl-5') tetraphosphate (m(7)GppppG), and diadenosine 5', 5'( ')-P(1),P(3) -triphosphate (ApppA) in the presence of several Cu(2+) or Zn(2+) ions complexed with bi- or terpyridine has been studied at pH 8.0 and 60 °C. Time-dependent product distributions at various metal complex concentrations have been determined by capillary zone electrophoresis and reversed-phase high performance liquid chromatography. The results show that the predominant hydrolytic reaction is the cleavage of 5',5'-oligophosphate bridge, with Cu(2+) complexes being approximately 15-fold more efficient catalysts than Zn(2+) chelates. In addition, the effect of metal ions complexes at pH 7.0 and 8.0 on the imidazole ring opening in m(7)Gua mononucleotides has been studied. The influence of Cu(2+) complexes on imidazole ring cleavage of mononucleotides is modest, whereas Zn(2+) complexes are almost inactive.
authors.affiliation: Department of Physics and Biophysics, University of Warmia and Mazury in Olsztyn, Olsztyn, Poland. alicja.stachelska@uwm.edu.pl
authors.forename: Alicja
authors.initials: A
authors.lastname: Stachelska-Wierzchowska
authors.forename: Zbigniew J
authors.initials: ZJ
authors.lastname: Wieczorek
authors.forename: Jacek
authors.initials: J
authors.lastname: Wierzchowski
mesh_terms: D002384:Catalysis; D056148:Chromatography, Reverse-Phase; D056831:Coordination Complexes / Q000138:chemical synthesis* / Q000737:chemistry; D003300:Copper / Q000737:chemistry*; D019075:Electrophoresis, Capillary; D006150:Guanine Nucleotides / Q000138:chemical synthesis* / Q000737:chemistry; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007093:Imidazoles / Q000737:chemistry; D007477:Ions / Q000737:chemistry; D007700:Kinetics; D018716:Molecular Mimicry; D015394:Molecular Structure; D011725:Pyridines / Q000138:chemical synthesis* / Q000737:chemistry; D012260:Ribonucleases / Q000737:chemistry; D015032:Zinc / Q000737:chemistry*
chemical_list: D056831:Coordination Complexes; D006150:Guanine Nucleotides; D007093:Imidazoles; D007477:Ions; D011725:Pyridines; D003300:Copper; D012260:Ribonucleases; D015032:Zinc