title: Synthesis of gamma-monodentate and beta, gamma-bidentate CrITP. Isolation and characterization of the two chelation isomers and the individual diastereomers of beta, gamma-bidentate CrITP.
abstract: The two chelation isomers of CrITP, gamma-monodentate and beta, gamma-bidentate CrITP, as well as the diastereomers of beta, gamma-bidentate CrITP were synthesized, isolated, and characterized. Synthesis of these complexes was done using pH titration methods similar to that described by Cleland [W.W. Cleland, Methods Enzymol. 87, 159 (1982)], and separation of the two chelation isomers was accomplished with DEAE-sephadex A-25 using 0-0.3 N linear HCl gradient. Diastereomer separation (analytical and preparative scales) of beta, gamma-bidentate CrITP using reverse-phase high-performance liquid chromatography, and then analysis of the diastereomers with circular dichroism spectroscopy, shows four diastereomers that exist as two pairs of mirror-image isomers, similar to the four diastereomers of beta, gamma-bidentate CrATP as presented by Dunaway-Mariano and Cleland [D. Dunaway-Mariano and W.W. Cleland, Biochemistry 19, 1496 (1980)]. Reverse-phase high-performance liquid chromatography analysis of gamma-monodentate CrITP shows the presence of two major peaks, both of which convert to beta, gamma-bidentate CrITP upon incubation at pH 6.0 for 1 hr.
mesh_terms: D002614:Chelating Agents; D002851:Chromatography, High Pressure Liquid; D002857:Chromium; D002942:Circular Dichroism; D007291:Inosine Monophosphate; D007292:Inosine Nucleotides; D007293:Inosine Triphosphate; D008968:Molecular Conformation; D010710:Phosphates; D013237:Stereoisomerism
chemical_list: D002614:Chelating Agents; D007292:Inosine Nucleotides; D010710:Phosphates; D002857:Chromium; D007291:Inosine Monophosphate; D007293:Inosine Triphosphate