title: Active species for Ce(IV)-induced hydrolysis of phosphodiester linkage in cAMP and DNA.
abstract: The hydrolysis of cyclic adenosine 3',5'-monophosphate and 2'-deoxythymidylyl(3'-5')2'-deoxythymidine by Ce(NH4)2(NO3)6 was kinetically studied. The rate of hydrolysis was fairly proportional to the concentration of [Ce2(IV) (OH)4]4+ , showing that this is the catalytically active species. According to quantum-chemical calculation, the two Ce(IV) ions in this [Ce2(IV) (OH)4]4+ cluster are bridged by two OH residues. Upon the complex formation with H2 PO4- (a model compound for the phosphodiesters), these two Ce(IV) ions bind the two oxygen atoms of the substrate and enhance the electrophilicity of the phosphorus atom. The catalytic mechanism of Ce(IV)-induced hydrolysis of phosphodiesters has been proposed on the basis these results.
authors.affiliation: Research Center for Advanced Science and Technology, The University of Tokyo, Komaba, Tokyo, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Sumaoka
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Furuki
authors.forename: Yuki
authors.initials: Y
authors.lastname: Kojima
authors.forename: Masahiko
authors.initials: M
authors.lastname: Shibata
authors.forename: Kimihiko
authors.initials: K
authors.lastname: Hirao
authors.forename: Naoya
authors.initials: N
authors.lastname: Takeda
authors.forename: Makoto
authors.initials: M
authors.lastname: Komiyama
mesh_terms: D002563:Cerium / Q000737:chemistry*; D000242:Cyclic AMP / Q000737:chemistry*; D004247:DNA / Q000737:chemistry*; D004952:Esters / Q000737:chemistry*; D006868:Hydrolysis; D007700:Kinetics; D015394:Molecular Structure; D011465:Prostaglandins, Synthetic / Q000737:chemistry
chemical_list: D004952:Esters; D011465:Prostaglandins, Synthetic; D002563:Cerium; C026677:9 alpha,11 alpha,15 alpha-trihydroxy-16-phenoxy-17,18,19,20-tetranorprosta-4,5,13-trienoic acid; D004247:DNA; D000242:Cyclic AMP