title: A divalent metal-dependent self-cleaving DNAzyme with a tyrosine side chain.
abstract: The enzymatic incorporation of a phenol-modified 2'-deoxyuridine triphosphate gave rise to a modified DNA library that was subsequently used in an in vitro selection for ribophosphodiester-cleaving DNAzymes in the presence of divalent zinc and magnesium cations. After 11 rounds of selection, cloning and sequencing resulted in 14 distinct sequences, the most active of which was Dz11-17PheO. Dz11-17PheO self-cleaved an embedded ribocytidine with an observed rate constant of 0.20 ± 0.02 min(-1) in the presence of 10 mM Mg(2+) and 1 mM Zn(2+) at room temperature. The activity was inhibited at low concentrations of Hg(2+) cations and somewhat higher concentrations of Eu(3+) cations.
authors.affiliation: Chemistry Department, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada.
authors.forename: Curtis H
authors.initials: CH
authors.lastname: Lam
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Hipolito
authors.forename: Marcel
authors.initials: M
authors.lastname: Hollenstein
authors.forename: David M
authors.initials: DM
authors.lastname: Perrin
mesh_terms: D001483:Base Sequence; D002413:Cations, Divalent / Q000737:chemistry; D021881:DNA, Catalytic / Q000737:chemistry* / Q000378:metabolism; D007700:Kinetics; D008274:Magnesium / Q000737:chemistry*; D008628:Mercury / Q000737:chemistry*; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D014443:Tyrosine / Q000737:chemistry / Q000378:metabolism; D015032:Zinc / Q000737:chemistry*
chemical_list: D002413:Cations, Divalent; D021881:DNA, Catalytic; D014443:Tyrosine; D008628:Mercury; D008274:Magnesium; D015032:Zinc