Ternary Zinc(II)-Dipeptide Complexes for the Hydrolytic Cleavage of DNA at Physiological pH

Abstract

A series of Zn(II) complexes with cysteinylglycine (CysGly) and histidylserine (HisSer), and of CysGly and histidylphenylalanine (HisPhe) were investigated. Complex stabilities were determined potentiometrically, and binding geometries were probed by means of 1H-NMR spectroscopy, using Co(II) instead of Zn(II) as a spectroscopic marker. The ternary 1:1:1 complexes [Zn(II)(CysGly)(HisSer)] and [Zn(II)(CysGly)(HisPhe)] were shown by UV experiments, fluorescence titration, and gel electrophoresis to intercalate with DNA, and to hydrolytically cleave supercoiled DNA (form-I), partly also circular (form-II) DNA, under physiological conditions (37 degrees, H2O, pH 7.5).

Zinc(ii) complexes as hydrolytic catalysts of phosphate diester cleavage: from model substrates to nucleic acids

“…More recently, the Zn 2+ complexes of dipeptides, 17 tripeptides 18 and cyclotriphospazenes 19 have been shown to be active in the cleavage of plasmid DNA with rate constants in the 10 À5 -10 À6 s À1 range. However, these results have been obtained using high concentrations of metal complex (1-2 mM), making rather complicated comparisons with other systems.…”

Bioinspired Deposition of TiO2 Thin Films Induced by Hydrophobins

“…According to the existing reports, , during the self-assembly, the protein molecules are expected to undergo a conformational change by exposing their polar groups on the hydrophilic piranha-treated silica surface and apolar groups at the other surface. From the literature it is also evident that the amino acids as free molecules or incorporated in a protein that are more likely to form complexes with metal ions are His, Cys, and Glu. − Similarly, there is a possibility for chemical interaction of amino acids in hydrophobins with the Ti(IV)−hydroxo complex through their functional groups such as COO − , CO, OH, and NH 2 .…”

Dipeptide interactions with Zn(II)–cyclen artificial model for molecular recognition

“…Zinc(II) ion is a crucial biometal ion frequently occurring in proteins and playing essential role in initial stage of the peptide amide bond cleavage. Thus, a lot of model metal complexes have been designed with aim to solve the selective peptide cleavage mechanism in natural surroundings, and a large number of papers have already been published in this field (Gelinsky et al, 2002;Reddy and Mohan, 2002;Mylonas et al, 2004;Rivas et al, 2004;Reddy et al, 2005;Karambelkar et al, 2006;Vahrenkamp, 2007;Jakab et al, 2008;Trzaskowski et al, 2008;Faller and Hureau, 2009;Valensin et al, 2009). Glycine oligopeptides themselves are coordinated to Zn(II) mainly through carboxylate with a stability constant; log K = 0.7 at pH < 4.…”