DNA-fiber EPR investigation of the influence of amino-terminal residue stereochemistry on the DNA binding orientation of Cu(II).Gly-Gly-His-derived metallopeptides.

ABSTRACT: DNA fiber EPR was used to investigate the DNA binding stabilities and orientations of Cu(II).Gly-Gly-His-derived metallopeptides containing D- vs. L-amino acid substitutions in the first peptide position. This examination included studies of Cu(II).D-Arg-Gly-His and Cu(II).D-Lys-Gly-His for comparison to metallopeptides containing L-Arg/Lys substitutions, and also the diastereoisomeric pairs Cu(II).D/L-Pro-Gly-His and Cu(II).D/L-Pro-Lys-His. Results indicated that L-Arg/Lys to D-Arg/Lys substitutions considerably randomized the orientation of the metallopeptides on DNA, whereas the replacement of L-Pro by D-Pro in Cu(II).L-Pro-Gly-His caused a decrease in randomness. The difference in the extent of randomness observed between the D- vs. L-Pro-Gly-His complexes was diminished through the su

SUBMITTER: Hamada H 

PROVIDER: S-EPMC2140950 | biostudies-literature | 2007 Oct

REPOSITORIES: biostudies-literature