Interactions of diastereomeric tripeptides of lysyl-5-fluorotryptophyllysine with DNA. 2. Optical, fluorine-19 NMR and strand cleavage studies of apurinic DNA complexes
- 30 July 1985
- journal article
- research article
- Published by American Chemical Society (ACS) in Biochemistry
- Vol. 24 (16) , 4341-4345
- https://doi.org/10.1021/bi00337a013
Abstract
The interactions of the diastereomers lysyl-5-fluoro-L-tryptophyllysine and lysyl-5-fluoro-D-tryptophyllysine with apurinic DNA were examined as a model for the action of DNA repair enzymes. The binding characteristics of the tripeptide diastereomers to DNA, modified to contain .apprx. 5% apurinic sites, were studied by measuring 19F NMR parameters, fluorescence quenching, and activity in promoting single-strand cleavage of plasmid DNA. The affinities of each of the peptides to apurinic DNA are similar to those for native DNA. The 19F NMR chemical shift and relaxation behavior indicates that both diastereomers form complexes with apurinic DNA that are distinct from those formed with native DNA. The 19F NMR measurements differ for the L-Trp and D-Trp complexes with apurinic DNA. In spite of these diffeences, when either of the tripeptide diastereomers is incubated with plasmid DNA containing apurinic sites, no difference in the rate of single-strand cleavage of the DNA is detectable.This publication has 1 reference indexed in Scilit:
- Specific recognition of apurinic sites in DNA by a tryptophan-containing peptide.Proceedings of the National Academy of Sciences, 1981