Synthesis, photophysical effects, and DNA targeting properties of oxazole yellow-peptide bioconjugates.
The design of a dsDNA-sensitive fluorescent bioconjugate capable of targeting a specific DNA sequence with high efficiency is described. The bioconjugate has the molecular recognition features of the polypeptide from a DNA-binding protein and the dsDNA-dependent fluorescence of an intercalating dye. The DNA sequence selectivity of the probe was characterized, as were the changes in photophysical properties of the dye upon covalent linkage to the peptide to assess whether such bioconjugates could function as molecular probes of gene sequences. The oxazole yellow-peptide bioconjugate exhibits DNA recognition and binding affinity comparable to the native Hin recombinase protein. Examination of photophysical effects to dye conjugation indicates a negligible affect on the fluorescence quantum yield. Fluorescence studies indicate this molecular probe is useful to determine the presence of a given DNA target sequence and gives negligible fluorescence in the absence of a given target site. Using the synthetic route described here, bioconjugates could be designed using different combinations of DNA recognition polypeptides and cyanine dyes to generate an array of sequence specific and wavelength specific probes.
Department of Chemistry, Michigan Technological University, 1400 Townsend Drive, Houghton, Michigan 49931, USA. mthomps@mtu.edu
Martin
M
Thompson
D001583:Benzoxazoles / Q000737:chemistry*; D004247:DNA / Q000737:chemistry*; D004254:DNA Nucleotidyltransferases / Q000235:genetics / Q000378:metabolism; D005456:Fluorescent Dyes / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism; D015394:Molecular Structure; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D010777:Photochemistry; D011804:Quinolines / Q000737:chemistry*; D011993:Recombinant Fusion Proteins / Q000138:chemical synthesis / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
D001583:Benzoxazoles; D005456:Fluorescent Dyes; D010455:Peptides; D011804:Quinolines; D011993:Recombinant Fusion Proteins; C097015:oxazole yellow; D004247:DNA; D004254:DNA Nucleotidyltransferases; C059997:Hin recombinase