Advances in Cyanine - Amino Acid Conjugates and Peptides for Sensing of DNA, RNA and Protein Structures

Small molecule spectrophotometric probes for DNA/RNA and proteins are of the utmost importance for diagnostics in biochemical and biomedical research. Both, naturally occurring and synthetic probes, often include peptide sequence responsible for the selectivity toward the particular target; however, commercially available dyes are restricted to single point attachment to the peptide (having one reactive group). Here presented are our recent advances in the development of novel amino acidfluorophore probes, with the unique characteristic of free N- and C-terminus available for incorporation at any peptide backbone position. Intriguingly, already monomeric amino acid-fluorophores showed recognition among various DNA/RNA, whereby steric impact and contribution of halogens is systematically studied. Moreover, some dyes revealed intracellular mitochondria specificity. Further, several hetero-dimeric chromophore systems were prepared, demonstrating that synergistic effect can lead to simultaneous DNA, RNA and protein fluorimetric recognition, combined with enzyme inhibition. Also, homodimeric cyanines equipped with chlorine revealed intriguing DNA/RNA selectivity in respect to well-known parent TOTO and YOYO dyes.