Hiroyuki Ueyama

Tetrakis-acridinyl peptide: A novel fluorometric reagent for nucleic acid analysis based on the fluorescence dequenching upon DNA binding

Tetrakis-acridinyl peptide 1 assuming a right-handed helical stacked conformation of the acridinyl units can bind to DNA duplex with a very high affinity of 10(8) (M-bp)(-1) even at a high salt concentration of 0.2 M NaCl, irrespective of the base composition. Peptide 1 gave rise to 1600-times enhancement of its fluorescence upon binding to an AT polymer due to the collapse of this stacked structure, but the fluorescence is not enhanced with a GC polymer, though the binding constants of 1 for both polymers were the same.

Fluorescence enhancement of bis-acridine orange peptide, BAO, upon binding to double stranded DNA

Bis-acridine orange peptides carrying two acridine oranges at the epsilon-amino moieties of both terminal lysines of a tetra(lysine) chain showed a ca. 200-fold fluorescence enhancement upon addition of double stranded DNA.

Bis-intercalation-triggered fluorescence: specific detection of double stranded DNA and AT content estimation.

Detection of double stranded DNA and estimation of the AT content in DNA of unknown concentration could be achieved with a bis-acridinyl peptide carrying fluorescein, FKA.