“…Upon addition of basic oligopeptides or polypeptides, the melting temperatures of RNA and DNA are elevated, indicating an increased stability of the double helix (Tsuboi et al, 1966;Olins et al, 1968;Gabbay et al, 1973;Mandel & Fasman, 1974). Lysinecontaining peptides with (Ala-Lys)", (Gly-Lys)", (Lys-Ala-Ala)", and (Lys-Leu-Ala)" sequences act in a manner similar to that of polyamines in inducing Z-DNA (Takeuchi et al, 1991(Takeuchi et al, , 1994Votavova et al, 1991;Votavova & Sponar, 1993). Our data extend the list of DNA structures known to be stabilized by basic oligopeptides to include intermolecular triplex DNA.…”