TY - JOUR
T1 - Cooperative strand invasion of supercoiled plasmid DNA by mixed linear PNA and PNA-peptide chimeras
AU - Lundin, Karin E.
AU - Ge, Rongbin
AU - Svahn, Mathias G.
AU - Törnquist, Elisabeth
AU - Leijon, Mikael
AU - Brandén, Lars J.
AU - Smith, C. I.Edvard
N1 - Funding Information:
This work was supported by grants from the Sigurd and Elsa Golje Memorial Foundation, Syskonen Svenssons Medical Research Foundation, the Swedish Science Foundation, the Wallenberg Foundation, and by the European Union project EURO GENE DRUG (QLK 3-CT-2002-01997).
PY - 2004/4
Y1 - 2004/4
N2 - Peptide nucleic acid (PNA) is a DNA analog with broad biotechnical applications, and possibly also treatment applications. Its suggested uses include that of a specific anchor sequence for biologically active peptides to plasmids in a sequence-specific manner. Such complexes, referred to as Bioplex, have already been used to enhance non-viral gene transfer in vitro. To investigate how hybridization of PNAs to supercoiled plasmids would be affected by the binding of multiple PNA-peptides to the same strand of DNA, we have developed a method of quantifying the specific binding of PNA using a PNA labeled with a derivative of the fluorophore thiazole orange (TO). Cooperative effects were found at a distance of up to three bases. With a peptide present at the end of one of the PNAs, steric hindrance occurred, reducing the increase in binding rate when the distance between the two sites was less than two bases. In addition, we found increased binding kinetics when two PNAs binding to overlapping sites on opposite DNA strands were used, without the use of chemically modified bases in the PNAs.
AB - Peptide nucleic acid (PNA) is a DNA analog with broad biotechnical applications, and possibly also treatment applications. Its suggested uses include that of a specific anchor sequence for biologically active peptides to plasmids in a sequence-specific manner. Such complexes, referred to as Bioplex, have already been used to enhance non-viral gene transfer in vitro. To investigate how hybridization of PNAs to supercoiled plasmids would be affected by the binding of multiple PNA-peptides to the same strand of DNA, we have developed a method of quantifying the specific binding of PNA using a PNA labeled with a derivative of the fluorophore thiazole orange (TO). Cooperative effects were found at a distance of up to three bases. With a peptide present at the end of one of the PNAs, steric hindrance occurred, reducing the increase in binding rate when the distance between the two sites was less than two bases. In addition, we found increased binding kinetics when two PNAs binding to overlapping sites on opposite DNA strands were used, without the use of chemically modified bases in the PNAs.
KW - Asymmetric cyanine dye
KW - Mixed-base PNA
KW - Peptide nucleic acids (PNA)
KW - Supercoiled DNA
UR - http://www.scopus.com/inward/record.url?scp=2042542807&partnerID=8YFLogxK
U2 - 10.1016/j.bioeng.2003.10.003
DO - 10.1016/j.bioeng.2003.10.003
M3 - Article
C2 - 15113558
AN - SCOPUS:2042542807
SN - 1389-0344
VL - 21
SP - 51
EP - 59
JO - Biomolecular Engineering
JF - Biomolecular Engineering
IS - 2
ER -