Interactions between Cationic Lipid Bilayers and Model Chromatin

• Published in: Langmuir Vol. 26; no. 15; pp. 12488 - 12492
• Main Authors: Lundberg, Dan, Berezhnoy, Nikolay V, Lu, Chenning, Korolev, Nikolay, Su, Chun-Jen, Alfredsson, Viveka, Miguel, Maria da Graça, Lindman, Björn, Nordenskiöld, Lars
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 03.08.2010
• Subjects: Cations - chemistry; Chemical Sciences; Chemistry; Chromatin - chemistry; Colloidal state and disperse state; DNA - chemistry; Exact sciences and technology; Fysikalisk kemi; General and physical chemistry; Kemi; Lipid Bilayers - chemistry; Membranes; Models, Molecular; Natural Sciences; Naturvetenskap; Physical Chemistry; Reference; Liposome; Lipids; Entropy; Complexes; Bilayer; Charge density; Particle; Lamellar structure; DNA; Counter ion; Models; Dissociation; Thermodynamic properties; Release
• ISSN: 0743-7463; 1520-5827
• DOI: 10.1021/la1014658

Complexes formed in mixtures of cationic liposomes of varying charge density and nucleosome core particles (NCPs) or nucleosome arrays have been characterized. Under most of the conditions studied, the lipids and NCPs or arrays formed lamellar structures similar to those obtained with the liposomes and pure DNA. Thus, the dissociation of DNA from the NCP or nucleosome array and the formation of a DNA−lipid complex is thermodynamically favored, which can likely be ascribed mainly to the gain in entropy on release of the small counterions. Only at very low liposome charge densities are there indications that the NCPs/arrays do not dissociate upon interaction with the lipid bilayers. The reported results can serve as a valuable reference point in investigations of biologically more relevant systems.