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PubMed · 10471821

Chiral DNA packaging in DNA-cationic liposome assemblies.

N J Zuidam·Y Barenholz·A Minsky
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Abstract

Recent studies have indicated that the structural features of DNA-lipid assemblies, dictated by the lipid composition and cationic lipid-to-DNA ratio, critically affect the efficiency of these complexes in acting as vehicles for cellular delivery of genetic material. Using circular dichroism we find that upon binding DNA, positively-charged liposomes induce a secondary conformational transition of the DNA molecules from the native B form to the C motif. Liposomes composed of positively-charged and neutral 'helper' lipids, found to be particularly effective as transfecting agents, induce - in addition to secondary conformational changes - DNA condensation into a left-handed cholesteric-like phase. A structural model is presented according to which two distinct, yet inter-related modes of DNA packaging coexist within such assemblies. The results underline the notion that subtle changes in the components of a supramolecular assembly may substantially modulate the interplay of interactions which dictate its structure and functional properties.

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CationsCircular DichroismDNAFatty Acids, MonounsaturatedLiposomesNucleic Acid ConformationOsmolar ConcentrationPhosphatidylethanolaminesQuaternary Ammonium CompoundsStereoisomerismJournal ArticleResearch Support, Non-U.S. Gov't

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N J Zuidam, Y Barenholz, A Minsky. 1999-09-03. Chiral DNA packaging in DNA-cationic liposome assemblies.. https://doi.org/10.1016/s0014-5793(99)01053-4

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