[DNA-phospholipid interactions. A study using lipid-specific fluorescent and photoreactive probes].

The interaction of phospholipids with phage T7 DNA was investigated using anthryl-vinyl-labeled and photoactivable phosphatidylcholine and sphingomyelin. Fluorescence polarization studies demonstrated that, in the presence of DNA, the fluorophore mobility is diminished as its distance from the polar head-group is increased. Immobilization of lipid chains is enhanced by Ca2+ ions, the effect being more pronounced for sphingomyelin than for phosphatidylcholine derivatives.

[DNA-phospholipid interaction. 31P-NMR study].

The phage T7 DNA complexes with various phospholipids (PL) were studied by 31P NMR at PL/nucleotide molar ratio of 2 : 1. Using a phosphatidylcholine thion analogue, the contributions of PL and DNA into the 31P NMR spectrum of the complex were estimated. It was found that PL-DNA interaction results in partial immobilizing ability of PL depends on their structure, increasing in the following row: phosphatidylcholine-phosphatidylethanolamine less than sphingomyelin less than or equal to ternary mixture of these PL.