[DNA-bound lipids from eukaryotic (loach spermatozoa, pigeon erythrocytes) and prokaryotic (E. coli B, phage T2) cells].

Using thin-layer chromatography, some specific DNA-bound neutral lipids and phospholipids of loach spermatozoa, pigeon erythrocytes, E. coli B and phage T2 cells were studied. These lipids are represented by loosely and firmly bound components. The content of neutral lipids in the above DNAs (per mg of DNA) is 10.6, 4.8, 7.81 and 1.43 micrograms, respectively; that of phospholipids is 4.31, 1.28, 1.14 and 0.54 micrograms, respectively. The eucaryotic DNA-bound lipids are highly deficient of free cholesterol, phosphatidylcholine, phosphatidylinositol and phosphatidylserine but are rich in cardiolipin, phosphatidylethanolamine, cholesterol esters, diglycerides and free fatty acids. The quantitative and qualitative composition of DNA-bound lipids of loach spermatozoa changes during the transition from the superhelical to the relaxed conformation of DNA. Procaryotic DNA-bound neutral lipids are also represented by the free cholesterol, diglyceride and free fatty acid fractions, whereas the DNA-bound phospholipids of procaryotes consist of only two fractions, i.e., cardiolipin and phosphatidylethanolamine. The role of DNA-bound lipids in the structural and functional organization of eucaryotic and procaryotic genomes is discussed.