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The rate of 32Pi incorporation into the main membrane phospholipid fractions, i.e. phosphatidylcholine (PC), phosphatidylethanolamine (PE) and phosphatidylinositol (PI), as well as their contents in the cells during synchronous growth of the myxomycete, Physarum polycephalum, have been studied. It has been found that both the phospholipid levels and the rates of 32Pi incorporation increase during the S phase till the early G2 phase, remain nearly constant during the G2 phase and fall to the initial level at the end of the G2 phase and in mitosis. It has been revealed that the rate of 32Pi incorporation into PC is very low compared to PE and PI, in spite of the fact that the PC level is the highest. The possible reasons of this phenomenon are discussed.

The extent of homology of the nuclear matrix DNA isolated from the macroplasmodium of Physarum polycephalum at G2- and S-phases of the cell cycle was studied using the molecular reassociation method. The results obtained point to the incomplete homology of DNA samples prepared at G2- phases as compared to those obtained at S-phase. Bearing this in mind it seems reasonable to suppose that the DNA template may transfer through the nuclear matrix-attached replicative complex under the replication.

Electrical properties of BLM formed from lipid components of rat liver mitochondria were studied. The lipids were obtained after preliminary 40 second incubation of mitochondria in the medium containing succinic acid. BLM electroconductivity in the medium with calcium chloride (8--20 mM) is 10--100 times higher than the initial electroconductivity in tris-HC1 at pH 7.5, and in the presence of potassium chloride and magnesium chloride it differes little from the initial value. The transmembrane potential difference per 10-fold concentration gradient of Ca2+, Mg2+, and K+ is approximately 27 mV, approximately 15 mV and approximately 22 mV correspondingly. By means of biionic potential method the following selectivety line for cations is formed: Ca2+ greater than Sr2 greater than or equal to Mg2+ greater than K+. La3+ ions inhibit the transport of Ca2+ through the BLM studied.