[Effect of sodium dodecyl sulfate on biological membranes]

Effect of sodium dodecyl sulfate (SDS) on yeast cells resulting in the cellular proteins release from the cells was examined. The influence of pH, ionic strength, the agent concentration and the cells lipids content on the proteins extraction degree was studied. It is assumed that the proteins release is due to the plasma membrane solubilization under the surfactant treatment. It is established that the mechanism of the monimer--membrane interaction and that of the micelle--membrane interaction are likely to be different. It is shown that micelle-like surfactant--protein complexes can solubilize the membrane as well as the SDS micellies. It is found an increase of the ionic strength decreases the efficiency of the SDS action probably due to an increase of the micelle volume. It is assumed that the efficiency of the SDS action on the cell is limited particularly by the ratio of cell wall pere size to the size of micelles formed by the agent in the solution. It is shown also that removal of the largest portion of the lipids from the yeast cell favours an increase in the efficiency of the SDS extractive action at the agent concentrations larger than the critical micelle concentration value probably due to the corresponding decrease of the amount of the cellular components which must be solubilized by the surfactant micelles.