Effect of primycin on monovalent cation transport of erythrocyte membrane and lipid bilayer.

Abstract
The effects of primycin on the alkali-cation transport of human erythrocytes and on the electric conduction of bimolecular lipid membranes were investigated. In the concentration range of 3 .cntdot. 10-6 to 10-5 primycin increased the permeability of erythrocytes to alkali-cations according to the sequence Cs+ > Rb+ .apprx. K+ .mchgt. Na+, while the conductance of the negatively charged phosphatidylserine bimolecular lipid membrane increased by 2-3 orders of magnitude. The resistance-lowering effect of primycin strongly depended on the cationic species applied and a selectivity order Na+ > K+ > Rb+ > Cs+ was found. A possible mechanism of the primycin-membrane interaction is suggested on the basis of experimental data.