Modulation of properties of phospholipid membranes by the long-chain polyprenol (C-160)

The electrical measurements of phospholipid bilayers and the studies of pho spholipid vesicles by using the transmission electron microscopy (TEM) show ed that dotriacontaprenol (C-160) isolated from leaves of Spermatophyta inf luences some properties of membranes. The current-voltage characteristics, the membrane conductance-temperature relationships, the membrane breakdown voltage and the membrane capacitance have been measured for different mixtu res of C-160/DOPC. The membrane conductance, the activation energy of ion m igration across the membrane and the membrane thickness were determined. Do triacontaprenol decreases the membrane breakdown voltage, the activation en ergy and the membrane capacitance, and increases the membrane conductance a nd the membrane hydrophobic thickness. The analysis of TEM micrographs show s several characteristic structures, which have been described. The results indicate that dotriacontaprenol increases the membrane elasticity and modu lates the surface curvature of the membranes by the formation of fluid micr odomains. We suggest that the long polyprenols facilitate the formation of transmembrane, ions-conductive pores. (C) 2000 Elsevier Science Ireland Ltd . All rights reserved.