FLEXOELECTRIC EFFECTS IN MODEL AND NATIVE MEMBRANES CONTAINING ION CHANNELS

An experimental study of flexoelectricity in model membranes containin g ion pores and native membranes containing ion channels has been unde rtaken with the objective of determining the relationship, if any, bet ween flexoelectricity and ion transport. Model membrane patches contai ning ion pores induced by a blue-green algal toxin, microcystin-LR, an d locust muscle membrane patches containing potassium channels were st udied using patch-clamp techniques. A correspondence was established b etween the presence of open channels and pores and the amplitude of th e 1st harmonic of the total membrane current when the membranes or pat ches were subjected to pressure oscillations. The 2nd harmonic of the membrane current provided a measure of the amplitude of a membrane cur vature induced by pressure, thus making it possible to determine the m embrane flexoelectric coefficient. This study shows that flexoelectric ity could be an effective driving force for ion transport through memb rane pores and channels, thus further highlighting the possible biolog ical significance of this mechano-electric phenomenon.