Glycoprotein-protein associated effects on the permeability of a model membrane

1. The osmotic effects on phospholipid vesicles in the presence and absence of bound glycoprotein and protein were used to determine the permeability to some ions and neutral molecules. 2. The permeation times were registered as a function of membrane surface charge and glycoprotein protein molar ratio in the vesicles. 3. The permeation times for ions varied considerably with the change of glycoprotein protein molar ratio. 4. When neutral molecules passed through the membrane, the permeation times did not change varying glycoprotein-protein molar ratio. 5. In all cases the permeation times did not depend on the surface charge. 6. Our results suggest that topographical distribution of hydrophobic and hydrophilic regions of glycoprotein molecule would play a substantial role and influence the permeability in this case.