Electron spin resonance studies on interaction of complement proteins with erythrocyte membranes.

AUTOR(ES)

Dahl, C E

RESUMO

Sheep erythrocytes have been spin labeled with 5-, 12-, and 16-nitroxystearic acid in order to investigate complement-induced changes in the physical state of the lipid bilayer. Formation of osmotic lesions in the membrane causes an increase in the fluidity of the membrane which overcomes the decrease in membrane fluidity caused by the interaction of the complement proteins. A decrease in membrane fluidity is observed only when complement-lysed membranes are resealed or when complement proteins react with isosmolar ghosts that do not undergo osmotic lysis. The decrease in bulk fluidity of the membrane is first observed when C8 binds to the membranes bearing C5b67 and is enhanced upon the subsequent binding of C9. The decrease in membrane fluidity shown by the electron spin resonance spectra of spin-labeled fatty acids suggests that certain of the complement proteins penetrate the membrane and interact with hydrophobic regions of the lipid bilayer.

Documentos Relacionados

• Spin-label electron spin resonance studies on the interactions of lysine peptides with phospholipid membranes.
• Electron spin resonance studies of acyl chain motion in reconstituted nicotinic acetylcholine receptor membranes.
• Lipopolysaccharide interaction with rabbit erythrocyte membranes.
• Interaction of sickle cell hemoglobin with erythrocyte membranes.
• A spin label study of the effect of chrysotile asbestos on erythrocyte membranes.