Stoichiometry of lipid-protein interaction and integral membrane protein structure

The stoichiometries of lipid-protein interaction obtained from spin label electron spin resonance experiments with integral membrane proteins are compared with simple geometric models for the intramembranous perimeter that are based on the predicted numbers of transmembrane helices. Deviations from the predicted values provide evidence for oligomerization of the protein in the membrane and/or more complex arrangements of the transmembrane segments. Received: 16 January 1997 / Accepted: 5 March 1997