Lateral diffusion of M-13 coat protein in model membranes.

A fluorescent derivative of the M-13 phage coat protein (molecular weight 5260) was reconsituted into oriented multilayers and giant liposomes of dimyristoylphosphatidylcholine. The rate of lateral diffusion of the labeled protein in the fluid phase was measured as a function of temperature and found to be comparable to that of lipid probes. The protein was found to have a nonuniform lateral distribution in the solid phase of both types of model membranes. Cardiolipin (0.5 mol %) included in the multibilayers did not have any substantial effect upon the rate of diffusion.