Figure 9. Mutation of cysteine residues singly or in combination and effects on MPEG-5 reactivity.

Microsomal membranes prepared from COS cells transiently transfected with the indicated point mutations were screened for reactivity with MPEG-5 (0.5 mM) for 5 min as described in the Experimental section. The results shown are representative of two or three independent experiments.