Vesicle SPDP activated

The following protocol is a suggested method for coupling sulfhydryl-containing proteins to SPDP-activated vesicles. 

SPDP also is a popular choice for coupling sulfhydryl-containing molecules to liposomes. PE residues in vesicles may be activated with this crosslinker to form pyridyl disulfide derivatives that can react with sulfhydryls to form disulfide linkages. Unlike the iodoacetyl- and maleimide-based crosslinkers discussed previously, the linkage formed with SPDP is reversible by simple disulfide reduction. Pure PE may be activated with SPDP prior to its incorporation into a liposome,... 

SMPB can be used to activate PE residues to contain sulfhydryl-reactive maleimide groups (Section 2). Lipid vesicles formed with MPB-PE components thus can couple proteins through available —SH groups, forming thioether linkages (Derksen and Scherphof, 1985) (Fig. 356). A comparison with SPDP-produced conjugates con-... 

---