Open AccessHuman Erythrocyte Membrane Acetylcholinesterase. Incorporation into the Lipid Bilayer Structure of Liposomes
Author(s) -
HALL E. Rachel,
BRODBECK Urs
Publication year - 1978
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1978.tb20908.x
Subject(s) - liposome , size exclusion chromatography , phospholipid , chemistry , chromatography , bilayer , lipid bilayer , filtration (mathematics) , dialysis tubing , membrane , dialysis , vesicle , biochemistry , enzyme , medicine , statistics , mathematics
Human erythrocyte acetylcholinesterase was incorporated into liposomes of different phospholipid composition by detergent depletion methods. Complete incorporation of activity into liposomes was achieved. Either by gel filtration or by dialysis 99.96% of the sodium deoxycholate originally present was removed. The preferred method of liposome formation involved the use of dialysis followed by gel filtration, as gel filtration alone resulted in liposomes heterogeneous in size. The liposomes had a diameter of about 30 nm (determined by electron microscopy and gel filtration). Studies involving the use of Triton X‐100 and proteolytic enzymes revealed that at least 70% of the incorporated activity was located on the outer‐side of the liposomes; this percentage was even higher in small liposomes.