Interaction of cationic phospholipid vesicles with carbonic anhydrase.
The possibility of entrapping the enzyme carbonic anhydrase into liposomes, in order to obtain small, membrane-confined bioreactors for biotechnological or biomedical applications, was studied. Neutral liposomes (dipalmitoylphosphatidylcholine/cholesterol) or cationic liposomes (dipalmitoylphosphatidylcholine/cholesterol/stearylamine) with different dipalmitoylphosphatidylcholine/stearylamine ratios have been used to trap carbonic anhydrase. Kinetic experiments showed that carbonic anhydrase was being trapped into cationic liposomes, but not into neutral ones. A significant amount of carbonic anhydrase was sitting onto the external surface of liposomes when the ratio dipalmitoylphosphatidylcholine/cholesterol/stearylamine was 6:3:1, but not when it was 5:3:2. Morphological analysis by electron microscopy showed that the presence of carbonic anhydrase induced a significant swelling in the 6:3:1 cationic vesicles, related to the activity of the enzyme.
Dipartimento di Ingegneria Chimica, Facoltà di Ingegneria, Università degli Studi di Roma La Sapienza, Italy.
M C
MC
Annesini
L
L
Di Marzio
A
A
Finazzi-Agrò
A L
AL
Serafino
G
G
Mossa
D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry; D000588:Amines / Q000737:chemistry; D001709:Biotechnology; D002256:Carbonic Anhydrases / Q000378:metabolism*; D002784:Cholesterol / Q000737:chemistry; D007700:Kinetics; D008081:Liposomes / Q000737:chemistry / Q000378:metabolism*; D008854:Microscopy, Electron
D000588:Amines; D008081:Liposomes; D015060:1,2-Dipalmitoylphosphatidylcholine; D002784:Cholesterol; D002256:Carbonic Anhydrases; C009317:stearylamine