Reconstitution of cytochrome c oxidase in phospholipid vesicles containing polyvinylic polymers.
Cytochrome c oxidase was reconstituted in phospholipid vesicles in the presence of highly hydrophobic poly(vinyl alkanoate) polymers. Electron-microscopy observations demonstrated that polymer interaction with the lipid phase induces vesicles to adopt smaller diameters than those typical of standard proteoliposomes. Functional characterization of these polymer-proteoliposome structures indicates that the reconstitution of the enzyme proceeds efficiently without causing either scrambling of the protein orientation in the membrane or loss of respiratory control. A clear dependence of respiratory control ratio on vesicle size was also demonstrated, which is in agreement with a previous model proposed for control of activity of cytochrome c oxidase vesicles [Brunori, Sarti, Colosimo, Antonini, Malatesta, Jones & Wilson (1985) EMBO J. 4, 2365-2368].
Sarti
P
P
Department of Biomedical Sciences, Technology and Biometry, University of L'Aquila, Italy.
Antonini
G
G
Malatesta
F
F
Vallone
B
B
Villaschi
S
S
Brunori
M
M
Hider
R C
RC
Hamed
K
K
D000818:Animals; D003576:Electron Transport Complex IV / Q000378:metabolism*; D010743:Phospholipids / Q000378:metabolism*; D011108:Polymers / Q000378:metabolism; D011145:Polyvinyls / Q000378:metabolism*
D010743:Phospholipids; D011108:Polymers; D011145:Polyvinyls; D003576:Electron Transport Complex IV