Photo-induced potentials across a polymer stabilized planar membrane, in the presence of bacteriorhodopsin
Black lipid planar membranes were prepared by incorporating polymers such as polystyrene in a membrane forming solution. The polymer-incorporated planar membranes showed greater stability to applied electric fields and have longer lifetimes. Photopotentials were studied under several conditions: with bacteriorhodopsin in the planar membrane; with bacteriorhodopsin in liposomes; with bacteriorhodopsin fragments in suspension; and with bacteriorhodopsin both in the planar membrane and in liposomes. Skulachev's laboratory has reported that bacteriorhodopsin-liposomes develop potentials across a black lipid planar membrane. In our studies, because the polymer incorporated planar membranes are very stable, it was possible to obtain somewhat larger photopotentials in the presence of bacteriorhodopsin ranging between 30-500 mV. The enhancement of bacteriorhodopsin catalyzed photopotentials, found in the presence of Ca/sup + +/ (or other bivalent cations) and/or applied electric fields, appeared to result from an orientation effect of bacteriorhodopsin at the membrane interface.
- Research Organization:
- Univ. of California, Berkeley
- OSTI ID:
- 7141810
- Journal Information:
- Biochem. Biophys. Res. Commun.; (United States), Vol. 71:2
- Country of Publication:
- United States
- Language:
- English
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