Photoelectric signals of membrane proteins
We discovered that the purple membrane fragments can be oriented in electric field (because the membrane fragments
have a large permanent electric dipole moment, due to the fact that the Bacteriorhodopsin molecules are perfectly
oriented in them).
Click on the image to play the movie.
L. Keszthelyi, Orientation of membrane fragments by electric field, Biochim. Biophys. Acta 598(3) 429 (1980)