Electrooptic study of the deionized form of bacteriorhodopsin |
| |
| Authors: | S G Taneva G Todorov I B Petkanchin S P Stoylov |
| |
| Institution: | (1) Institute of Physical Chemistry, Bulgarian Academy of Sciences, BG-1040 Sofia, Bulgaria;(2) Central Laboratory of Biophysics, Bulgarian Academy of Sciences, BG-1113 Sofia, Bulgaria;(3) Department of Physics and Biophysics, Medical Academy, BG-1431 Sofia, Bulgaria |
| |
| Abstract: | Electric field induced light scattering by suspensions of cation-depleted purple membranes, obtained by deionization of purple membrane (PM) suspensions on a cation exchange column or by electrodialysis at a pH around 6, shows a strong drop (more than 5 times) in the value of the permanent dipole moment relative to that of PM fragments. The membrane dipole moments were measured both at low dc and ac electric fields as well as by using electric field pulses with reversing polarity. Some slight changes in the dispersion of the electric polarizability were also observed.Microelectrophoretic measurements showed that the electric charge of the membrane fragments is increased by 30% after deionization. The importance of these data for the understanding of the blue membrane properties and subsequently for the mechanism of proton pumping are discussed. |
| |
| Keywords: | Bacteriorhodopsin purple membrane blue membrane electric light scattering permanent dipole moment electric polarizability electric charge |
| 本文献已被 SpringerLink 等数据库收录！ |
|
