Abstract
The translational and rotational electrokinetics of the anesthetic-induced spectral transitions bR568 → bR480 → bR380 of bacteriorhodopsin have been investigated. Formation of the bR480 form is associated with an increase of the purple membrane negative electrokinetic charge, while the transformation of bR480 into bR380 is accompanied by a decrease of the membrane negative charge as compared to that of the 480 nm-absorbing form. Removal of anesthetics leads to the back transitions bR480 → bR568 and (in part) bR380 → bR568; however, the electrokinetic charge of the native membranes is not restored. A strong decrease in the electric y polarizability and the appearance of a slow polarizability component are also observed in anesthetic-treated membranes. Comparison with the electrokinetic behaviour of partially delipidated membranes and with that of liposomes composed of purple membrane total lipids suggests that: (i) anesthetic molecules partition mainly at the protein/lipid interface inducing irreversible rearrangement of the boundary lipid layer, and (ii) different mode(s) or site(s) of interaction are responsible for the spectral and surface charge effects. The data are compatible with the hypothesis of anesthetics acting through partial dehydration of the membrane surface.
| Original language | English |
|---|---|
| Pages (from-to) | 331-337 |
| Number of pages | 7 |
| Journal | BBA - Biomembranes |
| Volume | 1236 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - Jun 14 1995 |
| Externally published | Yes |
Fingerprint
All Science Journal Classification (ASJC) codes
- Biophysics
- Biochemistry
- Cell Biology
Cite this
Electrokinetic charge of the anesthetic-induced bR480 and bR380 spectral forms of bacteriorhodopsin. / Taneva, Stefka G.; Caaveiro, JoséM M.M.; Petkanchin, Ivana B.; Goñi, Félix M.
In: BBA - Biomembranes, Vol. 1236, No. 2, 14.06.1995, p. 331-337.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Electrokinetic charge of the anesthetic-induced bR480 and bR380 spectral forms of bacteriorhodopsin
AU - Taneva, Stefka G.
AU - Caaveiro, JoséM M.M.
AU - Petkanchin, Ivana B.
AU - Goñi, Félix M.
PY - 1995/6/14
Y1 - 1995/6/14
N2 - The translational and rotational electrokinetics of the anesthetic-induced spectral transitions bR568 → bR480 → bR380 of bacteriorhodopsin have been investigated. Formation of the bR480 form is associated with an increase of the purple membrane negative electrokinetic charge, while the transformation of bR480 into bR380 is accompanied by a decrease of the membrane negative charge as compared to that of the 480 nm-absorbing form. Removal of anesthetics leads to the back transitions bR480 → bR568 and (in part) bR380 → bR568; however, the electrokinetic charge of the native membranes is not restored. A strong decrease in the electric y polarizability and the appearance of a slow polarizability component are also observed in anesthetic-treated membranes. Comparison with the electrokinetic behaviour of partially delipidated membranes and with that of liposomes composed of purple membrane total lipids suggests that: (i) anesthetic molecules partition mainly at the protein/lipid interface inducing irreversible rearrangement of the boundary lipid layer, and (ii) different mode(s) or site(s) of interaction are responsible for the spectral and surface charge effects. The data are compatible with the hypothesis of anesthetics acting through partial dehydration of the membrane surface.
AB - The translational and rotational electrokinetics of the anesthetic-induced spectral transitions bR568 → bR480 → bR380 of bacteriorhodopsin have been investigated. Formation of the bR480 form is associated with an increase of the purple membrane negative electrokinetic charge, while the transformation of bR480 into bR380 is accompanied by a decrease of the membrane negative charge as compared to that of the 480 nm-absorbing form. Removal of anesthetics leads to the back transitions bR480 → bR568 and (in part) bR380 → bR568; however, the electrokinetic charge of the native membranes is not restored. A strong decrease in the electric y polarizability and the appearance of a slow polarizability component are also observed in anesthetic-treated membranes. Comparison with the electrokinetic behaviour of partially delipidated membranes and with that of liposomes composed of purple membrane total lipids suggests that: (i) anesthetic molecules partition mainly at the protein/lipid interface inducing irreversible rearrangement of the boundary lipid layer, and (ii) different mode(s) or site(s) of interaction are responsible for the spectral and surface charge effects. The data are compatible with the hypothesis of anesthetics acting through partial dehydration of the membrane surface.
UR - http://www.scopus.com/inward/record.url?scp=0029028170&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0029028170&partnerID=8YFLogxK
U2 - 10.1016/0005-2736(95)00074-D
DO - 10.1016/0005-2736(95)00074-D
M3 - Article
C2 - 7794973
AN - SCOPUS:0029028170
VL - 1236
SP - 331
EP - 337
JO - Biochimica et Biophysica Acta - Biomembranes
JF - Biochimica et Biophysica Acta - Biomembranes
SN - 0005-2736
IS - 2
ER -