Electric response of a back photoreaction in the bacteriorhodopsin photocycle.
Biophys J
; 31(2): 207-13, 1980 Aug.
Article
em En
| MEDLINE
| ID: mdl-6266533
ABSTRACT
The electric response of a back photoreaction in the bacteriorhodopsin photocycle was investigated. The proton pumping activity of green flash excited bacteriorhodopsin stops if the M412 form is illuminated by blue light (Karvaly and Dancsházy, 1977). In the present work a fast negative displacement current signal was measured in an oriented membrane suspension system, indicative of back movement of protons from M412 to BR570. Quantitative evaluation of the data shows that there are at least two steps in the back reaction, with different rate constants. The temperature dependence of the rate constants show simple linear Arrhenius behavior between 5 degree and 40 degree C. The rate constants were slower by a factor of 1.8 in D2O suspension. The relevance of the protein electric response signals (PERS) observed in this paper to the early receptor potential is discussed.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Bacteriorodopsinas
/
Carotenoides
/
Lasers
Idioma:
En
Revista:
Biophys J
Ano de publicação:
1980
Tipo de documento:
Article