Proton uptake mechanism in bacteriorhodopsin captured by serial synchrotron crystallography.
Science
; 365(6448): 61-65, 2019 07 05.
Article
em En
| MEDLINE
| ID: mdl-31273117
ABSTRACT
Conformational dynamics are essential for proteins to function. We adapted time-resolved serial crystallography developed at x-ray lasers to visualize protein motions using synchrotrons. We recorded the structural changes in the light-driven proton-pump bacteriorhodopsin over 200 milliseconds in time. The snapshot from the first 5 milliseconds after photoactivation shows structural changes associated with proton release at a quality comparable to that of previous x-ray laser experiments. From 10 to 15 milliseconds onwards, we observe large additional structural rearrangements up to 9 angstroms on the cytoplasmic side. Rotation of leucine-93 and phenylalanine-219 opens a hydrophobic barrier, leading to the formation of a water chain connecting the intracellular aspartic acid-96 with the retinal Schiff base. The formation of this proton wire recharges the membrane pump with a proton for the next cycle.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Prótons
/
Bacteriorodopsinas
Idioma:
En
Revista:
Science
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Suíça