TY  - JOUR
A1  - Weissbecker, Juliane
A1  - Boumrifak, Chokri
A1  - Breyer, Maximilian
A1  - Wießalla, Tristan
A1  - Shevchenko, Vitaly
A1  - Mager, Thomas
A1  - Slavov, Chavdar
A1  - Alekseev, Alexey
A1  - Kovalev, Kirill
A1  - Gordeliy, Valentin
A1  - Bamberg, Ernst
A1  - Wachtveitl, Josef
T1  - The voltage dependent sidedness of the reprotonation of the retinal schiff base determines the unique inward pumping of xenorhodopsin
T2  - Angewandte Chemie
N2  - The new class of microbial rhodopsins, called xenorhodopsins (XeRs),[1] extends the versatility of this family by inward H+ pumps.[2–4] These pumps are an alternative optogenetic tool to the light-gated ion channels (e.g. ChR1,2), because the activation of electrically excitable cells by XeRs is independent from the surrounding physiological conditions. In this work we functionally and spectroscopically characterized XeR from Nanosalina (NsXeR).[1] The photodynamic behavior of NsXeR was investigated on the ps to s time scale elucidating the formation of the J and K and a previously unknown long-lived intermediate. The pH dependent kinetics reveal that alkalization of the surrounding medium accelerates the photocycle and the pump turnover. In patch-clamp experiments the blue-light illumination of NsXeR in the M state shows a potential-dependent vectoriality of the photocurrent transients, suggesting a variable accessibility of reprotonation of the retinal Schiff base. Insights on the kinetically independent switching mechanism could furthermore be obtained by mutational studies on the putative intracellular H+ acceptor D220.
KW  - accessibility switch
KW  - inward proton pump
KW  - microbial rhodopsin
KW  - optogenetic
Y1  - 2021
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/64516
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-645163
SN  - 1521-3773
N1  - We acknowledge the Collaborative Research Center,CRC 807 “Transport and Communication across Biological Membranes” for funding. Open access funding enabled and organized by Projekt DEAL.
VL  - 60
IS  - 42
SP  - 23010
EP  - 23017
PB  - Wiley-VCH
CY  - Weinheim
ER  -