TY  - JOUR
AU  - Gushchin, Ivan
AU  - Chervakov, Pavel
AU  - Kuzmichev, Pavel
AU  - Popov, Alexander N
AU  - Round, Ekaterina
AU  - Borshchevskiy, Valentin
AU  - Ishchenko, Andrii
AU  - Petrovskaya, Lada
AU  - Chupin, Vladimir
AU  - Dolgikh, Dmitry A
AU  - Arseniev, Alexander S
AU  - Arseniev, Alexander A
AU  - Kirpichnikov, Mikhail
AU  - Gordeliy, Valentin
TI  - Structural insights into the proton pumping by unusual proteorhodopsin from nonmarine bacteria
JO  - Proceedings of the National Academy of Sciences of the United States of America
VL  - 110
IS  - 31
SN  - 1091-6490
CY  - Washington, DC
PB  - National Acad. of Sciences
M1  - FZJ-2015-04393
SP  - 12631 - 12636
PY  - 2013
AB  - Light-driven proton pumps are present in many organisms. Here, we present a high-resolution structure of a proteorhodopsin from a permafrost bacterium, Exiguobacterium sibiricum rhodopsin (ESR). Contrary to the proton pumps of known structure, ESR possesses three unique features. First, ESR's proton donor is a lysine side chain that is situated very close to the bulk solvent. Second, the α-helical structure in the middle of the helix F is replaced by 3(10)- and π-helix-like elements that are stabilized by the Trp-154 and Asn-224 side chains. This feature is characteristic for the proteorhodopsin family of proteins. Third, the proton release region is connected to the bulk solvent by a chain of water molecules already in the ground state. Despite these peculiarities, the positions of water molecule and amino acid side chains in the immediate Schiff base vicinity are very well conserved. These features make ESR a very unusual proton pump. The presented structure sheds light on the large family of proteorhodopsins, for which structural information was not available previously.
KW  - Bacterial Proteins (NLM Chemicals)
KW  - proteorhodopsin (NLM Chemicals)
KW  - Rhodopsin (NLM Chemicals)
LB  - PUB:(DE-HGF)16
C6  - pmid:23872846
C2  - pmc:PMC3732926
UR  - <Go to ISI:>//WOS:000322441500040
DO  - DOI:10.1073/pnas.1221629110
UR  - https://juser.fz-juelich.de/record/202104
ER  -