Journal Article/Review

FZJ-2015-07498

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png ESR — A retinal protein with unusual properties from Exiguobacterium sibiricum

Petrovskaya, L. E. (Corresponding author) ; Balashov, S. P. ; Lukashev, E. P. ; Imasheva, E. S. ; Gushchin, I.FZJ* ; Dioumaev, A. K. ; Rubin, A. B. ; Dolgikh, D. A. ; Gordeliy, V.FZJ* ; Lanyi, J. K. ; Kirpichnikov, M. P.

2015
Springer Science + Business Media B.V Dordrecht [u.a.]

This record in other databases:  

Please use a persistent id in citations: doi:10.1134/S000629791506005X

Abstract: This review covers the properties of a retinal protein (ESR) from the psychrotrophic bacterium Exiguobacterium sibiricum that functions as a light-driven proton pump. The presence of a lysine residue at the position corresponding to intramolecular proton donor for the Schiff base represents a unique structural feature of ESR. We have shown that Lys96 successfully facilitates delivery of protons from the cytoplasmic surface to the Schiff base, thus acting as a proton donor in ESR. Since proton uptake during the photocycle precedes Schiff base reprotonation, we conclude that this residue is initially in the uncharged state and acquires a proton for a short time after Schiff base deprotonation and M intermediate formation. Involvement of Lys as a proton donor distinguishes ESR from the related retinal proteins — bacteriorhodopsin (BR), proteorhodopsin (PR), and xanthorhodopsin (XR), in which the donor function is performed by residues with a carboxyl side chain. Like other eubacterial proton pumps (PR and XR), ESR contains a histidine residue interacting with the proton acceptor Asp85. In contrast to PR, this interaction leads to shift of the acceptor’s pK a to more acidic pH, thus providing its ability to function over a wide pH range. The presence of a strong H-bond between Asp85 and His57, the structure of the proton-conducting pathways from cytoplasmic surface to the Schiff base and to extracellular surface, and other properties of ESR were demonstrated by solving its three-dimensional structure, which revealed several differences from known structures of BR and XR. The structure of ESR, its photocycle, and proton transfer reactions are discussed in comparison with homologous retinal proteins.

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Contributing Institute(s):

1. Strukturbiochemie (ICS-6)

Research Program(s):

1. 551 - Functional Macromolecules and Complexes (POF3-551) (POF3-551)

Appears in the scientific report 2015

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Database coverage:
; BIOSIS Previews ; Current Contents - Life Sciences ; IF < 5 ; JCR ; NCBI Molecular Biology Database ; SCOPUS ; Science Citation Index ; Science Citation Index Expanded ; Thomson Reuters Master Journal List ; Web of Science Core Collection

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