7CLJ

Crystal structure of Thermoplasmatales archaeon heliorhodopsin E108D mutant

7CLJ の概要

• エントリーDOI: 10.2210/pdb7clj/pdb
• 分子名称: heliorhodopsin, RETINAL, (2R)-2,3-dihydroxypropyl (9Z)-octadec-9-enoate, ... (5 entities in total)
• 機能のキーワード: alpha-helical, membrane protein
• 由来する生物種: Thermoplasmatales archaeon SG8-52-1
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 35600.87

構造登録者

Tanaka, T.,Shihoya, W.,Yamashita, K.,Nureki, O. (登録日: 2020-07-21, 公開日: 2020-09-02, 最終更新日: 2024-10-09)

主引用文献

Tanaka, T.,Singh, M.,Shihoya, W.,Yamashita, K.,Kandori, H.,Nureki, O.
Structural basis for unique color tuning mechanism in heliorhodopsin.
Biochem.Biophys.Res.Commun., 533:262-267, 2020

PubMed Abstract: Microbial rhodopsins comprise an opsin protein with seven transmembrane helices and a retinal as the chromophore. An all-trans retinal is covalently bonded to a lysine residue through the retinal Schiff base (RSB) and stabilized by a negatively charged counterion. The distance between the RSB and counterion is closely related to the light energy absorption. However, in heliorhodopsin-48C12 (HeR-48C12), while E107 acts as the counterion, E107D mutation exhibits an identical absorption spectrum to the wild-type, suggesting that the distance does not affect its absorption spectra. Here we present the 2.6 Å resolution crystal structure of the Thermoplasmatales archaeon HeR E108D mutant, which also has an identical absorption spectrum to the wild-type. The structure revealed that D108 does not form a hydrogen bond with the RSB, and its counterion interaction becomes weaker. Alternatively, the serine cluster, S78, S112, and S238 form a distinct interaction network around the RSB. The absorption spectra of the E to D and S to A double mutants suggested that S112 influences the spectral shift by compensating for the weaker counterion interaction. Our structural and spectral studies have revealed the unique spectral shift mechanism of HeR and clarified the physicochemical properties of HeRs.

PubMed: 32951839
DOI: 10.1016/j.bbrc.2020.06.124

実験手法

X-RAY DIFFRACTION (2.6 Å)