Functional roles of tyrosine 185 during the bacteriorhodopsin photocycle as revealed by in situ spectroscopic studies.

Authors:
Xiaoyan Ding
Xiaoyan Ding
Institute of Biochemistry and Cell Biology
China
Chao Sun
Chao Sun
Institute of Medicinal Plant Development
China
Haolin Cui
Haolin Cui
East China Normal University
Sijin Chen
Sijin Chen
Nanfang Hospital
Yujiao Gao
Yujiao Gao
State Key Laboratory for Agrobiotechnology and Key Laboratory of Crop Heterosis and Utilization (MOE)
Yanan Yang
Yanan Yang
Mayo Clinic
Phoenix | United States
Juan Wang
Juan Wang
School of Chemistry and Chemical Engineering
China
Xiao He
Xiao He
Institute of High Energy Physics
China

Biochim Biophys Acta Bioenerg 2018 May 23. Epub 2018 May 23.

Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Materials Science, East China Normal University, Shanghai 200062, PR China. Electronic address:

Tyrosine 185 (Y185), one of the aromatic residues within the retinal (Ret) chromophore binding pocket in helix F of bacteriorhodopsin (bR), is highly conserved among the microbial rhodopsin family proteins. Many studies have investigated the functions of Y185, but its underlying mechanism during the bR photocycle remains unclear. To address this research gap, in situ two-dimensional (2D) magic-angle spinning (MAS) solid-state NMR (ssNMR) of specifically labelled bR, combined with light-induced transient absorption change measurements, dynamic light scattering (DLS) measurements, titration analysis and site-directed mutagenesis, was used to elucidate the functional roles of Y185 during the bR photocycle in the native membrane environment. Different interaction modes were identified between Y185 and the Ret chromophore in the dark-adapted (inactive) state and M (active) state, indicating that Y185 may serve as a rotamer switch maintaining the protein dynamics, and plays an important role in the efficient proton-pumping mechanism in the bR purple membrane.

Download full-text PDF

Source
https://linkinghub.elsevier.com/retrieve/pii/S00052728183012
Publisher Site
http://dx.doi.org/10.1016/j.bbabio.2018.05.011DOI Listing

Still can't find the full text of the article?

We can help you send a request to the authors directly.
May 2018
26 Reads

Publication Analysis

Top Keywords

tyrosine 185
8
ret chromophore
8
functional roles
8
y185
5
light scattering
4
scattering dls
4
dynamic light
4
measurements dynamic
4
change measurements
4
dls measurements
4
titration analysis
4
elucidate functional
4
roles y185
4
mutagenesis elucidate
4
site-directed mutagenesis
4
absorption change
4
analysis site-directed
4
measurements titration
4
transient absorption
4
two-dimensional magic-angle
4

Similar Publications