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Advances in Solid-State NMR Studies of Microbial Rhodopsins

Reference work entry

Abstract

Microbial rhodopsins are membrane-embedded heptahelical proteins which are responsible for ion transport or signal transduction in cells. Whereas initial research focused on the four microbial rhodopsins found in Halobacterium Salinarium and related haloarchaea, many additional members have been recently discovered in eubacteria and eukarya, and their structures and functions have been extensively studied. Solid-state nuclear magnetic resonance (NMR) spectroscopy is unique among structural and biophysical methods in that it reports on a structure of a membrane protein in its native-like lipid-embedded state. Here we review the developments in solid-state NMR and highlight its recent contributions to the structural studies of microbial rhodopsins.

Keywords

Seven-helical membrane proteins Microbial rhodopsins Protein structure Protein dynamics Oligomerization Ion transport Photosensors Bacteriorhodopsin Proteorhodopsin Sensory rhodopsin I Sensory rhodopsin II Anabaena sensory rhodopsin Channelrhodopsin Solid-state NMR Magic angle spinning Dynamic nuclear polarization 

Notes

Acknowledgments

This work was supported by NSERC Discovery grant to V.L. We thank Dr. M. Baldus for providing us with high-resolution figures for this review.

Glossary

ASR

Anabaena Sensory Rhodopsin

ASRT

Anabaena Sensory Rhodopsin Transducer

BR

Bacteriorhodopsin

ChR1

Channelrhodopsin 1

ChR2

Channelrhodopsin 2

DMPA

1,2-dimyristoyl-sn-glycero-3-phosphate

DMPC

1,2-dimyristoyl-sn-glycero-3-phosphocholine

DOPC

1,2-dioleoyl-sn-glycero-3-phosphocholine

GPR

Green Proteorhodopsin

MAS

Magic Angle Spinning

NMR

Nuclear Magnetic Resonance

PRE

Paramagnetic Relaxation Enhancement

SRI

Sensory Rhodopsin I

SRII

Sensory Rhodopsin II

7TM

Seven-Helical

SSNMR

Solid-state NMR

TEDOR

Transferred Echo Double Resonance

TM

Transmembrane

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© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Physics and Biophysics Interdepartmental GroupUniversity of GuelphGuelphCanada

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