A triarylmethyl spin label for long-range distance measurement at physiological temperatures using T-1 relaxation enhancement

A triarylmethyl spin label for long-range distance measurement at physiological temperatures using T-1 relaxation enhancement Full article

Journal

Journal of Magnetic Resonance
ISSN: 1090-7807

Output data

Year: 2016, Volume: 269, Pages: 50-54 Pages count : 5 DOI: 10.1016/j.jmr.2016.05.006

Tags

Triarylmethyl radical; Spin labeling; Saturation recovery; Distance measurement at physiological temperature; Relaxation enhancement

Authors

Yang Zhongyu ^1,2,6 , Bridges Michael D. ^1,2 , Lopez Carlos J. ^1,2 , Rogozhnikova Olga Yu. ^3,4 , Trukhin Dmitry V. ^3,4 , Brooks Evan K. ^1,2 , Tormyshev Victor ^3,4 , Halpern Howard J. ⁵ , Hubbell Wayne L. ^1,2

Affiliations

1	(Данные Web of science) Univ Calif Los Angeles, Jules Stein Eye Inst, Los Angeles, CA 90095 USA
2	(Данные Web of science) Univ Calif Los Angeles, Dept Chem & Biochem, Los Angeles, CA 90095 USA
3	(Данные Web of science) NN Vorozhtsov Novosibirsk Inst Organ Chem, Novosibirsk 630090, Russia
4	(Данные Web of science) Novosibirsk State Univ, Novosibirsk 630090, Russia
5	(Данные Web of science) Univ Chicago, Ctr EPR Imaging Vivo Physiol, Dept Radiat & Cellular Oncol, Chicago, IL 60637 USA
6	(Данные Web of science) North Dakota State Univ, Dept Chem & Biochem, Fargo, ND 58102 USA

Site-directed spin labeling (SDSL) in combination with electron paramagnetic resonance (EPR) spectroscopy has become an important tool for measuring distances in proteins on the order of a few nm. For this purpose pairs of spin labels, most commonly nitroxides, are site-selectively introduced into the protein. Recent efforts to develop new spin labels are focused on tailoring the intrinsic properties of the label to either extend the upper limit of measurable distances at physiological temperature, or to provide a unique spectral lineshape so that selective pairwise distances can be measured in a protein or complex containing multiple spin label species. Triarylmethyl (TAM) radicals are the foundation for a new class of spin labels that promise to provide both capabilities. Here we report a new methanethiosulfonate derivative of a TAM radical that reacts rapidly and selectively with an engineered cysteine residue to generate a TAM containing side chain (TAM1) in high yield. With a TAM1 residue and Cu2+ bound to an engineered Cu2+ binding site, enhanced T-1 relaxation of TAM should enable measurement of interspin distances up to 50 A at physiological temperature. To achieve favorable TAM1-labeled protein concentrations without aggregation, proteins are tethered to a solid support either site-selectively using an unnatural amino acid or via native lysine residues. The methodology is general and readily extendable to complex systems, including membrane proteins. (C) 2016 Elsevier Inc. All rights reserved.

Yang Z. , Bridges M.D. , Lopez C.J. , Rogozhnikova O.Y. , Trukhin D.V. , Brooks E.K. , Tormyshev V. , Halpern H.J. , Hubbell W.L.
A triarylmethyl spin label for long-range distance measurement at physiological temperatures using T-1 relaxation enhancement

Journal of Magnetic Resonance. 2016. V.269. P.50-54. DOI: 10.1016/j.jmr.2016.05.006 WOS Scopus РИНЦ

Full text from publisher

Published print:

Aug 1, 2016

Web of science	WOS:000381239900005
Scopus	2-s2.0-84971283593
Elibrary	27048925
OpenAlex	W2389594097