Open Access19F Paramagnetic Relaxation-Based NMR for Quaternary Structural Restraints of Ion Channels
Author(s) -
Vasyl Bondarenko,
Marta M. Wells,
Qiang Chen,
Kevin Singewald,
Sunil Saxena,
Yan Xu,
Pei Tang
Publication year - 2019
Publication title -
acs chemical biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.899
H-Index - 111
eISSN - 1554-8937
pISSN - 1554-8929
DOI - 10.1021/acschembio.9b00692
Subject(s) - fluorine 19 nmr , relaxation (psychology) , electron paramagnetic resonance , chemistry , paramagnetism , protein quaternary structure , nuclear magnetic resonance , ion , crystallography , nuclear magnetic resonance spectroscopy , micelle , stereochemistry , physics , protein subunit , condensed matter physics , organic chemistry , psychology , social psychology , biochemistry , aqueous solution , gene
Quaternary distance restraints are essential to define the three-dimensional structures of protein assemblies. These distances often fall within a range of 10-18 Å, which challenges the high and low measurement limits of conventional nuclear magnetic resonance (NMR) and double electron-electron resonance electron spin resonance spectroscopies. Here, we report the use of 19 F paramagnetic relaxation enhancement (PRE) NMR in combination with 19 F/paramagnetic labeling to equivalent sites in different subunits of a protein complex in micelles to determine intersubunit distances. The feasibility of this strategy was evaluated on a pentameric ligand-gated ion channel, for which we found excellent agreement of the 19 F PRE NMR results with previous structural information. The study suggests that 19 F PRE NMR is a viable tool in extracting distance restraints to define quaternary structures.