@article{2c97b00a585145a1bfe97c828fccf525,
title = "Hydrogen-deuterium exchange mass spectrometry captures distinct dynamics upon substrate and inhibitor binding to a transporter",
abstract = "Proton-coupled transporters use transmembrane proton gradients to power active transport of nutrients inside the cell. High-resolution structures often fail to capture the coupling between proton and ligand binding, and conformational changes associated with transport. We combine HDX-MS with mutagenesis and MD simulations to dissect the molecular mechanism of the prototypical transporter XylE. We show that protonation of a conserved aspartate triggers conformational transition from outward-facing to inward-facing state. This transition only occurs in the presence of substrate xylose, while the inhibitor glucose locks the transporter in the outward-facing state. MD simulations corroborate the experiments by showing that only the combination of protonation and xylose binding, and not glucose, sets up the transporter for conformational switch. Overall, we demonstrate the unique ability of HDX-MS to distinguish between the conformational dynamics of inhibitor and substrate binding, and show that a specific allosteric coupling between substrate binding and protonation is a key step to initiate transport.",
author = "Ruyu Jia and Chloe Martens and Mrinal Shekhar and Shashank Pant and Pellowe, \{Grant A.\} and Lau, \{Andy M.\} and Findlay, \{Heather E.\} and Harris, \{Nicola J.\} and Emad Tajkhorshid and Booth, \{Paula J.\} and Argyris Politis",
note = "We acknowledge funding from the Leverhulme Trust (RPG-2019-178) and the Wellcome Trust (109854/Z/15/Z) to A.P., the European Research Council, ERC Advanced grant 294342 and Wellcome Trust Investigator Award 214259/Z/18/Z to P.B., as well as thank King\textbackslash{}u2019s College London for support for G.P. We also thank King\textbackslash{}u2019s College London and China Scholarship Council for providing Ph.D. studentship for R.J. This research was supported by the National Institutes of Health under awards R01-GM123455 and P41-GM104601 from the National Institute of General Medical Sciences (to E.T.). S.P. acknowledges receiving support from the Beckman Institute Graduate Fellowship. We acknowledge the computing resources provided by Blue Waters of National Center for Supercomputing Applications (award ACI-1713784 to E.T.) and by Extreme Science and Engineering Discovery Environment (XSEDE award MCA06N060 to E.T.). C.M. benefits from a \textbackslash{}u201CCharg\textbackslash{}u00E9 de Recherches\textbackslash{}u201D fellowship of the FRS-FNRS.",
year = "2020",
month = dec,
doi = "10.1038/s41467-020-20032-3",
language = "English (US)",
volume = "11",
journal = "Nature communications",
issn = "2041-1723",
publisher = "Nature Research",
number = "1",
}