Mechanism of pH-dependent activation of the sodium-proton antiporter NhaA
Data(s) |
06/07/2016
06/07/2016
2016
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Resumo |
Data files to accompany the article in Nature Communications, in press. Escherichia coli NhaA is a prototype sodium-proton antiporter, which has been extensively characterized by X-ray crystallography, biochemical and biophysical experiments. However, the identities of proton carriers and details of pH-regulated mechanism remain controversial. Here we report constant pH molecular dynamics data, which reveal that NhaA activation involves a net charge switch of a pH sensor at the entrance of the cytoplasmic funnel and opening of a hydrophobic gate at the end of the funnel. The latter is triggered by charging of Asp164, the first proton carrier. The second proton carrier Lys300 forms a salt bridge with Asp163 in the inactive state, and releases a proton when a sodium ion binds Asp163. These data reconcile current models and illustrate the power of state-of-the-art molecular dynamics simulations in providing atomic details of proton-coupled transport across membrane, which is challenging to elucidate by experimental techniques. |
Identificador |
doi:10.13016/M2VZ1F |
Idioma(s) |
en_US |
Relação |
A. James Clark School of Engineering Fischell Department of Bioengineering Digital Repository at the University of Maryland University of Maryland (College Park, MD) |
Tipo |
Dataset |