Asymmetric protonation of EmrE
نویسندگان
چکیده
منابع مشابه
Asymmetric protonation of EmrE.
The small multidrug resistance transporter EmrE is a homodimer that uses energy provided by the proton motive force to drive the efflux of drug substrates. The pKa values of its "active-site" residues--glutamate 14 (Glu14) from each subunit--must be poised around physiological pH values to efficiently couple proton import to drug export in vivo. To assess the protonation of EmrE, pH titrations ...
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The small multidrug transporter from Escherichia coli, EmrE, couples the energetically uphill extrusion of hydrophobic cations out of the cell to the transport of two protons down their electrochemical gradient. Although principal mechanistic elements of proton/substrate antiport have been described, the structural record is limited to the conformation of the substrate-bound state, which has be...
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Secondary active transport proteins play a central role in conferring bacterial multidrug resistance. In this work, we investigated the proton-coupled transport mechanism for the Escherichia coli drug efflux pump EmrE using NMR spectroscopy. Our results show that the global conformational motions necessary for transport are modulated in an allosteric fashion by the protonation state of a membra...
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ژورنال
عنوان ژورنال: Journal of General Physiology
سال: 2015
ISSN: 1540-7748,0022-1295
DOI: 10.1085/jgp.201511404