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2cfq
From Proteopedia
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SUGAR FREE LACTOSE PERMEASE AT NEUTRAL PH
Overview
Cation-coupled active transport is an essential cellular process found, ubiquitously in all living organisms. Here, we present two novel, ligand-free X-ray structures of the lactose permease (LacY) of Escherichia, coli determined at acidic and neutral pH, and propose a model for the, mechanism of coupling between lactose and H+ translocation. No, sugar-binding site is observed in the absence of ligand, and deprotonation, of the key residue Glu269 is associated with ligand binding. Thus, substrate induces formation of the sugar-binding site, as well as the, initial step in H+ transduction.
About this Structure
2CFQ is a [Single protein] structure of sequence from [Escherichia coli] with HG as [ligand]. Structure known Active Site: AC1. Full crystallographic information is available from [OCA].
Reference
Structural evidence for induced fit and a mechanism for sugar/H+ symport in LacY., Mirza O, Guan L, Verner G, Iwata S, Kaback HR, EMBO J. 2006 Mar 22;25(6):1177-83. Epub 2006 Mar 9. PMID:16525509
Page seeded by OCA on Tue Oct 30 08:36:16 2007
