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2cfq
From Proteopedia
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==Overview== | ==Overview== | ||
| - | Cation-coupled active transport is an essential cellular process found | + | 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== | ==About this Structure== | ||
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[[Category: Guan, L.]] | [[Category: Guan, L.]] | ||
[[Category: Iwata, S.]] | [[Category: Iwata, S.]] | ||
| - | [[Category: Kaback, H | + | [[Category: Kaback, H R.]] |
[[Category: Mirza, O.]] | [[Category: Mirza, O.]] | ||
[[Category: Verner, G.]] | [[Category: Verner, G.]] | ||
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[[Category: transport mechanism]] | [[Category: transport mechanism]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:48:10 2008'' |
Revision as of 14:48, 21 February 2008
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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 as ligand. Known structural/functional Site: . 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 Thu Feb 21 16:48:10 2008
