Structural evidence for induced fit and a mechanism for sugar/H+ symport in LacY.
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ABSTRACT:
SUBMITTER: Mirza O
PROVIDER: S-EPMC1422171 | biostudies-literature | 2006 Mar
REPOSITORIES: biostudies-literature
Publications
Structural evidence for induced fit and a mechanism for sugar/H+ symport in LacY.
Mirza Osman O Guan Lan L Verner Gill G Iwata So S Kaback H Ronald HR
The EMBO journal 20060309 6
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 indu ...[more]
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