2CFP

Sugar Free Lactose Permease at acidic pH

Summary for 2CFP

• Entry DOI: 10.2210/pdb2cfp/pdb
• Related: 1M2U 1PV6 1PV7 2CFQ
• Descriptor: LACTOSE PERMEASE, MERCURY (II) ION (2 entities in total)
• Functional Keywords: transport, lactose permease, transport mechanism, lactose/h+ symport, sugar transport, transmembrane, formylation
• Biological source: ESCHERICHIA COLI
• Cellular location: Cell inner membrane; Multi-pass membrane protein: P02920
• Total number of polymer chains: 1
• Total formula weight: 47487.75

Authors

Mirza, O.,Guan, L.,Verner, G.,Iwata, S.,Kaback, H.R. (deposition date: 2006-02-22, release date: 2006-03-13, Last modification date: 2023-12-13)

Primary citation

Mirza, O.,Guan, L.,Verner, G.,Iwata, S.,Kaback, H.R.
Structural Evidence for Induced Fit and a Mechanism for Sugar/H(+) Symport in Lacy.
Embo J., 25:2038-, 2006

PubMed Abstract: 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.

PubMed: 16525509
DOI: 10.1038/SJ.EMBOJ.7601028

Experimental method

X-RAY DIFFRACTION (3.3 Å)