Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5633
pubmed:dateCreated
2003-8-1
pubmed:databankReference
pubmed:abstractText
Membrane transport proteins that transduce free energy stored in electrochemical ion gradients into a concentration gradient are a major class of membrane proteins. We report the crystal structure at 3.5 angstroms of the Escherichia coli lactose permease, an intensively studied member of the major facilitator superfamily of transporters. The molecule is composed of N- and C-terminal domains, each with six transmembrane helices, symmetrically positioned within the permease. A large internal hydrophilic cavity open to the cytoplasmic side represents the inward-facing conformation of the transporter. The structure with a bound lactose homolog, beta-D-galactopyranosyl-1-thio-beta-D-galactopyranoside, reveals the sugar-binding site in the cavity, and residues that play major roles in substrate recognition and proton translocation are identified. We propose a possible mechanism for lactose/proton symport (co-transport) consistent with both the structure and a large body of experimental data.
pubmed:grant
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
1095-9203
pubmed:author
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
301
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
610-5
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed-meshheading:12893935-Amino Acid Substitution, pubmed-meshheading:12893935-Binding Sites, pubmed-meshheading:12893935-Biological Transport, pubmed-meshheading:12893935-Cell Membrane, pubmed-meshheading:12893935-Crystallization, pubmed-meshheading:12893935-Crystallography, X-Ray, pubmed-meshheading:12893935-Escherichia coli, pubmed-meshheading:12893935-Escherichia coli Proteins, pubmed-meshheading:12893935-Hydrogen Bonding, pubmed-meshheading:12893935-Hydrophobic and Hydrophilic Interactions, pubmed-meshheading:12893935-Ion Transport, pubmed-meshheading:12893935-Lactose, pubmed-meshheading:12893935-Membrane Transport Proteins, pubmed-meshheading:12893935-Models, Molecular, pubmed-meshheading:12893935-Monosaccharide Transport Proteins, pubmed-meshheading:12893935-Mutation, pubmed-meshheading:12893935-Protein Conformation, pubmed-meshheading:12893935-Protein Structure, Secondary, pubmed-meshheading:12893935-Protein Structure, Tertiary, pubmed-meshheading:12893935-Protons, pubmed-meshheading:12893935-Substrate Specificity, pubmed-meshheading:12893935-Symporters, pubmed-meshheading:12893935-Thiogalactosides
pubmed:year
2003
pubmed:articleTitle
Structure and mechanism of the lactose permease of Escherichia coli.
pubmed:affiliation
Department of Biological Sciences, Imperial College London, London SW7 2AZ, UK.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't