Linked Life Data

20036636

Source:http://linkedlifedata.com/resource/pubmed/id/20036636

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2010-2-23
pubmed:abstractText
Escherichia coli multidrug resistance protein E (EmrE) is a four transmembrane alpha-helix protein, and a member of the small multidrug resistance protein family that confers resistance to a broad range of quaternary cation compounds (QCC) via proton motive force. The multimeric states of EmrE protein during transport or ligand binding are variable and specific to the conditions of study. To explore EmrE multimerization further, EmrE extracted from E. coli membranes was solubilized in anionic detergent, sodium dodecyl sulphate (SDS), at varying protein concentrations. At low concentrations (</=1muM) in SDS-EmrE is monomeric, but upon increasing EmrE concentration, a variety of multimeric states can be observed by SDS-Tricine polyacrylamide gel electrophoresis (PAGE). Addition of the (QCC), tetraphenyl phosphonium (TPP), to SDS-EmrE samples enhanced EmrE multimer formation using SDS-Tricine PAGE. The relative shapes of EmrE multimers in SDS with or without TPP addition were determined by small angle neutron scattering (SANS) analysis and revealed that EmrE dimers altered in conformation depending on the SDS concentration. SANS analysis also revealed that relative shapes of larger EmrE multimers (>/=100nm sizes) altered in the presence of TPP. Circular dichroism spectropolarimetry displayed no differences in secondary structure under the conditions studied. Fluorescence spectroscopy of SDS-EmrE protein demonstrated that aromatic residues, Trp and Tyr, are more susceptible to SDS concentration than TPP addition, but both residues exhibit enhanced quenching at high ligand concentrations. Hence, EmrE forms various multimers in SDS that are influenced by detergent concentration and TPP substrate addition.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0006-3002
pubmed:author
pubmed:copyrightInfo
Copyright 2009 Elsevier B.V. All rights reserved.
pubmed:issnType
Print
pubmed:volume
1798
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
526-35
pubmed:meshHeading
pubmed-meshheading:20036636-Antiporters, pubmed-meshheading:20036636-Circular Dichroism, pubmed-meshheading:20036636-Detergents, pubmed-meshheading:20036636-Electrophoresis, Polyacrylamide Gel, pubmed-meshheading:20036636-Escherichia coli, pubmed-meshheading:20036636-Escherichia coli Proteins, pubmed-meshheading:20036636-Models, Molecular, pubmed-meshheading:20036636-Multidrug Resistance-Associated Proteins, pubmed-meshheading:20036636-Neutron Diffraction, pubmed-meshheading:20036636-Onium Compounds, pubmed-meshheading:20036636-Organophosphorus Compounds, pubmed-meshheading:20036636-Protein Multimerization, pubmed-meshheading:20036636-Protein Structure, Secondary, pubmed-meshheading:20036636-Scattering, Small Angle, pubmed-meshheading:20036636-Sodium Dodecyl Sulfate, pubmed-meshheading:20036636-Solubility, pubmed-meshheading:20036636-Solutions, pubmed-meshheading:20036636-Spectrometry, Fluorescence
pubmed:year
2010
pubmed:articleTitle
Multimeric forms of the small multidrug resistance protein EmrE in anionic detergent.
pubmed:affiliation
Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't