RRC ID 35453
著者 Holdsworth SR, Law CJ.
タイトル Functional and biochemical characterisation of the Escherichia coli major facilitator superfamily multidrug transporter MdtM.
ジャーナル Biochimie
Abstract Multidrug resistance (MDR) occurs when bacteria simultaneously acquire resistance to a broad spectrum of structurally dissimilar compounds to which they have not previously been exposed. MDR is principally a consequence of the active transport of drugs out of the cell by proteins that are integral membrane transporters. We characterised and purified the putative Escherichia coli MDR transporter, MdtM, a 410 amino acid residue protein that belongs to the large and ubiquitous major facilitator superfamily. Functional characterisation of MdtM using growth inhibition and whole cell transport assays revealed its role in intrinsic resistance of E. coli cells to the antimicrobials ethidium bromide and chloramphenicol. Site-directed mutagenesis studies implied that the MdtM aspartate 22 residue and the highly conserved arginine at position 108 play a role in proton recognition. MdtM was homologously overexpressed and purified to homogeneity in dodecyl-β-D-maltopyranoside detergent solution and the oligomeric state and stability of the protein in a variety of detergent solutions was investigated using size-exclusion HPLC. Purified MdtM is monomeric and stable in dodecyl-β-D-maltopyranoside solution and binds chloramphenicol with nanomolar affinity in the same detergent. This work provides a firm foundation for structural studies on this class of multidrug transporter protein.
巻・号 94(6)
ページ 1334-46
公開日 2012-6-1
DOI 10.1016/j.biochi.2012.03.001
PII S0300-9084(12)00093-4
PMID 22426385
MeSH Amino Acid Sequence Antiporters / chemistry* Antiporters / genetics Antiporters / metabolism Drug Resistance, Multiple Escherichia coli / chemistry Escherichia coli Proteins / chemistry* Escherichia coli Proteins / genetics Escherichia coli Proteins / metabolism Membrane Transport Proteins / chemistry* Membrane Transport Proteins / metabolism Mutagenesis, Site-Directed
IF 3.413
引用数 18
WOS 分野 BIOCHEMISTRY & MOLECULAR BIOLOGY
リソース情報
原核生物(大腸菌) ME9062(BW25113) mdtM ? mdfA?