RRC ID 35525
著者 Bay DC, Turner RJ.
タイトル Small multidrug resistance protein EmrE reduces host pH and osmotic tolerance to metabolic quaternary cation osmoprotectants.
ジャーナル J Bacteriol
Abstract The small multidrug resistance (SMR) transporter protein EmrE in Escherichia coli is known to confer resistance to toxic antiseptics classified as quaternary cation compounds (QCCs). Naturally derived QCCs synthesized during metabolic activities often act as osmoprotectants, such as betaine and choline, and participate in osmotic homoestasis. The goal of this study was to determine if EmrE proteins transport biological QCC-based osmoprotectants. Plasmid-encoded copies of E. coli emrE and the inactive variant emrE-E14C (emrE with the E → C change at position 14) were expressed in various E. coli strains grown in either rich or minimal media at various pHs (5 to 9) and under hypersaline (0.5 to 1.0 M NaCl and KCl) conditions to identify changes in growth phenotypes induced by osmoprotectant transport. The results demonstrated that emrE expression reduced pH tolerance of E. coli strains at or above neutral pH and when grown in hypersaline media at or above NaCl or KCl concentrations of 0.75 M. Hypersaline growth conditions were used to screen QCC osmoprotectants betaine, choline, l-carnitine, l-lysine, l-proline, and l-arginine. The study identified that betaine and choline are natural QCC substrates of EmrE.
巻・号 194(21)
ページ 5941-8
公開日 2012-11-1
DOI 10.1128/JB.00666-12
PII JB.00666-12
PMID 22942246
PMC PMC3486072
MeSH Acids / metabolism* Antiporters / genetics Antiporters / metabolism* Cations / metabolism* Escherichia coli / drug effects Escherichia coli / genetics Escherichia coli / growth & development Escherichia coli / physiology* Escherichia coli Proteins / genetics Escherichia coli Proteins / metabolism* Gene Expression Hydrogen-Ion Concentration Osmotic Pressure* Plasmids Potassium Quaternary Ammonium Compounds / metabolism* Salinity Sodium Stress, Physiological*
IF 3.006
引用数 22
WOS 分野 MICROBIOLOGY
リソース情報
原核生物(大腸菌) ME9062(BW25113) JW0531-KC JW5738-KC JW0303-KC JW0304-KC