Open AccessCross-Linked Complex between Oligomeric Periplasmic Lipoprotein AcrA and the Inner-Membrane-Associated Multidrug Efflux Pump AcrB from Escherichia coli
Author(s) -
Helen I. Zgurskaya,
Hiroshi Nikaido
Publication year - 2000
Publication title -
journal of bacteriology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.652
H-Index - 246
eISSN - 1067-8832
pISSN - 0021-9193
DOI - 10.1128/jb.182.15.4264-4267.2000
Subject(s) - periplasmic space , efflux , biology , escherichia coli , inner membrane , multidrug resistance associated proteins , bacterial outer membrane , membrane transport protein , transporter , biochemistry , membrane protein , transport protein , chemiosmosis , multiple drug resistance , permease , microbiology and biotechnology , membrane , atp binding cassette transporter , enzyme , antibiotics , gene , atp synthase
InEscherichia coli , the intrinsic levels of resistance to multiple antimicrobial agents are produced through expression of the three-component multidrug efflux system AcrAB-TolC. AcrB is a proton-motive-force-dependent transporter located in the inner membrane, and AcrA and TolC are accessory proteins located in the periplasm and the outer membrane, respectively. In this study, these three proteins were expressed separately, and the interactions between them were analyzed by chemical cross-linking in intact cells. We show that AcrA protein forms oligomers, most probably trimers. In this oligomeric form, AcrA interacts specifically with AcrB transporter independently of substrate and TolC.