Skip to content
Licensed Unlicensed Requires Authentication Published by De Gruyter May 20, 2009

Structural and functional aspects of the multidrug efflux pump AcrB

Thomas Eicher, Lorenz Brandstätter and Klaas M. Pos
From the journal


The tripartite efflux system AcrA/AcrB/TolC is the main pump in Escherichia coli for the efflux of multiple antibiotics, dyes, bile salts and detergents. The inner membrane component AcrB is central to substrate recognition and energy transduction and acts as a proton/drug antiporter. Recent structural studies show that homotrimeric AcrB can adopt different monomer conformations representing consecutive states in an allosteric functional rotation transport cycle. The conformational changes create an alternate access drug transport tunnel including a hydrophobic substrate binding pocket in one of the cycle intermediates.

Corresponding author

Received: 2009-3-1
Accepted: 2009-4-29
Published Online: 2009-05-20
Published in Print: 2009-08-01

©2009 by Walter de Gruyter Berlin New York