z-logo
open-access-imgOpen Access
Structural Asymmetry of AcrB Trimer Suggests a Peristaltic Pump Mechanism
Author(s) -
Markus A. Seeger,
A. Schiefner,
Thomas Eicher,
François Verrey,
Kay Diederichs,
Klaas M. Pos
Publication year - 2006
Publication title -
science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 12.556
H-Index - 1186
eISSN - 1095-9203
pISSN - 0036-8075
DOI - 10.1126/science.1131542
Subject(s) - trimer , efflux , monomer , chemistry , biophysics , escherichia coli , inner membrane , crystallography , transporter , stereochemistry , bacterial outer membrane , membrane , biochemistry , polymer , biology , dimer , organic chemistry , gene
The AcrA/AcrB/TolC complex spans the inner and outer membranes of Escherichia coli and serves as its major drug-resistance pump. Driven by the proton motive force, it mediates the efflux of bile salts, detergents, organic solvents, and many structurally unrelated antibiotics. Here, we report a crystallographic structure of trimeric AcrB determined at 2.9 and 3.0 angstrom resolution in space groups that allow asymmetry of the monomers. This structure reveals three different monomer conformations representing consecutive states in a transport cycle. The structural data imply an alternating access mechanism and a novel peristaltic mode of drug transport by this type of transporter.

The content you want is available to Zendy users.

Already have an account? Click here to sign in.
Having issues? You can contact us here
Accelerating Research

Address

John Eccles House
Robert Robinson Avenue,
Oxford Science Park, Oxford
OX4 4GP, United Kingdom