Crystallographic analysis of AcrB
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Updated: Aug 24, 2026

Fully Autonomous Characterization and Data Collection from Crystals of Biological Macromolecules
Published on: March 22, 2019
Klaas M Pos1, André Schiefner, Markus A Seeger
1Institut für Mikrobiologie, D-Biol, ETH Zürich, Schmelzbergstr. 7, CH-8092 Zürich, Switzerland. pos@micro.biol.ethz.ch
Abstract:
A His-tagged derivative of the multidrug efflux pump AcrB could be crystallized in three different space groups (R3, R32 and P321). Experimental MAD-phasing maps from R32 AcrB(His) crystals were obtained to a resolution of 3.5 A. Datasets of native and substrate soaked AcrB(His) crystals were collected at the Swiss Light Source X06SA beamline up to a resolution of 2.7 A and refinement of these data provided good quality electron density maps, which allowed us to complement the published AcrB structure (PDB code 1iwg). Introduction of amino acids 860-865 and 868 lacking in the 1iwg structure and deletion of a highly disordered region (amino acids 669-678) improved R(free) and average B factors in the 2.7 A model. We could not identify significant densities indicating specific antibiotic binding sites in the AcrB R32 space group datasets under the soaking conditions tested.
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