Structural highlights
Function
[ACRB_ECOLI] AcrAB is a drug efflux protein with a broad substrate specificity.[1] [2] [3]
Publication Abstract from PubMed
The formation of well-diffracting crystals is a major bottleneck in structural analysis of membrane proteins by X-ray crystallography. One approach to improve crystal quality is the use of DARPins as crystallization chaperones. Here, we present a detailed analysis of the interaction between DARPins and the integral membrane protein AcrB. We find that binders selected in vitro by ribosome display share a common epitope. The comparative analysis of three crystal structures of AcrB-DARPin complexes allowed us to study the plasticity of the interaction with this dominant binding site. Seemingly redundant AcrB-DARPin crystals show substantially different diffraction quality as a result of subtle differences in the binding geometry. This work exemplifies the importance to screen a number of crystallization chaperones to obtain optimal diffraction data. Crystallographic analysis is complemented by biophysical characterization of nine AcrB binders. We observe that small variations in the interface can lead to differing behavior of the DARPins with regards to affinity, stoichiometry of the complexes and specificity for their target.
Designed ankyrin repeat protein binders for the crystallization of AcrB: Plasticity of the dominant interface.,Monroe N, Sennhauser G, Seeger MA, Briand C, Grutter MG J Struct Biol. 2011 May;174(2):269-81. Epub 2011 Feb 4. PMID:21296164[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Murakami S, Nakashima R, Yamashita E, Matsumoto T, Yamaguchi A. Crystal structures of a multidrug transporter reveal a functionally rotating mechanism. Nature. 2006 Sep 14;443(7108):173-9. Epub 2006 Aug 16. PMID:16915237 doi:10.1038/nature05076
- ↑ Seeger MA, Schiefner A, Eicher T, Verrey F, Diederichs K, Pos KM. Structural asymmetry of AcrB trimer suggests a peristaltic pump mechanism. Science. 2006 Sep 1;313(5791):1295-8. PMID:16946072 doi:313/5791/1295
- ↑ Sennhauser G, Amstutz P, Briand C, Storchenegger O, Grutter MG. Drug export pathway of multidrug exporter AcrB revealed by DARPin inhibitors. PLoS Biol. 2007 Jan;5(1):e7. PMID:17194213 doi:10.1371/journal.pbio.0050007
- ↑ Monroe N, Sennhauser G, Seeger MA, Briand C, Grutter MG. Designed ankyrin repeat protein binders for the crystallization of AcrB: Plasticity of the dominant interface. J Struct Biol. 2011 May;174(2):269-81. Epub 2011 Feb 4. PMID:21296164 doi:10.1016/j.jsb.2011.01.014
