Crystallographic Analysis of the CusBA Heavy-Metal Efflux Complex of Escherichia coli

Part of the Methods in Molecular Biology book series (MIMB, volume 1700)


Crystallization is one of the most successful techniques used to determine protein structure, especially for membrane proteins. However, the application of this technique is not straightforward and often hampered by the difficulties associated with expression, purification, and crystallization. Here we present our protocol and methodology for crystallizing the CusBA adaptor–transporter complex of Escherichia coli. Using these procedures, we were able to produce the first co-crystal structure of a resistance-nodulation-cell division (RND) transporter in complex with its associated membrane fusion protein.

Key words

Membrane protein X-ray crystallography Vapor diffusion Heavy-metal efflux Antimicrobial resistance 



This work was supported by an NIH grant R01AI114629 to E.W.Y.


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© Springer Science+Business Media LLC 2018

Authors and Affiliations

  1. 1.Department of Physics and AstronomyIowa State UniversityAmesUSA
  2. 2.Department of ChemistryIowa State UniversityAmesUSA

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