Purification and Bicelle Crystallization for Structure Determination of the E. coli Outer Membrane Protein TamA

  • Fabian Gruss
  • Sebastian Hiller
  • Timm Maier
Part of the Methods in Molecular Biology book series (MIMB, volume 1329)


TamA is an Omp85 protein involved in autotransporter assembly in the outer membrane of Escherichia coli. It comprises a C-terminal 16-stranded transmembrane β-barrel as well as three periplasmic POTRA domains, and is a challenging target for structure determination. Here, we present a method for crystal structure determination of TamA, including recombinant expression in E. coli, detergent extraction, chromatographic purification, and bicelle crystallization in combination with seeding. As a result, crystals in space group P21212 are obtained, which diffract to 2.3 Å resolution. This protocol also serves as a template for structure determination of other outer membrane proteins, in particular of the Omp85 family.

Key words

Outer membrane protein Membrane protein purification Bicelle crystallization X-ray crystallography β-Barrel TamA Autotransporter Omp85 Bacterial outer membrane 


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  1. 1.BiozentrumUniversity of BaselBaselSwitzerland

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