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Combining Wet and Dry Lab Techniques to Guide the Crystallization of Large Coiled-coil Containing Proteins
Published on: January 6, 2017
Crystallization and preliminary structure analysis of CobE, an essential protein of cobalamin (vitamin B12)
Jitka Vévodová1, Ross M Graham, Evelyne Raux
1Department of Chemistry, University of York, Heslington, York YO10 5YW, England.
Abstract:
CobE, a protein implicated in vitamin B12 biosynthesis, from Pseudomonas aeruginosa has been overexpressed in Escherichia coli, purified and crystallized using hanging-drop vapour diffusion. The crystals belong to the primitive orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 31.86, b = 41.07, c = 87.41 A. The diffraction extends to a resolution of 1.9 A. There is one molecule per asymmetric unit and the estimated solvent content is 35%. SeMet-labelled CobE has been prepared and crystallizes under the same conditions as the native protein with diffraction to 1.7 A. The anomalous measurements will be used for phasing.
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