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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 X-ray diffraction studies of new crystal forms of Escherichia coli P(II) complexed
K J Edwards1, P M Suffolk, P D Carr
1Centre for Molecular Structure and Function, Research School of Chemistry, Australian National University, Canberra. karen.edwards@anu.edu.au
Abstract:
New crystals of the signal-transducing protein P(II) have been obtained in the presence of a number of different effector ligands. Various crystal forms are observed depending on the nature of the ligand(s). Co-crystallization with 2-ketoglutarate, glutamate and pyrophosphate produces hexagonal crystals similar to the wild type, ATP yields cubic crystals and ATP in conjunction with 2-ketoglutarate or glutamate yields orthorhombic crystal forms. All of the above crystals have been characterized by X-ray diffraction analysis. The hexagonal crystals belong to space group P6(3), cubic crystals to either I23 or I2(1)3 and orthorhombic crystals to I222. A molecular-replacement solution for the P(II)/ATP/2-ketoglutarate crystals has been obtained giving us an initial model for a trimer in the orthorhombic crystal form.
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