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Crystallization and X-ray diffraction analysis of human CLEC-2.

Aleksandra A Watson·Christopher A O'Callaghan
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Abstract

The human C-type lectin-like protein CLEC-2 has recently been shown to be expressed on the surface of platelets and to function as a receptor for the snake-venom protein rhodocytin. The C-type lectin-like domain (CTLD) of CLEC-2 was expressed in Escherichia coli, refolded and purified. Crystals of this recombinant CLEC-2 were grown by sitting-drop vapour diffusion using polyethylene glycol (PEG) 6000 as a precipitant. After optimization, crystals were grown which diffracted to 2.0 A using in-house radiation (lambda = 1.5418 A). These crystals belonged to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 35.407, b = 55.143, c = 56.078 A. The presence of one molecule per asymmetric unit is consistent with a crystal volume per unit weight (VM) of 1.82 A3 Da(-1) and a solvent content of 32.6%. These results suggest that crystals producing diffraction of this quality will be suitable for the structural determination of human CLEC-2.

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Blood PlateletsCloning, MolecularCrystallizationCrystallographyCrystallography, X-RayEscherichia coliHumansLectins, C-TypeMembrane GlycoproteinsPlasmidsPolyethylene GlycolsProtein FoldingProtein Structure, TertiaryRecombinant ProteinsSolventsThrombosisViper VenomsX-Ray DiffractionJournal ArticleResearch Support, Non-U.S. Gov't

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Aleksandra A Watson, Christopher A O'Callaghan. 2005-11-24. Crystallization and X-ray diffraction analysis of human CLEC-2.. https://doi.org/10.1107/s1744309105037991

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