Expression, purification, crystallization and preliminary X-ray diffraction studies of phosphoglycerate kinase from methicillin-resistant Staphylococcus aureus MRSA252

Phosphoglycerate kinase (PGK) from methicillin-resistant Staphylococcus aureus MRSA252 has been cloned in pQE30 expression vector, overexpressed in Escherichia coli SG13009 (pREP4) cells and purified to homogeneity. The protein was crystallized from 0.15 M CaCl₂, 0.1 M HEPES–NaOH pH 6.8, 20%(w/v) polyethylene glycol 2000 at 298 K by the hanging-drop vapour-diffusion method. The crystals belonged to space group P2₁, with unit-cell parameters a = 45.14, b = 74.75, c = 58.67 Å, β = 95.72°. X-ray diffraction data have been collected and processed to a maximum resolution of 2.3 Å. The presence of one molecule in the asymmetric unit gives a Matthews coefficient (V_M) of 2.26 ų Da⁻¹ with a solvent content of 46%. The structure has been solved by molecular replacement and structure refinement is now in progress.