Crystallization and preliminary X-ray diffraction analysis of shikimate kinase from Mycobacterium tuberculosis in complex with MgADP

Shikimate kinase (SK) from Mycobacterium tuberculosis (Mt) was overexpresse d in Escherichia coli, purified and cocrystallized with MgADP in hanging dr ops using the vapor-diffusion procedure with PEG 4000 and 2-propanol as pre cipitants at pH 7.5. The crystal of MtSK-MgADP, which diffracted to 2.2 Ang strom resolution, belonged to space group P3(2)21 or P3(1)21, with unit-cel l parameters a=b=64.01, c=92.41 Angstrom. There was one MtSK molecule in th e asymmetric unit. Molecular-replacement trials with the crystal structure of SK from Erwinia chrysanthemi (PDB code 1shk) and adenylate kinase (PDB c ode 1ake) as search models were not successful. Heavy-atom derivative scree ning is in progress.