Crystallization and preliminary X‐ray analysis of the catalase–peroxidase KatG from Burkholderia pseudomallei

The bifunctional catalase–peroxidase KatG encoded by the katG gene of Burkholderia pseudomallei has a predicted subunit size of 81.6 kDa. It shows high sequence similarity to other catalase–peroxidases of bacterial, archaebacterial and fungal origin, including 64% identity to KatG from Mycobacterium tuberculosis and lesser sequence similarity to members of the plant peroxidase family. Crystals from this protein were grown in 16–20% PEG 4000, 20% 2‐methyl‐2,4‐pentanediol and 0.1  M sodium citrate pH 5.6 by the hanging‐drop vapour‐diffusion method at 293 K. These crystals diffracted beyond 1.8 Å resolution and belong to space group P 2 1 2 1 2 1 , with unit‐cell parameters a = 100.9, b = 115.6, c = 175.2 Å. The data are consistent with either a monomer or a dimer in the crystal asymmetric unit.