Purification, crystallization and preliminary X-ray analysis of IMP-18, a class B carbapenemase from Pseudomonas aeruginosa

Class B β‐lactamases are known as metallo‐β‐lactamases (MBLs) and they hydrolyze most β‐lactams, including carbapenems. IMP‐18, an MBL cloned from Pseudomonas aeruginosa, was overexpressed, purified and crystallized by vapour diffusion for X‐ray crystallographic analysis. Preliminary X‐ray analysis showed that the crystal diffracted to 2.4 Å resolution and belonged to the tetragonal space group P41212, with unit‐cell parameters a = b = 120.77, c = 96.54 Å, α = β = γ = 90°, suggesting the presence of two molecules in the asymmetric unit.