The pneumococcal phosphorylcholine esterase (Pce or CbpE) is a modular protein that hydrolyses the phosphorylcholine residues present in the teichoic and lipoteichoic acids of the pneumococcal cell wall. Pce has been crystallized using the hanging-drop vapour-diffusion method at 291 K. Diffraction-quality monoclinic crystals belong to space group C2, with unit-cell parameters a = 169.82, b = 57.26, c = 67.44 Å, β = 112.60°. A 2.7 Å resolution SAD data set from a non-isomorphous Gd-HPDO3A Pce derivative was collected at the gadolinium L III absorption edge using synchrotron radiation.This work was supported by grants from the Spanish Ministry of Science and Technology (BIO2000-1307, BIO2002-02887, BIO2003-01952 and BMC2003-00074). LL holds a fellowship from the Spanish Ministry of Science and Technology.Peer reviewed