Crystallization and preliminary X-ray diffraction studies of a new crystal form of human secretory type IIA phospholipase A₂

Human synovial type IIA phospholipase A₂ (sPLA₂-IIA) has been implicated in the pathogenesis of a number of inflammatory diseases and is a target for the development of therapeutically useful inhibitors. Biochemical evidence suggests a novel mechanism of inhibition for a series of peptide inhibitors originally derived from the primary sequence of the protein. On co-incubation with one of these inhibitors, single crystals of a hitherto unreported crystallographic form of sPLA2-IIA suitable for diffraction analysis were obtained. The crystals belong to the monoclinic space group C2, with unit-cell parameters a = 140.8, b = 38.9, c = 109.1 Å, β = 125.1°, and diffraction at 2.4 Å resolution has been observed.