Crystallization and preliminary diffraction studies of prostaglandin E2-specific monoclonal antibody Fab fragment in the ligand complex

摘要

Prostaglandin E2 is a major lipid mediator that regulates diverse biological processes. To elucidate how prostaglandin E2 is recognized specifically by its antibody, the Fab fragment of a monoclonal anti-prostaglandin E2 antibody was prepared and its complex with prostaglandin E2 was crystallized. The stable Fab–prostaglandin E2 complex was prepared by gel-filtration chromatography. Crystals were obtained by the microbatch method at 277 K using polyethylene glycol 4000 as a precipitant. A diffraction data set was collected to 2.2 Å resolution. The crystals belonged to space group P212121, with unit-cell parameters a = 70.3, b = 81.8, c = 82.2 Å. The asymmetric unit was suggested to contain one molecule of the Fab–prostaglandin E2 complex, with a corresponding crystal volume per protein weight of 2.75 ų Da⁻¹.