Crystallization and preliminary X-ray diffraction analysis of a novel trypsin inhibitor from seeds of Copaifera langsdorffii.

A novel trypsin inhibitor isolated from seeds of Copaifera langsdorffii was purified to homogeneity and crystallized. Crystals suitable for X-­ray analysis were grown using the hanging-drop vapour-diffusion method at 291 K in sodium acetate buffer at pH values near 4.3 using PEG 4000 as precipitant. The crystals presented symmetry compatible with the space group P41212 or P43212, with unit-cell parameters a = b = 58.71, c = 93.75 A, and diffracted to 1.83 A resolution at the synchrotron source.