A fully functional deletion staphylokinase derivative crystallizes in two non-isomorphous monoclinic modifications

Two non-isomorphous monoclinic types of diffraction-quality crystals of Del ta 10Sak, a fully functional staphylokinase derivative lacking the first te n amino acids, have been grown by the hanging-drop vapour-diffusion techniq ue. Type I crystals grow from a solution containing Zn(OAc)(2), Tris buffer pH 7.5 and PEG 8000, while type II crystals can be obtained from a solutio n containing MgCl2, Tris buffer pH 8.5 and PEG 4000. Both crystal types wer e suitable for data collection (to 2.4 and 2.6 Angstrom resolution, respect ively) and further structural investigation.