CRYSTALLIZATION AND PRELIMINARY-X-RAY DIFFRACTION STUDIES OF HUMAN PROCATHEPSIN-L

Human procathepsin L has been expressed in the yeast Pichia pastoris a nd its inactive (Cys25Ser) and unglycosylated (Thr110Ala) mutant purif ied, concentrated to 4 mg/ml, and crystallized by vapor diffusion agai nst solution containing 1.4 M (Na,K)PO4 buffer, pH 7.8. Crystal size w as increased by multiple macroseeding. The crystals are orthorhombic, of space group P2(1)2(1)2(1), with cell dimensions of a = 40.2 Angstro m, b = 88.4 Angstrom, and c = 94.9 Angstrom. A 2.2 Angstrom native dat a set was collected using synchrotron radiation. Although molecular re placement solution for the mature portion of the enzyme was easily fou nd, the resulting maps could not be interpreted in the proregion. Heav y-atom derivative search is in progress. (C) 1996 Wiley-Liss, Inc.