title: Crystallization of an enzyme-inhibitor complex: proteinase K with its protein inhibitor, PK13.
abstract: Crystals of a complex of proteinase K (molecular mass, 28,790 Da) with its naturally occurring protein inhibitor PK13 (19,641 Da), have been prepared by a microdialysis technique and modified by hanging drop vapor diffusion against 25% ammonium sulfate in 50 mM Tris-HCl, pH 7.8. The crystals are long prisms with diamond-shaped cross sections of 0.2 x 0.4 x 1.5 mm3 and they diffract X-rays to a resolution of 2.5 A. They belong to the orthorhombic space group P2(1)2(1)2(1) with cell dimensions a = 64.1 A, b = 66.8 A, and c = 133.8 A. Assuming one whole complex in the asymmetric unit, one obtains VM = 2.95 A3/Da and the solvent content, Vsolv = 58.3%.
authors.affiliation: European Molecular Biology Laboratory, Heidelberg, Germany.
authors.forename: G P
authors.initials: GP
authors.lastname: Pal
authors.forename: K D
authors.initials: KD
authors.lastname: Jany
authors.forename: D
authors.initials: D
authors.lastname: Tsernoglou
mesh_terms: D002850:Chromatography, Gel; D003460:Crystallization; D018360:Crystallography, X-Ray; D004591:Electrophoresis, Polyacrylamide Gel; D019286:Endopeptidase K; D005658:Fungi / Q000201:enzymology; D011480:Protease Inhibitors / Q000737:chemistry*; D012697:Serine Endopeptidases / Q000737:chemistry*
chemical_list: D011480:Protease Inhibitors; D012697:Serine Endopeptidases; D019286:Endopeptidase K