一种酶-抑制剂复合物的结晶：蛋白酶K与其蛋白抑制剂PK13

Crystallization of an enzyme-inhibitor complex: proteinase K with its protein inhibitor, PK13.

作者信息

Pal G P, Jany K D, Tsernoglou D

机构信息

European Molecular Biology Laboratory, Heidelberg, Germany.

出版信息

Proteins. 1994 Jun;19(2):161-2. doi: 10.1002/prot.340190210.

DOI:10.1002/prot.340190210

PMID:8090711

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%.

摘要

通过微透析技术制备了蛋白酶K（分子量28,790道尔顿）与其天然存在的蛋白抑制剂PK13（19,641道尔顿）的复合物晶体，并通过在50 mM Tris-HCl（pH 7.8）中对抗25%硫酸铵的悬滴气相扩散进行修饰。晶体为长棱柱体，菱形横截面尺寸为0.2×0.4×1.5 mm3，能将X射线衍射至2.5埃的分辨率。它们属于正交空间群P2(1)2(1)2(1)，晶胞尺寸a = 64.1埃，b = 66.8埃，c = 133.8埃。假设不对称单元中有一个完整的复合物，则可得VM = 2.95埃3/道尔顿，溶剂含量Vsolv = 58.3%。