鸵鸟（鸵鸟属骆驼鸵鸟）胰腺中胰凝乳蛋白酶原的分离与部分特性鉴定

The isolation and partial characterization of chymotrypsinogen from the pancreas of the ostrich (Struthio camelus).

van der Westhuizen N, Naudé R J, Oelofsen W

Department of Biochemistry, University of Port Elizabeth, Republic of South Africa.

Int J Biochem. 1989;21(1):91-7. doi: 10.1016/0020-711x(89)90031-1.

Abstract

Cationic chymotrypsinogen from the pancreas of the ostrich was purified to homogeneity by sulfuric acid extraction of pancrei, (NH4)2SO4 fractionation and SP-Sephadex C-50 and Sephadex G-100 chromatography. 2. The final preparation was homogeneous when subjected to SDS-PAGE, isoelectric focusing and sedimentation equilibrium centrifugation. The Mmin value obtained from amino acid analysis was 25,572 Da. A mean sedimentation coefficient of 2.575 S was obtained by sedimentation velocity centrifugation. 3. N-terminal analysis by dansylation showed an Ala residue which is the N-terminal of a neochymotrypsinogen. 4. The effects of pH, temperature and inhibitors (LBTI, PMSF, TPCK and DFP) on the chymotryptic activity were examined. A Km-value for ATEE as substrate was found to be 0.57 mM.

摘要

通过硫酸提取鸵鸟胰腺、硫酸铵分级分离以及SP-葡聚糖凝胶C-50和葡聚糖凝胶G-100色谱法，将鸵鸟胰腺中的阳离子胰凝乳蛋白酶原纯化至同质。2. 最终制剂经十二烷基硫酸钠-聚丙烯酰胺凝胶电泳、等电聚焦和沉降平衡离心处理后呈现同质。通过氨基酸分析获得的最小分子量值为25,572道尔顿。通过沉降速度离心获得的平均沉降系数为2.575 S。3. 丹磺酰化法进行的N端分析显示存在一个丙氨酸残基，它是新胰凝乳蛋白酶原的N端。4. 研究了pH、温度和抑制剂（亮抑酶肽、苯甲基磺酰氟、甲苯磺酰-L-苯丙氨酸氯甲基酮和二异丙基氟磷酸）对胰凝乳蛋白酶活性的影响。发现以对甲苯磺酰-L-精氨酸甲酯为底物时的米氏常数为0.57 mM。