Vestling M M, Murphy C M, Fenselau C
Department of Chemistry and Biochemistry, University of Maryland, Baltimore County 21228.
Anal Chem. 1990 Nov 1;62(21):2391-4. doi: 10.1021/ac00220a025.
Potential artifactual contributions are assessed in high-pressure liquid chromatograms and fast atom bombardment mass spectra from autolysis of different preparations of the widely used protease trypsin. Both commercially supplied and laboratory-purified samples were examined. Bovine pancreatic trypsin (1 mg/mL) was found to be completely destroyed in 2 h at pH 8.5, degraded to a complex mixture of small peptides which were characterized by their molecular weights. Some identifications were supported by sequencing by tandem mass spectrometry or by mass spectrometric analysis of the mixture resulting from a single Edman degradation. Autolysis of porcine pancreatic trypsin produced a completely different set of peptides. Five sites of hydrolysis at asparagine residues in bovine trypsin were also identified.
在来自广泛使用的蛋白酶胰蛋白酶不同制剂自溶的高压液相色谱图和快原子轰击质谱中评估潜在的人为因素贡献。对市售和实验室纯化的样品均进行了检测。发现牛胰蛋白酶（1mg/mL）在pH 8.5下2小时内完全被破坏，降解为一组小肽的复杂混合物，这些小肽通过其分子量进行表征。串联质谱测序或单次埃德曼降解产生的混合物的质谱分析支持了一些鉴定结果。猪胰蛋白酶的自溶产生了一组完全不同的肽。还鉴定了牛胰蛋白酶中天冬酰胺残基的五个水解位点。
