Abstract An affinity chromatographic approach was used to investigate the plasmin activity observed in bovine acid whey. Plasminogen-removal gel with tranexamic acid as a ligand was used for selective binding of plasminogen and plasmin through their kringle domains. Subsequently, e-aminocaproic acid was used for elution. Plasmin activity was separated into a bound and non-bound fraction. Surprisingly, only 25% of the total activity in the acid whey was bound to the column, while 50% of the total activity was in the non-bound fraction, and a further 25% of the total activity was unaccounted for. Proteins in the bound fraction were analysed using SDS-PAGE and MALDI-MS/MS fingerprinting analysis, with plasminogen identified. Plasmin activity was purified by a factor of 4313 from the acid whey. The non-bound fraction was subjected to cation-exchange chromatography and zymogram gel analysis and showed the presence of plasminogen-derived proteolytic products such as midi-plasmin, mini-plasmin, and micro-plasmin.

中文翻译：

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了解酸性乳清中纤溶酶-纤溶酶原系统的色谱方法

摘要 亲和色谱方法用于研究在牛酸乳清中观察到的纤溶酶活性。以氨甲环酸作为配体的纤溶酶原去除凝胶用于通过其三环结构域选择性结合纤溶酶原和纤溶酶。随后，使用ε-氨基己酸进行洗脱。纤溶酶活性分为结合部分和非结合部分。令人惊讶的是，酸乳清中只有 25% 的总活性与柱结合，而总活性的 50% 处于非结合部分，另外还有 25% 的总活性下落不明。结合部分中的蛋白质使用 SDS-PAGE 和 MALDI-MS/MS 指纹分析进行分析，并鉴定出纤溶酶原。纤溶酶活性以 4313 的因子从酸乳清中纯化。