性酸酶 - 链维丁联合体 (APSA) 酶和随着时间的推移和储存条件的结合活性
Nan Cheng1, Lloyd Johnson1, Jaimie Dufresne1
1Research Analytical Biochemistry Laboratory, Department of Chemistry and Biology, Faculty of Science, Toronto Metropolitan University, 350 Victoria Street, Toronto, Ontario, M5B 2K3, Canada.
Biochemistry and biophysics reports
|July 28, 2025
概括
性酸酶 (AP) 斯特雷普塔维丁 (SA) 结合物 (APSA) 随着时间的推移由于蛋白质分解而失去活性. 添加甘油或糖,并在-20°C或湿冰上储存,显著提高了APSA的稳定性.
科学领域:
- 生物化学 生物化学
- 酶结合技术 酶结合技术
- 诊断检测试验 诊断检测试验
背景情况:
- 性酸酶 (AP) 和链状维丁 (SA) 结合物 (APSA) 对于世界各地的各种诊断查至关重要.
- 在液态阶段的APSA结合物的酶活性表现出变化,并随着储存时间的推移而下降.
- 牛血清白蛋白 (BSA) 载体的蛋白质分解,而不是AP与SA的解离,有助于活性丧失.
研究的目的:
- 为了研究APSA结合物的稳定性和活动丧失随着时间的推移.
- 确定影响APSA稳定性的因素,包括储存条件和保护性添加剂.
- 为诊断应用开发保护APSA酶活性的策略.
主要方法:
- 在各种条件下储存的APSA合物上进行了酶活性测试.
- 蛋白酶抑制剂被用来探测活动丧失的机制.
- 在评估温度,甘油,冷干燥和冷保护剂 (三糖,糖糖) 对储存时间内的活性的影响之前,APSA合物进行了定位和标准化.
主要成果:
- APSA酶活性显示出显著的变化,并随着储存时间的推移而下降,观察到BSA载体的蛋白解.
- 协同蛋白酶抑制剂废除了AP活性,而竞争性抑制剂没有保护作用.
- 在湿冰上或在-20°C的50%糖中储存,在170天后保留了大约50%的初始APSA活性,这表明稳定性有所改善.
结论:
- APSA结合物的稳定性受到储存时间和温度的显著影响,蛋白质分解是活动丧失的关键因素.
- 添加甘油和糖 (三糖,糖) 等冷保护剂可以减轻APSA活动损失.
- 优化的储存条件,如湿冰或-20°C的糖醇,可以提高APSA结合物的保质期用于诊断用途.
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