Yu Zhi-Long, Zeng Wei-Cai, Zhang Wen-Hua, Liao Xue-Pin, Shi Bi
The Key Laboratory of Leather Chemistry and Engineering of Ministry of Education, Sichuan University, Chengdu 610065, PR China; National Engineering Laboratory of Clean Technology for Leather Manufacture, Sichuan University, Chengdu 610065, PR China.
The Key Laboratory of Leather Chemistry and Engineering of Ministry of Education, Sichuan University, Chengdu 610065, PR China.
Ultrason Sonochem. 2014 May;21(3):930-6. doi: 10.1016/j.ultsonch.2013.11.002. Epub 2013 Nov 14.
The effect of ultrasound on the activity of α-amylase, papain and pepsin was investigated and the mechanism of the effect was explored by determining their conformational changes. With the irradiation of power ultrasound, the activity of α-amylase and papain was inhibited, while the activity of pepsin was activated. According to the analysis of circular dichroism, Fourier transform infrared and fluorescence spectroscopy, the πo → π(∗) amide transitions and secondary structural components, especially β-sheet, of these three enzymes were significantly influenced by ultrasound. The tryptophan fluorescence intensity of the three enzymes was also observed to be affected by sonication. Furthermore, it was found that the pepsin molecule might gradually be resistant to prolonged ultrasonic treatment and recover from the ultrasound-induced damage to its original structure. The results suggested that the activity of α-amylase, papain and pepsin could be modified by ultrasonic treatment mainly due to the variation of their secondary and tertiary structures.
研究了超声对α-淀粉酶、木瓜蛋白酶和胃蛋白酶活性的影响，并通过测定它们的构象变化来探索其作用机制。在功率超声辐照下，α-淀粉酶和木瓜蛋白酶的活性受到抑制，而胃蛋白酶的活性被激活。根据圆二色性、傅里叶变换红外光谱和荧光光谱分析，这三种酶的πo→π(∗)酰胺跃迁和二级结构成分，尤其是β-折叠，受到超声的显著影响。还观察到超声处理会影响这三种酶的色氨酸荧光强度。此外，发现胃蛋白酶分子可能会逐渐对长时间的超声处理产生抗性，并从超声诱导的损伤中恢复到其原始结构。结果表明，超声处理可改变α-淀粉酶、木瓜蛋白酶和胃蛋白酶的活性，主要是由于它们二级和三级结构的变化。
