Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, Shandong Province, 27# Shanda South Road, Jinan 250100, People's Republic of China.
J Biochem Mol Toxicol. 2012 Sep;26(9):360-7. doi: 10.1002/jbt.21430. Epub 2012 Jul 16.
Acid yellow 23 (AY23) is a pervasive azo dye used in many fields which is potentially harmful to the environment and human health. This paper studied the toxic effects of AY23 on trypsin by spectroscopic and molecular docking methods. The addition of AY23 effectively quenched the intrinsic fluorescence of trypsin via static quenching with association constants of K(290 K) = 3.67 × 10(5) L mol(-1) and K(310 K) = 1.83 × 10(5) L mol(-1). The calculated thermodynamic parameters conformed that AY23 binds to trypsin predominantly via electrostatic forces with one binding site. Conformational investigations indicated the skeletal structure of trypsin unfolded and the microenvironment of tryptophan changed with the addition of AY23. Molecular docking study showed that AY23 interacted with the His 57 and Lys 224 residue of trypsin and led to the inhibition of enzyme activity. This study offers a more comprehensive picture of AY23-trypsin interaction and indicates their interaction may perform toxic effects within the organism.
酸性黄 23（AY23）是一种普遍使用的偶氮染料，广泛应用于许多领域，但其对环境和人类健康具有潜在危害。本研究采用光谱学和分子对接方法，探究了 AY23 对胰蛋白酶的毒性作用。结果表明，AY23 通过静态猝灭有效地猝灭了胰蛋白酶的内源荧光，其在 290 K 和 310 K 时的结合常数分别为 3.67×10^5 L/mol 和 1.83×10^5 L/mol。计算得到的热力学参数表明，AY23 与胰蛋白酶主要通过静电力结合，且只有一个结合位点。构象研究表明，AY23 的加入导致胰蛋白酶的骨架结构展开，色氨酸的微环境发生变化。分子对接研究表明，AY23 与胰蛋白酶的 His57 和 Lys224 残基相互作用，导致酶活性受到抑制。本研究更全面地揭示了 AY23 与胰蛋白酶的相互作用，并表明它们的相互作用可能在体内产生毒性作用。
