Abstract: Typical UV of CuMT scans from 220 to 350nm and exhibits a shoulder near 260nm. Cleavage of Cu-sulfur bond was detected by the decrease of absorbance of 260nm in UV spectra. Kinetics of the H₂O₂ dependent cleavage of Cu-thiolate centers in copper reconstituted mammalian CuMT was studied. The kinetics type and the possible linear dependency of the rate constants on the H₂O₂ concentration were performed. The cleavage of Cu-thiolate center in CuMT was compared with that of (Cu, Zn)MT. The results first show that zinc can stabilize the Cu-S chromophore in (Cu, Zn)MT directly.

Key words: metallothionein, H₂O₂, the cleavage of Cu-S bond

摘要： CuMT紫外光谱的特点是在200～350nm有吸收，在260nm处有一肩峰。260nm的紫外吸收为CuMT中Cu-S键的特征吸收，因此通过观察紫外光谱中CuMT在260nm处吸光度的变化，研究了H₂O₂引起哺乳动物CuMT中Cu-S键断裂的反应动力学，并且比较了MT中金属组成对反应动力学的影响，结果表明，锌的存在可以稳定CuMT。

关键词: 金属硫蛋白, H₂O₂, Cu-S键断裂