物理化学学报 >> 2010, Vol. 26 >> Issue (01): 215-220.doi: 10.3866/PKU.WHXB20100115

生物物理化学 上一篇    下一篇

含三氟甲基1,2,3-三氮唑衍生物对蘑菇酪氨酸酶活性的抑制动力学

李树白, 聂华丽, 张海涛, 薛勇, CHRIS Branford White, 朱利民   

  1. 东华大学化学化工与生物工程学院, 上海 201620; Institute for Health Research and Policy, London Metropolitan University, London N7 8DB, UK
  • 收稿日期:2009-06-18 修回日期:2009-10-28 发布日期:2009-12-29
  • 通讯作者: 朱利民 E-mail:lzhu@dhu.edu.cn

Inhibitory Kinetics of a Trifluoromethyl-Containing 1,2,3-Triazole Derivative on Mushroom Tyrosinase Activity

LI Shu-Bai, NIE Hua-Li, ZHANG Hai-Tao, XUE Yong, CHRIS Branford White, ZHU Li-Min   

  1. College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620, P. R. China; Institute for Health Research and Policy, London Metropolitan University, London N7 8DB, UK
  • Received:2009-06-18 Revised:2009-10-28 Published:2009-12-29
  • Contact: ZHU Li-Min E-mail:lzhu@dhu.edu.cn

摘要:

研究表明, 含三氟甲基1,2,3-三氮唑衍生物(TF-TZ)对蘑菇酪氨酸酶具有很强的抑制性: 不仅抑制单酚酶活性, 而且对二酚酶活性也是可逆性抑制, 其半抑制浓度IC50分别为30.4和34.5 μmol·L-1, 并且单酚酶延滞时间随着TF-TZ浓度增加而延长. TF-TZ对二酚酶的抑制为抛物线型竞争性抑制, 表明一分子的酶可以和两分子的TF-TZ相结合, 从而形成两种酶-抑制剂复合物: EI和EI2, 其抑制常数分别为76.9和9.71 μmol·L-1. 紫外-可见光谱表明, TF-TZ 和酶相互作用后产成特征的“肩峰”, 说明TF-TZ能够作用于酶的活性中心.

关键词: 含三氟甲基1,2,3-三氮唑, 蘑菇酪氨酸酶, 单酚酶, 二酚酶, 可逆抛物线型竞争性抑制, 铜螯合

Abstract:

 In this study, we demonstrate that the trifluoromethyl-containing 1,2,3-triazole derivative (TF-TZ) inhibits mushroom tyrosinase. TF-TZ could inhibit the monophenolase and diphenolase activities and the inhibition is reversible. IC50 values of 30.4 and 34.5 μmol·L-1 were estimated for the monophenolase activity and the diphenolase activity, respectively. TF-TZ could extend the lag period of the monophenolase activity. Kinetic analysis showed that parabolic-competitive inhibition of TF-TZ occurred on diphenolase. We proposed that two TF-TZ molecules combined with free tyrosinase to formenzyme-inhibitor complexes (EI and EI2), and the inhibition constants (Ki1 for EI and Ki2 for EI2) were 76.9 and 9.71 μmol·L-1, respectively. Moreover, the UV-Visible spectrum of a mixture of tyrosinase and TF-TZ exhibited a characteristic shoulder peak that could be assigned to chelation of TF-TZ to the active site.

Key words: Trifluoromethyl-containing 1,2,3-triazole, Mushroomtyrosinase, Monophenolase, Diphenolase, Reversible parabolic-competitive inhibition, Copper chelation

MSC2000: 

  • O643