IBR (Instituto de Biología Molecular y Celular de Rosario), Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, S2002LRK, Rosario, Argentina.
J Inorg Biochem. 2010 Jul;104(7):726-31. doi: 10.1016/j.jinorgbio.2010.03.005. Epub 2010 Mar 20.
Glyoxalase II (GLX2, EC 3.1.2.6., hydroxyacylglutathione hydrolase) is a metalloenzyme involved in crucial detoxification pathways. Different studies have failed in identifying the native metal ion of this enzyme, which is expressed with iron, zinc and/or manganese. Here we report that GloB, the GLX2 from Salmonella typhimurium, is differentially inhibited by glutathione (a reaction product) depending on the bound metal ion, and we provide a structural model for this inhibition mode. This metal-dependent inhibition was shown to occur in metal-enriched forms of the enzyme, complementing the spectroscopic data. Based on the high levels of free glutathione in the cell, we suggest that the expression of the different metal forms of GLX2 during Salmonella infection could be exploited as a mechanism to regulate the enzyme activity.
醛糖二酸酶 II(GLX2,EC 3.1.2.6.,羟酰基谷胱甘肽水解酶)是一种参与关键解毒途径的金属酶。不同的研究未能确定该酶的天然金属离子,该酶表达为铁、锌和/或锰。在这里,我们报告称,来自伤寒沙门氏菌的 GLX2 的 GloB 会根据结合的金属离子而被谷胱甘肽(反应产物)不同程度地抑制,并且我们提供了这种抑制模式的结构模型。这种金属依赖性抑制发生在酶的金属富集形式中,补充了光谱数据。基于细胞中高水平的游离谷胱甘肽,我们建议在沙门氏菌感染期间表达 GLX2 的不同金属形式可以作为一种调节酶活性的机制。