Aceto A, Dragani B, Allocati N, Angelucci S, Bucciarelli T, Sacchetta P, Di Ilio C, Martini F
Institute of Biochemical Sciences, University G. D'Annunzio of Chieti, Italy.
Int J Biochem Cell Biol. 1995 Oct;27(10):1033-41. doi: 10.1016/1357-2725(95)00081-y.
Limited proteolysis method has been used to study the structure-function relationship of bacterial glutathione transferase (GSTB1-1). In absence of three-dimensional structural data of prokaryote GST, the results represent the first information concerning the G-site and domains organization of GSTB1-1. The tryptic cleavages occur mainly at the peptide bonds Lys35-Lys36 and Phe43-Leu44, generating two major molecular species of 20-kDa, 3-kDa and traces of 10-kDa. 1-chloro-2,4-dinitrobenzene favoured the proteolysis of the 20-kDa fragment markedly enhancing the production of the 10-kDa peptide by cleaving the chemical bonds Lys87-Ala88 and Arg91-Tyr92. The tryptic cleavage sites of GSTB1-1 was found to be located close to those previously found for the mammalian GSTP1-1 isozyme. It was concluded that despite their low sequence homology (18%), GSTB1-1 and GSTP1-1 displayed similar structural features in their G-site regions and probably a common organization in structural domains.
有限蛋白酶解方法已被用于研究细菌谷胱甘肽转移酶（GSTB1-1）的结构-功能关系。在缺乏原核生物谷胱甘肽转移酶三维结构数据的情况下，这些结果代表了有关GSTB1-1的G位点和结构域组织的首个信息。胰蛋白酶切割主要发生在肽键Lys35-Lys36和Phe43-Leu44处，产生两种主要的分子形式，分别为20 kDa、3 kDa以及痕量的10 kDa。1-氯-2,4-二硝基苯有利于20 kDa片段的蛋白酶解，通过切割化学键Lys87-Ala88和Arg91-Tyr92显著提高10 kDa肽段的产量。发现GSTB1-1的胰蛋白酶切割位点与先前在哺乳动物GSTP1-1同工酶中发现的位点相近。得出的结论是，尽管GSTB1-1和GSTP1-1的序列同源性较低（18%），但它们在G位点区域显示出相似的结构特征，并且在结构域中可能具有共同的组织方式。
