Structural analysis of a glutathione transferase A1-1 mutant tailored for high catalytic efficiency with toxic alkenals.
Structural analysis of a glutathione transferase A1-1 mutant tailored for high catalytic efficiency with toxic alkenals.
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DOI：
10.1021/bi900895b
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发表时间：
2009-08-18
期刊：
影响因子：
2.9
通讯作者：
Atkins WM
中科院分区：
文献类型：
--
作者：
Balogh LM;Le Trong I;Kripps KA;Tars K;Stenkamp RE;Mannervik B;Atkins WM
The specificity of human glutathione transferase (GST) A1-1 is drastically altered to favor alkenal substrates in the GIMFhelix mutant designed to mimic first-sphere interactions utilized by GSTA4-4. This redesign serves as a model to further understand the structural determinants that contribute to the distinct specificities of alpha class GSTs. Herein we report the first crystal structures of GIMFhelix, both in complex with GSH and in apo form at 1.98 and 2.38 Ǻ resolution. In contrast to the pre-organized hydrophobic binding pocket that accommodates alkenals in GSTA4-4, GSTA1-1 includes a dynamic α9-helix that undergoes a ligand-dependent localization to complete the active site. Comparisons of the GIMFhelix structures with previously reported structures show a striking similarity with the GSTA4-4 active site obtained within an essentially GSTA1-1 scaffold and reveal the α9-helix assumes a similar localized structure regardless of active site occupancy in a manner resembling GSTA4-4. However, all the structural elements important in GSTA4-4 are not entirely accounted for within the mutant's active site. The contribution of Phe10 to the Tyr212-Phe10-Phe220 network prevents complete C-terminal closure and demonstrates that the presence of Phe10 within the context of a GSTA4-4-like active site may ultimately hinder Phe220, a key C-terminal residue, from effectively contributing to the active site. In total these results illustrate the remaining structural differences presumably reflected in the previously reported catalytic efficiencies of GIMFhelix and GSTA4-4 and emphasize the F10P mutation as necessary to completely accomplish the transformation to a highly specific GST from the more promiscuous GSTA1-1 enzyme.
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影响因子：
2.9
作者：
Gustafsson, A;Etahadieh, M;Mannervik, B
通讯作者：
Mannervik, B
DOI：
10.1107/s0907444905039296
发表时间：
2006-02-01
影响因子：
2.2
作者：
Grahn, E;Novotny, M;Kleywegt, GJ
通讯作者：
Kleywegt, GJ
影响因子：
4.1
作者：
Hubatsch, I;Ridderström, M;Mannervik, B
通讯作者：
Mannervik, B
影响因子：
14.9
作者：
Davis IW;Leaver-Fay A;Chen VB;Block JN;Kapral GJ;Wang X;Murray LW;Arendall WB 3rd;Snoeyink J;Richardson JS;Richardson DC
通讯作者：
Richardson DC
影响因子：
5.7
作者：
CAMERON, AD;SINNING, I;JONES, TA
通讯作者：
JONES, TA