3FJX

E. coli EPSP synthase (T97I) liganded with S3P

3FJX の概要

• エントリーDOI: 10.2210/pdb3fjx/pdb
• 関連するPDBエントリー: 1g6t 2qft 3FJZ 3FK0 3FK1
• 分子名称: 3-phosphoshikimate 1-carboxyvinyltransferase, SHIKIMATE-3-PHOSPHATE, FORMIC ACID, ... (4 entities in total)
• 機能のキーワード: inside-out alpha-beta barrel, amino-acid biosynthesis, aromatic amino acid biosynthesis, transferase
• 由来する生物種: Escherichia coli K-12
• 細胞内の位置: Cytoplasm (Probable): P0A6D3
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 46776.00

構造登録者

Schonbrunn, E. (登録日: 2008-12-15, 公開日: 2009-02-17, 最終更新日: 2023-09-06)

主引用文献

Funke, T.,Yang, Y.,Han, H.,Healy-Fried, M.,Olesen, S.,Becker, A.,Schonbrunn, E.
Structural Basis of Glyphosate Resistance Resulting from the Double Mutation Thr97 -> Ile and Pro101 -> Ser in 5-Enolpyruvylshikimate-3-phosphate Synthase from Escherichia coli.
J.Biol.Chem., 284:9854-9860, 2009

PubMed Abstract: The shikimate pathway enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) is the target of the broad spectrum herbicide glyphosate. The genetic engineering of EPSPS led to the introduction of glyphosate-resistant crops worldwide. The genetically engineered corn lines NK603 and GA21 carry distinct EPSPS enzymes. CP4 EPSPS, expressed in NK603 corn and transgenic soybean, cotton, and canola, belongs to class II EPSPS, glyphosate-insensitive variants of this enzyme isolated from certain Gram-positive bacteria. GA21 corn, on the other hand, was created by point mutations of class I EPSPS, such as the enzymes from Zea mays or Escherichia coli, which are sensitive to low glyphosate concentrations. The structural basis of the glyphosate resistance resulting from these point mutations has remained obscure. We studied the kinetic and structural effects of the T97I/P101S double mutation, the molecular basis for GA21 corn, using EPSPS from E. coli. The T97I/P101S enzyme is essentially insensitive to glyphosate (K(i) = 2.4 mm) but maintains high affinity for the substrate phosphoenolpyruvate (PEP) (K(m) = 0.1 mm). The crystal structure at 1.7-A resolution revealed that the dual mutation causes a shift of residue Gly(96) toward the glyphosate binding site, impairing efficient binding of glyphosate, while the side chain of Ile(97) points away from the substrate binding site, facilitating PEP utilization. The single site T97I mutation renders the enzyme sensitive to glyphosate and causes a substantial decrease in the affinity for PEP. Thus, only the concomitant mutations of Thr(97) and Pro(101) induce the conformational changes necessary to produce catalytically efficient, glyphosate-resistant class I EPSPS.

PubMed: 19211556
DOI: 10.1074/jbc.M809771200

実験手法

X-RAY DIFFRACTION (1.75 Å)