title: Characterization of a class II 5-enopyruvylshikimate-3-phosphate synthase with high tolerance to glyphosate from Sinorhizobium fredii.
abstract: 5-Enopyruvylshikimate-3-phosphate synthase (EPSP synthase) is an important enzyme in the shikimate pathway mediating the biosynthesis of aromatic compounds in plants and microorganisms. A novel class II EPSP synthase AroA S. fredii from Sinorhizobium fredii NGR234 was overexpressed in Escherichia coli BL21. It was purified to homogeneity and its catalytic properties were studied. The enzyme exhibited optimum catalytic activity at pH 8.0 and 50 °C. It was stable below 40 °C, and over a broad range of pH 5.0-9.0. The EPSP synthase was increasingly activated by 100 mM of the chlorides of NH4 (+), K(+), Na(+) and Li(+). Kinetic analysis of AroA S. fredii suggested that the enzyme exhibited a high glyphosate tolerance and high level of affinity for phosphoenolpyruvate, which indicates the enzyme with a high potential for structural and functional studies and its potential usage for the generation of transgenic crops resistant to the herbicide.
authors.affiliation: Shanghai Key Laboratory of Agricultural Genetics and Breeding, Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, 2901 Beidi Road, Shanghai, China, wanglijuan_abc@126.com.
authors.forename: Lijuan
authors.initials: L
authors.lastname: Wang
authors.forename: Rihe
authors.initials: R
authors.lastname: Peng
authors.forename: Yongsheng
authors.initials: Y
authors.lastname: Tian
authors.forename: Jing
authors.initials: J
authors.lastname: Han
authors.forename: Wei
authors.initials: W
authors.lastname: Zhao
authors.forename: Bo
authors.initials: B
authors.lastname: Wang
authors.forename: Man
authors.initials: M
authors.lastname: Liu
authors.forename: Quanhong
authors.initials: Q
authors.lastname: Yao
mesh_terms: D051229:3-Phosphoshikimate 1-Carboxyvinyltransferase / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D020536:Enzyme Activators / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000378:metabolism*; D004795:Enzyme Stability; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D005998:Glycine / Q000031:analogs & derivatives* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008670:Metals / Q000378:metabolism; D010728:Phosphoenolpyruvate / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D042181:Sinorhizobium fredii / Q000201:enzymology* / Q000235:genetics; D013696:Temperature; D000097797:Glyphosate
chemical_list: D051229:3-Phosphoshikimate 1-Carboxyvinyltransferase; D020536:Enzyme Activators; D004791:Enzyme Inhibitors; D005998:Glycine; D008670:Metals; D010728:Phosphoenolpyruvate; D011994:Recombinant Proteins; D000097797:Glyphosate