A Novel 5-Enolpyruvylshikimate-3-Phosphate Synthase Shows High Glyphosate Tolerance in Escherichia coli and Tobacco Plants

作者：Cao, Gaoyi^*; Liu, Yunjun; Zhang, Shengxue; Yang, Xuewen; Chen, Rongrong; Zhang, Yuwen; Lu, Wei; Liu, Yan; Wang, Jianhua; Lin, Min; Wang, Guoying

来源：PLos One, 2012, 7(6): e38718.

DOI：10.1371/journal.pone.0038718

• HERBICIDE GLYPHOSATE
• 3-PHOSPHATE SYNTHASE
• 5-ENOPYRUVYLSHIKIMATE-3-PHOSPHATE SYNTHASE
• CONFERS RESISTANCE
• DIRECTED EVOLUTION
• STRUCTURAL BASIS
• MOLECULAR-BASIS
• AROA GENE
• IDENTIFICATION
• EXPRESSION

A key enzyme in the shikimate pathway, 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) is the primary target of the broad-spectrum herbicide glyphosate. Identification of new aroA genes coding for EPSPS with a high level of glyphosate tolerance is essential for the development of glyphosate-tolerant crops. In the present study, the glyphosate tolerance of five bacterial aroA genes was evaluated in the E. coli aroA-defective strain ER2799 and in transgenic tobacco plants. All five aroA genes could complement the aroA-defective strain ER2799, and AM79 aroA showed the highest glyphosate tolerance. Although glyphosate treatment inhibited the growth of both WT and transgenic tobacco plants, transgenic plants expressing AM79 aroA tolerated higher concentration of glyphosate and had a higher fresh weight and survival rate than plants expressing other aroA genes. When treated with high concentration of glyphosate, lower shikimate content was detected in the leaves of transgenic plants expressing AM79 aroA than transgenic plants expressing other aroA genes. These results suggest that AM79 aroA could be a good candidate for the development of transgenic glyphosate-tolerant crops.

• 出版日期2012-6-8
• 单位中国农业大学; 中国农业科学院