王冰+杜锦+向春阳+王松文+曹高燚

摘    要：5-磷酸烯醇式丙酮酰-莽草酸-3-磷酸合成酶（EPSPS）是除草剂草甘膦的靶标酶，转基因抗草甘磷作物主要通过转入外源EPSPS编码基因或者对外源EPSPS定点突变来获得。为了扩充草甘膦抗性基因资源，筛选新型草甘膦抗性基因，本研究分离筛选并获得了一株新型草甘膦抗性菌株，16srDNA鉴定显示该菌株属于假单胞菌，该菌株被命名为假单胞菌818。该菌株的获得为进一步筛选克隆草甘膦抗性相关基因提供了可靠保障，丰富了草甘膦抗性基因资源库，获得自主知识产权的新型草甘膦抗性基因有利于应对国外生物技术公司对该领域的垄断，有利于我国遗传改良作物的培育。

关键词：5-磷酸烯醇式丙酮酰-莽草酸-3-磷酸合成酶;草甘膦;假单胞菌;抗草甘膦作物

中图分类号：S482.4         文献标识码：A         DOI 编码：10.3969/j.issn.1006-6500.2016.01.007

Screening and Identification of Glyphosate-Resistant Strain Pseudomonas818

WANG Bing，DU Jin， XIANG Chunyang， WANG Songwen， CAO Gaoyi

（College of Agronomy and Resources and Environment， Tianjin Agricultural University， Tianjin 300384， China）

Abstract： 5-phosphoenolpyruvate shikimic acid acyl-3-phosphate synthase （EPSPS） is the target enzyme of glyphosate. Over expressed exogenous EPSPS gene or site-directed mutagenesis of endogenous EPSPS are the major strategies to gain glyphosate resistant crops. In order to expand the glyphosate resistance gene resources， the glyphosate polluted soil was screened for identifying new glyphosate tolerant microbes. A novel glyphsoate resistant strain was separated which was named as Pseudomonas818 after the amplification of 16 s ribosome DNA. The strain will provide some useful information for cloning glyphosate resistant gene. The research could supplement the bank of glyphosate resistant genes and get rid of the restriction of foreign biotechnology companies. All in all， the novel discovery could provide some useful signals for crop genetic improvement.

Key words： 5-phosphoenolpyruvate shikimic acid acyl-3-phosphate synthase （EPSPS）;glyphosate;Pseudomonas;glyphosate-resistant crops

草甘膦（Glyphosate）作为一种重要的除草剂，具有高效、低毒、在环境中降解快、广谱灭生等优良特性，且制备工艺简单。草甘膦因其种种突出的特性，使其在几十年间得以迅速发展，并成为当今农业生产中生产量及销量最大、使用面积最广的一种除草剂。草甘膦的作用机理主要是竞争性地抑制莽草酸途径中的催化磷酸烯醇式丙酮酸（PEP）和三磷酸莽草酸（S3P）生成5-磷酸烯醇式丙酮酰-莽草酸-3-磷酸（EPSP）的5-磷酸烯醇式丙酮酰-莽草酸-3-磷酸合酶（EPSPS），通过占据EPSPS与底物结合的活性位点导致莽草酸途径的受阻，进而使植物体内莽草酸大量积累，最终使植物产生草甘膦毒害[1]。……