REU: Ecological Interactions of Genetically-Engineered Microorganisms in Root-Soil Systems

格鲁吉亚大学的彼得·哈特尔博士和他的同事们， 雅典提议对几个关键的， 基因工程的生态学问题 微生物的 微生物生存，生长， 并在不断变化的土壤环境中相互作用， 微生物积极地水平交换基因， 性状 通过询问一系列问题，调查人员将 评估微生物特定基因的生态价值 在根/土壤系统中。 他们利用基因工程 克隆和操作编码内切葡聚糖酶的基因， 青枯假单胞菌中的多聚半乳糖醛酸酶。 他们将使用相同的技术来编码 胞外多糖、蛋白酶和脂肪酶。 的损失 这些特异性基因的表达将单独测试， 组合对青枯病菌的能力的影响， 存活，生长，并转移这些克隆基因在土壤中， 根际对番茄（Lycopersicon esculentum）的影响。 克隆的 基因也将被放置在恶臭假单胞菌，假单胞菌 铜绿假单胞菌和大肠杆菌。 光球的相互作用将 通过使用根际细胞进行评估， 不同的孔隙率。 通过这种方式，微生物 基因工程细菌的竞争力将是 评估。 这项研究预计将产生基本的 一个特定基因的生态价值的知识， 环境中的微生物。 基因的初步研究 对于青枯菌中的内切葡聚糖酶和多聚半乳糖醛酸酶， 表明基因工程对人类 这种生物在植物中的表现。 这些数据将对微生物生态学家有直接价值， 监管机构关注的意外释放 基因工程微生物

Drs. Peter Hartel and colleagues at the University of Georgia, Athens propose to conduct research on several critical, ecological questions concerning genetically engineered microorganisms. The ability of a microorganism to survive, grow, and interact in a ever changing soil environment persists because microorganisms actively exchange genes horizontally for these traits. By asking a series of questions, the investigators will assess the ecological worth of specific genes to a microorganism in a root/soil system. They have used genetic engineering to clone and manipulate the genes which encode for endoglucanase and polygalacturonase in the bacterium Pseudomonas solanacearum. They will use the same techniques for the genes encoding for extracellular polysaccharide, protease, and lipase. The loss of expression of these specific genes will be tested singly and in combination for their effect on the ability of P. solanacearum to survive, grow, and transfer these cloned genes in soil and in the rhizosphere to tomato (Lycopersicon esculentum). The cloned genes will also be placed in Pseudomonas putida, Pseudomonas aeruginosa, and Escherichia coli. Rhizosphere interactions will be assessed by use of a rhizosphere cell employing membranes of varying porosities. In this manner, the microbial competitiveness of the genetically-engineered bacteria will be assessed. The research is expected to yield fundamental knowledge on the ecological value of a specific gene to a microorganism in the environment. Preliminary work on the genes for endoglucanase and polygalacturonase in P. solanacearum has shown that genetic engineering has a profound influence on the performance of this organism in a plant. These data will be of immediate value to microbial ecologists and to regulatory agencies concerned about accidental release of genetically engineered microorganisms.