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

REU：根土系统中基因工程微生物的生态相互作用

• 批准号: 8705690
• 负责人: Peter Hartel
• 金额: $ 18.62万
• 依托单位: University of Georgia Research Foundation Inc
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-07-15 至 1990-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8705690&HistoricalAwards=false
• 关键词: REU; Ecological; Interactions; Genetically; Engineered

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.

雅典佐治亚大学的彼得·哈特尔博士和他的同事们提议对有关基因工程微生物的几个关键的生态学问题进行研究。微生物在不断变化的土壤环境中生存、生长和相互作用的能力之所以持续存在，是因为微生物主动地水平交换基因来换取这些特征。通过提出一系列问题，研究人员将评估特定基因对根/土壤系统中微生物的生态价值。他们使用基因工程来克隆和操纵青枯假单胞菌中编码内切葡聚糖酶和多聚半乳糖醛酸酶的基因。他们将对编码胞外多糖、蛋白酶和脂肪酶的基因使用相同的技术。这些特定基因的表达缺失将被单独和联合测试，以确定它们对青枯病菌生存、生长的影响，并将这些克隆的基因在土壤和根际转移到番茄(Lycopersica Esculentum)。克隆的基因还将被放入恶臭假单胞菌、铜绿假单胞菌和大肠杆菌中。根际相互作用将通过使用不同孔隙度的膜的根际细胞来评估。通过这种方式，基因工程细菌的微生物竞争力将得到评估。这项研究有望提供关于特定基因对环境中微生物的生态价值的基础知识。青枯菌内切葡聚糖酶和多聚半乳糖醛酸酶基因的初步研究表明，基因工程对青枯病菌在植物中的表现有深远的影响。这些数据将对微生物生态学家和担心基因工程微生物意外释放的监管机构具有立竿见影的价值。