Engineering Enhanced Plants for Arsenic Remediation

描述(申请人提供)：砷是美国最严重的环境污染物之一。传统的砷修复方法包括挖掘受污染的土壤并将其处置在危险废物垃圾填埋场。这种方法劳动密集度高，成本高，特别是对于大型站点。另一种修复技术是植物修复，即利用植物从受污染的土壤或水中去除毒素，并将毒素浓缩在与环境相比的生物质中。Edenspace是使用植物从受污染的土壤或水中修复砷的行业领先者，并在全国各地的许多地点开展工作。砷植物修复目前使用的是一种富砷的蕨类植物。虽然这种多年生热带植物在土壤中积累和去除砷是有效的，但它的使用受到限制，因为需要移植幼苗而不是从种子中生长植物，以及它对低于-5℃的持续温度的低耐受性。开发更广泛地适应类似积累砷能力的替代作物将提高解决环境砷问题的能力。对于这个STTR项目，Edenspace及其研究伙伴马萨诸塞州大学(UMassusetts)提议开发用于砷植物修复的增强型植物。许多植物和微生物基因已经被分离和鉴定，在模式植物拟南芥中，可以使砷的耐受性和吸收增加四倍。由于这种植物体积小，修复的商业潜力很低，该团队将利用转基因对一种高生物量、非食用作物甘蓝型油菜进行生物工程。在第一阶段，Edenspace将确认转基因油菜表现出与转基因拟南芥相同的耐砷和吸收表型，这将导致在第二阶段进行小规模田间示范。与公共卫生相关：砷是一种剧毒物质，可以自然存在于环境中，也可以通过人类活动集中在受污染的地点，并对人类和野生动物造成重大的健康问题。该项目旨在开发一种有效和经济的技术，能够利用植物从环境中去除砷，并降低公众接触砷的风险。

DESCRIPTION (provided by applicant): Arsenic is one of the most serious environmental contaminants in the United States. The traditional method for arsenic remediation involves excavating the contaminated soil and disposing it in hazardous waste landfills. This method is highly labor intensive and costly, especially for large sites. An alternative remediation technique is phytoremediation, the use of plants to remove toxins from contaminated soils or water and concentrate the toxins in the biomass compared to the environment. Edenspace is an industry leader in the use of plants to remediate arsenic from contaminated soil or water and has worked on numerous sites across the country. Arsenic phytoremediation currently uses an arsenic-accumulating fern plant. While this perennial tropical plant is effective is accumulating and removing arsenic from the soil, its use is limited by the need to transplant young plants rather than growing plants from seed, and by its low tolerance for sustained temperatures below -5¿C. Development of alternative crops that are more widely adapted with similar abilities to accumulate arsenic will provide enhanced capabilities to address the problem of environmental arsenic. For this STTR project Edenspace and its research partner, the University of Massachusetts (UMass) propose to develop enhanced plants for arsenic phytoremediation. A number of plant and microbial genes have been isolated and characterized that confer fourfold increases in arsenic tolerance and uptake in the model plant Arabidopsis thaliana. Because this plant has low commercial potential for remediation due to its small size, the team will bioengineer a highbiomass, non-food variety of a row crop, Brassica napus, with the transgenes. In Phase I, Edenspace will confirm that the transgenic B. napus shows the same arsenic tolerance and uptake phenotype observed in transgenic Arabidopsis, which will lead in Phase II to a small scale field demonstration. PUBLIC HEALTH RELEVANCE: Arsenic is a highly toxic substance found either naturally in the environment or concentrated by human activity at contaminated sites, and provides significant health concerns to humans and wildlife. This project intends to develop an effective and economical technology capable of removing arsenic from the environment using plants and lowering the public's risk of exposure to arsenic.