Enhanced endophyte:poplar system for remediation of organic contaminants

说明(申请人提供)：三氯乙烯(TCE)是最常见的地下水污染物之一，是一种已知的肝脏毒素和致癌物质。它已被工业和军方广泛用作金属部件的脱脂剂：根据有毒物质和疾病登记机构的数据，美国有800多个超级基金地点受到三氯乙烯的污染。杨树可以吸收和降解三氯乙烯，由于其生长速度快、根系广泛、土壤吸水率高和易于遗传操作，是修复三氯乙烯和其他有机污染物的诱人植物。虽然用于改善TCE降解的转基因杨树已经成功地进行了田间试验，但仍存在重大的监管和育种障碍，阻碍了这项技术的大规模使用。最近，研究人员确定了生活在植物细胞内的内生菌、共生菌和真菌分解有机污染物和提高非转基因植物的植物修复能力的潜力。与用于植物修复的其他微生物不同，内生菌生活在植物内部，因此预计会在现场更好地坚持下去，只要它们的植物伴侣存活下来，就会继续降解三氯乙烯。莎伦·多蒂博士的实验室是研究内生菌以改善植物生长和健康的先驱之一，在这一领域已经工作了十多年。最近，她的实验室从生长在被三氯乙烯和其他有机污染物污染的地点的杨树上分离出内生菌。其中一些微生物在实验室中生长时表现出很高的三氯乙烯降解率。她的实验室目前正在开发将这些降解TCE的内生菌接种到杨树中的方法，并将与Edenspace合作开展这个SBIR项目，以证明新的杨树/内生植物系统具有比对照杨树更好的TCE植物修复性能。Edenspace还将开发分子标记来识别特定的内生菌，以便在田间测试中确认这些微生物可以在杨树上存活数月。在这个SBIR项目成功完成后，Edenspace将与领先的环境工程公司GeSyntec合作，将这项新技术引入修复行业。 与公共健康相关：三氯乙烯(TCE)是一种已知的致癌物质，由于军事和工业的广泛使用，它是一种重大的环境污染物。杨树已被用作从受污染的地下水中去除TCE的一种天然方法。在这个项目中，来自Edenspace和华盛顿大学的科学家将利用最近发现的可以与杨树一起作用的微生物来极大地提高TCE的去除率。开发这一改进的补救系统将减少人类和野生动物对三氯乙烯的暴露。

DESCRIPTION (provided by applicant): Trichloroethylene (TCE), one of the most common groundwater pollutants, is a known hepatotoxin and carcinogen. It has been widely used by industry and the military as a degreaser for metal parts: according to the Agency for Toxic Substances and Disease Registry, more than eight hundred Superfund sites in the United States are contaminated with TCE. Poplar, which can take up and degrade TCE, is an attractive plant for phytoremediation of TCE and other organic contaminants due to its high growth rate, extensive root system, high rates of water uptake from the soil, and ease of genetic manipulation. While transgenic poplar for improved TCE degradation has been successfully field tested, there are significant regulatory and breeding hurdles preventing the large-scale use of this technology. Recently researchers have determined the potential of endophytes, symbiotic bacteria and fungi that live within plant cells, to break down organic contaminants and improve the phytoremediation capability of non-transgenic plants. Unlike other microbes that have been used for phytoremediation, endophytes live within the plant and therefore are expected to persist better at the site, continuing to degrade TCE as long as their plant partner survives. The laboratory of Dr. Sharon Doty is one of the pioneers in studying endophytes to improve plant growth and health, having worked in this field for over a decade. Recently her laboratory has isolated endophytes from poplar growing in sites contaminated with TCE and other organic pollutants. Some of these microbes exhibit high rates of TCE degradation when grown in the lab. Her laboratory is currently developing methods to inoculate these TCE-degrading endophytes into poplar and will work with Edenspace on this SBIR project to demonstrate that the new poplar/endophyte systems have significantly better TCE phytoremediation performance than control poplar. Edenspace will also develop molecular markers to identify the specific endophytes, in order to confirm in a field test that the microbes can persist in the poplar for months. Upon successful completion of this SBIR project Edenspace will partner with Geosyntec, a leading environmental engineering firm, to introduce this novel technology to the remediation industry. PUBLIC HEALTH RELEVANCE: Trichloroethylene (TCE) is a known carcinogen and significant environmental contaminant as a result of to extensive use by the military and industry. Poplar trees have been used as a natural method to remove TCE from contaminated groundwater. In this project scientists from Edenspace and the University of Washington will utilize recently identified microbes that can act with the poplar to greatly increase TCE removal rates. Development of this improved remediation system will reduce exposure of humans and wildlife to TCE.