A novel strategy for arsenic phytoremediation

砷植物修复的新策略

基本信息

批准号：
10369022
负责人：
Om Parkash Dhankher
金额：
$ 20万
依托单位：
UNIVERSITY OF MASSACHUSETTS AMHERST
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-03-09 至 2025-12-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10369022
关键词：
Address Amendment Arsenic Assimilations Binding Biological Biological Availability Biomass Characteristics Crambe abyssinica Culture Media Development Drug Metabolic Detoxication Engineering Food Chain Future Gene Expression Gene Transfer Genes Genetic Genetic Engineering Goals High Pressure Liquid Chromatography Human Hydroponics Inductively Coupled Plasma Mass Spectrometry Investigation Knowledge Laboratories Metals Methods Oils Organ Outcome Performance Physiological Processes Plant Leaves Plant Roots Plants Process Public Health RNA Interference Roentgen Rays Seeds Site Soil Spectrum Analysis Structure Sulfur Testing Tissues United States Department of Agriculture Vacuole absorption arsenate reductase base cost effective effectiveness evaluation field study global health knock-down nanoparticle novel strategies overexpression oxidation remediation screening surface coating tissue culture toxic metal uptake

项目摘要

Project Summary: Arsenic contamination in the food chain is a global health problem and causes damage to most human organs. A significant need exists to develop approaches for addressing environmental arsenic. The long term goal is to develop a plant-based phytoremediation approach for contaminated land that is cost-effective and ecologically friendly as an alternative to conventional remediation methods. The objective of this study is to develop a genetics-based phytoremediation strategy for arsenic uptake, translocation, detoxification, and hyperaccumulation into the fast-growing, high biomass, non-food crop Crambe abyssinica. Nanosulfur will be utilized to modulate the bioavailability and phytoextraction of As from soil and to increase the storage capacity via enhanced sulfur assimilation. The engineered Crambe will be evaluated for removing arsenic from the soil in laboratory, greenhouse, and field conditions. Our central hypothesis is that organ-specific expression of genes, which control the transport, oxidation state, and binding of As, can be tuned to yield efficient extraction and hyperaccumulation into above-ground plant tissues. To test our hypothesis, we propose the following specific aims. 1) Genetically engineer Crambe abyssinica lines for co-expressing bacterial ArsC, gECS, and AtABCC1 and RNAi suppression of endogenous arsenate reductase CaACR2; 2) Evaluate the engineered Crambe lines for metal(loids) tolerance and accumulation; 3) Synthesize and apply nanosulfur to modulate the bioavailability, phytoextraction, and accumulation of toxic metal(loids); and 4) Conduct a pilot field study of engineered Crambe lines for phytoextraction on a contaminated site. After initial screening in tissue culture media supplemented with metals, the best performing quadruple gene stacked (ArcS+gECS+AtABCC1+CaACR2Ri) Crambe lines with wild type controls will be tested using contaminated soils with arsenic as well as co-contaminants in greenhouse. A pilot field-scale study will then be carried out at a site contaminated with arsenic. The soil will be extensively characterized, and analysis for metal content and arsenic speciation will be determined using ICP/MS, HPLC- ICP/MS as well as XANES (X-ray Absorption Near-Edge Spectroscopy). Last, soil amendments with engineered nanosulfur will be used to evaluate the impacts on soil structure and contaminant availability and phytoextraction. Nanosulfur will also be foliarly applied to plants to increase the metal storage capacity via enhanced sulfur assimilation. The expected outcome of this project is a mechanistic understanding of the biogeochemical and plant processes of arsenic remediation that connects key soil characteristics with the efficiency of phytoextraction and hyperaccumulation of arsenic. The results will have an immediate and important positive impact because the knowledge generated from this study will enable efficient and effective phytoremediation approaches to minimize or remove arsenic contamination in the food chain and enhance public health.

项目概要：食物链中的砷污染是一个全球性的健康问题，会对大多数人体器官造成损害。迫切需要开发解决环境砷问题的方法。长期目标是开发一种经济高效且生态环保的基于植物的污染土地植物修复方法作为传统修复方法的替代方案。本研究的目的是开发一种基于遗传学的植物修复策略，用于砷的吸收、易位、解毒和超积累到快速生长、高生物量的非粮食作物海甘蓝中。纳米硫将用于调节土壤中砷的生物利用度和植物提取并增加存储容量通过增强硫同化。工程化的 Crambe 将在 2019 年评估其从土壤中去除砷的能力。实验室、温室和现场条件。我们的中心假设是基因的器官特异性表达，它控制 As 的运输、氧化态和结合，可以进行调整以产生有效的提取和超积累到地上植物组织中。为了检验我们的假设，我们提出以下具体建议目标。 1) 对海甘蓝系进行基因改造，共表达细菌 ArsC、gECS 和 AtABCC1 RNAi 抑制内源性砷酸还原酶 CaACR2； 2) 评估工程化的 Crambe 生产线金属（类）耐受性和积累； 3）合成并应用纳米硫来调节生物利用度，植物提取和有毒金属（类物质）的积累； 4) 对工程海甘蓝进行试点实地研究在污染场地进行植物提取的生产线。在补充了组织培养基的初步筛选后金属，表现最好的四重基因堆叠 (ArcS+gECS+AtABCC1+CaACR2Ri) Crambe 系与野生将使用受砷污染的土壤以及温室中的共污染物来测试类型控制。一个随后将在受砷污染的地点进行试点实地研究。土壤将广泛表征，并使用 ICP/MS、HPLC 确定金属含量和砷形态分析 ICP/MS 以及 XANES（X 射线吸收近边光谱）。最后，通过工程改造土壤纳米硫将用于评估对土壤结构、污染物可用性和植物提取的影响。纳米硫还将喷施至植物叶面，通过增强硫来提高金属储存能力同化。该项目的预期成果是对生物地球化学和将关键土壤特征与植物提取效率联系起来的砷修复植物过程和砷的过度积累。结果将产生直接而重要的积极影响，因为这项研究产生的知识将使高效和有效的植物修复方法成为可能最大限度地减少或消除食物链中的砷污染并增强公众健康。