Key Laboratory of Plant Functional Genomics of the Ministry of Education/Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, College of Agriculture, Yangzhou University, Yangzhou 225009, China; Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/Co-Innovation Center for Modern Production Technology of Grain Crops of Jiangsu Province/Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education, Yangzhou University, Yangzhou 225009, China.
Key Laboratory of Plant Functional Genomics of the Ministry of Education/Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, College of Agriculture, Yangzhou University, Yangzhou 225009, China; College of Agronomy, Qingdao Agricultural University, Qingdao 266109, Shandong, China.
J Hazard Mater. 2022 Jul 5;433:128779. doi: 10.1016/j.jhazmat.2022.128779. Epub 2022 Mar 26.
Nitroaromatic compounds, as the important chemical feedstock, have caused widespread environmental contaminations, and exhibited high toxicity and mutagenic activity to nearly all living organisms. The clean-up of nitroaromatic-contaminated soil and water has long been a major international concern. Here, we uncovered the role of a novel nitroreductase family gene, streptolysin S (SLS)-associated gene B (SagB), in enhancing nitroaromatic tolerance and detoxification of plants, and its potential application in phytoremediation of nitroaromatic contaminations. The expression of both the Arabidopsis and rice SagB genes is significantly induced by multiple hazardous nitroaromatic substances, including explosive pollutant 2,4,6-trinitrotoluene (TNT), natural compound 1-nitropyrene (1-NP) and herbicide pendimethalin (Pen). In vitro and in vivo evidences revealed that plant SagBs possess activities in degradation of these nitroaromatic substances. Arabidopsis and rice transgenic assays suggested that plant SagB genes increase tolerance and detoxification of nitroaromatic through facilitating its transformation to the amino derivative. More importantly, overexpression of plant SagBs increase their ability in TNT uptake, and remove more TNT from the growth culture. Our findings shed novel insights into a plant endogenous nitroreductase-mediated nitroaromatic tolerance and detoxification, and provide a new gene target for phytoremediation of nitroaromatic-contaminated environments.
硝基芳香族化合物作为重要的化学原料，已造成广泛的环境污染，并对几乎所有生物都表现出高毒性和致突变活性。清洁受硝基芳香族化合物污染的土壤和水一直是国际上的主要关注点。在这里，我们揭示了一种新型硝基还原酶家族基因——链球菌溶血素 S（SLS）相关基因 B（SagB）在增强植物对硝基芳香族化合物的耐受性和解毒作用中的作用，及其在植物修复硝基芳香族污染中的潜在应用。拟南芥和水稻 SagB 基因的表达均被多种危险的硝基芳香族物质显著诱导，包括爆炸污染物 2,4,6-三硝基甲苯（TNT）、天然化合物 1-硝基芘（1-NP）和除草剂二甲戊灵（Pen）。体内外证据表明，植物 SagB 具有降解这些硝基芳香族物质的活性。拟南芥和水稻转基因实验表明，植物 SagB 基因通过促进其转化为氨基衍生物来增加对硝基芳香族化合物的耐受性和解毒能力。更重要的是，植物 SagB 的过表达增加了它们对 TNT 的吸收能力，并从生长培养基中去除了更多的 TNT。我们的研究结果为植物内源性硝基还原酶介导的硝基芳香族化合物耐受性和解毒作用提供了新的见解，并为植物修复受硝基芳香族化合物污染的环境提供了新的基因靶点。
