Krämer U, Chardonnens A N
Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany.
Appl Microbiol Biotechnol. 2001 Jun;55(6):661-72. doi: 10.1007/s002530100631.
The use of plants to clean-up soils contaminated with trace elements could provide a cheap and sustainable technology for bioremediation. Field trials suggested that the rate of contaminant removal using conventional plants and growth conditions is insufficient. The introduction of novel traits into high biomass plants in a transgenic approach is a promising strategy for the development of effective phytoremediation technologies. This has been exemplified by generating plants able to convert organic and ionic forms of mercury into the less toxic, volatile, elemental mercury, a trait that occurs naturally only in some bacteria and not at all in plants. The engineering of a phytoremediator plant requires the optimization of a number of processes, including trace element mobilization in the soil, uptake into the root, detoxification and allocation within the plant. A number of transgenic plants have been generated in an attempt to modify the tolerance, uptake or homeostasis of trace elements. The phenotypes of these plants provide important insights for the improvement of engineering strategies. A better understanding, both of micronutrient acquisition and homeostasis, and of the genetic, biochemical and physiological basis of metal hyperaccumulation in plants, will be of key importance for the success of phytoremediation.
利用植物清理受微量元素污染的土壤可为生物修复提供一种廉价且可持续的技术。田间试验表明，使用传统植物和生长条件去除污染物的速率不足。通过转基因方法将新性状引入高生物量植物是开发有效植物修复技术的一种有前景的策略。这已通过培育能够将有机汞和离子汞形式转化为毒性较小的挥发性元素汞的植物得到例证，这种特性仅在某些细菌中自然存在，而在植物中根本不存在。植物修复植物的工程改造需要优化许多过程，包括土壤中微量元素的活化、根系吸收、解毒以及在植物体内的分配。为了改变对微量元素的耐受性、吸收或体内平衡，已经培育出了一些转基因植物。这些植物的表型为改进工程策略提供了重要见解。更好地理解微量营养素的获取和体内平衡，以及植物中金属超积累的遗传、生化和生理基础，对于植物修复的成功至关重要。
