超积累植物体内的小分子螯合物质及其生理作用

螯合效应是超积累植物忍耐重金属的重要机理之一，不同的超积累植物对不同的重金属胁迫其体内产生的螯合物质不同。目前在超积累植物中发现的螯合物质以其分子量大小可分为两大类，即：草酸、组氨酸、苹果硫、柠檬酸及谷胱甘肽等小分子物质和金属硫蛋白、植物络合素、金属结合体及金属结合蛋白等大分子物质。本文就超积累植物体内的小分子螯合物质及其生理作用作一概述。

Low Molecular Weight Chelating Compounds and Their Physiological Function in Hyperaccumulator

A review with 38 references is given on the low molecular weight chelating compounds and their physiological function in hyperaccumulators . Chelation is one of the important mechanisms of hyper-accumulator to tolerant heavy metal toxicity. Different kinds of hyperaccumulators can synthesize different chelating compounds to particular heavy metal stress . There are two groups of chelating compounds found in hyperaccumulators, e.g. low molecular weight compounds including oxalic acid, histidine, malic ac-id, citric acid, and glutathione (GSH), and high molecular weight compounds including metallothio-nein (MT), phytochelatin (PC), metal-binding compound (MBC) and metal-binding protein (MBP)