The Purification and Rapid Identification of Heavy Metal-binding Peptides of Water Hyacinth

This paper studies the rapid identification of heavy metal-binding peptides (phytochelatin) by taking Water Hyacinth as a model plant. Plants were cultured in water containing 2 μg/ml Cd2+ for 13 days. The Sephadex G-50 chromatography of root extract under low salt concentration (0. 01 mol/L PBS) gave a Cd-binding peak with MW of 10 ,000 determined by SEC HPLC. After oxidation with performic acid, its SEC HPLC molecular weight decreased to below 1300 and the reverse phase HPLC showed one peptide peak, whose amino acid composition is the same as that of the sample never undertaking oxidation, and (Glu/Gln):Cys:Gly=2:2:1. According to the general structure of phytochelatin (γ-Glu-Cys)n-Gly, n is 2 in this case. The protocol including the sequential steps of Sephadex G-50 chromatography→performic acid oxidation→reverse phase HPLC→amino acid analysis is a rapid and effective method to identify the existence of phytochelatin and determine its values of n.     

^6^0Coγ射线辐照诱发的苯水体系发光特性的实验研究

￣（６０）Ｃｏ　γ射线辐照诱发的苯水体系发光特性的实验研究王英彦，王继光（国家城市环境污染控制工程技术研究中心，北京１０００３７）马玉琴，苏震，赵克俭，张仲纶，郑雁珍，刘成祥（中国科学院生物物理所，北京１００１０１）１引言在一般条件下，苯和水或两者混...     

凤眼莲重金属螯合肽的分离纯化及快速鉴定

本文以凤眼莲为模式植物,研究植物重金属螯合肽的分离纯化及其快速鉴定。凤眼莲放养在含2μg/ml Cd~(2+)的水中诱导13天。组织抽提液在低盐浓度下(0.01mol/L PBS)经Sephadex G-50柱层析,得到一个含Cd的巯基峰,凝胶过滤HPLC表观分子量为10000。将此巯基峰用过甲酸氧化,凝胶过滤HPLC表观分子量降至1300以下,经反相HPLC分析只有一个肽峰。G-50 Cd-巯基峰与反相HPLC肽峰的氨基酸组成相同,均为(Glu/Gln):Cys:Gly=2:2:1。依据重金属螯合肽的通式(γ-Glu-Cys)_n-Gly,可知n=2。过甲酸氧化后,反相HPLC和氨基酸组成偶联分析是鉴定是否为重金属结合肽以及其n值的快速有效的方法。