Shirabe Tomoo, Ito Kyoko, Yoshimura Etsuro
Department of Applied Biological Chemistry, School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1, Yayoi, Bunkyo, Tokyo 113-8657, Japan.
Anal Chem. 2008 Dec 1;80(23):9360-2. doi: 10.1021/ac801741b.
A novel method has been devised for the determination of phytochelatins (PCs), heavy-metal-tolerant peptides produced by higher plants and algae. The method is based on the facts that fluorescence of bathocuproine disulfonate (BCS) is quenched by Cu(I) ions as a result of Cu(I)-BCS complex formation and that PCs compete with BCS for Cu(I). Detection of PCs via recovered fluorescence of BCS using the Cu(I)-BCS complex as a postcolumn reagent, following separation of peptides on an octyldecylsilane column, demonstrated a highly sensitive method for determination of PCs. PCs in the primitive red alga, Cyanidioschyzon merolae, grown in the presence or absence of added Cd(II) were successfully determined by this protocol. Unlike other methods for the determination of PCs, which rely on the SH groups in the peptides, the proposed method is unique in that detection is based on the chemical nature of PCs, which favors the formation of complexes with Cu(I). In this context, the new method yields chromatograms based on the strength of binding Cu(I) ions.
已设计出一种新方法用于测定植物螯合肽（PCs），即高等植物和藻类产生的重金属耐受肽。该方法基于以下事实：二磺酸 bathocuproine（BCS）的荧光由于形成 Cu（I）-BCS 络合物而被 Cu（I）离子淬灭，并且 PCs 与 BCS 竞争 Cu（I）。在十八烷基硅烷柱上分离肽后，使用 Cu（I）-BCS 络合物作为柱后试剂，通过恢复的 BCS 荧光检测 PCs，证明了一种测定 PCs 的高灵敏度方法。通过该方案成功测定了在添加或不添加 Cd（II）的情况下生长的原始红藻 Cyanidioschyzon merolae 中的 PCs。与其他依赖肽中 SH 基团测定 PCs 的方法不同，所提出的方法的独特之处在于检测基于 PCs 的化学性质，这有利于与 Cu（I）形成络合物。在此背景下，新方法根据结合 Cu（I）离子的强度生成色谱图。
