Mou Ren-Xiang, Cao Zhao-Yun, Lin Xiao-Yan, Wu Li, Cao Zhen-Zhen, Zhu Zhi-Wei, Chen Ming-Xue
China National Rice Research Institute, No. 359 Tiyuchang Rd., Hangzhou, Zhejiang, 310006, P.R. China.
Rapid Commun Mass Spectrom. 2016 Aug 30;30(16):1891-900. doi: 10.1002/rcm.7669.
The identification and quantification of phytochelatins (PCs) and their derivatives are important to understand their roles in plant growth and development. A method couplling high-performance liquid chromatography with hybrid linear ion trap Orbitrap mass spectrometry (HPLC-LTQ/Orbitrap) was developed to screen PCs that have the same characteristic product ions. This approach was used for the fragmentation pattern analysis of glutathione (GSH) and PC standards, which allowed identification of the fragmentation pathways of their derivatives isolated from rice roots, stems and leaves.
In this study, we developed a method to detect and identify PCs and their derivatives in rice based on HPLC/LTQ-Orbitrap. Spectrum interpretation and MS/MS fragmentation patterns of PCs provide sufficient information to discover the novel PC derivatives. This approach includes precursor ion scan and product ion scan to detect and character the novel PC derivatives.
Based on HCD-MS/MS fragmentation patterns, four PCs and 18 PC derivatives were identified. Among them, seven PC derivatives, i.e., iso-PC2 (Asn), iso-PC3 (Asn), iso-PC2 (Cys), des-γGlu-iso-PC3 (Ser), des-Cys-iso-PC2 (Glu), des-Cys-iso-PC3 (Glu) and des-Cys-iso-PC4 (Glu), have not been previously reported. This method was validated by profiling GSH, PCs and PC derivatives in rice. Preliminary results revealed that PCs and their derivatives, except GSH, are markedly induced by Cd treatment.
The HPLC/LTQ-Orbitrap method was successfully developed for the identification of PCs and their derivatives. The C-terminal linked to Gly is replaced with Glu, Ser, Asn, Gln or Cys, thereby creating a family of chemicals that share several structural properties. This technique could be particularly useful for investigators studying plant metabolomics. Copyright © 2016 John Wiley & Sons, Ltd.
植物螯合肽（PCs）及其衍生物的鉴定和定量对于理解它们在植物生长发育中的作用至关重要。开发了一种将高效液相色谱与混合线性离子阱轨道阱质谱联用（HPLC-LTQ/Orbitrap）的方法，以筛选具有相同特征产物离子的植物螯合肽。该方法用于谷胱甘肽（GSH）和植物螯合肽标准品的碎片模式分析，从而确定从水稻根、茎和叶中分离出的其衍生物的碎片途径。
在本研究中，我们开发了一种基于HPLC/LTQ-Orbitrap检测和鉴定水稻中植物螯合肽及其衍生物的方法。植物螯合肽的光谱解析和MS/MS碎片模式提供了足够的信息来发现新型植物螯合肽衍生物。该方法包括前体离子扫描和产物离子扫描，以检测和表征新型植物螯合肽衍生物。
基于HCD-MS/MS碎片模式，鉴定出4种植物螯合肽和18种植物螯合肽衍生物。其中，7种植物螯合肽衍生物，即异植物螯合肽2（Asn）、异植物螯合肽3（Asn）、异植物螯合肽2（Cys）、去γ-谷氨酰-异植物螯合肽3（Ser）、去半胱氨酸-异植物螯合肽2（Glu）、去半胱氨酸-异植物螯合肽3（Glu）和去半胱氨酸-异植物螯合肽4（Glu），此前尚未见报道。该方法通过分析水稻中的谷胱甘肽、植物螯合肽和植物螯合肽衍生物进行了验证。初步结果表明，除谷胱甘肽外，植物螯合肽及其衍生物在镉处理下显著诱导产生。
成功开发了HPLC/LTQ-Orbitrap方法用于鉴定植物螯合肽及其衍生物。与甘氨酸相连的C末端被谷氨酸、丝氨酸、天冬酰胺、谷氨酰胺或半胱氨酸取代，从而产生了一系列具有若干结构特性的化学物质。该技术对研究植物代谢组学的研究人员可能特别有用。版权所有©201六年约翰威立父子有限公司。
