Chiral recognition of phenylalanine(Phe) was achieved in the gas phase by electrospray ionization Q-TOF tandem mass spectrometry.In this method,two central ions,i.e.proton and divalent copper,were used and chiral crow...Chiral recognition of phenylalanine(Phe) was achieved in the gas phase by electrospray ionization Q-TOF tandem mass spectrometry.In this method,two central ions,i.e.proton and divalent copper,were used and chiral crown ether,(+)-2,3,11,12-tetracarboxylic acid-18-crown-6(18-C-6-TCA),was used as a chiral host.Dimeric complexes were readily formed by electrospray ionization of a methanol/water(50/50,V/V) solution containing central ions,Phe and 18-C-6-TCA.The dimeric complex included proton-bound(18-C-6-TCA)(Phe)H+ and copper-bound deprotonated [Cu2+(18-C-6-TCA)(Phe)-H]+ ions were mass selected and then collided with Ar in the CID experiments.The chiral recognition capability of these complexes was evaluated using the relative abundance of daughter ion to parent ion.A higher degree of chiral recognition ability was observed with Cu2+ compared to that of H+.Different central ions exhibited distinctive dissociation pathways and unique chiral recognition characteristics.The chiral recognition mechanism was also discussed in detail with the help of the structure of copper-bound complex predicted by theoretical calculation.展开更多
文摘蛋白质组学的兴起带动了质谱技术的快速发展,而质谱技术的进步则拓宽了蛋白质组学研究问题的广度.最近10年内,肽段或完整蛋白质在质谱仪中的裂解技术——电子捕获裂解(electron capture dissociation,ECD)与电子转运裂解(electron transfer dissociation,ETD)逐渐发展起来.ECD和ETD在蛋白质组学中的应用,特别是在蛋白质的翻译后修饰鉴定和"自顶而下(Top-down)"的完整蛋白质裂解研究中已经展示出了诱人的前景.对ECD和ETD的基本原理、质谱特点、仪器实现、数据解析算法与软件开发,以及在蛋白质组学中的应用进展等方面进行了比较系统全面的阐述,并对当前的研究问题、面临的技术挑战与未来的发展趋势等方面作了深入剖析.
文摘Chiral recognition of phenylalanine(Phe) was achieved in the gas phase by electrospray ionization Q-TOF tandem mass spectrometry.In this method,two central ions,i.e.proton and divalent copper,were used and chiral crown ether,(+)-2,3,11,12-tetracarboxylic acid-18-crown-6(18-C-6-TCA),was used as a chiral host.Dimeric complexes were readily formed by electrospray ionization of a methanol/water(50/50,V/V) solution containing central ions,Phe and 18-C-6-TCA.The dimeric complex included proton-bound(18-C-6-TCA)(Phe)H+ and copper-bound deprotonated [Cu2+(18-C-6-TCA)(Phe)-H]+ ions were mass selected and then collided with Ar in the CID experiments.The chiral recognition capability of these complexes was evaluated using the relative abundance of daughter ion to parent ion.A higher degree of chiral recognition ability was observed with Cu2+ compared to that of H+.Different central ions exhibited distinctive dissociation pathways and unique chiral recognition characteristics.The chiral recognition mechanism was also discussed in detail with the help of the structure of copper-bound complex predicted by theoretical calculation.
