Dissociation of proton-bound complexes reveals geometry and arrangement of double bonds in unsaturated lipids
作者:Huong T. Pham、Matthew B. Prendergast、Christopher W. Dunstan、Adam J. Trevitt、Todd W. Mitchell、Ryan R. Julian、Stephen J. Blanksby
DOI:10.1016/j.ijms.2015.07.006
日期:2015.11
(i.e., cis and trans). In this study, CID performed on proton-bound complexes of fatty acid methyl esters and iodoaniline (and related reagents) reveals unusual fragmentation patterns. CID products are shown to result from proton transfer and are associated with specific structures of the unsaturated lipids. Notably, CID of these complexes can not only distinguish cis- and trans-fatty acid methyl esters
不饱和脂质中的双键位置和立体化学会对生物学特性和活性产生深远的影响,但通过质谱法确定这些特征通常具有挑战性。脂质鉴定的传统技术依赖于碰撞诱导解离 (CID),并且通常无法区分脂质异构体,尤其是那些涉及双键位置和几何形状(即顺式和反式)的异构体。在这项研究中,对脂肪酸甲酯和碘苯胺(及相关试剂)的质子结合复合物进行的 CID 揭示了不寻常的碎片模式。CID 产物被证明是由质子转移产生的,并且与不饱和脂质的特定结构有关。值得注意的是,这些复合物的 CID 不仅可以区分顺式和反式脂肪酸甲酯,但也区分共轭双键排列与非共轭类似物。在此,通过稳定同位素标记研究了支持这种独特 CID 行为的机制,并建议涉及卡宾和自由基中间体。