Laboratory of Bioorganic Chemistry, Department of Chemistry, University of Konstanz, Konstanz, Germany.
J Am Soc Mass Spectrom. 2010 Feb;21(2):215-9. doi: 10.1016/j.jasms.2009.10.004. Epub 2009 Oct 12.
An efficient approach in combinatorial chemistry is the synthesis of one-bead-one-compound peptide libraries. In contrast to synthesis and functional screening, which is performed in a largely automated manner, structure determination has been frequently laborious and time-consuming. Here we report an approach for de novo sequencing of peptides on single beads by matrix-assisted laser desorption/ionization Fourier transform ion cyclotron resonance (MALDI-FTICR) tandem mass spectrometry, using a resin with a photolinker for solid-phase peptide synthesis. Upon sorting out single beads, an efficient sample preparation on the MALDI target was developed that enables fragmentation upon irradiation of the bead-matrix mixture with the ultraviolet (UV)-MALDI laser, with enhanced yield of sequence-specific fragment ions at increased laser energy. This approach is illustrated by sequence determinations of two peptides from a library with sequences varying in a single amino acid; the feasibility with tandem-MS procedures and fragment ion assignment was ascertained by sustained off-resonance irradiation/collision induced dissociation (SORI/CID) and infrared multiphoton dissociation (IRMPD) fragmentation.
组合化学中的一种有效方法是合成单珠一单化合物肽库。与主要以自动化方式进行的合成和功能筛选相比，结构测定通常既费力又耗时。在这里，我们报告了一种通过基质辅助激光解吸/电离傅里叶变换离子回旋共振（MALDI-FTICR）串联质谱法对单个珠上肽进行从头测序的方法，该方法使用带有光连接基团的树脂进行固相肽合成。在对单个珠子进行分类后，开发了一种在 MALDI 靶标上进行高效样品制备的方法，该方法能够在珠-基质混合物用紫外线（UV）-MALDI 激光照射时进行碎裂，从而在增加激光能量时提高序列特异性片段离子的产率。通过对具有单个氨基酸序列变化的文库中的两个肽进行序列测定来说明该方法，通过持续的离共振辐照/碰撞诱导解离（SORI/CID）和红外多光子解离（IRMPD）碎裂来确定串联-MS 程序和片段离子分配的可行性。
