title: Identification of Two Novel Modifications at Tryptophan Residues.
abstract: Protein post-translational modifications (PTMs) play important roles in cellular physiology. Mass spectrometry (MS) has been developed into a powerful tool to identify all possible protein modifications. Herein, we describe our efforts to deduce the structures of two unknown modifications at tryptophan (Trp) residues (W + 92 Da and W + 108 Da). The two modifications were further confirmed by aligning the MS/MS fragmentation of synthetic peptide with in-vivo peptide identified. Finally, the mimic experiment elucidated how two Trp modifications occur. This study, therefore, expands current knowledge of Trp modifications.
authors.affiliation: Department of Chemistry, Nankai University, Tianjin, 300071, People's Republic of China.
authors.forename: Shuzhen
authors.initials: S
authors.lastname: Zheng
authors.affiliation: Department of Chemistry, Nankai University, Tianjin, 300071, People's Republic of China. zhangkai@nankai.edu.cn.|Department of Biochemistry and Molecular Biology & Tianjin Key Laboratory of Medical Epigenetics, Tianjin Medical University, Tianjin, 300070, People's Republic of China. zhangkai@nankai.edu.cn.
authors.forename: Kai
authors.initials: K
authors.lastname: Zhang
authors.affiliation: Department of Biochemistry and Molecular Biology & Tianjin Key Laboratory of Medical Epigenetics, Tianjin Medical University, Tianjin, 300070, People's Republic of China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Tian
authors.affiliation: Department of Chemistry, Nankai University, Tianjin, 300071, People's Republic of China.
authors.forename: Xiwen
authors.initials: X
authors.lastname: He
authors.affiliation: Department of Chemistry, Nankai University, Tianjin, 300071, People's Republic of China. ykzhang@dicp.ac.cn.|National Chromatographic Research and Analysis Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, People's Republic of China. ykzhang@dicp.ac.cn.
authors.forename: Yukui
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D011499:Protein Processing, Post-Translational; D040901:Proteomics; D053719:Tandem Mass Spectrometry / Q000379:methods*; D014364:Tryptophan / Q000032:analysis / Q000737:chemistry*
chemical_list: D014364:Tryptophan
keywords: Mass spectrometry; Post-translational modifications; Proteomics; Tryptophan modifications