Cross-linking electrochemical mass spectrometry for probing protein three-dimensional structures

Qiuling Zheng, Hao Zhang, Lingying Tong, Shiyong Wu, Hao Chen

Research output: Contribution to journalArticlepeer-review

21 Scopus citations


Chemical cross-linking combined with mass spectrometry (MS) is powerful to provide protein three-dimensional structure information but difficulties in identifying cross-linked peptides and elucidating their structures limit its usefulness. To tackle these challenges, this study presents a novel crosslinking MS in conjunction with electrochemistry using disulfide-bondcontaining dithiobis[succinimidyl propionate] (DSP) as the cross-linker. In our approach, electrolysis of DSP-bridged protein/peptide products, as online monitored by desorption electrospray ionization mass spectrometry is highly informative. First, as disulfide bonds are electrochemically reducible, the crosslinks are subject to pronounced intensity decrease upon electrolytic reduction, suggesting a new way to identify cross-links. Also, mass shift before and after electrolysis suggests the linkage pattern of cross-links. Electrochemical reduction removes disulfide bond constraints, possibly increasing sequence coverage for tandem MS analysis and yielding linear peptides whose structures are more easily determined than their cross-linked precursor peptides. Furthermore, this cross-linking electrochemical MS method is rapid, due to the fast nature of electrochemical conversion (much faster than traditional chemical reduction) and no need for chromatographic separation, which would be of high value for structural proteomics research.

Original languageEnglish (US)
Pages (from-to)8983-8991
Number of pages9
JournalAnalytical Chemistry
Issue number18
StatePublished - Sep 1 2014
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Analytical Chemistry


Dive into the research topics of 'Cross-linking electrochemical mass spectrometry for probing protein three-dimensional structures'. Together they form a unique fingerprint.

Cite this