Sample preparation for structural mass spectrometry via polyacrylamide gel electrophoresis

Area of Science:

• Biochemistry and Analytical Chemistry
• Proteomics and Structural Biology

Background:

• Mass spectrometry (MS) is a sensitive analytical technique for protein detection and identification.
• Emerging applications of MS include large-scale in vivo protein structure analysis.
• Top-down MS and cross-linking MS provide insights into intact protein structures and complex conformations.

Purpose of the Study:

• To describe elemental technologies for Polyacrylamide gel electrophoresis (PAGE)-based sample prefractionation for structural mass spectrometry.
• To present efficient methods for intact protein recovery and rapid enzymatic digestion of gel-recovered proteins.
• To provide detailed experimental protocols and examples for structural mass spectrometry applications.

Main Methods:

• Utilized Polyacrylamide gel electrophoresis (PAGE) as a high-resolution sample prefractionation tool.
• Employed Passively Eluting Proteins from Polyacrylamide gels as Intact species for Mass Spectrometry (PEPPI-MS) for efficient intact protein recovery.
• Applied Anion-Exchange disk-assisted Sequential sample Preparation (AnExSP) for rapid enzymatic digestion using solid-phase extraction.

Main Results:

• Demonstrated PAGE as an effective prefractionation method for obtaining detailed structural information in mass spectrometry workflows.
• PEPPI-MS enables highly efficient recovery of intact proteins from polyacrylamide gels.
• AnExSP provides a rapid enzymatic digestion protocol for gel-recovered proteins suitable for structural mass spectrometry.

Conclusions:

• PAGE-based sample prefractionation is crucial for advanced structural mass spectrometry.
• PEPPI-MS and AnExSP are valuable elemental technologies that enhance the analysis of protein structures and complexes.
• These methods facilitate detailed structural mass spectrometry analysis of complex biological samples.