Navigating Challenges in Mass Spectrometry Analysis of Endogenous and Synthetic Protein Modifications.

Area of Science:

• Biochemistry
• Proteomics
• Analytical Chemistry

Background:

• Mass spectrometry (MS)-based analysis of post-translational modifications (PTMs) is vital for understanding protein regulation and identifying disease biomarkers.
• Chemical proteomic strategies leverage PTM-focused workflows to measure small-molecule probe engagement for ligand discovery.

Purpose of the Study:

• To provide an overview of MS-based PTM analysis workflows, from data acquisition to processing.
• To highlight the influence of modification-specific physicochemical properties on PTM detection and identification.
• To discuss challenges and recent advances in PTM identification and validation.

Main Methods:

• Review of LC-MS/MS acquisition and post-acquisition data processing strategies.
• Discussion of analytical challenges including fragmentation behavior and site localization.
• Summary of recent advances in acquisition techniques and computational tools.
• Description of analytical validation approaches like metabolic labeling.

Main Results:

• MS-based PTM profiling offers insights into protein regulation and disease targets.
• Modification-specific properties significantly impact PTM detection.
• Advances in MS and computational tools enhance PTM identification confidence.
• Analytical validation methods are crucial for reliable PTM data.

Conclusions:

• MS-based PTM profiling is a powerful tool with specific considerations, capabilities, and limitations.
• Effective interpretation of PTM datasets is key for downstream validation studies.
• This review provides a framework for understanding and utilizing MS-based PTM data.