Nanopore-Based Detection of Protein Posttranslational Modifications.

Posttranslational modifications (PTMs) are crucial regulators of protein functions, localization, and interactions, contributing to nearly all aspects of cellular physiology. Conventional analytical approaches, such as mass spectrometry (MS), have achieved high sensitivity and coverage, yet they often require complex sample preparation, enrichment, and high-end instrumentation. Nanopore has emerged as a promising single-molecule approach for PTM detection, offering label-free, high-throughput, and potentially portable analysis capabilities. Despite remarkable progress in nucleic acid sequencing with nanopores, its application to PTM detection in proteins remains at an early stage, hindered by challenges in protein capture, controlled unfolding, the interplay of sequence and structural heterogeneity, and diverse PTM chemistries. In this chapter, we summarize the current landscape of nanopore-based PTM identification and describe two experimental strategies that represent the most feasible near-term workflows for translating nanopore technology into practical protein PTM analysis.