Activity-Based Protein Profiling with Natural Product-Derived Chemical Probes in Human Cell Lysates

: Bioreactive natural products represent versatile starting points for the development of structurally unique activity-based probes. In the present protocol, we describe the workflow for an activity-based protein profiling (ABPP) experiment with an alkyne-tagged natural product derivative. Our protocol includes experimental procedures for in vivo labeling, sample preparation and 2-step (click chemistry) visualization and sample preparation for mass spectrometry-based target identification.