Small-Molecule Target Engagement in Cells
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Updated: Mar 23, 2026

Identification of Small Molecule-binding Proteins in a Native Cellular Environment by Live-cell Photoaffinity Labeling
Published on: September 20, 2016
Marc Schürmann1, Petra Janning1, Slava Ziegler1
1Department of Chemical Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany.
Abstract:
Monitoring how, when, and where small molecules engage their targets inside living cells is a critical step in chemical biology and pharmacological research, because it enables compound efficacy and confirmation of mode of action to be assessed. In this mini-review we summarize the currently available methodologies to detect and prove direct target engagement in cells and offer a critical view of their key advantages and disadvantages. As the interest of the field shifts toward discovery and validation of high-quality agents, we expect that efforts to develop and refine these types of methodologies will also intensify in the near future.
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