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Updated: Jan 27, 2026

Workflow and Tools for Crystallographic Fragment Screening at the Helmholtz-Zentrum Berlin
Published on: March 3, 2021
Crystallographic screening using ultra-low-molecular-weight ligands to guide drug design
Marc O'Reilly1, Anne Cleasby1, Thomas G Davies1
1Astex Pharmaceuticals,436 Cambridge Science Park, Milton Road, Cambridge, CB4 0QA, UK.
Abstract:
We present a novel crystallographic screening methodology (MiniFrags) that employs high-concentration aqueous soaks with a chemically diverse and ultra-low-molecular-weight library (heavy atom count 5-7) to identify ligand-binding hot and warm spots on proteins. We propose that MiniFrag screening represents a highly effective method for guiding optimisation of fragment-derived lead compounds or chemical tools and that the high screening hit rates reflect enhanced sampling of chemical space.
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