4TYA: An Ligand-observed Mass Spectrometry-based Approach Integrated Into The Fragment Based Lead Discovery Pipeline

In fragment-based lead discovery (FBLD), a cascade combining multiple orthogonal technologies is required for reliable detection and characterization of fragment binding to the target. Given the limitations of the mainstream screening techniques, we presented a ligand-observed mass spectrometry approach to expand the toolkits and increase the flexibility of building a FBLD pipeline especially for tough targets. In this study, this approach was integrated into a FBLD program targeting the HCV RNA polymerase NS5B. Our ligand-observed mass spectrometry analysis resulted in the discovery of 10 hits from a 384-member fragment library through two independent screens of complex cocktails and a follow-up validation assay. Moreover, this MS-based approach enabled quantitative measurement of weak binding affinities of fragments which was in general consistent with SPR analysis. Five out of the ten hits were then successfully translated to X-ray structures of fragment-bound complexes to lay a foundation for structure-based inhibitor design. With distinctive strengths in terms of high capacity and speed, minimal method development, easy sample preparation, low material consumption and quantitative capability, this MS-based assay is anticipated to be a valuable addition to the repertoire of current fragment screening techniques.
PDB ID: 4TYADownload
MMDB ID: 129060
PDB Deposition Date: 2014/7/8
Updated in MMDB: 2017/10
Experimental Method:
x-ray diffraction
Resolution: 2.94  Å
Source Organism:
Similar Structures:
Biological Unit for 4TYA: tetrameric; determined by author
Molecular Components in 4TYA
Label Count Molecule
Proteins (4 molecules)
Molecule annotation
Chemicals (4 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB