2XK2: Structure Of Hsp90 With Small Molecule Inhibitor Bound

Inhibitors of the chaperone Hsp90 are potentially useful as chemotherapeutic agents in cancer. This paper describes an application of fragment screening to Hsp90 using a combination of NMR and high throughput X-ray crystallography. The screening identified an aminopyrimidine with affinity in the high micromolar range and subsequent structure-based design allowed its optimization into a low nanomolar series with good ligand efficiency. A phenolic chemotype was also identified in fragment screening and was found to bind with affinity close to 1 mM. This fragment was optimized using structure based design into a resorcinol lead which has subnanomolar affinity for Hsp90, excellent cell potency, and good ligand efficiency. This fragment to lead campaign improved affinity for Hsp90 by over 1,000,000-fold with the addition of only six heavy atoms. The companion paper (DOI: 10.1021/jm100060b) describes how the resorcinol lead was optimized into a compound that is now in clinical trials for the treatment of cancer.
PDB ID: 2XK2Download
MMDB ID: 84518
PDB Deposition Date: 2010/7/7
Updated in MMDB: 2010/09
Experimental Method:
x-ray diffraction
Resolution: 1.95  Å
Source Organism:
Similar Structures:
Biological Unit for 2XK2: monomeric; determined by author and by software (PISA)
Molecular Components in 2XK2
Label Count Molecule
Protein (1 molecule)
Heat Shock Protein HSP 90-alpha(Gene symbol: HSP90AA1)
Molecule annotation
Chemicals (2 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB