Structurally Diverse Mitochondrial Branched Chain Aminotransferase (BCATm) Leads with Varying Binding Modes Identified by Fragment Screening

J Med Chem. 2016 Mar 24;59(6):2452-67. doi: 10.1021/acs.jmedchem.5b01607. Epub 2016 Mar 16.


Inhibitors of mitochondrial branched chain aminotransferase (BCATm), identified using fragment screening, are described. This was carried out using a combination of STD-NMR, thermal melt (Tm), and biochemical assays to identify compounds that bound to BCATm, which were subsequently progressed to X-ray crystallography, where a number of exemplars showed significant diversity in their binding modes. The hits identified were supplemented by searching and screening of additional analogues, which enabled the gathering of further X-ray data where the original hits had not produced liganded structures. The fragment hits were optimized using structure-based design, with some transfer of information between series, which enabled the identification of ligand efficient lead molecules with micromolar levels of inhibition, cellular activity, and good solubility.

MeSH terms

  • Adipocytes / drug effects
  • Adipocytes / enzymology
  • Crystallography, X-Ray
  • High-Throughput Screening Assays
  • Humans
  • Magnetic Resonance Spectroscopy
  • Mitochondria / enzymology*
  • Models, Molecular
  • Peptide Fragments / chemistry
  • Peptide Fragments / pharmacology
  • Protein Binding
  • Structure-Activity Relationship
  • Transaminases / antagonists & inhibitors*


  • Peptide Fragments
  • Transaminases