A high-resolution data set of fatty acid-binding protein structures. III. Unexpectedly high occurrence of wrong ligands

Acta Crystallogr D Struct Biol. 2025 Aug 1;81(Pt 8):451-464. doi: 10.1107/S2059798325006096. Epub 2025 Jul 28.

Abstract

FABP4 has been implicated as a therapeutic target for treating diabetes and atherosclerosis. Structure-based drug design (SBDD) based on initial hits from high-throughput and fragment screens yielded 216 ligand-bound structures of human FABP3, FABP4 and FABP5 isoforms, many of which were at resolutions of better than 1.2 Å. An estimated 15% of the ligands had a different chemical composition to that expected from the starting materials or the final synthesis product, highlighting a potential problem inherent to all SBDD campaigns conducted at lower resolution. Apart from possible human error during compound registration, side reactions such as additions, eliminations, isomerizations, cyclizations and dimerizations were found that led to compounds capable of binding to FABP.

Keywords: fatty acid-binding proteins; ligand binding; structure-based drug design; unexpected chemical composition.

MeSH terms

  • Binding Sites
  • Crystallography, X-Ray
  • Drug Design
  • Fatty Acid Binding Protein 3 / chemistry
  • Fatty Acid-Binding Proteins* / chemistry
  • Fatty Acid-Binding Proteins* / metabolism
  • Humans
  • Ligands
  • Models, Molecular
  • Protein Binding
  • Protein Conformation

Substances

  • Ligands
  • Fatty Acid-Binding Proteins
  • FABP4 protein, human
  • Fatty Acid Binding Protein 3
  • FABP3 protein, human
  • FABP5 protein, human