Targeting a Multidrug-Resistant Pathogen: First Generation Antagonists of Burkholderia cenocepacia's BC2L-C Lectin

ACS Chem Biol. 2022 Oct 21;17(10):2899-2910. doi: 10.1021/acschembio.2c00532. Epub 2022 Sep 29.

Abstract

Multidrug-resistant pathogens such as Burkholderia cenocepacia have become a hazard in the context of healthcare-associated infections, especially for patients admitted with cystic fibrosis or immuno-compromising conditions. Like other opportunistic Gram-negative bacteria, this pathogen establishes virulence and biofilms through lectin-mediated adhesion. In particular, the superlectin BC2L-C is believed to cross-link human epithelial cells to B. cenocepacia during pulmonary infections. We aimed to obtain glycomimetic antagonists able to inhibit the interaction between the N-terminal domain of BC2L-C (BC2L-C-Nt) and its target fucosylated human oligosaccharides. In a previous study, we identified by fragment virtual screening and validated a small set of molecular fragments that bind BC2L-C-Nt in the vicinity of the fucose binding site. Here, we report the rational design and synthesis of bifunctional C- or N-fucosides, generated by connecting these fragments to a fucoside core using a panel of rationally selected linkers. A modular route starting from two key fucoside intermediates was implemented for the synthesis, followed by evaluation of the new compounds as BC2L-C-Nt ligands with a range of techniques (surface plasmon resonance, isothermal titration calorimetry, saturation transfer difference NMR, differential scanning calorimetry, and X-ray crystallography). This study resulted in a hit molecule with an order of magnitude gain over the starting methyl fucoside and in two crystal structures of antagonist/lectin complexes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Burkholderia cenocepacia* / chemistry
  • Burkholderia cenocepacia* / metabolism
  • Burkholderia* / chemistry
  • Fucose / chemistry
  • Humans
  • Lectins / chemistry
  • Models, Molecular
  • Oligosaccharides / chemistry

Substances

  • Lectins
  • Fucose
  • Oligosaccharides