Fucosylated inhibitors of recently identified bangle lectin from Photorhabdus asymbiotica

Sci Rep. 2019 Oct 17;9(1):14904. doi: 10.1038/s41598-019-51357-9.

Abstract

A recently described bangle lectin (PHL) from the bacterium Photorhabdus asymbiotica was identified as a mainly fucose-binding protein that could play an important role in the host-pathogen interaction and in the modulation of host immune response. Structural studies showed that PHL is a homo-dimer that contains up to seven L-fucose-specific binding sites per monomer. For these reasons, potential ligands of the PHL lectin: α-L-fucopyranosyl-containing mono-, di-, tetra-, hexa- and dodecavalent ligands were tested. Two types of polyvalent structures were investigated - calix[4]arenes and dendrimers. The shared feature of all these structures was a C-glycosidic bond instead of the more common but physiologically unstable O-glycosidic bond. The inhibition potential of the tested structures was assessed using different techniques - hemagglutination, surface plasmon resonance, isothermal titration calorimetry, and cell cross-linking. All the ligands proved to be better than free L-fucose. The most active hexavalent dendrimer exhibited affinity three orders of magnitude higher than that of standard L-fucose. To determine the binding mode of some ligands, crystal complex PHL/fucosides 2 - 4 were prepared and studied using X-ray crystallography. The electron density in complexes proved the presence of the compounds in 6 out of 7 fucose-binding sites.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / chemistry
  • Anti-Bacterial Agents / pharmacology*
  • Anti-Bacterial Agents / therapeutic use
  • Bacterial Infections / drug therapy*
  • Bacterial Infections / microbiology
  • Bacterial Proteins / antagonists & inhibitors*
  • Bacterial Proteins / chemistry
  • Bacterial Proteins / isolation & purification
  • Bacterial Proteins / metabolism
  • Binding Sites
  • Crystallography, X-Ray
  • Dendrimers / chemistry
  • Dendrimers / pharmacology
  • Dendrimers / therapeutic use
  • Erythrocytes
  • Fucose / analogs & derivatives
  • Fucose / pharmacology
  • Fucose / therapeutic use
  • Hemagglutination / drug effects
  • Host-Pathogen Interactions / drug effects
  • Humans
  • Lectins / antagonists & inhibitors*
  • Lectins / chemistry
  • Lectins / isolation & purification
  • Lectins / metabolism
  • Ligands
  • Models, Molecular
  • Photorhabdus / metabolism*
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / isolation & purification
  • Recombinant Proteins / metabolism
  • Surface Plasmon Resonance

Substances

  • Anti-Bacterial Agents
  • Bacterial Proteins
  • Dendrimers
  • Lectins
  • Ligands
  • Recombinant Proteins
  • fucose-binding lectin
  • Fucose

Supplementary concepts

  • Photorhabdus asymbiotica