Ligand interaction landscape of transcription factors and essential enzymes in E. coli

Cell. 2025 Mar 6;188(5):1441-1455.e15. doi: 10.1016/j.cell.2025.01.003. Epub 2025 Jan 24.

Abstract

Knowledge of protein-metabolite interactions can enhance mechanistic understanding and chemical probing of biochemical processes, but the discovery of endogenous ligands remains challenging. Here, we combined rapid affinity purification with precision mass spectrometry and high-resolution molecular docking to precisely map the physical associations of 296 chemically diverse small-molecule metabolite ligands with 69 distinct essential enzymes and 45 transcription factors in the gram-negative bacterium Escherichia coli. We then conducted systematic metabolic pathway integration, pan-microbial evolutionary projections, and independent in-depth biophysical characterization experiments to define the functional significance of ligand interfaces. This effort revealed principles governing functional crosstalk on a network level, divergent patterns of binding pocket conservation, and scaffolds for designing selective chemical probes. This structurally resolved ligand interactome mapping pipeline can be scaled to illuminate the native small-molecule networks of complete cells and potentially entire multi-cellular communities.

Keywords: LP/MS; chemical probe; dynamic network; enzymes; molecular docking; multi-modal interactome; precision structural modeling; protein-ligand binding pocket; protein-metabolite interactions; transcription factors.

MeSH terms

  • Binding Sites
  • Escherichia coli Proteins* / chemistry
  • Escherichia coli Proteins* / metabolism
  • Escherichia coli* / enzymology
  • Escherichia coli* / metabolism
  • Ligands
  • Metabolic Networks and Pathways
  • Molecular Docking Simulation
  • Protein Binding
  • Transcription Factors* / chemistry
  • Transcription Factors* / metabolism

Substances

  • Ligands
  • Transcription Factors
  • Escherichia coli Proteins