Rab1-AMPylation by Legionella DrrA is allosterically activated by Rab1

Nat Commun. 2021 Jan 19;12(1):460. doi: 10.1038/s41467-020-20702-2.

Abstract

Legionella pneumophila infects eukaryotic cells by forming a replicative organelle - the Legionella containing vacuole. During this process, the bacterial protein DrrA/SidM is secreted and manipulates the activity and post-translational modification (PTM) states of the vesicular trafficking regulator Rab1. As a result, Rab1 is modified with an adenosine monophosphate (AMP), and this process is referred to as AMPylation. Here, we use a chemical approach to stabilise low-affinity Rab:DrrA complexes in a site-specific manner to gain insight into the molecular basis of the interaction between the Rab protein and the AMPylation domain of DrrA. The crystal structure of the Rab:DrrA complex reveals a previously unknown non-conventional Rab-binding site (NC-RBS). Biochemical characterisation demonstrates allosteric stimulation of the AMPylation activity of DrrA via Rab binding to the NC-RBS. We speculate that allosteric control of DrrA could in principle prevent random and potentially cytotoxic AMPylation in the host, thereby perhaps ensuring efficient infection by Legionella.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Monophosphate / metabolism*
  • Allosteric Regulation
  • Bacterial Proteins / genetics
  • Bacterial Proteins / isolation & purification
  • Bacterial Proteins / metabolism*
  • Bacterial Proteins / ultrastructure
  • Binding Sites / genetics
  • Crystallography, X-Ray
  • Guanine Nucleotide Exchange Factors / genetics
  • Guanine Nucleotide Exchange Factors / isolation & purification
  • Guanine Nucleotide Exchange Factors / metabolism*
  • Guanine Nucleotide Exchange Factors / ultrastructure
  • Guanosine Triphosphate / metabolism
  • Humans
  • Legionella pneumophila / metabolism
  • Legionella pneumophila / pathogenicity*
  • Legionnaires' Disease / microbiology
  • Legionnaires' Disease / pathology*
  • Macrophages, Alveolar / metabolism
  • Macrophages, Alveolar / microbiology
  • Phagocytosis
  • Protein Binding
  • Protein Processing, Post-Translational
  • Recombinant Proteins / genetics
  • Recombinant Proteins / isolation & purification
  • Recombinant Proteins / metabolism
  • Recombinant Proteins / ultrastructure
  • rab1 GTP-Binding Proteins / genetics
  • rab1 GTP-Binding Proteins / isolation & purification
  • rab1 GTP-Binding Proteins / metabolism*
  • rab1 GTP-Binding Proteins / ultrastructure

Substances

  • Bacterial Proteins
  • Guanine Nucleotide Exchange Factors
  • Recombinant Proteins
  • SidM protein, Legionella pneumophila
  • Adenosine Monophosphate
  • Guanosine Triphosphate
  • Rab1B protein, human
  • rab1 GTP-Binding Proteins