Identification of novel host interactors of effectors secreted by Salmonella and Citrobacter

Ryan L. Sontag, Ernesto S. Nakayasu, Roslyn N. Brown, George S. Niemann, Michael A. Sydor, Octavio Sanchez, Charles Ansong, Shao Yeh Lu, Hyungwon Choi, Dylan Valleau, Karl K. Weitz, Alexei Savchenko, Eric Cambronne, Joshua N. Adkins

5 Scopus citations

Abstract

Many pathogenic bacteria of the family Enterobacteriaceae use type III secretion systems to inject virulence proteins, termed "effectors," into the host cell cytosol. Although host-cellular activities of several effectors have been demonstrated, the function and host-targeted pathways of most of the effectors identified to date are largely undetermined. To gain insight into host proteins targeted by bacterial effectors, we performed coaffinity purification of host proteins from cell lysates using recombinant effectors from the Enterobacteriaceae intracellular pathogens Salmonella enterica serovar Typhimurium and Citrobacter rodentium. We identified 54 high-confidence host interactors for the Salmonella effectors GogA, GtgA, GtgE, SpvC, SrfH, SseL, SspH1, and SssB collectively and 21 interactors for the Citrobacter effectors EspT, NleA, NleG1, and NleK. We biochemically validated the interaction between the SrfH Salmonella protein and the extracellular signal-regulated kinase 2 (ERK2) host protein kinase, which revealed a role for this effector in regulating phosphorylation levels of this enzyme, which plays a central role in signal transduction.

Original languageEnglish (US)
Article numbere00032
JournalmSystems
Volume1
Issue number4
DOIs
Publication statusPublished - Jul 1 2016

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Keywords

  • Affinity purification
  • Effectors
  • Mass spectrometry
  • Pathogenic bacteria
  • Protein-protein interactions
  • Type III secretion system

ASJC Scopus subject areas

  • Molecular Biology
  • Physiology
  • Genetics
  • Biochemistry
  • Modeling and Simulation
  • Computer Science Applications
  • Ecology, Evolution, Behavior and Systematics
  • Microbiology

Cite this

Sontag, R. L., Nakayasu, E. S., Brown, R. N., Niemann, G. S., Sydor, M. A., Sanchez, O., ... Adkins, J. N. (2016). Identification of novel host interactors of effectors secreted by Salmonella and Citrobacter. mSystems, 1(4), [e00032]. https://doi.org/10.1128/mSystems.00032-15