Legionella pneumophila, armed to the hilt: justifying the largest arsenal of effectors in the bacterial world

Curr Opin Microbiol. 2016 Feb;29:74-80. doi: 10.1016/j.mib.2015.11.002. Epub 2015 Dec 19.


Many bacterial pathogens use dedicated translocation systems to deliver arsenals of effector proteins to their hosts. Once inside the host cytosol, these effectors modulate eukaryotic cell biology to acquire nutrients, block microbial degradation, subvert host defenses, and enable pathogen transmission to other hosts. Among all bacterial pathogens studied to date, the gram-negative pathogen, Legionella pneumophila, maintains the largest arsenal of effectors, with over 330 effector proteins translocated by the Dot/Icm type IVB translocation system. In this review, I will discuss some of the recent work on understanding the consequences of this large arsenal. I will also present several models that seek to explain how L. pneumophila has acquired and subsequently maintained so many more effectors than its peers.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Bacterial Proteins / metabolism*
  • Bacterial Secretion Systems / physiology*
  • Carrier Proteins / metabolism
  • Cytosol / microbiology
  • Genome, Bacterial
  • Host-Pathogen Interactions / physiology
  • Legionella pneumophila / metabolism
  • Legionella pneumophila / pathogenicity*
  • Legionnaires' Disease / microbiology*
  • Membrane Proteins / metabolism
  • Models, Biological
  • Protein Transport


  • Bacterial Proteins
  • Bacterial Secretion Systems
  • Carrier Proteins
  • Membrane Proteins