Bacterial type IV secretion: conjugation systems adapted to deliver effector molecules to host cells

Trends Microbiol. 2000 Aug;8(8):354-60. doi: 10.1016/s0966-842x(00)01792-3.


Several bacterial pathogens utilize conjugation machines to export effector molecules during infection. Such systems are members of the type IV or 'adapted conjugation' secretion family. The prototypical type IV system is the Agrobacterium tumefaciens T-DNA transfer machine, which delivers oncogenic nucleoprotein particles to plant cells. Other pathogens, including Bordetella pertussis, Legionella pneumophila, Brucellaspp. and Helicobacter pylori, use type IV machines to export effector proteins to the extracellular milieu or the mammalian cell cytosol.

Publication types

  • Research Support, U.S. Gov't, P.H.S.
  • Review

MeSH terms

  • Agrobacterium tumefaciens / metabolism
  • Animals
  • Bacterial Proteins / metabolism*
  • Biological Transport
  • Conjugation, Genetic
  • DNA, Bacterial / genetics
  • DNA, Bacterial / metabolism*
  • DNA, Single-Stranded / genetics
  • DNA, Single-Stranded / metabolism*
  • Gram-Negative Bacteria / metabolism*
  • Gram-Negative Bacteria / pathogenicity
  • Virulence


  • Bacterial Proteins
  • DNA, Bacterial
  • DNA, Single-Stranded
  • T-DNA