Nature Reviews Microbiology 10, 472-482 (July 2012) | doi:10.1038/nrmicro2802

Gene transfer agents: phage-like elements of genetic exchange

Andrew S. Lang1, Olga Zhaxybayeva2,3,5 & J. Thomas Beatty4  About the authors


Horizontal gene transfer is important in the evolution of bacterial and archaeal genomes. An interesting genetic exchange process is carried out by diverse phage-like gene transfer agents (GTAs) that are found in a wide range of prokaryotes. Although GTAs resemble phages, they lack the hallmark capabilities that define typical phages, and they package random pieces of the producing cell's genome. In this Review, we discuss the defining characteristics of the GTAs that have been identified to date, along with potential functions for these agents and the possible evolutionary forces that act on the genes involved in their production.

Author affiliations

  1. Department of Biology, Memorial University, 232 Elizabeth Avenue, St. John's, Newfoundland and Labrador A1B 3X9, Canada.
  2. Department of Biology, West Virginia University, PO Box 6057, Morgantown, West Virginia 26506, USA.
  3. Department of Biological Sciences, Dartmouth College, 78 College Street, Hanover, New Hampshire 03755, USA.
  4. Department of Microbiology and Immunology, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia V6T 1Z3, Canada.
  5. Present address.
    e-mails: Email:; Email:; Email:

Published online 11 June 2012