Mimivirus Inaugurated in the 21st Century the Beginning of a Reclassification of Viruses

Curr Opin Microbiol. 2016 Jun;31:16-24. doi: 10.1016/j.mib.2015.12.010. Epub 2016 Jan 30.


Mimivirus and other giant viruses are visible by light microscopy and bona fide microbes that differ from other viruses and from cells that have a ribosome. They can be defined by: giant virion and genome sizes; their complexity, with the presence of DNA and mRNAs and dozens or hundreds of proteins in virions; the presence of translation-associated components; a mobilome including (pro)virophages (and a defence mechanism, named MIMIVIRE, against them) and transpovirons; their monophyly; the presence of the most archaic protein motifs they share with cellular organisms but not other viruses; a broader host range than other viruses. These features show that giant viruses are specific, autonomous, biological entities that warrant the creation of a new branch of microbes.

Publication types

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

MeSH terms

  • Acanthamoeba / virology
  • Biological Evolution
  • DNA, Viral / genetics
  • Genome, Viral / genetics*
  • Giant Viruses / classification*
  • Giant Viruses / genetics*
  • Mimiviridae / classification*
  • Mimiviridae / genetics*


  • DNA, Viral