Extreme genome reduction in symbiotic bacteria

@article{McCutcheon2012ExtremeGR,
  title={Extreme genome reduction in symbiotic bacteria},
  author={John P. McCutcheon and Nancy A. Moran},
  journal={Nature Reviews Microbiology},
  year={2012},
  volume={10},
  pages={13-26}
}
Since 2006, numerous cases of bacterial symbionts with extraordinarily small genomes have been reported. These organisms represent independent lineages from diverse bacterial groups. They have diminutive gene sets that rival some mitochondria and chloroplasts in terms of gene numbers and lack genes that are considered to be essential in other bacteria. These symbionts have numerous features in common, such as extraordinarily fast protein evolution and a high abundance of chaperones. Together… 
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