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Factors driving effective population size and pan-genome evolution in bacteria.

ABSTRACT: BACKGROUND:Knowledge of population-level processes is essential to understanding the efficacy of selection operating within a species. However, attempts at estimating effective population sizes (Ne) are particularly challenging in bacteria due to their extremely large census populations sizes, varying rates of recombination and arbitrary species boundaries. RESULTS:In this study, we estimated Ne for 153 species (152 bacteria and one archaeon) defined under a common framework and found that ecological lifestyle and growth rate were major predictors of Ne; and that contrary to theoretical expectations, Ne was unaffected by recombination rate. Additionally, we found that Ne shapes the evolution and diversity of total gene repertoires of prokaryotic species. CONCLUSION:Together, these results point to a new model of genome architecture evolution in prokaryotes, in which pan-genome sizes, not individual genome sizes, are governed by drift-barrier evolution.

SUBMITTER: Bobay LM

PROVIDER: S-EPMC6186134 | biostudies-other | 2018 Oct

REPOSITORIES: biostudies-other

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Factors driving effective population size and pan-genome evolution in bacteria.

Bobay Louis-Marie LM Ochman Howard H

BMC evolutionary biology 20181012 1

<h4>Background</h4>Knowledge of population-level processes is essential to understanding the efficacy of selection operating within a species. However, attempts at estimating effective population sizes (Ne) are particularly challenging in bacteria due to their extremely large census populations sizes, varying rates of recombination and arbitrary species boundaries.<h4>Results</h4>In this study, we estimated Ne for 153 species (152 bacteria and one archaeon) defined under a common framework and f ...[more]

PMID: 30314447

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