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Microbial population dynamics and evolutionary outcomes under extreme energy limitation.

ABSTRACT: Microorganisms commonly inhabit energy-limited ecosystems where cellular maintenance and reproduction is highly constrained. To gain insight into how individuals persist under such conditions, we derived demographic parameters from a collection of 21 heterotrophic bacterial taxa by censusing 100 populations in an effectively closed system for 1,000 d. All but one taxon survived prolonged resource scarcity, yielding estimated times to extinction ranging over four orders of magnitude from 10⁰ to 10⁵ y. Our findings corroborate reports of long-lived bacteria recovered from ancient environmental samples, while providing insight into mechanisms of persistence. As death rates declined over time, lifespan was extended through the scavenging of dead cells. Although reproduction was suppressed in the absence of exogenous resources, populations continued to evolve. Hundreds of mutations were acquired, contributing to genome-wide signatures of purifying selection as well as molecular signals of adaptation. Consistent ecological and evolutionary dynamics indicate that distantly related bacteria respond to energy limitation in a similar and predictable manner, which likely contributes to the stability and robustness of microbial life.

SUBMITTER: Shoemaker WR

PROVIDER: S-EPMC8379937 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature

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Microbial population dynamics and evolutionary outcomes under extreme energy limitation.

Shoemaker William R WR Jones Stuart E SE Muscarella Mario E ME Behringer Megan G MG Lehmkuhl Brent K BK Lennon Jay T JT

Proceedings of the National Academy of Sciences of the United States of America 20210801 33

Microorganisms commonly inhabit energy-limited ecosystems where cellular maintenance and reproduction is highly constrained. To gain insight into how individuals persist under such conditions, we derived demographic parameters from a collection of 21 heterotrophic bacterial taxa by censusing 100 populations in an effectively closed system for 1,000 d. All but one taxon survived prolonged resource scarcity, yielding estimated times to extinction ranging over four orders of magnitude from 10<sup>0 ...[more]

PMID: 34385301

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Dataset Information

Microbial population dynamics and evolutionary outcomes under extreme energy limitation.

Publications

Microbial population dynamics and evolutionary outcomes under extreme energy limitation.

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