Inter-species population dynamics enhance microbial horizontal gene transfer and spread of antibiotic resistance

  1. Robert M Cooper  Is a corresponding author
  2. Lev Tsimring
  3. Jeff Hasty  Is a corresponding author
  1. University of California, San Diego, United States

Abstract

Horizontal gene transfer (HGT) plays a major role in the spread of antibiotic resistance. Of particular concern are Acinetobacter baumannii bacteria, which recently emerged as global pathogens, with nosocomial mortality rates reaching 19-54%. Acinetobacter gains antibiotic resistance remarkably rapidly, with multi drug-resistance (MDR) rates exceeding 60%. Despite growing concern, the mechanisms underlying this extensive HGT remain poorly understood. Here, we show bacterial predation by Acinetobacter baylyi increases cross-species HGT by orders of magnitude, and we observe predator cells functionally acquiring adaptive resistance genes from adjacent prey. We then develop a population-dynamic model quantifying killing and HGT on solid surfaces. We show DNA released via cell lysis is readily available for HGT and may be partially protected from the environment, describe the effects of cell density, and evaluate potential environmental inhibitors. These findings establish a framework for understanding, quantifying, and combating HGT within the microbiome and the emergence of MDR super-bugs.

Article and author information

Author details

  1. Robert M Cooper

    BioCircuits Institute, University of California, San Diego, La Jolla, United States
    For correspondence
    robmcooper@gmail.com
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2136-0403
  2. Lev Tsimring

    BioCircuits Institute, University of California, San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Jeff Hasty

    BioCircuits Institute, University of California, San Diego, La Jolla, United States
    For correspondence
    jhasty@eng.ucsd.edu
    Competing interests
    The authors declare that no competing interests exist.

Funding

Hartwell Foundation

  • Robert M Cooper

National Institute of General Medical Sciences (San Diego Center for Systems Biology - P50 GM085764)

  • Robert M Cooper
  • Lev Tsimring
  • Jeff Hasty

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Ben Cooper, Mahidol Oxford Tropical Medicine Research Unit, Thailand

Version history

  1. Received: February 11, 2017
  2. Accepted: October 10, 2017
  3. Accepted Manuscript published: November 1, 2017 (version 1)
  4. Version of Record published: November 17, 2017 (version 2)

Copyright

© 2017, Cooper et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Robert M Cooper
  2. Lev Tsimring
  3. Jeff Hasty
(2017)
Inter-species population dynamics enhance microbial horizontal gene transfer and spread of antibiotic resistance
eLife 6:e25950.
https://doi.org/10.7554/eLife.25950

Share this article

https://doi.org/10.7554/eLife.25950

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