Title: Stochastic Variation in Expression of the Tricarboxylic Acid Cycle Produces Persister Cells

Abstract

Chronic bacterial infections are difficult to eradicate, though they are caused primarily by drug-susceptible pathogens. Antibiotic-tolerant persisters largely account for this paradox. In spite of their significance in the recalcitrance of chronic infections, the mechanism of persister formation is poorly understood. We previously reported that a decrease in ATP levels leads to drug tolerance inEscherichia coli,Pseudomonas aeruginosa, andStaphylococcus aureus. We reasoned that stochastic fluctuation in the expression of tricarboxylic acid (TCA) cycle enzymes can produce cells with low energy levels.S. aureusknockouts in glutamate dehydrogenase, 2-oxoketoglutarate dehydrogenase, succinyl coenzyme A (CoA) synthetase, and fumarase have low ATP levels and exhibit increased tolerance of fluoroquinolone, aminoglycoside, and β-lactam antibiotics. Fluorescence-activated cell sorter (FACS) analysis of TCA genes shows a broad Gaussian distribution in a population, with differences of over 3 orders of magnitude in the levels of expression between individual cells. Sorted cells with low levels of TCA enzyme expression have an increased tolerance of antibiotic treatment. Here, these findings suggest that fluctuations in the levels of expression of energy-generating components serve as a mechanism of persister formation. Persister cells are rare phenotypic variants that are able to survive antibiotic treatment. Unlike resistant bacteria, which have specific mechanisms to prevent antibiotics frommore » binding to their targets, persisters evade antibiotic killing by entering a tolerant nongrowing state. Persisters have been implicated in chronic infections in multiple species, and growing evidence suggests that persister cells are responsible for many cases of antibiotic treatment failure. New antibiotic treatment strategies aim to kill tolerant persister cells more effectively, but the mechanism of tolerance has remained unclear until now.« less

Authors:

Zalis, Eliza A. ^[1]; Nuxoll, Austin S. ^[2]; Manuse, Sylvie ^[1]; Clair, Geremy  ^[3];

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• Search DOE PAGES for ORCID "0000-0003-0478-8520"
• Search orcid.org for ORCID "0000-0003-0478-8520"

Radlinski, Lauren C. ^[4]; Conlon, Brian P. ^[4]; Adkins, Joshua N.  ^[3];

• Search DOE PAGES for author "Adkins, Joshua N."
• Search DOE PAGES for ORCID "0000-0003-0399-0700"
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Lewis, Kim  ^[1]

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• Search DOE PAGES for ORCID "0000-0002-1335-9982"
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+ Show Author Affiliations

1. Northeastern Univ., Boston, MA (United States)
2. Northeastern Univ., Boston, MA (United States); Univ. of Nebraska at Kearney, Kearney, NE (United States)
3. Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
4. North Carolina School of Medicine, Chapel Hill, NC (United States)

Publication Date:

2019-09-17

Research Org.:

Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

Sponsoring Org.:

USDOE

OSTI Identifier:

1573351

Report Number(s):

PNNL-SA-147078
Journal ID: ISSN 2150-7511

Grant/Contract Number:  

AC05-76RL01830

Resource Type:

Accepted Manuscript

Journal Name:

mBio (Online)

Additional Journal Information:

Journal Name: mBio (Online); Journal Volume: 10; Journal Issue: 5; Journal ID: ISSN 2150-7511

Publisher:

American Society for Microbiology

Country of Publication:

United States

Language:

English

Subject:

59 BASIC BIOLOGICAL SCIENCES