Pharmacodynamics, population dynamics, and the evolution of persistence in Staphylococcus aureus.

When growing populations of bacteria are confronted with bactericidal antibiotics, the vast majority of cells are killed, but subpopulations of genetically susceptible but phenotypically resistant bacteria survive. In accord with the prevailing view, these "persisters" are non- or slowly d...

Full description

Bibliographic Details
Main Authors: Paul J T Johnson, Bruce R Levin
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2013-01-01
Series:PLoS Genetics
Online Access:http://europepmc.org/articles/PMC3536638?pdf=render
_version_ 1818059083782029312
author Paul J T Johnson
Bruce R Levin
author_facet Paul J T Johnson
Bruce R Levin
author_sort Paul J T Johnson
collection DOAJ
description When growing populations of bacteria are confronted with bactericidal antibiotics, the vast majority of cells are killed, but subpopulations of genetically susceptible but phenotypically resistant bacteria survive. In accord with the prevailing view, these "persisters" are non- or slowly dividing cells randomly generated from the dominant population. Antibiotics enrich populations for pre-existing persisters but play no role in their generation. The results of recent studies with Escherichia coli suggest that at least one antibiotic, ciprofloxacin, can contribute to the generation of persisters. To more generally elucidate the role of antibiotics in the generation of and selection for persisters and the nature of persistence in general, we use mathematical models and experiments with Staphylococcus aureus (Newman) and the antibiotics ciprofloxacin, gentamicin, vancomycin, and oxacillin. Our results indicate that the level of persistence varies among these drugs and their concentrations, and there is considerable variation in this level among independent cultures and mixtures of independent cultures. A model that assumes that the rate of production of persisters is low and persisters grow slowly in the presence of antibiotics can account for these observations. As predicted by this model, pre-treatment with sub-MIC concentrations of antibiotics substantially increases the level of persistence to drugs other than those with which the population is pre-treated. Collectively, the results of this jointly theoretical and experimental study along with other observations support the hypothesis that persistence is the product of many different kinds of errors in cell replication that result in transient periods of non-replication and/or slowed metabolism by individual cells in growing populations. This Persistence as Stuff Happens (PaSH) hypothesis can account for the ubiquity of this phenomenon. Like mutation, persistence is inevitable rather than an evolved character. What evolved and have been identified are genes and processes that affect the frequency of persisters.
first_indexed 2024-12-10T13:10:53Z
format Article
id doaj.art-8209d411f6c7456bb021415164874f17
institution Directory Open Access Journal
issn 1553-7390
1553-7404
language English
last_indexed 2024-12-10T13:10:53Z
publishDate 2013-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS Genetics
spelling doaj.art-8209d411f6c7456bb021415164874f172022-12-22T01:47:41ZengPublic Library of Science (PLoS)PLoS Genetics1553-73901553-74042013-01-0191e100312310.1371/journal.pgen.1003123Pharmacodynamics, population dynamics, and the evolution of persistence in Staphylococcus aureus.Paul J T JohnsonBruce R LevinWhen growing populations of bacteria are confronted with bactericidal antibiotics, the vast majority of cells are killed, but subpopulations of genetically susceptible but phenotypically resistant bacteria survive. In accord with the prevailing view, these "persisters" are non- or slowly dividing cells randomly generated from the dominant population. Antibiotics enrich populations for pre-existing persisters but play no role in their generation. The results of recent studies with Escherichia coli suggest that at least one antibiotic, ciprofloxacin, can contribute to the generation of persisters. To more generally elucidate the role of antibiotics in the generation of and selection for persisters and the nature of persistence in general, we use mathematical models and experiments with Staphylococcus aureus (Newman) and the antibiotics ciprofloxacin, gentamicin, vancomycin, and oxacillin. Our results indicate that the level of persistence varies among these drugs and their concentrations, and there is considerable variation in this level among independent cultures and mixtures of independent cultures. A model that assumes that the rate of production of persisters is low and persisters grow slowly in the presence of antibiotics can account for these observations. As predicted by this model, pre-treatment with sub-MIC concentrations of antibiotics substantially increases the level of persistence to drugs other than those with which the population is pre-treated. Collectively, the results of this jointly theoretical and experimental study along with other observations support the hypothesis that persistence is the product of many different kinds of errors in cell replication that result in transient periods of non-replication and/or slowed metabolism by individual cells in growing populations. This Persistence as Stuff Happens (PaSH) hypothesis can account for the ubiquity of this phenomenon. Like mutation, persistence is inevitable rather than an evolved character. What evolved and have been identified are genes and processes that affect the frequency of persisters.http://europepmc.org/articles/PMC3536638?pdf=render
spellingShingle Paul J T Johnson
Bruce R Levin
Pharmacodynamics, population dynamics, and the evolution of persistence in Staphylococcus aureus.
PLoS Genetics
title Pharmacodynamics, population dynamics, and the evolution of persistence in Staphylococcus aureus.
title_full Pharmacodynamics, population dynamics, and the evolution of persistence in Staphylococcus aureus.
title_fullStr Pharmacodynamics, population dynamics, and the evolution of persistence in Staphylococcus aureus.
title_full_unstemmed Pharmacodynamics, population dynamics, and the evolution of persistence in Staphylococcus aureus.
title_short Pharmacodynamics, population dynamics, and the evolution of persistence in Staphylococcus aureus.
title_sort pharmacodynamics population dynamics and the evolution of persistence in staphylococcus aureus
url http://europepmc.org/articles/PMC3536638?pdf=render
work_keys_str_mv AT pauljtjohnson pharmacodynamicspopulationdynamicsandtheevolutionofpersistenceinstaphylococcusaureus
AT brucerlevin pharmacodynamicspopulationdynamicsandtheevolutionofpersistenceinstaphylococcusaureus