The phenotypic evolution of pseudomonas aeruginosa populations changes in the presence of subinhibitory concentrations of ciprofloxacin

Tina Wassermann; Karin Meinike Jørgensen; Karolina Ivanyshyn; Thomas Bjarnsholt; S. M. Hossein Khademi; Lars Jelsbak; Niels Høiby; Oana Ciofu

doi:10.1099/mic.0.000273

The phenotypic evolution of pseudomonas aeruginosa populations changes in the presence of subinhibitory concentrations of ciprofloxacin

Tina Wassermann, Karin Meinike Jørgensen, Karolina Ivanyshyn, Thomas Bjarnsholt, S. M. Hossein Khademi, Lars Jelsbak, Niels Høiby, Oana Ciofu^*

^*Corresponding author for this work

14 Citations (Scopus)

Abstract

Ciprofloxacin is a widely used antibiotic, in the class of quinolones, for treatment of Pseudomonas aeruginosa infections. The immediate response of P. aeruginosa to subinhibitory concentrations of ciprofloxacin has been investigated previously. However, the long-term phenotypic adaptation, which identifies the fitted phenotypes that have been selected during evolution with subinhibitory concentrations of ciprofloxacin, has not been studied. We chose an experimental evolution approach to investigate how exposure to subinhibitory concentrations of ciprofloxacin changes the evolution of P. aeruginosa populations compared to unexposed populations. Three replicate populations of P. aeruginosa PAO1 and its hypermutable mutant ΔmutS were cultured aerobically for approximately 940 generations by daily passages in LB medium with and without subinhibitory concentration of ciprofloxacin and aliquots of the bacterial populations were regularly sampled and kept at 280 °C for further investigations. We investigate here phenotypic changes between the ancestor (50 colonies) and evolved populations (120 colonies/strain). Decreased protease activity and swimming motility, higher levels of quorum-sensing signal molecules and occurrence of mutator subpopulations were observed in the ciprofloxacin-exposed populations compared to the ancestor and control populations. Transcriptomic analysis showed downregulation of the type III secretion system in evolved populations compared to the ancestor population and upregulation of denitrification genes in ciprofloxacin-evolved populations. In conclusion, the presence of antibiotics at subinhibitory concentration in the environment affects bacterial evolution and further studies are needed to obtain insight into the dynamics of the phenotypes and the mechanisms involved.

Original language	English
Journal	Microbiology
Volume	162
Issue number	5
Pages (from-to)	865-875
Number of pages	11
ISSN	1350-0872
DOIs	https://doi.org/10.1099/mic.0.000273
Publication status	Published - 1 May 2016

Access to Document

10.1099/mic.0.000273

Cite this

@article{09af28c2d4704a699e10ecdb0e55315b,

title = "The phenotypic evolution of pseudomonas aeruginosa populations changes in the presence of subinhibitory concentrations of ciprofloxacin",

abstract = "Ciprofloxacin is a widely used antibiotic, in the class of quinolones, for treatment of Pseudomonas aeruginosa infections. The immediate response of P. aeruginosa to subinhibitory concentrations of ciprofloxacin has been investigated previously. However, the long-term phenotypic adaptation, which identifies the fitted phenotypes that have been selected during evolution with subinhibitory concentrations of ciprofloxacin, has not been studied. We chose an experimental evolution approach to investigate how exposure to subinhibitory concentrations of ciprofloxacin changes the evolution of P. aeruginosa populations compared to unexposed populations. Three replicate populations of P. aeruginosa PAO1 and its hypermutable mutant ΔmutS were cultured aerobically for approximately 940 generations by daily passages in LB medium with and without subinhibitory concentration of ciprofloxacin and aliquots of the bacterial populations were regularly sampled and kept at 280 °C for further investigations. We investigate here phenotypic changes between the ancestor (50 colonies) and evolved populations (120 colonies/strain). Decreased protease activity and swimming motility, higher levels of quorum-sensing signal molecules and occurrence of mutator subpopulations were observed in the ciprofloxacin-exposed populations compared to the ancestor and control populations. Transcriptomic analysis showed downregulation of the type III secretion system in evolved populations compared to the ancestor population and upregulation of denitrification genes in ciprofloxacin-evolved populations. In conclusion, the presence of antibiotics at subinhibitory concentration in the environment affects bacterial evolution and further studies are needed to obtain insight into the dynamics of the phenotypes and the mechanisms involved.",

author = "Tina Wassermann and J{\o}rgensen, {Karin Meinike} and Karolina Ivanyshyn and Thomas Bjarnsholt and {Hossein Khademi}, {S. M.} and Lars Jelsbak and Niels H{\o}iby and Oana Ciofu",

year = "2016",

month = may,

day = "1",

doi = "10.1099/mic.0.000273",

language = "English",

volume = "162",

pages = "865--875",

journal = "Microbiology",

issn = "1350-0872",

publisher = "Society for General Microbiology",

number = "5",

}

TY - JOUR

T1 - The phenotypic evolution of pseudomonas aeruginosa populations changes in the presence of subinhibitory concentrations of ciprofloxacin

AU - Wassermann, Tina

AU - Jørgensen, Karin Meinike

AU - Ivanyshyn, Karolina

AU - Bjarnsholt, Thomas

AU - Hossein Khademi, S. M.

AU - Jelsbak, Lars

AU - Høiby, Niels

AU - Ciofu, Oana

PY - 2016/5/1

Y1 - 2016/5/1

N2 - Ciprofloxacin is a widely used antibiotic, in the class of quinolones, for treatment of Pseudomonas aeruginosa infections. The immediate response of P. aeruginosa to subinhibitory concentrations of ciprofloxacin has been investigated previously. However, the long-term phenotypic adaptation, which identifies the fitted phenotypes that have been selected during evolution with subinhibitory concentrations of ciprofloxacin, has not been studied. We chose an experimental evolution approach to investigate how exposure to subinhibitory concentrations of ciprofloxacin changes the evolution of P. aeruginosa populations compared to unexposed populations. Three replicate populations of P. aeruginosa PAO1 and its hypermutable mutant ΔmutS were cultured aerobically for approximately 940 generations by daily passages in LB medium with and without subinhibitory concentration of ciprofloxacin and aliquots of the bacterial populations were regularly sampled and kept at 280 °C for further investigations. We investigate here phenotypic changes between the ancestor (50 colonies) and evolved populations (120 colonies/strain). Decreased protease activity and swimming motility, higher levels of quorum-sensing signal molecules and occurrence of mutator subpopulations were observed in the ciprofloxacin-exposed populations compared to the ancestor and control populations. Transcriptomic analysis showed downregulation of the type III secretion system in evolved populations compared to the ancestor population and upregulation of denitrification genes in ciprofloxacin-evolved populations. In conclusion, the presence of antibiotics at subinhibitory concentration in the environment affects bacterial evolution and further studies are needed to obtain insight into the dynamics of the phenotypes and the mechanisms involved.

AB - Ciprofloxacin is a widely used antibiotic, in the class of quinolones, for treatment of Pseudomonas aeruginosa infections. The immediate response of P. aeruginosa to subinhibitory concentrations of ciprofloxacin has been investigated previously. However, the long-term phenotypic adaptation, which identifies the fitted phenotypes that have been selected during evolution with subinhibitory concentrations of ciprofloxacin, has not been studied. We chose an experimental evolution approach to investigate how exposure to subinhibitory concentrations of ciprofloxacin changes the evolution of P. aeruginosa populations compared to unexposed populations. Three replicate populations of P. aeruginosa PAO1 and its hypermutable mutant ΔmutS were cultured aerobically for approximately 940 generations by daily passages in LB medium with and without subinhibitory concentration of ciprofloxacin and aliquots of the bacterial populations were regularly sampled and kept at 280 °C for further investigations. We investigate here phenotypic changes between the ancestor (50 colonies) and evolved populations (120 colonies/strain). Decreased protease activity and swimming motility, higher levels of quorum-sensing signal molecules and occurrence of mutator subpopulations were observed in the ciprofloxacin-exposed populations compared to the ancestor and control populations. Transcriptomic analysis showed downregulation of the type III secretion system in evolved populations compared to the ancestor population and upregulation of denitrification genes in ciprofloxacin-evolved populations. In conclusion, the presence of antibiotics at subinhibitory concentration in the environment affects bacterial evolution and further studies are needed to obtain insight into the dynamics of the phenotypes and the mechanisms involved.

U2 - 10.1099/mic.0.000273

DO - 10.1099/mic.0.000273

M3 - Journal article

C2 - 26953154

AN - SCOPUS:84964933310

SN - 1350-0872

VL - 162

SP - 865

EP - 875

JO - Microbiology

JF - Microbiology

IS - 5

ER -

The phenotypic evolution of pseudomonas aeruginosa populations changes in the presence of subinhibitory concentrations of ciprofloxacin

Abstract

Access to Document

Fingerprint

Cite this