151
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Edelmann D, Oberpaul M, Schäberle TF, Berghoff BA. Post-transcriptional deregulation of the tisB/istR-1 toxin-antitoxin system promotes SOS-independent persister formation in Escherichia coli. ENVIRONMENTAL MICROBIOLOGY REPORTS 2021; 13:159-168. [PMID: 33350069 DOI: 10.1111/1758-2229.12919] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 12/10/2020] [Accepted: 12/11/2020] [Indexed: 06/12/2023]
Abstract
Bacterial dormancy is a valuable strategy to endure unfavourable conditions. The term 'persister' has been coined for cells that tolerate antibiotic treatments due to reduced cellular activity. The type I toxin-antitoxin system tisB/istR-1 is linked to persistence in Escherichia coli, because toxin TisB depolarizes the inner membrane and causes ATP depletion. Transcription of tisB is induced upon activation of the SOS response by DNA-damaging drugs. However, translation is repressed both by a 5' structure within the tisB mRNA and by RNA antitoxin IstR-1. This tight regulation limits TisB production to SOS conditions. Deletion of both regulatory RNA elements produced a 'high persistence' mutant, which was previously assumed to depend on stochastic SOS induction and concomitant TisB production. Here, we demonstrate that the mutant generates a subpopulation of growth-retarded cells during late stationary phase, likely due to SOS-independent TisB accumulation. Cell sorting experiments revealed that the stationary phase-derived subpopulation contains most of the persister cells. Collectively our data show that deletion of the regulatory RNA elements uncouples the persister formation process from the intended stress situation and enables the formation of TisB-dependent persisters in an SOS-independent manner.
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Affiliation(s)
- Daniel Edelmann
- Institute for Microbiology and Molecular Biology, Justus Liebig University Giessen, Giessen, 35392, Germany
| | - Markus Oberpaul
- Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Branch for Bioresources, Giessen, 35392, Germany
| | - Till F Schäberle
- Institute for Insect Biotechnology, Justus Liebig University Giessen, Giessen, 35392, Germany
- Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Branch for Bioresources, Giessen, 35392, Germany
- German Centre for Infection Research (DZIF), Partner Site Giessen-Marburg-Langen, Giessen, 35392, Germany
| | - Bork A Berghoff
- Institute for Microbiology and Molecular Biology, Justus Liebig University Giessen, Giessen, 35392, Germany
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152
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Blaschke U, Skiebe E, Wilharm G. Novel Genes Required for Surface-Associated Motility in Acinetobacter baumannii. Curr Microbiol 2021; 78:1509-1528. [PMID: 33666749 PMCID: PMC7997844 DOI: 10.1007/s00284-021-02407-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 02/10/2021] [Indexed: 01/28/2023]
Abstract
Acinetobacter baumannii is an opportunistic and increasingly multi-drug resistant human pathogen rated as a critical priority one pathogen for the development of new antibiotics by the WHO in 2017. Despite the lack of flagella, A. baumannii can move along wet surfaces in two different ways: via twitching motility and surface-associated motility. While twitching motility is known to depend on type IV pili, the mechanism of surface-associated motility is poorly understood. In this study, we established a library of 30 A. baumannii ATCC® 17978™ mutants that displayed deficiency in surface-associated motility. By making use of natural competence, we also introduced these mutations into strain 29D2 to differentiate strain-specific versus species-specific effects of mutations. Mutated genes were associated with purine/pyrimidine/folate biosynthesis (e.g. purH, purF, purM, purE), alarmone/stress metabolism (e.g. Ap4A hydrolase), RNA modification/regulation (e.g. methionyl-tRNA synthetase), outer membrane proteins (e.g. ompA), and genes involved in natural competence (comEC). All tested mutants originally identified as motility-deficient in strain ATCC® 17978™ also displayed a motility-deficient phenotype in 29D2. By contrast, further comparative characterization of the mutant sets of both strains regarding pellicle biofilm formation, antibiotic resistance, and virulence in the Galleria mellonella infection model revealed numerous strain-specific mutant phenotypes. Our studies highlight the need for comparative analyses to characterize gene functions in A. baumannii and for further studies on the mechanisms underlying surface-associated motility.
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Affiliation(s)
- Ulrike Blaschke
- Robert Koch Institute, Project group P2, Burgstr. 37, 38855, Wernigerode, Germany.
| | - Evelyn Skiebe
- Robert Koch Institute, Project group P2, Burgstr. 37, 38855, Wernigerode, Germany
| | - Gottfried Wilharm
- Robert Koch Institute, Project group P2, Burgstr. 37, 38855, Wernigerode, Germany.
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153
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Sulaiman JE, Lam H. Evolution of Bacterial Tolerance Under Antibiotic Treatment and Its Implications on the Development of Resistance. Front Microbiol 2021; 12:617412. [PMID: 33717007 PMCID: PMC7952611 DOI: 10.3389/fmicb.2021.617412] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 02/12/2021] [Indexed: 01/08/2023] Open
Abstract
Recent laboratory evolution studies have shown that upon repetitive antibiotic treatments, bacterial populations will adapt and eventually became tolerant and resistant to the drug. Drug tolerance rapidly evolves upon frequent, intermittent antibiotic treatments, and such emerging drug tolerance seems to be specific to the treatment conditions, complicating clinical practice. Moreover, it has been shown that tolerance often promotes the development of resistance, which further reinforces the need of clinical diagnostics for antibiotic tolerance to reduce the occurrence of acquired resistance. Here, we discuss the laboratory evolution studies that were performed to track the development of tolerance in bacterial populations, and highlight the urgency of developing a comprehensive knowledge base of various tolerance phenotypes and their detection in clinics. Finally, we propose future directions for basic research in this growing field.
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Affiliation(s)
- Jordy Evan Sulaiman
- Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Kowloon, Hong Kong
| | - Henry Lam
- Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Kowloon, Hong Kong
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154
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Rapacka-Zdonczyk A, Wozniak A, Nakonieczna J, Grinholc M. Development of Antimicrobial Phototreatment Tolerance: Why the Methodology Matters. Int J Mol Sci 2021; 22:2224. [PMID: 33672375 PMCID: PMC7926562 DOI: 10.3390/ijms22042224] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 02/18/2021] [Accepted: 02/19/2021] [Indexed: 12/12/2022] Open
Abstract
Due to rapidly growing antimicrobial resistance, there is an urgent need to develop alternative, non-antibiotic strategies. Recently, numerous light-based approaches, demonstrating killing efficacy regardless of microbial drug resistance, have gained wide attention and are considered some of the most promising antimicrobial modalities. These light-based therapies include five treatments for which high bactericidal activity was demonstrated using numerous in vitro and in vivo studies: antimicrobial blue light (aBL), antimicrobial photodynamic inactivation (aPDI), pulsed light (PL), cold atmospheric plasma (CAP), and ultraviolet (UV) light. Based on their multitarget activity leading to deleterious effects to numerous cell structures-i.e., cell envelopes, proteins, lipids, and genetic material-light-based treatments are considered to have a low risk for the development of tolerance and/or resistance. Nevertheless, the most recent studies indicate that repetitive sublethal phototreatment may provoke tolerance development, but there is no standard methodology for the proper evaluation of this phenomenon. The statement concerning the lack of development of resistance to these modalities seem to be justified; however, the most significant motivation for this review paper was to critically discuss existing dogma concerning the lack of tolerance development, indicating that its assessment is more complex and requires better terminology and methodology.
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Affiliation(s)
- Aleksandra Rapacka-Zdonczyk
- Laboratory of Molecular Diagnostics, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307 Gdansk, Poland; (A.R.-Z.); (A.W.); (J.N.)
- Department of Pharmaceutical Microbiology, The Faculty of Pharmacy, Medical University of Gdansk, Hallera 107, 80-416 Gdansk, Poland
| | - Agata Wozniak
- Laboratory of Molecular Diagnostics, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307 Gdansk, Poland; (A.R.-Z.); (A.W.); (J.N.)
| | - Joanna Nakonieczna
- Laboratory of Molecular Diagnostics, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307 Gdansk, Poland; (A.R.-Z.); (A.W.); (J.N.)
| | - Mariusz Grinholc
- Laboratory of Molecular Diagnostics, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307 Gdansk, Poland; (A.R.-Z.); (A.W.); (J.N.)
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155
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156
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Most-Probable-Number-Based Minimum Duration of Killing Assay for Determining the Spectrum of Rifampicin Susceptibility in Clinical Mycobacterium tuberculosis Isolates. Antimicrob Agents Chemother 2021; 65:AAC.01439-20. [PMID: 33257450 PMCID: PMC8092508 DOI: 10.1128/aac.01439-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 11/24/2020] [Indexed: 12/17/2022] Open
Abstract
Accurate antibiotic susceptibility testing is essential for successful tuberculosis treatment. Recent studies have highlighted the limitations of MIC-based phenotypic susceptibility methods in detecting other aspects of antibiotic susceptibilities in bacteria. Duration and peak of antibiotic exposure, at or above the MIC required for killing the bacterial population, has emerged as another important factor for determining antibiotic susceptibility. This is broadly defined as antibiotic tolerance. Accurate antibiotic susceptibility testing is essential for successful tuberculosis treatment. Recent studies have highlighted the limitations of MIC-based phenotypic susceptibility methods in detecting other aspects of antibiotic susceptibilities in bacteria. Duration and peak of antibiotic exposure, at or above the MIC required for killing the bacterial population, has emerged as another important factor for determining antibiotic susceptibility. This is broadly defined as antibiotic tolerance. Antibiotic tolerance can further facilitate the emergence of antibiotic resistance. Currently, there are limited methods to quantify antibiotic tolerance among clinical M. tuberculosis isolates. In this study, we develop a most-probable-number (MPN)-based minimum duration of killing (MDK) assay to quantify the spectrum of M. tuberculosis rifampicin susceptibility within subpopulations based on the duration of rifampicin exposure required for killing the bacterial population. MDK90–99 and MDK99.99 were defined as the minimum duration of antibiotic exposure at or above the MIC required for killing 90 to 99% and 99.99% of the initial (pretreatment) bacterial population, respectively. Results from the rifampicin MDK assay applied to 28 laboratory and clinical M. tuberculosis isolates showed that there is variation in rifampicin susceptibility among isolates. The rifampicin MDK99/99.99 time for isolates varied from less than 2 to 10 days. MDK was correlated with larger subpopulations of M. tuberculosis from clinical isolates that were rifampicin tolerant. Our study demonstrates the utility of MDK assays to measure the variation in antibiotic tolerance among clinical M. tuberculosis isolates and further expands clinically important aspects of antibiotic susceptibility testing.
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157
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Evolution of Antibiotic Tolerance Shapes Resistance Development in Chronic Pseudomonas aeruginosa Infections. mBio 2021; 12:mBio.03482-20. [PMID: 33563834 PMCID: PMC7885114 DOI: 10.1128/mbio.03482-20] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Over the past decades, pan-resistant strains of major bacterial pathogens have emerged and have rendered clinically available antibiotics ineffective, putting at risk many of the major achievements of modern medicine, including surgery, cancer therapy, and organ transplantation. A thorough understanding of processes leading to the development of antibiotic resistance in human patients is thus urgently needed. The widespread use of antibiotics promotes the evolution and dissemination of resistance and tolerance mechanisms. To assess the relevance of tolerance and its implications for resistance development, we used in vitro evolution and analyzed the inpatient microevolution of Pseudomonas aeruginosa, an important human pathogen causing acute and chronic infections. We show that the development of tolerance precedes and promotes the acquisition of resistance in vitro, and we present evidence that similar processes shape antibiotic exposure in human patients. Our data suggest that during chronic infections, P. aeruginosa first acquires moderate drug tolerance before following distinct evolutionary trajectories that lead to high-level multidrug tolerance or to antibiotic resistance. Our studies propose that the development of antibiotic tolerance predisposes bacteria for the acquisition of resistance at early stages of infection and that both mechanisms independently promote bacterial survival during antibiotic treatment at later stages of chronic infections.
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158
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Himeoka Y, Mitarai N. When to wake up? The optimal waking-up strategies for starvation-induced persistence. PLoS Comput Biol 2021; 17:e1008655. [PMID: 33571191 PMCID: PMC7904209 DOI: 10.1371/journal.pcbi.1008655] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 02/24/2021] [Accepted: 12/21/2020] [Indexed: 11/20/2022] Open
Abstract
Prolonged lag time can be induced by starvation contributing to the antibiotic tolerance of bacteria. We analyze the optimal lag time to survive and grow the iterative and stochastic application of antibiotics. A simple model shows that the optimal lag time can exhibit a discontinuous transition when the severeness of the antibiotic application, such as the probability to be exposed the antibiotic, the death rate under the exposure, and the duration of the exposure, is increased. This suggests the possibility of reducing tolerant bacteria by controlled usage of antibiotics application. When the bacterial populations are able to have two phenotypes with different lag times, the fraction of the second phenotype that has different lag time shows a continuous transition. We then present a generic framework to investigate the optimal lag time distribution for total population fitness for a given distribution of the antibiotic application duration. The obtained optimal distributions have multiple peaks for a wide range of the antibiotic application duration distributions, including the case where the latter is monotonically decreasing. The analysis supports the advantage in evolving multiple, possibly discrete phenotypes in lag time for bacterial long-term fitness.
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Affiliation(s)
- Yusuke Himeoka
- The Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Namiko Mitarai
- The Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
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159
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Moreno-Gámez S, Dal Co A, van Vliet S, Ackermann M. Microfluidics for Single-Cell Study of Antibiotic Tolerance and Persistence Induced by Nutrient Limitation. Methods Mol Biol 2021; 2357:107-124. [PMID: 34590255 DOI: 10.1007/978-1-0716-1621-5_8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Nutrient limitation is one of the most common triggers of antibiotic tolerance and persistence. Here, we present two microfluidic setups to study how spatial and temporal variation in nutrient availability lead to increased survival of bacteria to antibiotics. The first setup is designed to mimic the growth dynamics of bacteria in spatially structured populations (e.g., biofilms) and can be used to study how spatial gradients in nutrient availability, created by the collective metabolic activity of a population, increase antibiotic tolerance. The second setup captures the dynamics of feast-and-famine cycles that bacteria recurrently encounter in nature, and can be used to study how phenotypic heterogeneity in growth resumption after starvation increases survival of clonal bacterial populations. In both setups, the growth rates and metabolic activity of bacteria can be measured at the single-cell level. This is useful to build a mechanistic understanding of how spatiotemporal variation in nutrient availability triggers bacteria to enter phenotypic states that increase their tolerance to antibiotics.
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Affiliation(s)
- Stefany Moreno-Gámez
- Department of Environmental Systems Science, Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, Zurich, Switzerland.
- Department of Environmental Microbiology, Eawag, Dübendorf, Switzerland.
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands.
| | - Alma Dal Co
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | | | - Martin Ackermann
- Department of Environmental Systems Science, Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, Zurich, Switzerland
- Department of Environmental Microbiology, Eawag, Dübendorf, Switzerland
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160
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Bleichert P, Bütof L, Rückert C, Herzberg M, Francisco R, Morais PV, Grass G, Kalinowski J, Nies DH. Mutant Strains of Escherichia coli and Methicillin-Resistant Staphylococcus aureus Obtained by Laboratory Selection To Survive on Metallic Copper Surfaces. Appl Environ Microbiol 2020; 87:e01788-20. [PMID: 33067196 PMCID: PMC7755237 DOI: 10.1128/aem.01788-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 10/09/2020] [Indexed: 01/27/2023] Open
Abstract
Artificial laboratory evolution was used to produce mutant strains of Escherichia coli and methicillin-resistant Staphylococcus aureus (MRSA) able to survive on antimicrobial metallic copper surfaces. These mutants were 12- and 60-fold less susceptible to the copper-mediated contact killing process than their respective parent strains. Growth levels of the mutant and its parent in complex growth medium were similar. Tolerance to copper ions of the mutants was unchanged. The mutant phenotype remained stable over about 250 generations under nonstress conditions. The mutants and their respective parental strains accumulated copper released from the metallic surfaces to similar extents. Nevertheless, only the parental strains succumbed to copper stress when challenged on metallic copper surfaces, suffering complete destruction of the cell structure. Whole-genome sequencing and global transcriptome analysis were used to decipher the genetic alterations in the mutant strains; however, these results did not explain the copper-tolerance phenotypes on the systemic level. Instead, the mutants shared features with those of stressed bacterial subpopulations entering the early or "shallow" persister state. In contrast to the canonical persister state, however, the ability to survive on solid copper surfaces was adopted by the majority of the mutant strain population. This indicated that application of solid copper surfaces in hospitals and elsewhere has to be accompanied by strict cleaning regimens to keep the copper surfaces active and prevent evolution of tolerant mutant strains.IMPORTANCE Microbes are rapidly killed on solid copper surfaces by contact killing. Copper surfaces thus have an important role to play in preventing the spread of nosocomial infections. Bacteria adapt to challenging natural and clinical environments through evolutionary processes, for instance, by acquisition of beneficial spontaneous mutations. We wish to address the question of whether mutants can be selected that have evolved to survive contact killing on solid copper surfaces. We isolated such mutants from Escherichia coli and methicillin-resistant Staphylococcus aureus (MRSA) by artificial laboratory evolution. The ability to survive on solid copper surfaces was a stable phenotype of the mutant population and not restricted to a small subpopulation. As a consequence, standard operation procedures with strict hygienic measures are extremely important to prevent the emergence and spread of copper-surface-tolerant persister-like bacterial strains if copper surfaces are to be sustainably used to limit the spread of pathogenic bacteria, e.g., to curb nosocomial infections.
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Affiliation(s)
| | - Lucy Bütof
- Martin-Luther University Halle-Wittenberg, Institute of Molecular Microbiology, Halle (Saale), Germany
| | | | - Martin Herzberg
- Martin-Luther University Halle-Wittenberg, Institute of Molecular Microbiology, Halle (Saale), Germany
| | - Romeu Francisco
- CEMMPRE-Centre for Mechanical Engineering, Materials and Processes, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Paula V Morais
- CEMMPRE-Centre for Mechanical Engineering, Materials and Processes, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Gregor Grass
- Bundeswehr Institute of Microbiology, Munich, Germany
| | - Jörn Kalinowski
- Bielefeld University, Center for Biotechnology, Bielefeld, Germany
| | - Dietrich H Nies
- Martin-Luther University Halle-Wittenberg, Institute of Molecular Microbiology, Halle (Saale), Germany
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161
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Štumpf S, Hostnik G, Primožič M, Leitgeb M, Bren U. Generation Times of E. coli Prolong with Increasing Tannin Concentration while the Lag Phase Extends Exponentially. PLANTS (BASEL, SWITZERLAND) 2020; 9:plants9121680. [PMID: 33271746 PMCID: PMC7760653 DOI: 10.3390/plants9121680] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 11/27/2020] [Accepted: 11/29/2020] [Indexed: 05/10/2023]
Abstract
The current study examines the effect of tannins and tannin extracts on the lag phase duration, growth rate, and generation time of Escherichia coli. Effects of castalagin, vescalagin, gallic acid, Colistizer, tannic acid as well as chestnut, mimosa, and quebracho extracts were determined on E. coli's growth phases using the broth microdilution method and obtained by turbidimetric measurements. E. coli responds to the stress caused by the investigated antimicrobial agents with reduced growth rates, longer generation times, and extended lag phases. Prolongation of the lag phase was relatively small at low tannin concentrations, while it became more pronounced at concentrations above half the MIC. Moreover, for the first time, it was observed that lag time extensions follow a strict exponential relationship with increasing tannin concentrations. This feature is very likely a direct consequence of the tannin complexation of certain essential ions from the growth medium, making them unavailable to E. coli for its growth.
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Affiliation(s)
- Sara Štumpf
- Faculty of Chemistry and Chemical Engineering, University of Maribor, Maribor 2000, Slovenia; (S.Š.); (G.H.); (M.P.); (M.L.)
| | - Gregor Hostnik
- Faculty of Chemistry and Chemical Engineering, University of Maribor, Maribor 2000, Slovenia; (S.Š.); (G.H.); (M.P.); (M.L.)
| | - Mateja Primožič
- Faculty of Chemistry and Chemical Engineering, University of Maribor, Maribor 2000, Slovenia; (S.Š.); (G.H.); (M.P.); (M.L.)
| | - Maja Leitgeb
- Faculty of Chemistry and Chemical Engineering, University of Maribor, Maribor 2000, Slovenia; (S.Š.); (G.H.); (M.P.); (M.L.)
- Faculty of Medicine, University of Maribor, Maribor 2000, Slovenia
| | - Urban Bren
- Faculty of Chemistry and Chemical Engineering, University of Maribor, Maribor 2000, Slovenia; (S.Š.); (G.H.); (M.P.); (M.L.)
- Faculty of Mathematics, Natural Sciences and Information Technologies, University of Primorska, Koper 6000, Slovenia
- Correspondence: ; Tel.: +386-2-2294-421
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162
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Chernova OA, Chernov VM, Mouzykantov AA, Baranova NB, Edelstein IA, Aminov RI. Antimicrobial drug resistance mechanisms among Mollicutes. Int J Antimicrob Agents 2020; 57:106253. [PMID: 33264670 DOI: 10.1016/j.ijantimicag.2020.106253] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 07/08/2020] [Accepted: 11/22/2020] [Indexed: 12/11/2022]
Abstract
Representatives of the Mollicutes class are the smallest, wall-less bacteria capable of independent reproduction. They are widespread in nature, most are commensals, and some are pathogens of humans, animals and plants. They are also the main contaminants of cell cultures and vaccine preparations. Despite limited biosynthetic capabilities, they are highly adaptable and capable of surviving under various stress and extreme conditions, including antimicrobial selective pressure. This review describes current understanding of antibiotic resistance (ABR) mechanisms in Mollicutes. Protective mechanisms in these bacteria include point mutations, which may include non-target genes, and unique gene exchange mechanisms, contributing to transfer of ABR genes. Better understanding of the mechanisms of emergence and dissemination of ABR in Mollicutes is crucial to control these hypermutable bacteria and prevent the occurrence of highly ABR strains.
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Affiliation(s)
- Olga A Chernova
- Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Centre of RAS, Kazan, Russian Federation
| | - Vladislav M Chernov
- Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Centre of RAS, Kazan, Russian Federation
| | - Alexey A Mouzykantov
- Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Centre of RAS, Kazan, Russian Federation
| | - Natalya B Baranova
- Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Centre of RAS, Kazan, Russian Federation
| | - Inna A Edelstein
- Smolensk State Medical University, Ministry of Health of Russian Federation, Smolensk, Russian Federation
| | - Rustam I Aminov
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK; Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russian Federation.
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163
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Rivera SL, Espaillat A, Aditham AK, Shieh P, Muriel-Mundo C, Kim J, Cava F, Siegrist MS. Chemically Induced Cell Wall Stapling in Bacteria. Cell Chem Biol 2020; 28:213-220.e4. [PMID: 33238158 DOI: 10.1016/j.chembiol.2020.11.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 09/09/2020] [Accepted: 11/06/2020] [Indexed: 12/16/2022]
Abstract
Transpeptidation reinforces the structure of cell-wall peptidoglycan, an extracellular heteropolymer that protects bacteria from osmotic lysis. The clinical success of transpeptidase-inhibiting β-lactam antibiotics illustrates the essentiality of these cross-linkages for cell-wall integrity, but the presence of multiple, seemingly redundant transpeptidases in many species makes it challenging to determine cross-link function. Here, we present a technique to link peptide strands by chemical rather than enzymatic reaction. We employ biocompatible click chemistry to induce triazole formation between azido- and alkynyl-d-alanine residues that are metabolically installed in the peptidoglycan of Gram-positive or Gram-negative bacteria. Synthetic triazole cross-links can be visualized using azidocoumarin-d-alanine, an amino acid derivative that undergoes fluorescent enhancement upon reaction with terminal alkynes. Cell-wall stapling protects Escherichia coli from treatment with the broad-spectrum β-lactams ampicillin and carbenicillin. Chemical control of cell-wall structure in live bacteria can provide functional insights that are orthogonal to those obtained by genetics.
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Affiliation(s)
- Sylvia L Rivera
- Department of Microbiology, University of Massachusetts, Amherst, MA 01003, USA
| | - Akbar Espaillat
- Laboratory for Molecular Infection Medicine, Department of Molecular Biology, Umeå University, Umeå 90187, Sweden
| | - Arjun K Aditham
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA; Stanford ChEM-H (Chemistry, Engineering, and Medicine for Human Health), Stanford University, Stanford, CA 94305, USA
| | - Peyton Shieh
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Chris Muriel-Mundo
- Department of Microbiology, University of Massachusetts, Amherst, MA 01003, USA
| | - Justin Kim
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Felipe Cava
- Laboratory for Molecular Infection Medicine, Department of Molecular Biology, Umeå University, Umeå 90187, Sweden.
| | - M Sloan Siegrist
- Department of Microbiology, University of Massachusetts, Amherst, MA 01003, USA; Molecular and Cellular Biology Program, University of Massachusetts, Amherst, MA 01003, USA.
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164
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Pletnev P, Pupov D, Pshanichnaya L, Esyunina D, Petushkov I, Nesterchuk M, Osterman I, Rubtsova M, Mardanov A, Ravin N, Sergiev P, Kulbachinskiy A, Dontsova O. Rewiring of growth-dependent transcription regulation by a point mutation in region 1.1 of the housekeeping σ factor. Nucleic Acids Res 2020; 48:10802-10819. [PMID: 32997144 PMCID: PMC7641759 DOI: 10.1093/nar/gkaa798] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 09/09/2020] [Accepted: 09/12/2020] [Indexed: 01/24/2023] Open
Abstract
In bacteria, rapid adaptation to changing environmental conditions depends on the interplay between housekeeping and alternative σ factors, responsible for transcription of specific regulons by RNA polymerase (RNAP). In comparison with alternative σ factors, primary σs contain poorly conserved region 1.1, whose functions in transcription are only partially understood. We found that a single mutation in region 1.1 in Escherichia coli σ70 rewires transcription regulation during cell growth resulting in profound phenotypic changes. Despite its destabilizing effect on promoter complexes, this mutation increases the activity of rRNA promoters and also decreases RNAP sensitivity to the major regulator of stringent response DksA. Using total RNA sequencing combined with single-cell analysis of gene expression we showed that changes in region 1.1 disrupt the balance between the "greed" and "fear" strategies thus making the cells more susceptible to environmental threats and antibiotics. Our results reveal an unexpected role of σ region 1.1 in growth-dependent transcription regulation and suggest that changes in this region may facilitate rapid switching of RNAP properties in evolving bacterial populations.
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Affiliation(s)
- Philipp Pletnev
- Department of Chemistry, Lomonosov Moscow State University, Moscow 119992, Russia.,Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Moscow 117997, Russia
| | - Danil Pupov
- Institute of Molecular Genetics, Russian Academy of Sciences, Moscow,123182, Russia
| | | | - Daria Esyunina
- Institute of Molecular Genetics, Russian Academy of Sciences, Moscow,123182, Russia
| | - Ivan Petushkov
- Institute of Molecular Genetics, Russian Academy of Sciences, Moscow,123182, Russia
| | - Mikhail Nesterchuk
- Skolkovo Institute of Science and Technology, Skolkovo, Moscow Region 143028, Russia
| | - Ilya Osterman
- Department of Chemistry, Lomonosov Moscow State University, Moscow 119992, Russia.,Skolkovo Institute of Science and Technology, Skolkovo, Moscow Region 143028, Russia
| | - Maria Rubtsova
- Department of Chemistry, Lomonosov Moscow State University, Moscow 119992, Russia.,Skolkovo Institute of Science and Technology, Skolkovo, Moscow Region 143028, Russia
| | - Andrey Mardanov
- Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Nikolai Ravin
- Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Petr Sergiev
- Department of Chemistry, Lomonosov Moscow State University, Moscow 119992, Russia.,Skolkovo Institute of Science and Technology, Skolkovo, Moscow Region 143028, Russia.,Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119992, Russia.,Institute of Functional Genomics, Lomonosov Moscow State University, Moscow 119992, Russia
| | - Andrey Kulbachinskiy
- Institute of Molecular Genetics, Russian Academy of Sciences, Moscow,123182, Russia
| | - Olga Dontsova
- Department of Chemistry, Lomonosov Moscow State University, Moscow 119992, Russia.,Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Moscow 117997, Russia.,Skolkovo Institute of Science and Technology, Skolkovo, Moscow Region 143028, Russia.,Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119992, Russia
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165
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Hör J, Di Giorgio S, Gerovac M, Venturini E, Förstner KU, Vogel J. Grad-seq shines light on unrecognized RNA and protein complexes in the model bacterium Escherichia coli. Nucleic Acids Res 2020; 48:9301-9319. [PMID: 32813020 PMCID: PMC7498339 DOI: 10.1093/nar/gkaa676] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 07/29/2020] [Accepted: 08/14/2020] [Indexed: 12/21/2022] Open
Abstract
Stable protein complexes, including those formed with RNA, are major building blocks of every living cell. Escherichia coli has been the leading bacterial organism with respect to global protein-protein networks. Yet, there has been no global census of RNA/protein complexes in this model species of microbiology. Here, we performed Grad-seq to establish an RNA/protein complexome, reconstructing sedimentation profiles in a glycerol gradient for ∼85% of all E. coli transcripts and ∼49% of the proteins. These include the majority of small noncoding RNAs (sRNAs) detectable in this bacterium as well as the general sRNA-binding proteins, CsrA, Hfq and ProQ. In presenting use cases for utilization of these RNA and protein maps, we show that a stable association of RyeG with 30S ribosomes gives this seemingly noncoding RNA of prophage origin away as an mRNA of a toxic small protein. Similarly, we show that the broadly conserved uncharacterized protein YggL is a 50S subunit factor in assembled 70S ribosomes. Overall, this study crucially extends our knowledge about the cellular interactome of the primary model bacterium E. coli through providing global RNA/protein complexome information and should facilitate functional discovery in this and related species.
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Affiliation(s)
- Jens Hör
- Institute of Molecular Infection Biology, University of Würzburg, D-97080 Würzburg, Germany
| | - Silvia Di Giorgio
- Institute of Molecular Infection Biology, University of Würzburg, D-97080 Würzburg, Germany.,ZB MED - Information Centre for Life Sciences, D-50931 Cologne, Germany
| | - Milan Gerovac
- Institute of Molecular Infection Biology, University of Würzburg, D-97080 Würzburg, Germany
| | - Elisa Venturini
- Institute of Molecular Infection Biology, University of Würzburg, D-97080 Würzburg, Germany
| | - Konrad U Förstner
- ZB MED - Information Centre for Life Sciences, D-50931 Cologne, Germany.,TH Köln, Faculty of Information Science and Communication Studies, D-50678 Cologne, Germany
| | - Jörg Vogel
- Institute of Molecular Infection Biology, University of Würzburg, D-97080 Würzburg, Germany.,Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz Centre for Infection Research (HZI), D-97080 Würzburg, Germany
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166
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Liu Y, Yang K, Zhang H, Jia Y, Wang Z. Combating Antibiotic Tolerance Through Activating Bacterial Metabolism. Front Microbiol 2020; 11:577564. [PMID: 33193198 PMCID: PMC7642520 DOI: 10.3389/fmicb.2020.577564] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 09/25/2020] [Indexed: 12/18/2022] Open
Abstract
The emergence of antibiotic tolerance enables genetically susceptible bacteria to withstand the killing by clinically relevant antibiotics. As is reported, an increasing body of evidence sheds light on the critical and underappreciated role of antibiotic tolerance in the disease burden of bacterial infections. Considering this tense situation, new therapeutic strategies are urgently required for combating antibiotic tolerance. Herein, we provide an insightful illustration to distinguish between antibiotic resistance and tolerance, and highlight its clinical significance and complexities of drug-tolerant bacteria. Then, we discuss the close relationship between antibiotic tolerance and bacterial metabolism. As such, a bacterial metabolism-based approach was proposed to counter antibiotic tolerance. These exogenous metabolites including amino acids, tricarboxylic acid cycle (TCA cycle) metabolites, and nucleotides effectively activate bacterial metabolism and convert the tolerant cells to sensitive cells, and eventually restore antibiotic efficacy. A better understanding of molecular mechanisms of antibiotic tolerance particularly in vivo would substantially drive the development of novel strategies targeting bacterial metabolism.
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Affiliation(s)
- Yuan Liu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China.,Institute of Comparative Medicine, Yangzhou University, Yangzhou, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, China.,Joint International Research Laboratory of Agriculture and Agri-Product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou, China
| | - Kangni Yang
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
| | - Haijie Zhang
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
| | - Yuqian Jia
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
| | - Zhiqiang Wang
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, China.,Joint International Research Laboratory of Agriculture and Agri-Product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou, China
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167
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Wang P, Zhou R, Zhou R, Recek N, Prasad K, Speight R, Richard D, Cullen PJ, Thompson EW, Ostrikov KK, Bazaka K. Chemo-Radiative Stress of Plasma as a Modulator of Charge-Dependent Nanodiamond Cytotoxicity. ACS APPLIED BIO MATERIALS 2020; 3:7202-7210. [DOI: 10.1021/acsabm.0c01000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Peiyu Wang
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD 4000, Australia
- Faculty of Health, School of Biomedical Sciences, Queensland University of Technology, Brisbane, QLD 4000, Australia
- Translational Research Institute, Brisbane, QLD 4102, Australia
| | - Rusen Zhou
- Science and Engineering Faculty, Queensland University of Technology, Brisbane, QLD 4000, Australia
| | - Renwu Zhou
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD 4000, Australia
- Science and Engineering Faculty, Queensland University of Technology, Brisbane, QLD 4000, Australia
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, NSW 2006, Australia
| | - Nina Recek
- Science and Engineering Faculty, Queensland University of Technology, Brisbane, QLD 4000, Australia
- Department of Surface Engineering and Optoelectronics, Jožef Stefan Institute, Ljubljana SI-1000, Slovenia
| | - Karthika Prasad
- Science and Engineering Faculty, Queensland University of Technology, Brisbane, QLD 4000, Australia
| | - Robert Speight
- Science and Engineering Faculty, Queensland University of Technology, Brisbane, QLD 4000, Australia
| | - Derek Richard
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD 4000, Australia
- Faculty of Health, School of Biomedical Sciences, Queensland University of Technology, Brisbane, QLD 4000, Australia
- Translational Research Institute, Brisbane, QLD 4102, Australia
| | - Patrick J. Cullen
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, NSW 2006, Australia
| | - Erik W. Thompson
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD 4000, Australia
- Faculty of Health, School of Biomedical Sciences, Queensland University of Technology, Brisbane, QLD 4000, Australia
- Translational Research Institute, Brisbane, QLD 4102, Australia
| | - Kostya Ken Ostrikov
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD 4000, Australia
- Science and Engineering Faculty, Queensland University of Technology, Brisbane, QLD 4000, Australia
| | - Kateryna Bazaka
- Science and Engineering Faculty, Queensland University of Technology, Brisbane, QLD 4000, Australia
- Research School of Electrical, Energy and Materials Engineering, The Australian National University, Canberra, ACT 2000, Australia
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168
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Wesgate R, Evangelista C, Atkinson R, Shepard A, Adegoke O, Maillard JY. Understanding the risk of emerging bacterial resistance to over the counter antibiotics in topical sore throat medicines. J Appl Microbiol 2020; 129:916-925. [PMID: 32352619 DOI: 10.1111/jam.14682] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 04/01/2020] [Accepted: 04/26/2020] [Indexed: 11/27/2022]
Abstract
AIMS The aims of this study were to explore the development of bacterial resistance and cross-resistance in four common human pathogens following realistic exposure to antibiotics found in over-the-counter (OTC) sore throat medicines: gramicidin, neomycin, bacitracin and tyrothricin. METHODS AND RESULTS Bacterial exposure to in-use (concentration in the product before use) and diluted concentration (i.e. during use) of antibiotic where conducted in broth for 24 h or until growth was visible. The changes in bacterial susceptibility profile before and after exposure was determined using standardized ISO microdilution broth. Antibiotic testing was performed according to EUCAST guidelines. We demonstrated that test bacteria were able to survive exposure to the in-use concentrations of some antibiotics used in OTC medicines. Exposure to during use concentrations of bacitracin resulted in stable increase in minimal inhibitory concentration (MIC) (>8-fold) in Staphylococcus aureus and Acinetobacter baumannii. Exposure to tyrothricin resulted in a stable increase in MIC (2·4-fold) in Klebsiella pneumoniae, and exposure to neomycin resulted in a stable increase MIC (5000-fold higher than the baseline) in Streptococcus pyogenes. Clinical cross-resistance to other antibiotics (ciprofloxacin, fusidic acid, gentamicin, cefpodoxime, amoxicillin/clavulanic acid and cefotaxime) was also demonstrated following exposure to bacitracin or tyrothricin. Bacitracin exposure lead to a stable bacterial resistance after 10 passages. CONCLUSIONS Our results indicate that OTC antibiotic medicines have the potential to drive resistance and cross-resistance in vitro. SIGNIFICANCE AND IMPACT OF THE STUDY Tackling antibiotic resistance is a high worldwide priority. It is widely accepted that the overuse and misuse of antibiotics increase the risk of the development and spread of antibiotic resistance within communities. A number of OTC sore throat products, widely available across the world for topical use in respiratory indications, contain locally delivered antibiotics. Our findings showed that these antibiotics in OTC medicines present a risk for emerging cross-resistance in a number of bacterial respiratory pathogens.
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Affiliation(s)
- R Wesgate
- School of Pharmacy & Pharmaceutical Sciences, Cardiff University, Cardiff, UK
| | - C Evangelista
- School of Pharmacy & Pharmaceutical Sciences, Cardiff University, Cardiff, UK
| | | | | | | | - J-Y Maillard
- School of Pharmacy & Pharmaceutical Sciences, Cardiff University, Cardiff, UK
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169
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Sasaki H, Ishikawa H, Itoh T, Arano M, Hirata K, Ueshiba H. Penicillin-Binding Proteins and Associated Protein Mutations Confer Oxacillin/Cefoxitin Tolerance in Borderline Oxacillin-Resistant Staphylococcus aureus. Microb Drug Resist 2020; 27:590-595. [DOI: 10.1089/mdr.2020.0191] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Affiliation(s)
- Hiraku Sasaki
- Department of Health Science, Faculty of Health and Sports Science, Juntendo University, Inzai, Japan
| | - Hiroki Ishikawa
- Department of Microbiology and Immunology, Showa University School of Medicine, Shinagawa-ku, Japan
| | - Taisuke Itoh
- Department of Health Science, Faculty of Health and Sports Science, Juntendo University, Inzai, Japan
| | - Makoto Arano
- Department of Health Science, Faculty of Health and Sports Science, Juntendo University, Inzai, Japan
| | - Koya Hirata
- Department of Health Science, Faculty of Health and Sports Science, Juntendo University, Inzai, Japan
| | - Hidehiro Ueshiba
- Department of Microbiology and Immunology, Tokyo Women's Medical University School of Medicine, Shinjuku-ku, Japan
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170
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Liu Y, Li R, Xiao X, Wang Z. Bacterial metabolism-inspired molecules to modulate antibiotic efficacy. J Antimicrob Chemother 2020; 74:3409-3417. [PMID: 31211378 DOI: 10.1093/jac/dkz230] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The decreasing antibiotic susceptibility of bacterial pathogens calls for novel antimicrobial therapies. Traditional screening pathways based on drug-target interaction have gradually reached the stage of diminishing returns. Thus, novel strategies are urgently needed in the fight against antibiotic-refractory bacteria, particularly for tolerant bacteria. Recently, evidence has accumulated demonstrating that microbial changes caused by bacterial metabolic processes significantly modulate antibiotic killing. A better understanding of these bacterial metabolic processes is indicating a need to screen novel metabolic modulators as potential antibiotic adjuvants. In this review, we describe the state of our current knowledge about how these bacterial metabolism-inspired molecules affect antibiotic efficacy, including potentiation and inhibition activity. In addition, the challenges faced and prospects for bringing them into clinic are also discussed. These examples may provide candidates or targets for the development of novel antibiotic adjuvants.
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Affiliation(s)
- Yuan Liu
- Institute of Comparative Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, China
| | - Ruichao Li
- Institute of Comparative Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, China
| | - Xia Xiao
- Institute of Comparative Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, China
| | - Zhiqiang Wang
- Institute of Comparative Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, China
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171
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Bagamery LE, Justman QA, Garner EC, Murray AW. A Putative Bet-Hedging Strategy Buffers Budding Yeast against Environmental Instability. Curr Biol 2020; 30:4563-4578.e4. [PMID: 32976801 DOI: 10.1016/j.cub.2020.08.092] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Revised: 07/20/2020] [Accepted: 08/26/2020] [Indexed: 12/19/2022]
Abstract
To grow and divide, cells must extract resources from dynamic and unpredictable environments. Many organisms use different metabolic strategies for distinct contexts. Budding yeast can produce ATP from carbon sources by mechanisms that prioritize either speed (fermentation) or yield (respiration). Withdrawing glucose from exponentially growing cells reveals variability in their ability to switch from fermentation to respiration. We observe two subpopulations of glucose-starved cells: recoverers, which rapidly adapt and resume growth, and arresters, which enter a shock state characterized by deformation of many cellular structures, including mitochondria. These states are heritable, and on high glucose, arresters grow and divide faster than recoverers. Recoverers have a fitness advantage during a carbon source shift but are less fit in a constant, high-glucose environment, and we observe natural variation in the frequency of the two states across wild yeast strains. These experiments suggest that bet hedging has evolved in budding yeast.
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Affiliation(s)
- Laura E Bagamery
- Department of Molecular and Cellular Biology, Harvard University, 52 Oxford Street, Cambridge, MA 02138, USA
| | - Quincey A Justman
- Department of Molecular and Cellular Biology, Harvard University, 52 Oxford Street, Cambridge, MA 02138, USA
| | - Ethan C Garner
- Department of Molecular and Cellular Biology, Harvard University, 52 Oxford Street, Cambridge, MA 02138, USA.
| | - Andrew W Murray
- Department of Molecular and Cellular Biology, Harvard University, 52 Oxford Street, Cambridge, MA 02138, USA.
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172
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Liu X, Liu F, Ding S, Shen J, Zhu K. Sublethal Levels of Antibiotics Promote Bacterial Persistence in Epithelial Cells. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2020; 7:1900840. [PMID: 32999821 PMCID: PMC7509632 DOI: 10.1002/advs.201900840] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 05/17/2020] [Indexed: 05/21/2023]
Abstract
Antibiotic therapy and host cells frequently fail to eliminate invasive bacterial pathogens due to the emergence of antibiotic resistance, resulting in the relapse and recurrence of infections. Bacteria evolve various strategies to persist and survive in epithelial cells, a front-line barrier of host tissues counteracting invasion; however, it remains unclear how bacteria hijack cellular responses to promote cytoplasmic survival under antibiotic therapy. Here, it is demonstrated that extracellular bacteria show invasive behavior and survive in epithelial cells in both in vivo and in vitro models, to increase antibiotic tolerance. In turn, sublethal levels of antibiotics increase bacterial invasion through promoting the production of bacterial virulence factors. Furthermore, antibiotic treatments interrupt lysosomal acidification in autophagy due to the internalized bacteria, using Bacillus cereus and ciprofloxacin as a model. In addition, it is found that sublethal levels of ciprofloxacin cause mitochondrial dysfunction and reactive oxygen species (ROS) accumulation to impair lysosomal vascular tape ATPase (V-ATPase) to further promote bacterial persistence. Collectively, these results highlight the potential of host cells mediated antibiotic tolerance, which markedly compromises antibiotic efficacy and worsens the outcomes of infection.
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Affiliation(s)
- Xiaoye Liu
- Beijing Advanced Innovation Center for Food Nutrition and Human HealthCollege of Veterinary MedicineChina Agricultural UniversityNo. 2 Yuanmingyuan West RoadBeijing100193China
- National Center for Veterinary Drug Safety EvaluationCollege of Veterinary MedicineChina Agricultural UniversityBeijing100193China
| | - Fei Liu
- Beijing Advanced Innovation Center for Food Nutrition and Human HealthCollege of Veterinary MedicineChina Agricultural UniversityNo. 2 Yuanmingyuan West RoadBeijing100193China
| | - Shuangyang Ding
- National Center for Veterinary Drug Safety EvaluationCollege of Veterinary MedicineChina Agricultural UniversityBeijing100193China
- Beijing Key Laboratory of Detection Technology for Animal‐Derived Food Safety and Beijing Laboratory for Food Quality and SafetyChina Agricultural UniversityBeijing100193China
| | - Jianzhong Shen
- Beijing Advanced Innovation Center for Food Nutrition and Human HealthCollege of Veterinary MedicineChina Agricultural UniversityNo. 2 Yuanmingyuan West RoadBeijing100193China
- National Center for Veterinary Drug Safety EvaluationCollege of Veterinary MedicineChina Agricultural UniversityBeijing100193China
- Beijing Key Laboratory of Detection Technology for Animal‐Derived Food Safety and Beijing Laboratory for Food Quality and SafetyChina Agricultural UniversityBeijing100193China
| | - Kui Zhu
- Beijing Advanced Innovation Center for Food Nutrition and Human HealthCollege of Veterinary MedicineChina Agricultural UniversityNo. 2 Yuanmingyuan West RoadBeijing100193China
- National Center for Veterinary Drug Safety EvaluationCollege of Veterinary MedicineChina Agricultural UniversityBeijing100193China
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173
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Moldoveanu AL, Rycroft JA, Helaine S. Impact of bacterial persisters on their host. Curr Opin Microbiol 2020; 59:65-71. [PMID: 32866708 DOI: 10.1016/j.mib.2020.07.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 07/18/2020] [Indexed: 02/06/2023]
Abstract
The rise of antibiotic failure poses a severe threat to global health. There is growing concern that this failure is not solely driven by stable antibiotic resistance but also by a subpopulation of transiently non-growing, antibiotic tolerant bacteria. These 'persisters' have been proposed to seed relapsing infections, an important clinical outcome of treatment failure - although definitive evidence for this direct link remains elusive. Recent advances in the field have revealed the complex nature of intra-host persisters which drive their high adaptability through biosynthetic activity. These features of persisters contribute to evolution of antimicrobial resistance and modulation of host immune responses, despite clinically efficacious treatment.
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Affiliation(s)
- Ana L Moldoveanu
- Centre for Molecular Bacteriology and Infection, Imperial College London, South Kensington, London SW7 2AZ, UK
| | - Julian A Rycroft
- Department of Microbiology, Harvard Medical School, 77 Ave Pasteur, Boston, MA 02115, USA
| | - Sophie Helaine
- Department of Microbiology, Harvard Medical School, 77 Ave Pasteur, Boston, MA 02115, USA.
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174
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Besnard F, Picao-Osorio J, Dubois C, Félix MA. A broad mutational target explains a fast rate of phenotypic evolution. eLife 2020; 9:54928. [PMID: 32851977 PMCID: PMC7556874 DOI: 10.7554/elife.54928] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 08/27/2020] [Indexed: 12/30/2022] Open
Abstract
The rapid evolution of a trait in a clade of organisms can be explained by the sustained action of natural selection or by a high mutational variance, that is the propensity to change under spontaneous mutation. The causes for a high mutational variance are still elusive. In some cases, fast evolution depends on the high mutation rate of one or few loci with short tandem repeats. Here, we report on the fastest evolving cell fate among vulva precursor cells in Caenorhabditis nematodes, that of P3.p. We identify and validate causal mutations underlying P3.p's high mutational variance. We find that these positions do not present any characteristics of a high mutation rate, are scattered across the genome and the corresponding genes belong to distinct biological pathways. Our data indicate that a broad mutational target size is the cause of the high mutational variance and of the corresponding fast phenotypic evolutionary rate. Heritable characteristics or traits of a group of organisms, for example the large brain size of primates or the hooves of a horse, are determined by genes, the environment, and by the interactions between them. Traits can change over time and generations when enough mutations in these genes have spread in a species to result in visible differences. However, some traits, such as the large brain of primates, evolve faster than others, but why this is the case has been unclear. It could be that a few specific genes important for that trait in question mutate at a high rate, or, that many genes affect the trait, creating a lot of variation for natural selection to choose from. Here, Besnard, Picao-Osorio et al. studied the roundworm Caenorhabditis elegans to better understand the causes underlying the different rates of trait evolution. These worms have a short life cycle and evolve quickly over many generations, making them an ideal candidate for studying mutation rates in different traits. Previous studies have shown that one of C. elegans’ six cells of the reproductive system evolves faster than the others. To investigate this further, Besnard, Picao-Osorio et al. analysed the genetic mutations driving change in this cell in 250 worm generations. The results showed that five mutations in five different genes – all responsible for different processes in the cells – were behind the supercharged evolution of this particular cell. This suggests that fast evolution results from natural selection acting upon a collection of genes, rather than one gene, and that many genes and pathways shape this trait. In conclusion, these results demonstrate that how traits are coded at the molecular level, in one gene or many, can influence the rate at which they evolve.
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Affiliation(s)
- Fabrice Besnard
- Institut de Biologie de l'École Normale Supérieure, CNRS, Inserm, Paris, France.,Laboratoire Reproduction et Développement des Plantes, Univ Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRAE, Inria, Lyon, France
| | - Joao Picao-Osorio
- Institut de Biologie de l'École Normale Supérieure, CNRS, Inserm, Paris, France
| | - Clément Dubois
- Institut de Biologie de l'École Normale Supérieure, CNRS, Inserm, Paris, France
| | - Marie-Anne Félix
- Institut de Biologie de l'École Normale Supérieure, CNRS, Inserm, Paris, France
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175
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Liu Y, Lehnert T, Gijs MAM. Fast antimicrobial susceptibility testing on Escherichia coli by metabolic heat nanocalorimetry. LAB ON A CHIP 2020; 20:3144-3157. [PMID: 32677656 DOI: 10.1039/d0lc00579g] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Fast spreading of antimicrobial resistance is now considered a major global health threat. New technologies are required, enabling rapid diagnostics of bacterial infection combined with fast antimicrobial susceptibility testing (AST) for evaluating the efficiency and dosage of antimicrobial compounds in vitro. This work presents an integrated chip-based isothermal nanocalorimetry platform for direct microbial metabolic heat measurements and evaluates its potential for fast AST. Direct detection of the bacteria-generated heat allows monitoring of metabolic activity and antimicrobial action at subinhibitory concentrations in real-time. The high heat sensitivity of the platform enables bacterial growth detection within only a few hours of incubation, whereas growth inhibition upon administration of antibiotics is revealed by a decrease or the absence of the heat signal. Antimicrobial stress results in lag phase extension and metabolic energy spilling. Oxygen consumption and optical density measurements provide a more holistic insight of the metabolic state and the evolution of bacterial biomass. As a proof-of-concept, a metabolic heat-based AST study on Escherichia coli as model organism with 3 clinically relevant antibiotics is performed and the minimum inhibitory concentrations are determined.
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Affiliation(s)
- Yang Liu
- Laboratory of Microsystems, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
| | - Thomas Lehnert
- Laboratory of Microsystems, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
| | - Martin A M Gijs
- Laboratory of Microsystems, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
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176
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Rocha-Granados MC, Zenick B, Englander HE, Mok WWK. The social network: Impact of host and microbial interactions on bacterial antibiotic tolerance and persistence. Cell Signal 2020; 75:109750. [PMID: 32846197 DOI: 10.1016/j.cellsig.2020.109750] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 08/07/2020] [Accepted: 08/20/2020] [Indexed: 12/13/2022]
Abstract
Antibiotics have vastly improved our quality of life since their discovery and introduction into modern medicine. Yet, widespread use and misuse have compromised the efficacy of these compounds and put our ability to cure infectious diseases in jeopardy. To defend themselves against antibiotics, bacteria have evolved an arsenal of survival strategies. In addition to acquiring mutations and genetic determinants that confer antibiotic resistance, bacteria can respond to environmental cues and adopt reversible phenotypic changes that transiently enhance their ability to survive adverse conditions, including those brought on by antibiotics. These antibiotic tolerant and persistent bacteria, which are prevalent in biofilms and can survive antimicrobial therapy without inheriting resistance, are thought to underlie treatment failure and infection relapse. At infection sites, bacteria encounter a range of signals originating from host immunity and the local microbiota that can induce transcriptomic and metabolic reprogramming. In this review, we will focus on the impact of host factors and microbial interactions on antibiotic tolerance and persistence. We will also outline current efforts in leveraging the knowledge of host-microbe and microbe-microbe interactions in designing therapies that potentiate antibiotic activity and reduce the burden caused by recurrent infections.
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Affiliation(s)
| | - Blesing Zenick
- Department of Molecular Biology & Biophysics, UCONN Health, Farmington, CT, 06032, USA
| | - Hanna E Englander
- Department of Molecular Biology & Biophysics, UCONN Health, Farmington, CT, 06032, USA; Department of Physiology & Neurobiology, University of Connecticut, Storrs, CT 06269-3156, United States of America
| | - Wendy W K Mok
- Department of Molecular Biology & Biophysics, UCONN Health, Farmington, CT, 06032, USA.
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177
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Proteomic Study of the Survival and Resuscitation Mechanisms of Filamentous Persisters in an Evolved Escherichia coli Population from Cyclic Ampicillin Treatment. mSystems 2020; 5:5/4/e00462-20. [PMID: 32723793 PMCID: PMC7394356 DOI: 10.1128/msystems.00462-20] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Through adaptive laboratory evolution (ALE) experiments, it was recently found that when a bacterial population was repetitively treated with antibiotics, they will adapt to the treatment conditions and become tolerant to the drug. In this study, we utilized an ampicillin-tolerant Escherichia coli population isolated from an ALE experiment to study the mechanisms of persistence during ampicillin treatment and resuscitation. Interestingly, the persisters of this population exhibit filamentous morphology upon ampicillin treatment, and the filaments are getting longer over time. Proteomics analysis showed that proteins involved in carbohydrate metabolism are upregulated during antibiotic treatment, in addition to those involved in the oxidative stress response. Bacterial SOS response, which is associated with filamentation, was found to be induced on account of the increasing expression of RecA. Measurement of endogenous reactive oxygen species (ROS) revealed that the population have ∼100-fold less ROS generation under ampicillin treatment than the wild type, leading to a lower mutagenesis rate. Single-cell observations through time-lapse microscopy show that resuscitation of the filaments is stochastic. During resuscitation, proteins involved in the tricarboxylic acid (TCA) cycle, glyoxylate cycle and glycolytic processes, and ATP generation are downregulated, while ribosomal proteins and porins are upregulated in the filaments. One particular protein, ElaB, was upregulated by over 7-fold in the filaments after 3 h of resuspension in fresh medium, but its expression went down after the filaments divided. Knockout of elaB increased persistence on wild-type E. coli, and upon resumption of growth, mutants lacking elaB have a higher fraction of small colony variants (SCVs) than the wild type.IMPORTANCE Persisters are a subpopulation of cells with enhanced survival toward antibiotic treatment and have the ability to resume normal growth when the antibiotic stress is lifted. Although proteomics is the most suitable tool to study them from a system-level perspective, the number of persisters that present naturally is too few for proteomics analysis, and thus the complex mechanisms through which they are able to survive antibiotic stresses and resuscitate in fresh medium remain poorly understood. To overcome that challenge, we studied an evolved Escherichia coli population with elevated persister fraction under ampicillin treatment and obtained its proteome profiles during antibiotic treatment and resuscitation. We discovered that during treatment with ampicillin, this tolerant population employs an active oxidative stress response and exhibits lower ROS levels than the wild type. Moreover, an inner membrane protein which has implications in various stress responses, ElaB, was found to be highly upregulated in the persisters during resuscitation, and its knockout caused increased formation of small colony variants after ampicillin treatment, suggesting that ElaB is important for persisters to resume normal growth.
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178
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Liu Y, Yang K, Jia Y, Shi J, Tong Z, Wang Z. Cysteine Potentiates Bactericidal Antibiotics Activity Against Gram-Negative Bacterial Persisters. Infect Drug Resist 2020; 13:2593-2599. [PMID: 32801796 PMCID: PMC7397215 DOI: 10.2147/idr.s263225] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 07/16/2020] [Indexed: 12/11/2022] Open
Abstract
Purpose Bacterial metabolism regulators offer a novel productive strategy in the eradication of antibiotic refractory bacteria, particularly bacterial persisters. However, the potential of amino acids in the fight against Gram-negative bacterial persisters has not been fully explored. The aim of this study is to investigate the potentiation of amino acids to antibiotics in combating Gram-negative bacterial persisters and to reveal the underlying mechanisms of action. Methods Bactericidal activity of antibiotics in the absence or presence of amino acids was evaluated through detecting the reduction of bacterial CFUs. The ratio of NAD+/NADH in E. coli B2 persisters was determined using assay kit with WST-8. Bacterial respiration and ROS production were measured by the reduction of iodonitrotetrazolium chloride and fluorescent probe 2′,7′-dichlorodihydrofluorescein diacetate, respectively. Results In this study, we found that cysteine possesses excellent synergistic bactericidal activity with ciprofloxacin against multiple Gram-negative bacterial persisters. Furthermore, the potentiation of cysteine was evaluated in exponential and stationary-phase E. coli ATCC 25922 and E. coli B2. Interestingly, cysteine significantly improves three bactericidal antibiotics killing against stationary-phase bacteria, but not exponential-phase bacteria, implying that the effect of cysteine correlates with the metabolic state of bacteria. Mechanistic studies revealed that cysteine accelerates the bacterial TCA cycle and promotes bacterial respiration and ROS production. These metabolic regulation effects of cysteine re-sensitive bacterial persisters to antibiotic killing. Conclusion Collectively, our study highlights the synergistic bactericidal activity of bacterial metabolism regulators such as cysteine with commonly used antibiotics against Gram-negative bacterial persisters.
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Affiliation(s)
- Yuan Liu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China.,Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Joint International Research Laboratory of Agriculture and Agri-Product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China.,Institute of Comparative Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
| | - Kangni Yang
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
| | - Yuqian Jia
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
| | - Jingru Shi
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
| | - Ziwen Tong
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
| | - Zhiqiang Wang
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China.,Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Joint International Research Laboratory of Agriculture and Agri-Product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
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179
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Iwu CD, Korsten L, Okoh AI. The incidence of antibiotic resistance within and beyond the agricultural ecosystem: A concern for public health. Microbiologyopen 2020; 9:e1035. [PMID: 32710495 PMCID: PMC7520999 DOI: 10.1002/mbo3.1035] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 03/09/2020] [Accepted: 03/09/2020] [Indexed: 12/18/2022] Open
Abstract
The agricultural ecosystem creates a platform for the development and dissemination of antimicrobial resistance, which is promoted by the indiscriminate use of antibiotics in the veterinary, agricultural, and medical sectors. This results in the selective pressure for the intrinsic and extrinsic development of the antimicrobial resistance phenomenon, especially within the aquaculture‐animal‐manure‐soil‐water‐plant nexus. The existence of antimicrobial resistance in the environment has been well documented in the literature. However, the possible transmission routes of antimicrobial agents, their resistance genes, and naturally selected antibiotic‐resistant bacteria within and between the various niches of the agricultural environment and humans remain poorly understood. This study, therefore, outlines an overview of the discovery and development of commonly used antibiotics; the timeline of resistance development; transmission routes of antimicrobial resistance in the agro‐ecosystem; detection methods of environmental antimicrobial resistance determinants; factors involved in the evolution and transmission of antibiotic resistance in the environment and the agro‐ecosystem; and possible ways to curtail the menace of antimicrobial resistance.
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Affiliation(s)
- Chidozie D Iwu
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, South Africa.,Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology, University of Fort Hare, Alice, South Africa
| | - Lise Korsten
- Department of Plant and Soil Sciences, Faculty of Natural and Agricultural Sciences, University of Pretoria, Pretoria, South Africa
| | - Anthony I Okoh
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, South Africa.,Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology, University of Fort Hare, Alice, South Africa
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180
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Ahmed MN, Abdelsamad A, Wassermann T, Porse A, Becker J, Sommer MOA, Høiby N, Ciofu O. The evolutionary trajectories of P. aeruginosa in biofilm and planktonic growth modes exposed to ciprofloxacin: beyond selection of antibiotic resistance. NPJ Biofilms Microbiomes 2020; 6:28. [PMID: 32709907 PMCID: PMC7381665 DOI: 10.1038/s41522-020-00138-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Accepted: 07/06/2020] [Indexed: 12/22/2022] Open
Abstract
Ciprofloxacin (CIP) is used to treat Pseudomonas aeruginosa biofilm infections. We showed that the pathways of CIP-resistance development during exposure of biofilms and planktonic P. aeruginosa populations to subinhibitory levels of CIP depend on the mode of growth. In the present study, we analyzed CIP-resistant isolates obtained from previous evolution experiments, and we report a variety of evolved phenotypic and genotypic changes that occurred in parallel with the evolution of CIP-resistance. Cross-resistance to beta-lactam antibiotics was associated with mutations in genes involved in cell-wall recycling (ftsZ, murG); and could also be explained by mutations in the TCA cycle (sdhA) genes and in genes involved in arginine catabolism. We found that CIP-exposed isolates that lacked mutations in quorum-sensing genes and acquired mutations in type IV pili genes maintained swarming motility and lost twitching motility, respectively. Evolved CIP-resistant isolates showed high fitness cost in planktonic competition experiments, yet persisted in the biofilm under control conditions, compared with ancestor isolates and had an advantage when exposed to CIP. Their persistence in biofilm competition experiments in spite of their fitness cost in planktonic growth could be explained by their prolonged lag-phase. Interestingly, the set of mutated genes that we identified in these in vitro-evolved CIP-resistant colonies, overlap with a large number of patho-adaptive genes previously reported in P. aeruginosa isolates from cystic fibrosis (CF) patients. This suggests that the antibiotic stress is contributing to the bacterial evolution in vivo, and that adaptive laboratory evolution can be used to predict the in vivo evolutionary trajectories.
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Affiliation(s)
- Marwa N Ahmed
- Costerton Biofilm Center, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.,Department of Microbiology, Faculty of Agriculture, Cairo University, Giza, Egypt
| | - Ahmed Abdelsamad
- Department of Genetics, Faculty of Agriculture, Cairo University, Giza, Egypt
| | - Tina Wassermann
- Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark
| | - Andreas Porse
- Novo Nordisk Foundation Center for Sustainability, Technical University of Denmark, Lyngby, Denmark
| | - Janna Becker
- Costerton Biofilm Center, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
| | - Morten O A Sommer
- Novo Nordisk Foundation Center for Sustainability, Technical University of Denmark, Lyngby, Denmark
| | - Niels Høiby
- Costerton Biofilm Center, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.,Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark
| | - Oana Ciofu
- Costerton Biofilm Center, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.
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181
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Wide lag time distributions break a trade-off between reproduction and survival in bacteria. Proc Natl Acad Sci U S A 2020; 117:18729-18736. [PMID: 32669426 DOI: 10.1073/pnas.2003331117] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Many microorganisms face a fundamental trade-off between reproduction and survival: Rapid growth boosts population size but makes microorganisms sensitive to external stressors. Here, we show that starved bacteria encountering new resources can break this trade-off by evolving phenotypic heterogeneity in lag time. We quantify the distribution of single-cell lag times of populations of starved Escherichia coli and show that population growth after starvation is primarily determined by the cells with shortest lag due to the exponential nature of bacterial population dynamics. As a consequence, cells with long lag times have no substantial effect on population growth resumption. However, we observe that these cells provide tolerance to stressors such as antibiotics. This allows an isogenic population to break the trade-off between reproduction and survival. We support this argument with an evolutionary model which shows that bacteria evolve wide lag time distributions when both rapid growth resumption and survival under stressful conditions are under selection. Our results can explain the prevalence of antibiotic tolerance by lag and demonstrate that the benefits of phenotypic heterogeneity in fluctuating environments are particularly high when minorities with extreme phenotypes dominate population dynamics.
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182
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Fodor A, Abate BA, Deák P, Fodor L, Gyenge E, Klein MG, Koncz Z, Muvevi J, Ötvös L, Székely G, Vozik D, Makrai L. Multidrug Resistance (MDR) and Collateral Sensitivity in Bacteria, with Special Attention to Genetic and Evolutionary Aspects and to the Perspectives of Antimicrobial Peptides-A Review. Pathogens 2020; 9:pathogens9070522. [PMID: 32610480 PMCID: PMC7399985 DOI: 10.3390/pathogens9070522] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 06/23/2020] [Accepted: 06/23/2020] [Indexed: 12/18/2022] Open
Abstract
Antibiotic poly-resistance (multidrug-, extreme-, and pan-drug resistance) is controlled by adaptive evolution. Darwinian and Lamarckian interpretations of resistance evolution are discussed. Arguments for, and against, pessimistic forecasts on a fatal “post-antibiotic era” are evaluated. In commensal niches, the appearance of a new antibiotic resistance often reduces fitness, but compensatory mutations may counteract this tendency. The appearance of new antibiotic resistance is frequently accompanied by a collateral sensitivity to other resistances. Organisms with an expanding open pan-genome, such as Acinetobacter baumannii, Pseudomonas aeruginosa, and Klebsiella pneumoniae, can withstand an increased number of resistances by exploiting their evolutionary plasticity and disseminating clonally or poly-clonally. Multidrug-resistant pathogen clones can become predominant under antibiotic stress conditions but, under the influence of negative frequency-dependent selection, are prevented from rising to dominance in a population in a commensal niche. Antimicrobial peptides have a great potential to combat multidrug resistance, since antibiotic-resistant bacteria have shown a high frequency of collateral sensitivity to antimicrobial peptides. In addition, the mobility patterns of antibiotic resistance, and antimicrobial peptide resistance, genes are completely different. The integron trade in commensal niches is fortunately limited by the species-specificity of resistance genes. Hence, we theorize that the suggested post-antibiotic era has not yet come, and indeed might never come.
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Affiliation(s)
- András Fodor
- Department of Genetics, University of Szeged, H-6726 Szeged, Hungary;
- Correspondence: or (A.F.); (L.M.); Tel.: +36-(30)-490-9294 (A.F.); +36-(30)-271-2513 (L.M.)
| | - Birhan Addisie Abate
- Ethiopian Biotechnology Institute, Agricultural Biotechnology Directorate, Addis Ababa 5954, Ethiopia;
| | - Péter Deák
- Department of Genetics, University of Szeged, H-6726 Szeged, Hungary;
- Institute of Biochemistry, Biological Research Centre, H-6726 Szeged, Hungary
| | - László Fodor
- Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, P.O. Box 22, H-1581 Budapest, Hungary;
| | - Ervin Gyenge
- Hungarian Department of Biology and Ecology, Faculty of Biology and Geology, Babeș-Bolyai University, 5-7 Clinicilor St., 400006 Cluj-Napoca, Romania; (E.G.); (G.S.)
- Institute for Research-Development-Innovation in Applied Natural Sciences, Babeș-Bolyai University, 30 Fântânele St., 400294 Cluj-Napoca, Romania
| | - Michael G. Klein
- Department of Entomology, The Ohio State University, 1680 Madison Ave., Wooster, OH 44691, USA;
| | - Zsuzsanna Koncz
- Max-Planck Institut für Pflanzenzüchtungsforschung, Carl-von-Linné-Weg 10, D-50829 Köln, Germany;
| | | | - László Ötvös
- OLPE, LLC, Audubon, PA 19403-1965, USA;
- Institute of Medical Microbiology, Semmelweis University, H-1085 Budapest, Hungary
- Arrevus, Inc., Raleigh, NC 27612, USA
| | - Gyöngyi Székely
- Hungarian Department of Biology and Ecology, Faculty of Biology and Geology, Babeș-Bolyai University, 5-7 Clinicilor St., 400006 Cluj-Napoca, Romania; (E.G.); (G.S.)
- Institute for Research-Development-Innovation in Applied Natural Sciences, Babeș-Bolyai University, 30 Fântânele St., 400294 Cluj-Napoca, Romania
- Centre for Systems Biology, Biodiversity and Bioresources, Babeș-Bolyai University, 5-7 Clinicilor St., 400006 Cluj-Napoca, Romania
| | - Dávid Vozik
- Research Institute on Bioengineering, Membrane Technology and Energetics, Faculty of Engineering, University of Veszprem, H-8200 Veszprém, Hungary; or or
| | - László Makrai
- Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, P.O. Box 22, H-1581 Budapest, Hungary;
- Correspondence: or (A.F.); (L.M.); Tel.: +36-(30)-490-9294 (A.F.); +36-(30)-271-2513 (L.M.)
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183
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Candida albicans Genetic Background Influences Mean and Heterogeneity of Drug Responses and Genome Stability during Evolution in Fluconazole. mSphere 2020; 5:5/3/e00480-20. [PMID: 32581072 PMCID: PMC7316494 DOI: 10.1128/msphere.00480-20] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Antimicrobial resistance is an evolutionary phenomenon with clinical implications. We tested how replicates from diverse strains of Candida albicans, a prevalent human fungal pathogen, evolve in the commonly prescribed antifungal drug fluconazole. Replicates on average increased in fitness in the level of drug they were evolved to, with the least fit parental strains improving the most. Very few replicates increased resistance above the drug level they were evolved in. Notably, many replicates increased in genome size and changed in drug tolerance (a drug response where a subpopulation of cells grow slowly in high levels of drug), and variability among replicates in fitness, tolerance, and genome size was higher in strains that initially were more sensitive to the drug. Genetic background influenced the average degree of adaptation and the evolved variability of many phenotypes, highlighting that different strains from the same species may respond and adapt very differently during adaptation. The importance of within-species diversity in determining the evolutionary potential of a population to evolve drug resistance or tolerance is not well understood, including in eukaryotic pathogens. To examine the influence of genetic background, we evolved replicates of 20 different clinical isolates of Candida albicans, a human fungal pathogen, in fluconazole, the commonly used antifungal drug. The isolates hailed from the major C. albicans clades and had different initial levels of drug resistance and tolerance to the drug. The majority of replicates rapidly increased in fitness in the evolutionary environment, with the degree of improvement inversely correlated with parental strain fitness in the drug. Improvement was largely restricted to up to the evolutionary level of drug: only 4% of the evolved replicates increased resistance (MIC) above the evolutionary level of drug. Prevalent changes were altered levels of drug tolerance (slow growth of a subpopulation of cells at drug concentrations above the MIC) and increased diversity of genome size. The prevalence and predominant direction of these changes differed in a strain-specific manner, but neither correlated directly with parental fitness or improvement in fitness. Rather, low parental strain fitness was correlated with high levels of heterogeneity in fitness, tolerance, and genome size among evolved replicates. Thus, parental strain background is an important determinant in mean improvement to the evolutionary environment as well as the diversity of evolved phenotypes, and the range of possible responses of a pathogen to an antimicrobial drug cannot be captured by in-depth study of a single strain background. IMPORTANCE Antimicrobial resistance is an evolutionary phenomenon with clinical implications. We tested how replicates from diverse strains of Candida albicans, a prevalent human fungal pathogen, evolve in the commonly prescribed antifungal drug fluconazole. Replicates on average increased in fitness in the level of drug they were evolved to, with the least fit parental strains improving the most. Very few replicates increased resistance above the drug level they were evolved in. Notably, many replicates increased in genome size and changed in drug tolerance (a drug response where a subpopulation of cells grow slowly in high levels of drug), and variability among replicates in fitness, tolerance, and genome size was higher in strains that initially were more sensitive to the drug. Genetic background influenced the average degree of adaptation and the evolved variability of many phenotypes, highlighting that different strains from the same species may respond and adapt very differently during adaptation.
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184
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Zhang D, Hu Y, Zhu Q, Huang J, Chen Y. Proteomic interrogation of antibiotic resistance and persistence in Escherichia coli - progress and potential for medical research. Expert Rev Proteomics 2020; 17:393-409. [PMID: 32567419 DOI: 10.1080/14789450.2020.1784731] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Introduction Escherichia coli strains possess two survival strategies to endure lethal antibiotic exposure including antibiotic resistance and persistence, in which persistence can contribute to the emergence of antibiotic resistance and increasing the risk of multidrug resistance. Using high-throughput proteomics for the comprehensive understanding of mechanisms of antibiotic resistance and persistence is an effective strategy for development of target-based anti-bacterial therapies. Areas covered In this review, we summarize a comprehensive proteomic perspective of antibiotic resistance and persistence in E. coli, and overview of anti-antibiotic resistance and anti-persister molecules and strategies for the development of potential therapies. Expert opinion Proteomics allows us to globally identify the critical proteins and pathways involved in antibiotic resistance and persistence. Advancements in methodologies of proteomics and multi-omic strategies are required to overcome the limitations of proteomics and better understand mechanisms of antibiotic resistance and persistence in E. coli, and to open the possibility for identification of new targets for alternative strategies in therapeutics.
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Affiliation(s)
- Danfeng Zhang
- School of Biological Science and Biotechnology, Minnan Normal University , Zhangzhou, China
| | - Yuanqing Hu
- School of Biological Science and Biotechnology, Minnan Normal University , Zhangzhou, China
| | - Qiuqiang Zhu
- School of Biological Science and Biotechnology, Minnan Normal University , Zhangzhou, China
| | - Jiafu Huang
- School of Biological Science and Biotechnology, Minnan Normal University , Zhangzhou, China.,Engineering Technological Center of Mushroom Industry , Zhangzhou, China
| | - Yiyun Chen
- School of Biological Science and Biotechnology, Minnan Normal University , Zhangzhou, China
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185
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Label-Free Electrochemical Microfluidic Chip for the Antimicrobial Susceptibility Testing. Antibiotics (Basel) 2020; 9:antibiotics9060348. [PMID: 32575678 PMCID: PMC7344617 DOI: 10.3390/antibiotics9060348] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 06/17/2020] [Accepted: 06/17/2020] [Indexed: 01/15/2023] Open
Abstract
The emergence and spread of antibiotic-resistant bacteria is a global threat to human health. An accurate antibiotic susceptibility test (AST) before initiating the treatment is paramount in the treatment and bacterial resistance control. However, the current AST methods either are complex, use chemical and biological labels, lack multiplexing, are expensive, or are too slow to be used for routine screening. The primary objective of the current study is to develop an automated electrochemical microfluidic chip (EMC) for simple and rapid AST. The microfluidic channels and gold microelectrodes were designed for the automation of antibiotic mixing and distribution in multiple test chambers and for electrical signal measurements. The designed chip was tested for AST with E. coli samples, and the results were compared with conventional broth microdilution. The presented EMC provided rapid bacterial count and AST in 170 and 150 min, respectively, while the conventional broth microdilution evaluates in 450 and 240 min, respectively. The rapid AST capability of the EMC was further demonstrated with the artificial urine samples, and the results were obtained in 270 min, which was 90 min faster than the broth microdilution method. Additionally, the minimum inhibitory concentration (MIC) was evaluated on the EMC and compared with the results from an AlamarBlue assay. The experimental results indicate the sensitivity of the chip, minimum loss of antibiotics, and eventually, reduction in the evolution of antibiotic resistance. Cumulatively, we have developed an automated, label-free, economical, rapid, robust, and user-friendly EMC for the evaluation of AST in urine samples.
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186
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Ferreira MA, Pereira ML, Dos Santos KV. Drug-induced tolerance: the effects of antibiotic pre-exposure in Stenotrophomonas maltophilia. Future Microbiol 2020; 15:497-508. [PMID: 32478618 DOI: 10.2217/fmb-2019-0253] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Aim: To investigate if the prior use of nontargeted antibiotics induces cross-tolerance in Stenotrophomonas maltophilia. Methods: Antibiotic induction was performed to evaluate daptomycin and vancomycin as possible tolerance-inducing drugs measured by minimum bactericidal concentration/minimum inhibitory concentration (MIC) ratio, adapted disk-diffusion tests and time-kill curves. Results: After antibiotic exposure, three potentially tolerant strains were isolated, maintaining the same MIC value of levofloxacin, with minimum bactericidal concentration/MIC ratio slightly higher than the parental. In the adapted disk-diffusion test, one strain (D25) showed high tolerance level for levofloxacin, ceftazidime and ticarcillin-clavulanate. In time-kill activity of levofloxacin, D25 presented a subpopulation of persisters with survival rate higher (1.6-fold) than the parental. Conclusion: Previous exposure of S. maltophilia to daptomycin can induce cross-tolerance to ceftazidime and ticarcillin-clavulanate and cross-persistence to levofloxacin.
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Affiliation(s)
- Mariana Am Ferreira
- Department of Pathology, Health Sciences Center, Universidade Federal do Espírito Santo (UFES), Av. Marechal Campos, 1468, 29040-090 Vitória, Espírito Santo, Brazil
| | - Maria Ls Pereira
- Department of Pathology, Health Sciences Center, Universidade Federal do Espírito Santo (UFES), Av. Marechal Campos, 1468, 29040-090 Vitória, Espírito Santo, Brazil
| | - Kênia V Dos Santos
- Department of Pathology, Health Sciences Center, Universidade Federal do Espírito Santo (UFES), Av. Marechal Campos, 1468, 29040-090 Vitória, Espírito Santo, Brazil
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187
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Dhar R. Role of Mitochondria in Generation of Phenotypic Heterogeneity in Yeast. J Indian Inst Sci 2020. [DOI: 10.1007/s41745-020-00176-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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188
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Lopatkin AJ, Collins JJ. Predictive biology: modelling, understanding and harnessing microbial complexity. Nat Rev Microbiol 2020; 18:507-520. [DOI: 10.1038/s41579-020-0372-5] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/15/2020] [Indexed: 12/11/2022]
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189
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Evolutionary causes and consequences of bacterial antibiotic persistence. Nat Rev Microbiol 2020; 18:479-490. [PMID: 32461608 DOI: 10.1038/s41579-020-0378-z] [Citation(s) in RCA: 97] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/17/2020] [Indexed: 12/12/2022]
Abstract
Antibiotic treatment failure is of growing concern. Genetically encoded resistance is key in driving this process. However, there is increasing evidence that bacterial antibiotic persistence, a non-genetically encoded and reversible loss of antibiotic susceptibility, contributes to treatment failure and emergence of resistant strains as well. In this Review, we discuss the evolutionary forces that may drive the selection for antibiotic persistence. We review how some aspects of antibiotic persistence have been directly selected for whereas others result from indirect selection in disparate ecological contexts. We then discuss the consequences of antibiotic persistence on pathogen evolution. Persisters can facilitate the evolution of antibiotic resistance and virulence. Finally, we propose practical means to prevent persister formation and how this may help to slow down the evolution of virulence and resistance in pathogens.
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190
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Mutations in ArgS Arginine-tRNA Synthetase Confer Additional Antibiotic Tolerance Protection to Extended-Spectrum-β-Lactamase-Producing Burkholderia thailandensis. Antimicrob Agents Chemother 2020; 64:AAC.02252-19. [PMID: 32205346 DOI: 10.1128/aac.02252-19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 03/03/2020] [Indexed: 11/20/2022] Open
Abstract
Highly conserved PenI-type class A β-lactamase in pathogenic members of Burkholderia species can evolve to extended-spectrum β-lactamase (ESBL), which exhibits hydrolytic activity toward third-generation cephalosporins, while losing its activity toward the original penicillin substrates. We describe three single-amino-acid-substitution mutations in the ArgS arginine-tRNA synthetase that confer extra antibiotic tolerance protection to ESBL-producing Burkholderia thailandensis This pathway can be exploited to evade antibiotic tolerance induction in developing therapeutic measures against Burkholderia species, targeting their essential aminoacyl-tRNA synthetases.
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191
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Teimouri H, Kolomeisky AB. Theoretical investigation of stochastic clearance of bacteria: first-passage analysis. J R Soc Interface 2020; 16:20180765. [PMID: 30890051 DOI: 10.1098/rsif.2018.0765] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Understanding mechanisms of bacterial eradication is critically important for overcoming failures of antibiotic treatments. Current studies suggest that the clearance of large bacterial populations proceeds deterministically, while for smaller populations, the stochastic effects become more relevant. Here, we develop a theoretical approach to investigate the bacterial population dynamics under the effect of antibiotic drugs using a method of first-passage processes. It allows us to explicitly evaluate the most important characteristics of bacterial clearance dynamics such as extinction probabilities and extinction times. The new meaning of minimal inhibitory concentrations for stochastic clearance of bacterial populations is also discussed. In addition, we investigate the effect of fluctuations in population growth rates on the dynamics of bacterial eradication. It is found that extinction probabilities and extinction times generally do not correlate with each other when random fluctuations in the growth rates are taking place. Unexpectedly, for a significant range of parameters, the extinction times increase due to these fluctuations, indicating a slowing in the bacterial clearance dynamics. It is argued that this might be one of the initial steps in the pathway for the development of antibiotic resistance. Furthermore, it is suggested that extinction times is a convenient measure of bacterial tolerance.
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Affiliation(s)
- Hamid Teimouri
- 1 Department of Chemistry, Rice University , Houston, TX , USA.,3 Center for Theoretical Biological Physics, Rice University , Houston, TX , USA
| | - Anatoly B Kolomeisky
- 1 Department of Chemistry, Rice University , Houston, TX , USA.,2 Department of Chemical and Biomolecular Engineering, Rice University , Houston, TX , USA.,3 Center for Theoretical Biological Physics, Rice University , Houston, TX , USA
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192
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Liu J, Gefen O, Ronin I, Bar-Meir M, Balaban NQ. Effect of tolerance on the evolution of antibiotic resistance under drug combinations. Science 2020; 367:200-204. [PMID: 31919223 DOI: 10.1126/science.aay3041] [Citation(s) in RCA: 242] [Impact Index Per Article: 60.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 11/20/2019] [Indexed: 12/21/2022]
Abstract
Drug combinations are widely used in clinical practice to prevent the evolution of resistance. However, little is known about the effect of tolerance, a different mode of survival, on the efficacy of drug combinations for preventing the evolution of resistance. In this work, we monitored Staphylococcus aureus strains evolving in patients under treatment. We detected the rapid emergence of tolerance mutations, followed by the emergence of resistance, despite the combination treatment. Evolution experiments on the clinical strains in vitro revealed a new way by which tolerance promotes the evolution of resistance under combination treatments. Further experiments under different antibiotic classes reveal the generality of the effect. We conclude that tolerance is an important factor to consider in designing combination treatments that prevent the evolution of resistance.
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Affiliation(s)
- Jiafeng Liu
- Racah Institute of Physics, Edmond J. Safra Campus, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Orit Gefen
- Racah Institute of Physics, Edmond J. Safra Campus, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Irine Ronin
- Racah Institute of Physics, Edmond J. Safra Campus, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Maskit Bar-Meir
- Pediatrics and Infectious Diseases Division, Shaare Zedek Medical Center, Jerusalem, Israel. .,Faculty of Medicine, The Hebrew University, Jerusalem, Israel
| | - Nathalie Q Balaban
- Racah Institute of Physics, Edmond J. Safra Campus, The Hebrew University of Jerusalem, Jerusalem, Israel.
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193
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Abstract
Antiviral drugs have traditionally been developed by directly targeting essential viral components. However, this strategy often fails due to the rapid generation of drug-resistant viruses. Recent genome-wide approaches, such as those employing small interfering RNA (siRNA) or clustered regularly interspaced short palindromic repeats (CRISPR) or those using small molecule chemical inhibitors targeting the cellular "kinome," have been used successfully to identify cellular factors that can support virus replication. Since some of these cellular factors are critical for virus replication, but are dispensable for the host, they can serve as novel targets for antiviral drug development. In addition, potentiation of immune responses, regulation of cytokine storms, and modulation of epigenetic changes upon virus infections are also feasible approaches to control infections. Because it is less likely that viruses will mutate to replace missing cellular functions, the chance of generating drug-resistant mutants with host-targeted inhibitor approaches is minimized. However, drug resistance against some host-directed agents can, in fact, occur under certain circumstances, such as long-term selection pressure of a host-directed antiviral agent that can allow the virus the opportunity to adapt to use an alternate host factor or to alter its affinity toward the target that confers resistance. This review describes novel approaches for antiviral drug development with a focus on host-directed therapies and the potential mechanisms that may account for the acquisition of antiviral drug resistance against host-directed agents.
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194
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Cell Wall Composition Heterogeneity between Single Cells in Aspergillus fumigatus Leads to Heterogeneous Behavior during Antifungal Treatment and Phagocytosis. mBio 2020; 11:mBio.03015-19. [PMID: 32398317 PMCID: PMC7218287 DOI: 10.1128/mbio.03015-19] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The fungus Aspergillus fumigatus can cause invasive lung diseases in immunocompromised patients resulting in high mortality. Treatment using antifungal compounds is often unsuccessful. Average population measurements hide what is happening at the individual cell level. We set out to test what impact individual differences between the cell walls of fungal conidia have on their behavior. We show that a population of cells having the same genetic background gives rise to subpopulations of cells that exhibit distinct behavior (phenotypic heterogeneity). This cell heterogeneity is dependent on the strain type, gene deletions, cell age, and environmental conditions. By looking at the individual cell level, we discovered subpopulations of cells that show differential fitness during antifungal treatment and uptake by immune cells. Aspergillus fumigatus can cause a variety of lung diseases in immunocompromised patients, including life-threatening invasive aspergillosis. There are only three main classes of antifungal drugs currently used to treat aspergillosis, and antifungal resistance is increasing. Experimental results in fungal biology research are usually obtained as average measurements across whole populations while ignoring what is happening at the single cell level. In this study, we show that conidia with the same genetic background in the same cell population at a similar developmental stage show heterogeneity in their cell wall labeling at the single cell level. We present a rigorous statistical method, newly applied to quantify the level of cell heterogeneity, which allows for direct comparison of the heterogeneity observed between treatments. We show the extent of cell wall labeling heterogeneity in dormant conidia and how the level of heterogeneity changes during germination. The degree of heterogeneity is influenced by deletions of cell wall synthesizing genes and environmental conditions, including medium composition, method of inoculation, age of conidia, and the presence of antifungals. This heterogeneity results in subpopulations of germinating conidia with heterogeneous fitness to the antifungal caspofungin, which targets cell wall synthesis and heterogeneous sensitivity of dormant conidia to phagocytosis by macrophages.
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195
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Windels EM, Van den Bergh B, Michiels J. Bacteria under antibiotic attack: Different strategies for evolutionary adaptation. PLoS Pathog 2020; 16:e1008431. [PMID: 32379814 PMCID: PMC7205213 DOI: 10.1371/journal.ppat.1008431] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Bacteria are well known for their extremely high adaptability in stressful environments. The clinical relevance of this property is clearly illustrated by the ever-decreasing efficacy of antibiotic therapies. Frequent exposures to antibiotics favor bacterial strains that have acquired mechanisms to overcome drug inhibition and lethality. Many strains, including life-threatening pathogens, exhibit increased antibiotic resistance or tolerance, which considerably complicates clinical practice. Alarmingly, recent studies show that in addition to resistance, tolerance levels of bacterial populations are extremely flexible in an evolutionary context. Here, we summarize laboratory studies providing insight in the evolution of resistance and tolerance and shed light on how the treatment conditions could affect the direction of bacterial evolution under antibiotic stress.
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Affiliation(s)
- Etthel M. Windels
- VIB Center for Microbiology, Flanders Institute for Biotechnology, Leuven, Belgium
- Centre of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
| | - Bram Van den Bergh
- VIB Center for Microbiology, Flanders Institute for Biotechnology, Leuven, Belgium
- Centre of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
| | - Jan Michiels
- VIB Center for Microbiology, Flanders Institute for Biotechnology, Leuven, Belgium
- Centre of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
- * E-mail:
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196
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Gollan B, Grabe G, Michaux C, Helaine S. Bacterial Persisters and Infection: Past, Present, and Progressing. Annu Rev Microbiol 2020; 73:359-385. [PMID: 31500532 DOI: 10.1146/annurev-micro-020518-115650] [Citation(s) in RCA: 148] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Persisters are nongrowing, transiently antibiotic-tolerant bacteria within a clonal population of otherwise susceptible cells. Their formation is triggered by environmental cues and involves the main bacterial stress response pathways that allow persisters to survive many harsh conditions, including antibiotic exposure. During infection, bacterial pathogens are exposed to a vast array of stresses in the host and form nongrowing persisters that survive both antibiotics and host immune responses, thereby most likely contributing to the relapse of many infections. While antibiotic persisters have been extensively studied over the last decade, the bulk of the work has focused on how these bacteria survive exposure to drugs in vitro. The ability of persisters to survive their interaction with a host is important yet underinvestigated. In order to tackle the problem of persistence of infections that contribute to the worldwide antibiotic resistance crisis, efforts should be made by scientific communities to understand and merge these two fields of research: antibiotic persisters and host-pathogen interactions. Here we give an overview of the history of the field of antibiotic persistence, report evidence for the importance of persisters in infection, and highlight studies that bridge the two areas.
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Affiliation(s)
- Bridget Gollan
- Section of Microbiology, Medical Research Council Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, United Kingdom; , , ,
| | - Grzegorz Grabe
- Section of Microbiology, Medical Research Council Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, United Kingdom; , , ,
| | - Charlotte Michaux
- Section of Microbiology, Medical Research Council Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, United Kingdom; , , ,
| | - Sophie Helaine
- Section of Microbiology, Medical Research Council Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, United Kingdom; , , ,
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197
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Kuehl R, Morata L, Meylan S, Mensa J, Soriano A. When antibiotics fail: a clinical and microbiological perspective on antibiotic tolerance and persistence of Staphylococcus aureus. J Antimicrob Chemother 2020; 75:1071-1086. [PMID: 32016348 DOI: 10.1093/jac/dkz559] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Staphylococcus aureus is a major human pathogen causing a vast array of infections with significant mortality. Its versatile physiology enables it to adapt to various environments. Specific physiological changes are thought to underlie the frequent failure of antimicrobial therapy despite susceptibility in standard microbiological assays. Bacteria capable of surviving high antibiotic concentrations despite having a genetically susceptible background are described as 'antibiotic tolerant'. In this review, we put current knowledge on environmental triggers and molecular mechanisms of increased antibiotic survival of S. aureus into its clinical context. We discuss animal and clinical evidence of its significance and outline strategies to overcome infections with antibiotic-tolerant S. aureus.
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Affiliation(s)
- Richard Kuehl
- Service of Infectious Diseases, Hospital Clinic of Barcelona, University of Barcelona, IDIBAPS, Barcelona, Spain
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Basel, Basel, Switzerland
| | - Laura Morata
- Service of Infectious Diseases, Hospital Clinic of Barcelona, University of Barcelona, IDIBAPS, Barcelona, Spain
| | - Sylvain Meylan
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Basel, Basel, Switzerland
- Division de Maladies Infectieuses, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - Josep Mensa
- Service of Infectious Diseases, Hospital Clinic of Barcelona, University of Barcelona, IDIBAPS, Barcelona, Spain
| | - Alex Soriano
- Service of Infectious Diseases, Hospital Clinic of Barcelona, University of Barcelona, IDIBAPS, Barcelona, Spain
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198
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Environmental drivers of metabolic heterogeneity in clonal microbial populations. Curr Opin Biotechnol 2020; 62:202-211. [DOI: 10.1016/j.copbio.2019.11.018] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 11/15/2019] [Accepted: 11/22/2019] [Indexed: 02/06/2023]
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199
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Balaban NQ, Helaine S, Lewis K, Ackermann M, Aldridge B, Andersson DI, Brynildsen MP, Bumann D, Camilli A, Collins JJ, Dehio C, Fortune S, Ghigo JM, Hardt WD, Harms A, Heinemann M, Hung DT, Jenal U, Levin BR, Michiels J, Storz G, Tan MW, Tenson T, Van Melderen L, Zinkernagel A. Definitions and guidelines for research on antibiotic persistence. Nat Rev Microbiol 2020; 17:441-448. [PMID: 30980069 PMCID: PMC7136161 DOI: 10.1038/s41579-019-0196-3] [Citation(s) in RCA: 636] [Impact Index Per Article: 159.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Increasing concerns about the rising rates of antibiotic therapy failure and advances in single-cell analyses have inspired a surge of research into antibiotic persistence. Bacterial persister cells represent a subpopulation of cells that can survive intensive antibiotic treatment without being resistant. Several approaches have emerged to define and measure persistence, and it is now time to agree on the basic definition of persistence and its relation to the other mechanisms by which bacteria survive exposure to bactericidal antibiotic treatments, such as antibiotic resistance, heteroresistance or tolerance. In this Consensus Statement, we provide definitions of persistence phenomena, distinguish between triggered and spontaneous persistence and provide a guide to measuring persistence. Antibiotic persistence is not only an interesting example of non-genetic single-cell heterogeneity, it may also have a role in the failure of antibiotic treatments. Therefore, it is our hope that the guidelines outlined in this article will pave the way for better characterization of antibiotic persistence and for understanding its relevance to clinical outcomes. Antibiotic persistence contributes to the survival of bacteria during antibiotic treatment. In this Consensus Statement, scientists working on the response of bacteria to antibiotics define antibiotic persistence and provide practical guidance on how to study bacterial persisters.
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Affiliation(s)
| | - Sophie Helaine
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, UK
| | - Kim Lewis
- Department of Biology, Northeastern University, Boston, MA, USA
| | - Martin Ackermann
- Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, Zurich, Switzerland.,Department of Environmental Microbiology, Eawag, Dubendorf, Switzerland
| | - Bree Aldridge
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, USA
| | - Dan I Andersson
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Mark P Brynildsen
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, USA
| | - Dirk Bumann
- Focal Area Infection Biology, Biozentrum of the University of Basel, Basel, Switzerland
| | - Andrew Camilli
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, USA
| | - James J Collins
- Institute for Medical Engineering & Science, Department of Biological Engineering, and Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, USA.,Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA.,Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Christoph Dehio
- Focal Area Infection Biology, Biozentrum of the University of Basel, Basel, Switzerland
| | - Sarah Fortune
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Jean-Marc Ghigo
- Institut Pasteur, Genetics of Biofilms Laboratory, Paris, France
| | | | - Alexander Harms
- Focal Area Infection Biology, Biozentrum of the University of Basel, Basel, Switzerland
| | - Matthias Heinemann
- Molecular Systems Biology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, Netherlands
| | | | - Urs Jenal
- Focal Area Infection Biology, Biozentrum of the University of Basel, Basel, Switzerland
| | - Bruce R Levin
- Department of Biology, Emory University, Atlanta, GA, USA
| | - Jan Michiels
- Center for Microbiology, KU Leuven-University of Leuven, Leuven, Belgium
| | - Gisela Storz
- Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD, USA
| | - Man-Wah Tan
- Infectious Diseases Department, Genentech, South San Francisco, CA, USA
| | - Tanel Tenson
- Institute of Technology, University of Tartu, Tartu, Estonia
| | | | - Annelies Zinkernagel
- Division of Infectious Diseases, University Hospital Zurich, University of Zurich, Zurich, Switzerland
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200
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Galera-Laporta L, Garcia-Ojalvo J. Antithetic population response to antibiotics in a polybacterial community. SCIENCE ADVANCES 2020; 6:eaaz5108. [PMID: 32181369 PMCID: PMC7060062 DOI: 10.1126/sciadv.aaz5108] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Accepted: 12/05/2019] [Indexed: 05/31/2023]
Abstract
Much is known about the effects of antibiotics on isolated bacterial species, but their influence on polybacterial communities is less understood. Here, we study the joint response of a mixed community of nonresistant Bacillus subtilis and Escherichia coli bacteria to moderate concentrations of the β-lactam antibiotic ampicillin. We show that when the two organisms coexist, their population response to the antibiotic is opposite to that in isolation: Whereas in monoculture B. subtilis is tolerant and E. coli is sensitive to ampicillin, in coculture it is E. coli who can proliferate in the presence of the antibiotic, while B. subtilis cannot. This antithetic behavior is predicted by a mathematical model constrained only by the responses of the two species in isolation. Our results thus show that the collective response of mixed bacterial ecosystems to antibiotics can run counter to what single-species potency studies tell us about their efficacy.
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