1
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Geraldes C, Tavares L, Gil S, Oliveira M. Antibiotic heteroresistance and persistence: an additional aid in hospital acquired infections by Enterococcus spp.? Future Microbiol 2024:1-12. [PMID: 39229839 DOI: 10.1080/17460913.2024.2393003] [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: 05/02/2024] [Accepted: 08/13/2024] [Indexed: 09/05/2024] Open
Abstract
Enterococcus, particularly E. faecium and E. faecalis, are responsible for many hospital-acquired infections. With their intrinsic antibiotic resistance and ability to form biofilms, enterococcal infections are already challenging to manage. However, when heterogenous populations are present, such as those exhibiting heteroresistance and persistence, the complexity of these infections increases exponentially not only due to their treatment but also due to their difficult diagnosis. In this study, we provide a summary of the current understanding of both heteroresistance and persistence in terms of mechanisms, diagnosis and treatment and subsequently review recent literature pertaining to these susceptibility types specifically in enterococci.
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Affiliation(s)
- Catarina Geraldes
- CIISA - Centre for Interdisciplinary Research in Animal Health, Faculty of Veterinary Medicine, University of Lisbon, Lisbon, Portugal
- AL4AnimalS - Associate Laboratory for Animal & Veterinary Sciences, Faculty of Veterinary Medicine, University of Lisbon, Lisbon, Portugal
| | - Luís Tavares
- CIISA - Centre for Interdisciplinary Research in Animal Health, Faculty of Veterinary Medicine, University of Lisbon, Lisbon, Portugal
- AL4AnimalS - Associate Laboratory for Animal & Veterinary Sciences, Faculty of Veterinary Medicine, University of Lisbon, Lisbon, Portugal
| | - Solange Gil
- CIISA - Centre for Interdisciplinary Research in Animal Health, Faculty of Veterinary Medicine, University of Lisbon, Lisbon, Portugal
- AL4AnimalS - Associate Laboratory for Animal & Veterinary Sciences, Faculty of Veterinary Medicine, University of Lisbon, Lisbon, Portugal
- BICU - Biological Isolation & Containment Unit, Faculty of Veterinary Medicine, University of Lisbon, Lisbon, Portugal
| | - Manuela Oliveira
- CIISA - Centre for Interdisciplinary Research in Animal Health, Faculty of Veterinary Medicine, University of Lisbon, Lisbon, Portugal
- AL4AnimalS - Associate Laboratory for Animal & Veterinary Sciences, Faculty of Veterinary Medicine, University of Lisbon, Lisbon, Portugal
- cE3c - Centre for Ecology, Evolution & Environmental Changes & CHANGE-Global Change & Sustainability Institute, Faculty of Sciences, University of Lisbon, Lisbon, Portugal
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2
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Kim YJ, Choi HS, Park DH. Persistence and viable but non-culturable state induced by streptomycin in Erwinia amylovora. Front Microbiol 2024; 15:1346300. [PMID: 38450169 PMCID: PMC10914980 DOI: 10.3389/fmicb.2024.1346300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 02/08/2024] [Indexed: 03/08/2024] Open
Abstract
Persister cell and viable but non-culturable (VBNC) state of bacteria are survival strategies against antibiotics and various environmental stresses, respectively, but they tend to be ignored in agriculture fields, even though bacteria can regain their abilities to survive and produce disease once those stresses disappear. This study was carried out to determine whether persister cell and VBNC state in Erwinia amylovora are present after exposures to streptomycin, the length of their persistence, and the steps needed to decrease the inoculum. Persister cells were observed using biphasic killed growth curve for 4-8 h when the late stationary phase cells of E. amylovora were cultured in liquid medium containing streptomycin. This state was maintained for up to 12 h based on the colony forming units (CFUs) of the colonies that grew on the mannitol glutamate yeast extract (MGY) medium after streptomycin was removed. The CFUs on the MGY medium were lower than the total count determined using the LIVE/DEAD Kit, suggesting that persister cells and VBNC state might co-exist for up to 12 h after exposure to streptomycin. However, after 12 h, E. amylovora cells did not continue to grow on the medium for 9 days, suggesting that they entered a VBNC state at that time and remained in a persistent state. In addition, based on the Redox Sensor Green staining method, the presence of both states was confirmed for up to 12 h, and only then did the VBNC state became apparent. Furthermore, persister cells were observed for up to 24 h, and damaged cells reduced when E. amylovora cells were culture in distilled water with streptomycin, indicating that the uptake of lower nutrients in E. amylovora led to prolonged persister cells and VBNC state, which are more likely to survive after streptomycin treatments. The addition of sucrose and oxytetracycline to distilled water containing streptomycin reduced persister cells than other sources did. Thus, to inhibit the spread of fire blight, management techniques must consider the hazards of using streptomycin treatments that induce dormancy, such as persister cells and VBNC state, beyond the development of resistant strain.
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Affiliation(s)
- Yeon Ju Kim
- Interdisciplinary Program in Smart Agriculture, Kangwon National University, Chuncheon-si, Republic of Korea
| | - Hyun Seo Choi
- Interdisciplinary Program in Smart Agriculture, Kangwon National University, Chuncheon-si, Republic of Korea
| | - Duck Hwan Park
- Interdisciplinary Program in Smart Agriculture, Kangwon National University, Chuncheon-si, Republic of Korea
- Plant Medicine Program, Division of Bioresource Sciences, College of Agriculture and Life Sciences, Kangwon National University, Chuncheon-si, Republic of Korea
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3
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Bollen C, Louwagie E, Verstraeten N, Michiels J, Ruelens P. Environmental, mechanistic and evolutionary landscape of antibiotic persistence. EMBO Rep 2023; 24:e57309. [PMID: 37395716 PMCID: PMC10398667 DOI: 10.15252/embr.202357309] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 06/07/2023] [Accepted: 06/16/2023] [Indexed: 07/04/2023] Open
Abstract
Recalcitrant infections pose a serious challenge by prolonging antibiotic therapies and contributing to the spread of antibiotic resistance, thereby threatening the successful treatment of bacterial infections. One potential contributing factor in persistent infections is antibiotic persistence, which involves the survival of transiently tolerant subpopulations of bacteria. This review summarizes the current understanding of antibiotic persistence, including its clinical significance and the environmental and evolutionary factors at play. Additionally, we discuss the emerging concept of persister regrowth and potential strategies to combat persister cells. Recent advances highlight the multifaceted nature of persistence, which is controlled by deterministic and stochastic elements and shaped by genetic and environmental factors. To translate in vitro findings to in vivo settings, it is crucial to include the heterogeneity and complexity of bacterial populations in natural environments. As researchers continue to gain a more holistic understanding of this phenomenon and develop effective treatments for persistent bacterial infections, the study of antibiotic persistence is likely to become increasingly complex.
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Affiliation(s)
- Celien Bollen
- Centre of Microbial and Plant GeneticsKU LeuvenLeuvenBelgium
- Center for Microbiology, VIBLeuvenBelgium
| | - Elen Louwagie
- Centre of Microbial and Plant GeneticsKU LeuvenLeuvenBelgium
- Center for Microbiology, VIBLeuvenBelgium
| | - Natalie Verstraeten
- Centre of Microbial and Plant GeneticsKU LeuvenLeuvenBelgium
- Center for Microbiology, VIBLeuvenBelgium
| | - Jan Michiels
- Centre of Microbial and Plant GeneticsKU LeuvenLeuvenBelgium
- Center for Microbiology, VIBLeuvenBelgium
| | - Philip Ruelens
- Centre of Microbial and Plant GeneticsKU LeuvenLeuvenBelgium
- Center for Microbiology, VIBLeuvenBelgium
- Laboratory of Socioecology and Social EvolutionKU LeuvenLeuvenBelgium
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4
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Lv B, Huang X, Lijia C, Ma Y, Bian M, Li Z, Duan J, Zhou F, Yang B, Qie X, Song Y, Wood TK, Fu X. Heat shock potentiates aminoglycosides against gram-negative bacteria by enhancing antibiotic uptake, protein aggregation, and ROS. Proc Natl Acad Sci U S A 2023; 120:e2217254120. [PMID: 36917671 PMCID: PMC10041086 DOI: 10.1073/pnas.2217254120] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 01/25/2023] [Indexed: 03/15/2023] Open
Abstract
The potentiation of antibiotics is a promising strategy for combatting antibiotic-resistant/tolerant bacteria. Herein, we report that a 5-min sublethal heat shock enhances the bactericidal actions of aminoglycoside antibiotics by six orders of magnitude against both exponential- and stationary-phase Escherichia coli. This combined treatment also effectively kills various E. coli persisters, E. coli clinical isolates, and numerous gram-negative but not gram-positive bacteria and enables aminoglycosides at 5% of minimum inhibitory concentrations to eradicate multidrug-resistant pathogens Acinetobacter baumannii and Klebsiella pneumoniae. Mechanistically, the potentiation is achieved comprehensively by heat shock-enhanced proton motive force that thus promotes the bacterial uptake of aminoglycosides, as well as by increasing irreversible protein aggregation and reactive oxygen species that further augment the downstream lethality of aminoglycosides. Consistently, protonophores, chemical chaperones, antioxidants, and anaerobic culturing abolish heat shock-enhanced aminoglycoside lethality. We also demonstrate as a proof of concept that infrared irradiation- or photothermal nanosphere-induced thermal treatments potentiate aminoglycoside killing of Pseudomonas aeruginosa in a mouse acute skin wound model. Our study advances the understanding of the mechanism of actions of aminoglycosides and demonstrates a high potential for thermal ablation in curing bacterial infections when combined with aminoglycosides.
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Affiliation(s)
- Boyan Lv
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, Key Laboratory of Optoelectronic Science and Technology for Medicine of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou City350117, China
| | - Xuebing Huang
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, Key Laboratory of Optoelectronic Science and Technology for Medicine of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou City350117, China
| | - Chenchen Lijia
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, Key Laboratory of Optoelectronic Science and Technology for Medicine of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou City350117, China
| | - Yuelong Ma
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, Key Laboratory of Optoelectronic Science and Technology for Medicine of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou City350117, China
| | - Mengmeng Bian
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, Key Laboratory of Optoelectronic Science and Technology for Medicine of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou City350117, China
| | - Zhongyan Li
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, Key Laboratory of Optoelectronic Science and Technology for Medicine of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou City350117, China
| | - Juan Duan
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fujian Medical University, Fuzhou City350122, China
| | - Fang Zhou
- Department of Pharmacy, Southern University of Science and Technology Hospital, Shenzhen City518055, China
| | - Bin Yang
- Department of Laboratory Medicine, The First Affiliated Hospital of Fujian Medical University, Fuzhou350122, China
| | - Xingwang Qie
- CAS Key Laboratory of Bio-Medical Diagnostics, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou215163, China
| | - Yizhi Song
- CAS Key Laboratory of Bio-Medical Diagnostics, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou215163, China
| | - Thomas K. Wood
- Department of Chemical Engineering, Pennsylvania State University, University Park, PA16802-4400
| | - Xinmiao Fu
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, Key Laboratory of Optoelectronic Science and Technology for Medicine of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou City350117, China
- Engineering Research Center of Industrial Microbiology of Ministry of Education, Fujian Normal University, Fuzhou City350117, China
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5
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Li Z, Sun F, Fu X, Chen Y. 5-Methylindole kills various bacterial pathogens and potentiates aminoglycoside against methicillin-resistant Staphylococcus aureus. PeerJ 2022; 10:e14010. [PMID: 36124131 PMCID: PMC9482361 DOI: 10.7717/peerj.14010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 08/15/2022] [Indexed: 01/19/2023] Open
Abstract
Antibiotic resistance of bacterial pathogens has become a severe threat to human health. To counteract antibiotic resistance, it is of significance to discover new antibiotics and also improve the efficacy of existing antibiotics. Here we show that 5-methylindole, a derivative of the interspecies signaling molecule indole, is able to directly kill various Gram-positive pathogens (e.g., Staphylococcus aureus and Enterococcus faecalis) and also Gram-negative ones (e.g., Escherichia coli and Pseudomonas aeruginosa), with 2-methylindole being less potent. Particularly, 5-methylindole can kill methicillin-resistant S. aureus, multidrug-resistant Klebsiella pneumoniae, Mycobacterium tuberculosis, and antibiotic-tolerant S. aureus persisters. Furthermore, 5-methylindole significantly potentiates aminoglycoside antibiotics, but not fluoroquinolones, killing of S. aureus. In addition, 5-iodoindole also potentiates aminoglycosides. Our findings open a new avenue to develop indole derivatives like 5-methylindole as antibacterial agents or adjuvants of aminoglycoside.
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Affiliation(s)
- Zhongyan Li
- Fujian Normal University, Fuzhou, Fujian, China
| | - Fengqi Sun
- Fujian Normal University, Fuzhou, Fujian, China
| | - Xinmiao Fu
- Fujian Normal University, Fuzhou, Fujian, China
| | - Yajuan Chen
- Fujian Normal University, Fuzhou, Fujian, China
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6
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Lv B, Zeng Y, Zhang H, Li Z, Xu Z, Wang Y, Gao Y, Chen Y, Fu X. Mechanosensitive Channels Mediate Hypoionic Shock-Induced Aminoglycoside Potentiation against Bacterial Persisters by Enhancing Antibiotic Uptake. Antimicrob Agents Chemother 2022; 66:e0112521. [PMID: 34902270 PMCID: PMC8846477 DOI: 10.1128/aac.01125-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 12/03/2021] [Indexed: 12/31/2022] Open
Abstract
Improving the efficacy of existing antibiotics is a promising strategy for combating antibiotic-resistant/tolerant bacterial pathogens that have become a severe threat to human health. We previously reported that aminoglycoside antibiotics could be dramatically potentiated against stationary-phase Escherichia coli cells under hypoionic shock conditions (i.e., treatment with ion-free solutions), but the underlying molecular mechanism remains unknown. Here, we show that mechanosensitive (MS) channels, a ubiquitous protein family sensing mechanical forces of cell membrane, mediate such hypoionic shock-induced aminoglycoside potentiation. Two-minute treatment under conditions of hypoionic shock (e.g., in pure water) greatly enhances the bactericidal effects of aminoglycosides against both spontaneous and triggered E. coli persisters, numerous strains of Gram-negative pathogens in vitro, and Pseudomonas aeruginosa in mice. Such potentiation is achieved by hypoionic shock-enhanced bacterial uptake of aminoglycosides and is linked to hypoionic shock-induced destabilization of the cytoplasmic membrane in E. coli. Genetic and biochemical analyses reveal that MscS-family channels directly and redundantly mediate aminoglycoside uptake upon hypoionic shock and thus potentiation, with MscL channel showing reduced effect. Molecular docking and site-directed mutagenesis analyses reveal a putative streptomycin-binding pocket in MscS, critical for streptomycin uptake and potentiation. These results suggest that hypoionic shock treatment destabilizes the cytoplasmic membrane and thus changes the membrane tension, which immediately activates MS channels that are able to effectively transport aminoglycosides into the cytoplasm for downstream killing. Our findings reveal the biological effects of hypoionic shock on bacteria and can help to develop novel adjuvants for aminoglycoside potentiation to combat bacterial pathogens via activating MS channels.
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Affiliation(s)
- Boyan Lv
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province, China
| | - Youhui Zeng
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province, China
| | - Huaidong Zhang
- Engineering Research Center of Industrial Microbiology of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province, China
| | - Zhongyan Li
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province, China
| | - Zhaorong Xu
- Fujian Burn Institute, Fujian Medical University Union Hospital, Fuzhou, Fujian Province, China
| | - Yan Wang
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province, China
| | - Yuanyuan Gao
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province, China
- Engineering Research Center of Industrial Microbiology of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province, China
| | - Yajuan Chen
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province, China
| | - Xinmiao Fu
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province, China
- Engineering Research Center of Industrial Microbiology of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province, China
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7
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Lv B, Bian M, Huang X, Sun F, Gao Y, Wang Y, Fu Y, Yang B, Fu X. n-Butanol Potentiates Subinhibitory Aminoglycosides against Bacterial Persisters and Multidrug-Resistant MRSA by Rapidly Enhancing Antibiotic Uptake. ACS Infect Dis 2022; 8:373-386. [PMID: 35100802 DOI: 10.1021/acsinfecdis.1c00559] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Potentiation of traditional antibiotics is of significance for combating antibiotic-resistant bacteria that have become a severe threat to human and animal health. Here, we report that 1 min co-treatment with n-butanol greatly and specifically enhances the bactericidal action of aminoglycosides by 5 orders of magnitude against stationary-phase Staphylococcus aureus cells, with n-propanol and isobutanol showing less potency. This combined treatment also rapidly kills various S. aureus persisters, methicillin-resistant S. aureus (MRSA) cells, and numerous Gram-positive and -negative pathogens including some clinically isolated multidrug-resistant pathogens (e.g., S. aureus, Staphylococcus epidermidis, and Enterococcus faecalis) in vitro, as well as S. aureus in mice. Mechanistically, the potentiation results from the actions of aminoglycosides on their conventional target ribosome rather than the antiseptic effect of n-butanol and is achieved by rapidly enhancing the bacterial uptake of aminoglycosides, while salts and inhibitors of proton motive force (e.g., CCCP) can diminish this uptake. Importantly, such n-butanol-enhanced antibiotic uptake even enables subinhibitory concentrations of aminoglycosides to rapidly kill both MRSA and conventional S. aureus cells. Given n-butanol is a non-metabolite in the pathogens we tested, our work may open avenues to develop a metabolite-independent strategy for aminoglycoside potentiation to rapidly eliminate antibiotic-resistant/tolerant pathogens, as well as for reducing the toxicity associated with aminoglycoside use.
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Affiliation(s)
- Boyan Lv
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province 350117, China
| | - Mengmeng Bian
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province 350117, China
| | - Xuebing Huang
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province 350117, China
| | - Fengqi Sun
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province 350117, China
| | - Yuanyuan Gao
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province 350117, China
| | - Yan Wang
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province 350117, China
| | - Yajuan Fu
- Biomedical Research Center of South China, Fujian Normal University, Fuzhou, Fujian Province 350117, China
| | - Bin Yang
- Department of Laboratory Medicine, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian Province 350117, China
| | - Xinmiao Fu
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province 350117, China
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8
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Urbaniec J, Xu Y, Hu Y, Hingley-Wilson S, McFadden J. Phenotypic heterogeneity in persisters: a novel 'hunker' theory of persistence. FEMS Microbiol Rev 2022; 46:fuab042. [PMID: 34355746 PMCID: PMC8767447 DOI: 10.1093/femsre/fuab042] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 08/04/2021] [Indexed: 12/11/2022] Open
Abstract
Persistence has been linked to treatment failure since its discovery over 70 years ago and understanding formation, nature and survival of this key antibiotic refractory subpopulation is crucial to enhancing treatment success and combatting the threat of antimicrobial resistance (AMR). The term 'persistence' is often used interchangeably with other terms such as tolerance or dormancy. In this review we focus on 'antibiotic persistence' which we broadly define as a feature of a subpopulation of bacterial cells that possesses the non-heritable character of surviving exposure to one or more antibiotics; and persisters as cells that possess this characteristic. We discuss novel molecular mechanisms involved in persister cell formation, as well as environmental factors which can contribute to increased antibiotic persistence in vivo, highlighting recent developments advanced by single-cell studies. We also aim to provide a comprehensive model of persistence, the 'hunker' theory which is grounded in intrinsic heterogeneity of bacterial populations and a myriad of 'hunkering down' mechanisms which can contribute to antibiotic survival of the persister subpopulation. Finally, we discuss antibiotic persistence as a 'stepping-stone' to AMR and stress the urgent need to develop effective anti-persister treatment regimes to treat this highly clinically relevant bacterial sub-population.
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Affiliation(s)
- J Urbaniec
- Department of Microbial Sciences and University of Surrey, Guildford, Surrey, GU27XH, UK
| | - Ye Xu
- Department of Microbial Sciences and University of Surrey, Guildford, Surrey, GU27XH, UK
| | - Y Hu
- Farnborough Sensonic limited, Farnborough road, GU14 7NA, UK
| | - S Hingley-Wilson
- Department of Microbial Sciences and University of Surrey, Guildford, Surrey, GU27XH, UK
| | - J McFadden
- Department of Microbial Sciences and University of Surrey, Guildford, Surrey, GU27XH, UK
- Quantum biology doctoral training centre, University of Surrey, Guildford, Surrey, GU27XH, UK
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9
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Combining Colistin with Furanone C-30 Rescues Colistin Resistance of Gram-Negative Bacteria in Vitro and in Vivo. Microbiol Spectr 2021; 9:e0123121. [PMID: 34730415 PMCID: PMC8567244 DOI: 10.1128/spectrum.01231-21] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The spread of multidrug-resistant (MDR) Gram-negative bacteria (GNB) has led to serious public health problems worldwide. Colistin, as a “last resort” for the treatment of MDR bacterial infections, has been used significantly in recent years and has led to the continuous emergence of colistin-resistant strains. In this study, we aimed to investigate the synergistic effect on the antimicrobial and antibiofilm activities of a colistin/furanone C-30 combination against colistin-resistant GNB in vitro and in vivo. According to antimicrobial resistance profiles, most of the colistin-resistant strains we collected showed MDR phenotypes. The checkerboard method and time-kill curve showed that the combination with furanone C-30 increases the antibacterial activity of colistin significantly. In addition, the furanone C-30/colistin combination can not only inhibit the formation of bacterial biofilm but also has a better eradication effect on preformed mature biofilms. The result of scanning electron microscopy (SEM) demonstrated that the furanone C-30/colistin combination led to a significant reduction in the number of cells in biofilms. Furthermore, furanone C-30 at 50 μg/ml did not cause any additional toxicity to RAW264.7 cells according to a cytotoxicity assay. In in vivo infection experiments, the furanone C-30/colistin combination increased the survival rate of infected Galleria mellonella larvae as well as decreased the microbial load in a mouse thigh infection model. The synergistic effect of the furanone C-30/colistin combination against colistin-resistant GNB is encouraging, and this work may shed light on a new therapeutic approach to combat colistin-resistant pathogens. IMPORTANCE Colistin is among the few antibiotics effective against multidrug-resistant Gram-negative bacteria (GNB) clinical isolates. However, colistin-resistant GNB strains have emerged in recent years. Therefore, the combination of colistin and nonantibacterial drugs has attracted much attention. In this study, the furanone C-30/colistin combination showed good antibacterial and antibiofilm activity in vitro and in vivo. In addition, increased membrane permeability leads to the synergistic effect of the furanone C-30/colistin combination. Because of the low cytotoxicity of furanone C-30, this combination has good application prospects in clinical anti-infective therapy. This finding might shed light on the discovery of combination therapy for infections caused by colistin-resistant GNB pathogens.
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10
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Huang P, Wang Z, Cai K, Wei L, Chu Y, Guo M, Fan E. Targeting Bacterial Membrane Proteins to Explore the Beneficial Effects of Natural Products: New Antibiotics against Drug Resistance. Curr Med Chem 2021; 29:2109-2126. [PMID: 34126882 DOI: 10.2174/0929867328666210614121222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 04/27/2021] [Accepted: 04/30/2021] [Indexed: 11/22/2022]
Abstract
Antibiotic resistance is currently a world health crisis that urges the development of new antibacterial substances. To this end, natural products, including flavonoids, alkaloids, terpenoids, steroids, peptides and organic acids that play a vital role in the development of medicines and thus constitute a rich source in clinical practices, provide an important source of drugs directly or for the screen of lead compounds for new antibiotic development. Because membrane proteins, which comprise more than 60% of the current clinical drug targets, play crucial roles in signal transduction, transport, bacterial pathogenicity and drug resistance, as well as immunogenicity, it is our aim to summarize those natural products with different structures that target bacterial membrane proteins, such as efflux pumps and enzymes, to provide an overview for the development of new antibiotics to deal with antibiotic resistance.
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Affiliation(s)
- Piying Huang
- State Key Laboratory of Medical Molecular Biology, Department of Microbiology and Parasitology, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
| | - Zhe Wang
- State Key Laboratory of Medical Molecular Biology, Department of Microbiology and Parasitology, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
| | - Kun Cai
- State Key Laboratory of Medical Molecular Biology, Department of Microbiology and Parasitology, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
| | - Liangwan Wei
- State Key Laboratory of Medical Molecular Biology, Department of Microbiology and Parasitology, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
| | - Yindi Chu
- State Key Laboratory of Medical Molecular Biology, Department of Microbiology and Parasitology, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
| | - Mingquan Guo
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Sino-Africa Joint Research Center, Chinese Academy of Sciences, Wuhan, China
| | - Enguo Fan
- State Key Laboratory of Medical Molecular Biology, Department of Microbiology and Parasitology, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
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11
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Gao Y, Chen Z, Yao W, Li D, Fu X. Gentamicin Combined With Hypoionic Shock Rapidly Eradicates Aquaculture Bacteria in vitro and in vivo. Front Microbiol 2021; 12:641846. [PMID: 33889141 PMCID: PMC8055967 DOI: 10.3389/fmicb.2021.641846] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 03/01/2021] [Indexed: 11/13/2022] Open
Abstract
Bacterial pathogens are a major cause of infectious diseases in aquatic animals. The abuse of antibiotics in the aquatic industry has led to the proliferation of antibiotic resistance. It is therefore essential to develop more effective and safer strategies to increase the efficacy and extend the life span of the antibiotics used in aquaculture. In this study, we show that six aquaculture bacterial pathogens (i.e., Aeromonas hydrophila, Vibrio alginolyticus, Edwardsiella tarda, Streptococcus iniae, Vibrio harveyi, and Vibrio fluvialis) in the stationary phase can be rapidly killed after immersion in gentamicin- or neomycin-containing, ion-free solutions for a few minutes. Such hypoionic shock treatment enhances the bacterial uptake of gentamicin in an ATP-dependent manner. Importantly, we demonstrate, as a proof of concept, that gentamicin under hypoionic shock conditions can effectively kill A. hydrophila in vivo in a skin infection model of zebrafish (Danio rerio), completely curing the infected fish. Given that pathogenic bacteria generally adhere to the skin surface and gills of aquatic animals, our strategy is of potential significance for bacterial infection control, especially for small-scale economic fish farming and ornamental fish farming. Further, the combined treatment can be completed within 5 min with a relatively small volume of solution, thus minimizing the amount of residual antibiotics in both animals and the environment.
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Affiliation(s)
- Yuanyuan Gao
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, Key Laboratory of Optoelectronic Science and Technology for Medicine of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou, China.,Engineering Research Center of Industrial Microbiology of Ministry of Education, Fujian Normal University, Fuzhou, China
| | - Zhongyu Chen
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, Key Laboratory of Optoelectronic Science and Technology for Medicine of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou, China
| | - Wei Yao
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, Key Laboratory of Optoelectronic Science and Technology for Medicine of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou, China
| | - Daliang Li
- Fujian Key Laboratory of Innate Immune Biology, Biomedical Research Center of South China, Fuzhou, China.,College of Life Science, Fujian Normal University, Fuzhou, China
| | - Xinmiao Fu
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, Key Laboratory of Optoelectronic Science and Technology for Medicine of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou, China.,Engineering Research Center of Industrial Microbiology of Ministry of Education, Fujian Normal University, Fuzhou, China
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12
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Sumiyoshi M, Miyazaki T, Makau JN, Mizuta S, Tanaka Y, Ishikawa T, Makimura K, Hirayama T, Takazono T, Saijo T, Yamaguchi H, Shimamura S, Yamamoto K, Imamura Y, Sakamoto N, Obase Y, Izumikawa K, Yanagihara K, Kohno S, Mukae H. Novel and potent antimicrobial effects of caspofungin on drug-resistant Candida and bacteria. Sci Rep 2020; 10:17745. [PMID: 33082485 PMCID: PMC7576149 DOI: 10.1038/s41598-020-74749-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 10/07/2020] [Indexed: 12/11/2022] Open
Abstract
Echinocandins, including caspofungin, micafungin, and anidulafungin, are first-line antifungal agents for the treatment of invasive candidiasis. They exhibit fungicidal activity by inhibiting the synthesis of β-1,3-D-glucan, an essential component of the fungal cell wall. However, they are active only against proliferating fungal cells and unable to completely eradicate fungal cells even after a 24 h drug exposure in standard time-kill assays. Surprisingly, we found that caspofungin, when dissolved in low ionic solutions, had rapid and potent antimicrobial activities against multidrug-resistant (MDR) Candida and bacteria cells even in non-growth conditions. This effect was not observed in 0.9% NaCl or other ion-containing solutions and was not exerted by other echinocandins. Furthermore, caspofungin dissolved in low ionic solutions drastically reduced mature biofilm cells of MDR Candida auris in only 5 min, as well as Candida-bacterial polymicrobial biofilms in a catheter-lock therapy model. Caspofungin displayed ion concentration-dependent conformational changes and intracellular accumulation with increased reactive oxygen species production, indicating a novel mechanism of action in low ionic conditions. Importantly, caspofungin dissolved in 5% glucose water did not exhibit increased toxicity to human cells. This study facilitates the development of new therapeutic strategies in the management of catheter-related biofilm infections.
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Affiliation(s)
- Makoto Sumiyoshi
- Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-12-4 Sakamoto, Nagasaki, 852-8523, Japan
- Department of Respiratory Medicine, Nagasaki University Hospital, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan
| | - Taiga Miyazaki
- Department of Respiratory Medicine, Nagasaki University Hospital, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan.
- Department of Infectious Diseases, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan.
| | - Juliann Nzembi Makau
- Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, 1-12-4 Sakamoto, Nagasaki, 852-8523, Japan
| | - Satoshi Mizuta
- Center for Bioinformatics and Molecular Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-12-4 Sakamoto, Nagasaki, 852-8523, Japan
| | - Yoshimasa Tanaka
- Center for Medical Innovation, Nagasaki University, 1-7-1 Sakamoto, Nagasaki, 852-8588, Japan
| | - Takeshi Ishikawa
- Department of Chemistry, Biotechnology, and Chemical Engineering, Graduate School of Science and Engineering, Kagoshima University, 1-21-40 Korimoto, Kagoshima, 890-0065, Japan
| | - Koichi Makimura
- Medical Mycology, Graduate School of Medicine, Teikyo University, 2-11-1 Kaga, Itabashi-ku, Tokyo, 173-8605, Japan
| | - Tatsuro Hirayama
- Department of Respiratory Medicine, Nagasaki University Hospital, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan
| | - Takahiro Takazono
- Department of Respiratory Medicine, Nagasaki University Hospital, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan
- Department of Infectious Diseases, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan
| | - Tomomi Saijo
- Department of Respiratory Medicine, Nagasaki University Hospital, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan
| | - Hiroyuki Yamaguchi
- Department of Respiratory Medicine, Nagasaki University Hospital, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan
| | - Shintaro Shimamura
- Department of Respiratory Medicine, Nagasaki University Hospital, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan
| | - Kazuko Yamamoto
- Department of Respiratory Medicine, Nagasaki University Hospital, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan
| | - Yoshifumi Imamura
- Department of Respiratory Medicine, Nagasaki University Hospital, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan
| | - Noriho Sakamoto
- Department of Respiratory Medicine, Nagasaki University Hospital, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan
| | - Yasushi Obase
- Department of Respiratory Medicine, Nagasaki University Hospital, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan
| | - Koichi Izumikawa
- Department of Infectious Diseases, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan
| | - Katsunori Yanagihara
- Department of Laboratory Medicine, Nagasaki University Hospital, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan
| | - Shigeru Kohno
- Department of Respiratory Medicine, Nagasaki University Hospital, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan
| | - Hiroshi Mukae
- Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-12-4 Sakamoto, Nagasaki, 852-8523, Japan
- Department of Respiratory Medicine, Nagasaki University Hospital, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan
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13
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Salcedo-Sora JE, Kell DB. A Quantitative Survey of Bacterial Persistence in the Presence of Antibiotics: Towards Antipersister Antimicrobial Discovery. Antibiotics (Basel) 2020; 9:E508. [PMID: 32823501 PMCID: PMC7460088 DOI: 10.3390/antibiotics9080508] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 08/08/2020] [Accepted: 08/11/2020] [Indexed: 12/17/2022] Open
Abstract
Background: Bacterial persistence to antibiotics relates to the phenotypic ability to survive lethal concentrations of otherwise bactericidal antibiotics. The quantitative nature of the time-kill assay, which is the sector's standard for the study of antibiotic bacterial persistence, is an invaluable asset for global, unbiased, and cross-species analyses. Methods: We compiled the results of antibiotic persistence from antibiotic-sensitive bacteria during planktonic growth. The data were extracted from a sample of 187 publications over the last 50 years. The antibiotics used in this compilation were also compared in terms of structural similarity to fluorescent molecules known to accumulate in Escherichia coli. Results: We reviewed in detail data from 54 antibiotics and 36 bacterial species. Persistence varies widely as a function of the type of antibiotic (membrane-active antibiotics admit the fewest), the nature of the growth phase and medium (persistence is less common in exponential phase and rich media), and the Gram staining of the target organism (persistence is more common in Gram positives). Some antibiotics bear strong structural similarity to fluorophores known to be taken up by E. coli, potentially allowing competitive assays. Some antibiotics also, paradoxically, seem to allow more persisters at higher antibiotic concentrations. Conclusions: We consolidated an actionable knowledge base to support a rational development of antipersister antimicrobials. Persistence is seen as a step on the pathway to antimicrobial resistance, and we found no organisms that failed to exhibit it. Novel antibiotics need to have antipersister activity. Discovery strategies should include persister-specific approaches that could find antibiotics that preferably target the membrane structure and permeability of slow-growing cells.
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Affiliation(s)
- Jesus Enrique Salcedo-Sora
- Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, Biosciences Building, University of Liverpool, Crown Street, Liverpool L69 7ZB, UK;
| | - Douglas B. Kell
- Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, Biosciences Building, University of Liverpool, Crown Street, Liverpool L69 7ZB, UK;
- Novo Nordisk Foundation Centre for Biosustainability, Technical University of Denmark, Building 220, Kemitorvet, 2800 Kgs. Lyngby, Denmark
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14
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Sun F, Bian M, Li Z, Lv B, Gao Y, Wang Y, Fu X. 5-Methylindole Potentiates Aminoglycoside Against Gram-Positive Bacteria Including Staphylococcus aureus Persisters Under Hypoionic Conditions. Front Cell Infect Microbiol 2020; 10:84. [PMID: 32185144 PMCID: PMC7058972 DOI: 10.3389/fcimb.2020.00084] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 02/18/2020] [Indexed: 11/23/2022] Open
Abstract
Antibiotic resistance/tolerance has become a severe threat to human and animal health. To combat antibiotic-resistant/tolerant bacteria, it is of significance to improve the efficacy of traditional antibiotics. Here we show that indole potentiates tobramycin to kill stationary-phase Staphylococcus aureus cells after a short, combined treatment, with its derivative 5-methylindole being the most potent compound tested and with the absence of ions as a prerequisite. Consistently, this combined treatment also kills various types of S. aureus persister cells as induced by the protonophore CCCP, nutrient shift, or starvation, as well as methicillin-resistant S. aureus (MRSA) cells. Importantly, 5-methylindole potentiates tobramycin killing of S. aureus persisters in a mouse acute skin wound model. Furthermore, 5-methylindole facilitates killing of many strains of gram-positive pathogens such as Staphylococcus epidermidis, Enterococcus faecalis, and Streptococcus pyogenes by aminoglycoside antibiotics, whereas it suppresses the action of aminoglycoside against the gram-negative pathogens Escherichia coli and Shigella flexneri. In conclusion, our work may pave the way for the development of indole derivatives as adjuvants to potentiate aminoglycosides against gram-positive pathogens.
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Affiliation(s)
- Fengqi Sun
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou, China
| | - Mengmeng Bian
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou, China
| | - Zhongyan Li
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou, China
| | - Boyan Lv
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou, China
| | - Yuanyuan Gao
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou, China.,Engineering Research Center of Industrial Microbiology of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou, China
| | - Yan Wang
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou, China
| | - Xinmiao Fu
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou, China.,Engineering Research Center of Industrial Microbiology of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou, China
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15
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Zhao Y, Lv B, Sun F, Liu J, Wang Y, Gao Y, Qi F, Chang Z, Fu X. Rapid Freezing Enables Aminoglycosides To Eradicate Bacterial Persisters via Enhancing Mechanosensitive Channel MscL-Mediated Antibiotic Uptake. mBio 2020; 11:e03239-19. [PMID: 32047133 PMCID: PMC7018644 DOI: 10.1128/mbio.03239-19] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 01/06/2020] [Indexed: 12/24/2022] Open
Abstract
Bacterial persisters exhibit noninherited antibiotic tolerance and are linked to the recalcitrance of bacterial infections. It is very urgent but also challenging to develop antipersister strategies. Here, we report that 10-s freezing with liquid nitrogen dramatically enhances the bactericidal action of aminoglycoside antibiotics by 2 to 6 orders of magnitude against many Gram-negative pathogens, with weaker potentiation effects on Gram-positive bacteria. In particular, antibiotic-tolerant Escherichia coli and Pseudomonas aeruginosa persisters-which were prepared by treating exponential-phase cells with ampicillin, ofloxacin, the protonophore cyanide m-chlorophenyl hydrazone (CCCP), or bacteriostatic antibiotics-can be effectively killed. We demonstrated, as a proof of concept, that freezing potentiated the aminoglycosides' killing of P. aeruginosa persisters in a mouse acute skin wound model. Mechanistically, freezing dramatically increased the bacterial uptake of aminoglycosides regardless of the presence of CCCP, indicating that the effects are independent of the proton motive force (PMF). In line with these results, we found that the effects were linked to freezing-induced cell membrane damage and were attributable, at least partly, to the mechanosensitive ion channel MscL, which was able to directly mediate such freezing-enhanced aminoglycoside uptake. In view of these results, we propose that the freezing-induced aminoglycoside potentiation is achieved by freezing-induced cell membrane destabilization, which, in turn, activates the MscL channel, which is able to effectively take up aminoglycosides in a PMF-independent manner. Our work may pave the way for the development of antipersister strategies that utilize the same mechanism as freezing but do so without causing any injury to animal cells.IMPORTANCE Antibiotics have long been used to successfully kill bacterial pathogens, but antibiotic resistance/tolerance usually has led to the failure of antibiotic therapy, and it has become a severe threat to human health. How to improve the efficacy of existing antibiotics is of importance for combating antibiotic-resistant/tolerant pathogens. Here, we report that 10-s rapid freezing with liquid nitrogen dramatically enhanced the bactericidal action of aminoglycoside antibiotics by 2 to 6 orders of magnitude against many bacterial pathogens in vitro and also in a mouse skin wound model. In particular, such combined treatment was able to effectively kill persister cells of Escherichia coli and Pseudomonas aeruginosa, which are per se tolerant of conventional treatment with bactericidal antibiotics for several hours. We also demonstrated that freezing-induced aminoglycoside potentiation was apparently linked to freezing-induced cell membrane damage that may have activated the mechanosensitive ion channel MscL, which, in turn, was able to effectively uptake aminoglycoside antibiotics in a proton motive force-independent manner. Our report sheds light on the development of a new strategy against bacterial pathogens by combining existing antibiotics with a conventional physical treatment or with MscL agonists.
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Affiliation(s)
- Yanna Zhao
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, Key Laboratory of Optoelectronic Science and Technology for Medicine of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province, China
| | - Boyan Lv
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, Key Laboratory of Optoelectronic Science and Technology for Medicine of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province, China
| | - Fengqi Sun
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, Key Laboratory of Optoelectronic Science and Technology for Medicine of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province, China
| | - Jiafeng Liu
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
| | - Yan Wang
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, Key Laboratory of Optoelectronic Science and Technology for Medicine of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province, China
| | - Yuanyuan Gao
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, Key Laboratory of Optoelectronic Science and Technology for Medicine of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province, China
- Engineering Research Center of Industrial Microbiology of Ministry of Education, Fujian Normal University, Fuzhou City, Fujian Province, China
| | - Feng Qi
- Engineering Research Center of Industrial Microbiology of Ministry of Education, Fujian Normal University, Fuzhou City, Fujian Province, China
| | - Zengyi Chang
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
| | - Xinmiao Fu
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, Key Laboratory of Optoelectronic Science and Technology for Medicine of Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou City, Fujian Province, China
- Engineering Research Center of Industrial Microbiology of Ministry of Education, Fujian Normal University, Fuzhou City, Fujian Province, China
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