1
|
Liu X, Wang P, Yuan N, Zhai Y, Yang Y, Hao M, Zhang M, Zhou D, Liu W, Jin Y, Wang A. The (p)ppGpp synthetase Rsh promotes rifampicin tolerant persister cell formation in Brucella abortus by regulating the type II toxin-antitoxin module mbcTA. Front Microbiol 2024; 15:1395504. [PMID: 38841069 PMCID: PMC11150624 DOI: 10.3389/fmicb.2024.1395504] [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: 03/04/2024] [Accepted: 05/01/2024] [Indexed: 06/07/2024] Open
Abstract
Persister cells are transiently tolerant to antibiotics and are associated with recalcitrant chronic infections due to recolonization of host cells after antibiotic removal. Brucella spp. are facultative pathogens that establish intracellular infection cycles in host cells which results in chronic persistent infections. Brucella abortus forms multi-drug persister cells which are promoted by the (p)ppGpp synthetase Rsh during rifampicin exposure. Here, we confirmed that Rsh promoted persister cells formation in B. abortus stationary phase treated with rifampicin and enrofloxacin. Deletion of the gene for Rsh decreased persister cells level in the presence of these drugs in different growth phases. However, persister cells formation by deletion strain varied in different growth phases in the presence of other antibiotics. Rsh also was involved in persister cells formation during rifampicin treatment under certain stress conditions, including acidic conditions, exposure to PBS, and heat stress. Moreover, Rsh impacted persister cell levels during rifampicin or enrofloxacin treatment in RAW264.7 macrophages. Certain typeIItoxin-antitoxin modules were upregulated under various stress conditions in B. abortus. We established that Rsh positively regulated the type II toxin-antitoxin mbcTA. Moreover, rifampicin-tolerant persister cells formation was elevated and ATP levels were decreased when mbcTA promoter was overexpressed in Rsh deletion background in stationary phase. Our results establish that (p)ppGpp synthetase Rsh plays a key role in B. abortus persistence and may serve as a potent novel target in combination with rifampicin in the development of new therapeutic approaches and prevention strategies to treat chronic infections of Brucella.
Collapse
Affiliation(s)
- Xiaofang Liu
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University, Xianyang, China
| | - Pingping Wang
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University, Xianyang, China
| | - Ningqiu Yuan
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University, Xianyang, China
| | - Yunyi Zhai
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University, Xianyang, China
| | - Yuanhao Yang
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University, Xianyang, China
| | - Mingyue Hao
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University, Xianyang, China
| | - Mingxing Zhang
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China
- College of Animal Science and Technology, Northwest A&F University, Xianyang, China
| | - Dong Zhou
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University, Xianyang, China
| | - Wei Liu
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University, Xianyang, China
| | - Yaping Jin
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University, Xianyang, China
| | - Aihua Wang
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University, Xianyang, China
| |
Collapse
|
2
|
Zhu HY, Xiang WL, Cai T, Zhang M, Wang HY. PemK's Arg24 is a crucial residue for PemIK toxin-antitoxin system to induce the persistence of Weissella cibaria against ciprofloxacin stress. Front Microbiol 2024; 15:1402319. [PMID: 38808277 PMCID: PMC11130411 DOI: 10.3389/fmicb.2024.1402319] [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: 03/17/2024] [Accepted: 04/15/2024] [Indexed: 05/30/2024] Open
Abstract
The toxin-antitoxin (TA) system plays a key role in bacteria escaping antibiotic stress with persistence, however, the mechanisms by which persistence is controlled remain poorly understood. Weissella cibaria, a novel probiotic, can enters a persistent state upon encountering ciprofloxacin stress. Conversely, it resumes from the persistence when ciprofloxacin stress is relieved or removed. Here, it was found that PemIK TA system played a role in transitioning between these two states. And the PemIK was consisted of PemK, an endonuclease toxic to mRNA, and antitoxin PemI which neutralized its toxicity. The PemK specifically cleaved the U↓AUU in mRNA encoding enzymes involved in glycolysis, TCA cycle and respiratory chain pathways. This cleavage event subsequently disrupted the crucial cellular processes such as hydrogen transfer, electron transfer, NADH and FADH2 synthesis, ultimately leading to a decrease in ATP levels and an increase in membrane depolarization and persister frequency. Notably, Arg24 was a critical active residue for PemK, its mutation significantly reduced the mRNA cleavage activity and the adverse effects on metabolism. These insights provided a clue to comprehensively understand the mechanism by which PemIK induced the persistence of W. cibaria to escape ciprofloxacin stress, thereby highlighting another novel aspect PemIK respond for antibiotic stress.
Collapse
Affiliation(s)
- Hao-Yu Zhu
- School of Food and Bioengineering, Xihua University, Chengdu, China
| | - Wen-Liang Xiang
- School of Food and Bioengineering, Xihua University, Chengdu, China
- Key Laboratory of Food Microbiology of Sichuan, Xihua University, Chengdu, China
| | - Ting Cai
- School of Food and Bioengineering, Xihua University, Chengdu, China
- Key Laboratory of Food Microbiology of Sichuan, Xihua University, Chengdu, China
| | - Min Zhang
- School of Food and Bioengineering, Xihua University, Chengdu, China
| | - Han-Yang Wang
- School of Food and Bioengineering, Xihua University, Chengdu, China
| |
Collapse
|
3
|
Coşkun USŞ, Dagcioglu Y. Evaluation of toxin-antitoxin genes, antibiotic resistance, and virulence genes in Pseudomonas aeruginosa isolates. REVISTA DA ASSOCIACAO MEDICA BRASILEIRA (1992) 2023; 69:51-55. [PMID: 36820713 PMCID: PMC9937597 DOI: 10.1590/1806-9282.20220493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 10/05/2022] [Indexed: 02/19/2023]
Abstract
OBJECTIVE Toxin-antitoxin genes RelBE and HigBA are known to be involved in the formation of biofilm, which is an important virulence factor for Pseudomonas aeruginosa. The purpose of this study was to determine the presence of toxin-antitoxin genes and exoenzyme S and exotoxin A virulence genes in P. aeruginosa isolates and whether there is a relationship between toxin-antitoxin genes and virulence genes as well as antibiotic resistance. METHODS Identification of the isolates and antibiotic susceptibilities was determined by a VITEK 2 (bioMérieux, France) automated system. The presence of toxin-antitoxin genes, virulence genes, and transcription levels were detected by real-time polymerase chain reaction. RESULTS RelBE and HigBA genes were detected in 94.3% (82/87) of P. aeruginosa isolates, and exoenzyme S and exotoxin A genes were detected in all of the isolates (n=87). All of the isolates that harbor the toxin-antitoxin and virulence genes were transcribed. There was a significant increase in the RelBE gene transcription level in imipenem- and meropenem-sensitive isolates and in the HigBA gene transcription level in amikacin-sensitive isolates (p<0.05). There was a significant correlation between RelBE and exoenzyme S (p=0.001). CONCLUSION The findings suggest that antibiotic resistance may be linked to toxin-antitoxin genes. Furthermore, the relationship between RelBE and exoenzyme S indicates that toxin-antitoxin genes in P. aeruginosa isolates are not only related to antibiotic resistance but also play an influential role in bacterial virulence. Larger collections of comprehensive studies on this subject are required. These studies should contribute significantly to the solution of the antibiotic resistance problem.
Collapse
Affiliation(s)
- Umut Safiye Şay Coşkun
- Tokat Gaziosmanpaşa University, Faculty of Medicine, Department of Medical Microbiology – Tokat, Turkey.,Corresponding author:
| | - Yelda Dagcioglu
- Tokat Gaziosmanpaşa University, Training and Research Hospital, Genetic Laboratory – Tokat, Turkey
| |
Collapse
|
4
|
Li M, Guo N, Song G, Huang Y, Wang L, Zhang Y, Wang T. Type II Toxin-Antitoxin Systems in Pseudomonas aeruginosa. Toxins (Basel) 2023; 15:164. [PMID: 36828478 PMCID: PMC9966142 DOI: 10.3390/toxins15020164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 02/03/2023] [Accepted: 02/14/2023] [Indexed: 02/22/2023] Open
Abstract
Toxin-antitoxin (TA) systems are typically composed of a stable toxin and a labile antitoxin; the latter counteracts the toxicity of the former under suitable conditions. TA systems are classified into eight types based on the nature and molecular modes of action of the antitoxin component so far. The 10 pairs of TA systems discovered and experimentally characterised in Pseudomonas aeruginosa are type II TA systems. Type II TA systems have various physiological functions, such as virulence and biofilm formation, protection host against antibiotics, persistence, plasmid maintenance, and prophage production. Here, we review the type II TA systems of P. aeruginosa, focusing on their biological functions and regulatory mechanisms, providing potential applications for the novel drug design.
Collapse
Affiliation(s)
| | | | | | | | | | - Yani Zhang
- Provincial Key Laboratory of Biotechnology, Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi’an 710069, China
| | - Tietao Wang
- Provincial Key Laboratory of Biotechnology, Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi’an 710069, China
| |
Collapse
|
5
|
Song Y, Tang H, Bao R. Comparative analysis of five type II TA systems identified in Pseudomonas aeruginosa reveals their contributions to persistence and intracellular survival. Front Cell Infect Microbiol 2023; 13:1127786. [PMID: 36844395 PMCID: PMC9948252 DOI: 10.3389/fcimb.2023.1127786] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 02/01/2023] [Indexed: 02/11/2023] Open
Abstract
Background Pseudomonas aeruginosa is a grave nosocomial pathogen that persistently inhabits the lungs of patients with cystic fibrosis (CF) and causes various chronic infections. The bacterial toxin-antitoxin (TA) system is associated with latent and long-term infections, but the underlying mechanisms remain to be fully characterized. Methods We here investigated the diversity and function of five genomic type II TA systems widely distributed among P. aeruginosa clinical isolates. We also examined the distinct structural features of the toxin protein from different TA systems and characterized their contributions to persistence, invasion ability, and intracellular infection caused by P. aeruginosa. Results ParDE, PA1030/PA1029, and HigBA could modulate persister cell formation under treatment with specific antibiotics. Furthermore, cell-based transcriptional and invasion assays revealed that PA1030/PA1029 and HigBA TA systems were critical for intracellular survival. Discussion Our results highlight the prevalence and diverse roles of type II TA systems in P. aeruginosa and evaluate the possibility of using PA1030/PA1029 and HigBA TA pairs as targets for novel antibiotic treatments.
Collapse
Affiliation(s)
- Yingjie Song
- College of Life Science, Sichuan Normal University, Chengdu, China
| | - Hong Tang
- Division of Infectious Diseases, State Key Laboratory of Biotherapy and Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China
- *Correspondence: Rui Bao, ; Hong Tang,
| | - Rui Bao
- Division of Infectious Diseases, State Key Laboratory of Biotherapy and Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China
- *Correspondence: Rui Bao, ; Hong Tang,
| |
Collapse
|
6
|
Identification of chromosomal type II toxin–antitoxin system from plant pathogenic Pseudomonas cichorii JBC 1. Mol Cell Toxicol 2022. [DOI: 10.1007/s13273-022-00324-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
|
7
|
Shi X, Zarkan A. Bacterial survivors: evaluating the mechanisms of antibiotic persistence. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 36748698 DOI: 10.1099/mic.0.001266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Bacteria withstand antibiotic onslaughts by employing a variety of strategies, one of which is persistence. Persistence occurs in a bacterial population where a subpopulation of cells (persisters) survives antibiotic treatment and can regrow in a drug-free environment. Persisters may cause the recalcitrance of infectious diseases and can be a stepping stone to antibiotic resistance, so understanding persistence mechanisms is critical for therapeutic applications. However, current understanding of persistence is pervaded by paradoxes that stymie research progress, and many aspects of this cellular state remain elusive. In this review, we summarize the putative persister mechanisms, including toxin-antitoxin modules, quorum sensing, indole signalling and epigenetics, as well as the reasons behind the inconsistent body of evidence. We highlight present limitations in the field and underscore a clinical context that is frequently neglected, in the hope of supporting future researchers in examining clinically important persister mechanisms.
Collapse
Affiliation(s)
- Xiaoyi Shi
- Cambridge Centre for International Research, Cambridge CB4 0PZ, UK
| | - Ashraf Zarkan
- Department of Genetics, University of Cambridge, Cambridge CB2 3EH, UK
| |
Collapse
|
8
|
Wang C, Niu C, Hidayatullah KM, Xue L, Zhu Z, Niu L. Structural insights into the PrpTA toxin-antitoxin system in Pseudoalteromonas rubra. Front Microbiol 2022; 13:1053255. [PMID: 36504814 PMCID: PMC9731233 DOI: 10.3389/fmicb.2022.1053255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Accepted: 10/31/2022] [Indexed: 11/27/2022] Open
Abstract
Bacteria could survive stresses by a poorly understood mechanism that contributes to the emergence of bacterial persisters exhibiting multidrug tolerance (MDT). Recently, Pseudoalteromonas rubra prpAT module was found to encode a toxin PrpT and corresponding cognate antidote PrpA. In this study, we first reported multiple individual and complex structures of PrpA and PrpT, which uncovered the high-resolution three-dimensional structure of the PrpT:PrpA2:PrpT heterotetramer with the aid of size exclusion chromatography-multi-angle light scattering experiments (SEC-MALS). PrpT:PrpA2:PrpT is composed of a PrpA homodimer and two PrpT monomers which are relatively isolated from each other and from ParE family. The superposition of antitoxin monomer structures from these structures highlighted the flexible C-terminal domain (CTD). A striking conformational change in the CTDs of PrpA homodimer depolymerized from homotetramer was provoked upon PrpT binding, which accounts for the unique PrpT-PrpARHH mutual interactions and further neutralizes the toxin PrpT. PrpA2-54-form I and II crystal structures both contain a doughnut-shaped hexadecamer formed by eight homodimers organized in a cogwheel-like form via inter-dimer interface dominated by salt bridges and hydrogen bonds. Moreover, PrpA tends to exist in solution as a homodimer other than a homotetramer (SEC-MALS) in the absence of flexible CTD. Multiple multi-dimers, tetramer and hexamer included, of PrpA2-54 mediated by the symmetric homodimer interface and the complicated inter-dimer interface could be observed in the solution. SEC-MALS assays highlighted that phosphate buffer (PB) and the increase in the concentration appear to be favorable for the PrpA2-54 oligomerization in the solution. Taken together with previous research, a model of PrpA2-54 homotetramer in complex with prpAT promoter and the improved mechanism underlying how PrpTA controls the plasmid replication were proposed here.
Collapse
Affiliation(s)
- Chenchen Wang
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
| | - Chuanying Niu
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Center for Infection and Immunity, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Khan Muhammad Hidayatullah
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
| | - Lu Xue
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Center for Infection and Immunity, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Zhongliang Zhu
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
| | - Liwen Niu
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
| |
Collapse
|
9
|
de Oliveira HL, Dias GM, Neves BC. Genome sequence of Pseudomonas aeruginosa PA1-Petro—A role model of environmental adaptation and a potential biotechnological tool. Heliyon 2022; 8:e11566. [DOI: 10.1016/j.heliyon.2022.e11566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 08/12/2022] [Accepted: 11/07/2022] [Indexed: 11/16/2022] Open
|
10
|
Qiu J, Zhai Y, Wei M, Zheng C, Jiao X. Toxin–antitoxin systems: Classification, biological roles, and applications. Microbiol Res 2022; 264:127159. [DOI: 10.1016/j.micres.2022.127159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 08/02/2022] [Accepted: 08/03/2022] [Indexed: 11/28/2022]
|
11
|
Baquero F, del Campo R, Martínez JL. Interventions in Nicotinamide Adenine Dinucleotide Metabolism, the Intestinal Microbiota and Microcin Peptide Antimicrobials. Front Mol Biosci 2022; 9:861603. [PMID: 35372517 PMCID: PMC8967132 DOI: 10.3389/fmolb.2022.861603] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 02/22/2022] [Indexed: 11/23/2022] Open
Abstract
A proper NADH/NAD + balance allows for the flow of metabolic and catabolic activities determining cellular growth. In Escherichia coli, more than 80 NAD + dependent enzymes are involved in all major metabolic pathways, including the post-transcriptional build-up of thiazole and oxazole rings from small linear peptides, which is a critical step for the antibiotic activity of some microcins. In recent years, NAD metabolism boosting drugs have been explored, mostly precursors of NAD + synthesis in human cells, with beneficial effects on the aging process and in preventing oncological and neurological diseases. These compounds also enhance NAD + metabolism in the human microbiota, which contributes to these beneficial effects. On the other hand, inhibition of NAD + metabolism has been proposed as a therapeutic approach to reduce the growth and propagation of tumor cells and mitigating inflammatory bowel diseases; in this case, the activity of the microbiota might mitigate therapeutic efficacy. Antibiotics, which reduce the effect of microbiota, should synergize with NAD + metabolism inhibitors, but these drugs might increase the proportion of antibiotic persistent populations. Conversely, antibiotics might have a stronger killing effect on bacteria with active NAD + production and reduce the cooperation of NAD + producing bacteria with tumoral cells. The use of NADH/NAD + modulators should take into consideration the use of antibiotics and the population structure of the microbiota.
Collapse
Affiliation(s)
- Fernando Baquero
- Department of Microbiology, Ramón y Cajal University Hospital and Ramón y Cajal Institute for Health Research (IRYCIS), Madrid, Spain
- Network Center for Research in Epidemiology and Public Health (CIBER-ESP), Madrid, Spain
- *Correspondence: Fernando Baquero,
| | - Rosa del Campo
- Department of Microbiology, Ramón y Cajal University Hospital and Ramón y Cajal Institute for Health Research (IRYCIS), Madrid, Spain
- Network Center for Research in Infectious Diseases (CIBER-INFEC), Madrid, Spain
| | | |
Collapse
|
12
|
Roy S, Bahar AA, Gu H, Nangia S, Sauer K, Ren D. Persister control by leveraging dormancy associated reduction of antibiotic efflux. PLoS Pathog 2021; 17:e1010144. [PMID: 34890435 PMCID: PMC8716142 DOI: 10.1371/journal.ppat.1010144] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 12/29/2021] [Accepted: 11/24/2021] [Indexed: 11/19/2022] Open
Abstract
Persistent bacterial infections do not respond to current antibiotic treatments and thus present a great medical challenge. These conditions have been linked to the formation of dormant subpopulations of bacteria, known as persister cells, that are growth-arrested and highly tolerant to conventional antibiotics. Here, we report a new strategy of persister control and demonstrate that minocycline, an amphiphilic antibiotic that does not require active transport to penetrate bacterial membranes, is effective in killing Escherichia coli persister cells [by 70.8 ± 5.9% (0.53 log) at 100 μg/mL], while being ineffective in killing normal cells. Further mechanistic studies revealed that persister cells have reduced drug efflux and accumulate more minocycline than normal cells, leading to effective killing of this dormant subpopulation upon wake-up. Consistently, eravacycline, which also targets the ribosome but has a stronger binding affinity than minocycline, kills persister cells by 3 logs when treated at 100 μg/mL. In summary, the findings of this study reveal that while dormancy is a well-known cause of antibiotic tolerance, it also provides an Achilles’ heel for controlling persister cells by leveraging dormancy associated reduction of drug efflux. Bacterial persister cells are dormant phenotypic variants that are highly tolerant to most antibiotics; and thus, present a major challenge to infection control. This motivated us to develop new strategies that can specifically target the persister population. It is known that persister formation is associated with reduced membrane potential and cellular activities. Thus, we hypothesize that persister cells have reduced drug efflux compared to normal cells and accumulate more antimicrobial agents that can penetrate the membranes of persister cells. By testing this hypothesis, we developed a new set of criteria for selecting persister control agents and demonstrated effective control of Escherichia coli persister cells by minocycline, rifamycin SV, and eravacycline. Our results revealed that these agents are more effective against persister cells than normal cells and the killing occurred during persister wake-up. Collectively, these results demonstrate a new strategy for persister control by leveraging dormancy associated changes in bacterial physiology. The findings may contribute to future drug discovery and the treatment of persistent infections.
Collapse
Affiliation(s)
- Sweta Roy
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York, United States of America
| | - Ali Adem Bahar
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York, United States of America
| | - Huan Gu
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York, United States of America
| | - Shikha Nangia
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York, United States of America
| | - Karin Sauer
- Department of Biological Sciences, Binghamton University, Binghamton, New York, United States of America
| | - Dacheng Ren
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York, United States of America
- Department of Civil and Environmental Engineering, Syracuse University, Syracuse, New York, United States of America
- Department of Biology, Syracuse University, Syracuse, New York, United States of America
- * E-mail:
| |
Collapse
|
13
|
Sindeldecker D, Stoodley P. The many antibiotic resistance and tolerance strategies of Pseudomonas aeruginosa. Biofilm 2021; 3:100056. [PMID: 34471871 PMCID: PMC8387898 DOI: 10.1016/j.bioflm.2021.100056] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 08/17/2021] [Accepted: 08/18/2021] [Indexed: 12/15/2022] Open
Abstract
Pseudomonas aeruginosa is a bacterial pathogen associated with a wide range of infections and utilizes several strategies to establish and maintain infection including biofilm production, multidrug resistance, and antibiotic tolerance. Multidrug resistance in P. aeruginosa, as well as in all other bacterial pathogens, is a growing concern. Aminoglycoside resistance, in particular, is a major concern in P. aeruginosa infections and must be better understood in order to maintain effective clinical treatment. In this review, the various antibiotic resistance and tolerance mechanisms of Pseudomonas are explored including: classic mutation driven resistance, adaptive resistance, persister cells, small colony variants, phoenix colonies, and biofilms. It is important to further characterize each of these phenotypes and continue to evaluate antibiotic surviving isolates for novel driving mechanisms, so that we are better prepared to combat the rising number of recurrent and recalcitrant infections.
Collapse
Affiliation(s)
- Devin Sindeldecker
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, USA
- Biomedical Sciences Graduate Program, The Ohio State University, Columbus, OH, USA
| | - Paul Stoodley
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, USA
- Department of Orthopaedics, The Ohio State University, Columbus, OH, USA
- National Center for Advanced Tribology at Southampton (nCATS), Mechanical Engineering, University of Southampton, Southampton, UK
| |
Collapse
|