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Maghembe RS, Magulye MAK, Eilu E, Sekyanzi S, Makaranga A, Mwesigwa S, Katagirya E. A sophisticated virulence repertoire and colistin resistance of Citrobacter freundii ST150 from a patient with sepsis admitted to ICU in a tertiary care hospital in Uganda, East Africa: Insight from genomic and molecular docking analyses. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2024; 120:105591. [PMID: 38604286 PMCID: PMC11069293 DOI: 10.1016/j.meegid.2024.105591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 04/02/2024] [Accepted: 04/08/2024] [Indexed: 04/13/2024]
Abstract
Sepsis and multidrug resistance comprise a complex of factors attributable to mortality among intensive care unit (ICU) patients globally. Pathogens implicated in sepsis are diverse, and their virulence and drug resistance remain elusive. From a tertiary care hospital ICU in Uganda, we isolated a Citrobacter freundii strain RSM030 from a patient with sepsis and phenotypically tested it against a panel of 16 antibiotics including imipenem levofloxacin, cotrimoxazole and colistin, among others. We sequenced the organism's genome and integrated multilocus sequencing (MLST), PathogenFinder with Virulence Factor analyzer (VFanalyzer) to establish its pathogenic relevance. Thereafter, we combined antiSMASH and PRISM genome mining with molecular docking to predict biosynthetic gene clusters (BGCs), pathways, toxin structures and their potential targets in-silico. Finally, we coupled ResFinder with comprehensive antibiotic resistance database (CARD) to scrutinize the genomic antimicrobial resistance profile of the isolate. From PathogenFinder and MLST, this organism was confirmed to be a human pathogen (p = 0.843), sequence type (ST)150, whose virulence is determined by chromosomal type III secretion system (T3SS) (the injectosome) and plasmid-encoded type IV secretion system (T4SS), the enterobactin biosynthetic gene cluster and biofilm formation through the pgaABCD operon. Pathway and molecular docking analyses revealed that the shikimate pathway can generate a toxin targeting multiple host proteins including spectrin, detector of cytokinesis protein 2 (Dock2) and plasmalemma vesicle-associated protein (PLVAP), potentially distorting the host cell integrity. From phenotypic antibiotic testing, we found indeterminate results for amoxicillin/clavulanate and levofloxacin, with resistance to cotrimoxazole and colistin. Detailed genome analysis revealed chromosomal beta lactam resistance genes, i.e. blaCMY-79, blaCMY-116 and blaTEM-1B, along with multiple mutations of the lipopolysaccharide modifying operon genes PmrA/PmrB, pmrD, mgrA/mgrB and PhoP/PhoQ, conferring colistin resistance. From these findings, we infer that Citrobacter freundii strain RSM030 is implicated in sepsis and resistance to standard antibiotics, including colistin, the last resort.
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Affiliation(s)
- Reuben S Maghembe
- Biological and Marine Sciences Unit, Faculty of Natural and Applied Sciences, Marian University College, P. O. Box 47, Bagamoyo, Tanzania; Department of Immunology and Molecular Biology, College of Health Sciences, Makerere University, P. O. Box 7072, Kampala, Uganda; Department of Microbiology and Immunology, Faculty of Biomedical Sciences, Kampala International University, Wester Campus, Ishaka, Uganda.; Microbiology Section, Department of Biological Sciences, University of Botswana, Private Bag 0704, Gaborone, Botswana.
| | - Maximilian A K Magulye
- Department of Immunology and Molecular Biology, College of Health Sciences, Makerere University, P. O. Box 7072, Kampala, Uganda
| | - Emmanuel Eilu
- Department of Microbiology and Immunology, Faculty of Biomedical Sciences, Kampala International University, Wester Campus, Ishaka, Uganda
| | - Simon Sekyanzi
- Department of Medical Microbiology, College of Health Sciences, Makerere University, P. O. Box 7072, Kampala, Uganda
| | - Abdalah Makaranga
- Biological and Marine Sciences Unit, Faculty of Natural and Applied Sciences, Marian University College, P. O. Box 47, Bagamoyo, Tanzania
| | - Savannah Mwesigwa
- Department of Immunology and Molecular Biology, College of Health Sciences, Makerere University, P. O. Box 7072, Kampala, Uganda
| | - Eric Katagirya
- Department of Immunology and Molecular Biology, College of Health Sciences, Makerere University, P. O. Box 7072, Kampala, Uganda
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Ge W, Yang Q, Wang H, Pan C, Lv M, Liang L, Ya S, Luo X, Wang W, Ma H. Acid tolerance response of Salmonella during the squid storage and its amine production capacity analysis. Arch Microbiol 2024; 206:139. [PMID: 38436732 DOI: 10.1007/s00203-024-03853-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2023] [Revised: 01/16/2024] [Accepted: 01/17/2024] [Indexed: 03/05/2024]
Abstract
Salmonella exhibits a strong inducible acid tolerance response (ATR) under weak acid conditions, and can also induce high-risk strains that are highly toxic, acid resistant, and osmotic pressure resistant to aquatic products. However, the induction mechanism is not yet clear. Therefore, this study aims to simulate the slightly acidic, low-temperature, and high-protein environment during squid processing and storage. Through λRed gene knockout, exploring the effects of low-acid induction, long-term low-temperature storage, and two-component regulation on Salmonella ATR. In this study, we found the two-component system, PhoP/PhoQ and PmrA/PmrB in Salmonella regulates the amino acid metabolism system and improves bacterial acid tolerance by controlling arginine and lysine. Compared with the two indicators of total biogenic amine and diamine content, biogenic amine index and quality index were more suitable for evaluating the quality of aquatic products. The result showed that low-temperature treatment could inhibit Salmonella-induced ATR, which further explained the ATR mechanism from the amino acid metabolism.
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Affiliation(s)
- Wei Ge
- Guangxi Engineering Research Center of Processing and Storage of Characteristic and Advantage Aquatic Products, Guangxi Academy of Fishery Sciences, Nanning, 530021, China
| | - Qiong Yang
- Guangxi Engineering Research Center of Processing and Storage of Characteristic and Advantage Aquatic Products, Guangxi Academy of Fishery Sciences, Nanning, 530021, China
| | - Hui Wang
- Guangxi Engineering Research Center of Processing and Storage of Characteristic and Advantage Aquatic Products, Guangxi Academy of Fishery Sciences, Nanning, 530021, China
| | - Chuanyan Pan
- Guangxi Engineering Research Center of Processing and Storage of Characteristic and Advantage Aquatic Products, Guangxi Academy of Fishery Sciences, Nanning, 530021, China
| | - Min Lv
- Guangxi Engineering Research Center of Processing and Storage of Characteristic and Advantage Aquatic Products, Guangxi Academy of Fishery Sciences, Nanning, 530021, China
| | - Lingyun Liang
- Aquatic Technology Promotion Station in Jinchengjiang District, Hechi, 547000, China
| | - Shiya Ya
- Guangxi Engineering Research Center of Processing and Storage of Characteristic and Advantage Aquatic Products, Guangxi Academy of Fishery Sciences, Nanning, 530021, China
| | - Xu Luo
- Guangxi Engineering Research Center of Processing and Storage of Characteristic and Advantage Aquatic Products, Guangxi Academy of Fishery Sciences, Nanning, 530021, China
| | - Weisheng Wang
- College of Pharmacy, Guangxi University of Chinese Medicine, Nanning, 530200, China.
| | - Huawei Ma
- Guangxi Engineering Research Center of Processing and Storage of Characteristic and Advantage Aquatic Products, Guangxi Academy of Fishery Sciences, Nanning, 530021, China.
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Ghoshal M, Bechtel TD, Gibbons JG, McLandsborough L. Adaptive laboratory evolution of Salmonella enterica in acid stress. Front Microbiol 2023; 14:1285421. [PMID: 38033570 PMCID: PMC10687551 DOI: 10.3389/fmicb.2023.1285421] [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: 08/29/2023] [Accepted: 10/16/2023] [Indexed: 12/02/2023] Open
Abstract
Introduction Adaptive laboratory evolution (ALE) studies play a crucial role in understanding the adaptation and evolution of different bacterial species. In this study, we have investigated the adaptation and evolution of Salmonella enterica serovar Enteritidis to acetic acid using ALE. Materials and methods Acetic acid concentrations below the minimum inhibitory concentration (sub-MIC) were used. Four evolutionary lineages (EL), namely, EL1, EL2, EL3, and EL4, of S. Enteritidis were developed, each demonstrating varying levels of resistance to acetic acid. Results The acetic acid MIC of EL1 remained constant at 27 mM throughout 70 days, while the MIC of EL2, EL3, and EL4 increased throughout the 70 days. EL4 was adapted to the highest concentration of acetic acid (30 mM) and demonstrated the highest increase in its MIC against acetic acid throughout the study, reaching an MIC of 35 mM on day 70. The growth rates of the evolved lineages increased over time and were dependent on the concentration of acetic acid used during the evolutionary process. EL4 had the greatest increase in growth rate, reaching 0.33 (h-1) after 70 days in the presence of 30 mM acetic acid as compared to EL1, which had a growth rate of 0.2 (h-1) after 70 days with no exposure to acetic acid. Long-term exposure to acetic acid led to an increased MIC of human antibiotics such as ciprofloxacin and meropenem against the S. enterica evolutionary lineages. The MIC of ciprofloxacin for EL1 stayed constant at 0.016 throughout the 70 days while that of EL4 increased to 0.047. Bacterial whole genome sequencing revealed single-nucleotide polymorphisms in the ELs in various genes known to be involved in S. enterica virulence, pathogenesis, and stress response including phoP, phoQ, and fhuA. We also observed genome deletions in some of the ELs as compared to the wild-type S. Enteritidis which may have contributed to the bacterial acid adaptation. Discussion This study highlights the potential for bacterial adaptation and evolution under environmental stress and underscores the importance of understanding the development of cross resistance to antibiotics in S. enterica populations. This study serves to enhance our understanding of the pathogenicity and survival strategies of S. enterica under acetic acid stress.
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Affiliation(s)
- Mrinalini Ghoshal
- Department of Microbiology, University of Massachusetts, Amherst, MA, United States
- Department of Food Science, University of Massachusetts, Amherst, MA, United States
| | - Tyler D. Bechtel
- Department of Food Science, University of Massachusetts, Amherst, MA, United States
| | - John G. Gibbons
- Department of Food Science, University of Massachusetts, Amherst, MA, United States
| | - Lynne McLandsborough
- Department of Food Science, University of Massachusetts, Amherst, MA, United States
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Stojowska-Swędrzyńska K, Kuczyńska-Wiśnik D, Laskowska E. New Strategies to Kill Metabolically-Dormant Cells Directly Bypassing the Need for Active Cellular Processes. Antibiotics (Basel) 2023; 12:1044. [PMID: 37370363 DOI: 10.3390/antibiotics12061044] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2023] [Revised: 06/09/2023] [Accepted: 06/11/2023] [Indexed: 06/29/2023] Open
Abstract
Antibiotic therapy failure is often caused by the presence of persister cells, which are metabolically-dormant bacteria capable of surviving exposure to antimicrobials. Under favorable conditions, persisters can resume growth leading to recurrent infections. Moreover, several studies have indicated that persisters may promote the evolution of antimicrobial resistance and facilitate the selection of specific resistant mutants; therefore, in light of the increasing numbers of multidrug-resistant infections worldwide, developing efficient strategies against dormant cells is of paramount importance. In this review, we present and discuss the efficacy of various agents whose antimicrobial activity is independent of the metabolic status of the bacteria as they target cell envelope structures. Since the biofilm-environment is favorable for the formation of dormant subpopulations, anti-persister strategies should also include agents that destroy the biofilm matrix or inhibit biofilm development. This article reviews examples of selected cell wall hydrolases, polysaccharide depolymerases and antimicrobial peptides. Their combination with standard antibiotics seems to be the most promising approach in combating persistent infections.
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Affiliation(s)
- Karolina Stojowska-Swędrzyńska
- Department of General and Medical Biochemistry, Faculty of Biology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland
| | - Dorota Kuczyńska-Wiśnik
- Department of General and Medical Biochemistry, Faculty of Biology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland
| | - Ewa Laskowska
- Department of General and Medical Biochemistry, Faculty of Biology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland
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Sherman ME, Smith RD, Gardner FM, Goodlett DR, Ernst RK. A Sensitive GC-MS Method for Quantitation of Lipid A Backbone Components and Terminal Phosphate Modifications. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2022; 33:2301-2309. [PMID: 36326685 PMCID: PMC9933694 DOI: 10.1021/jasms.2c00266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Lipid A, the hydrophobic anchor of lipopolysaccharide (LPS) present in the outer membrane of Gram-negative bacteria, serves as a target for cationic antimicrobial peptides, such as polymyxins. Membrane stress from polymyxins results in activation of two-component regulatory systems that produce lipid A modifying enzymes. These enzymes add neutral moieties, such as aminoarabinose (AraN) and ethanolamine (EtN) to lipid A terminal phosphates that mask the phosphate's negative charge and inhibit electrostatic interaction with the cationic polymyxins. Currently, these modifications may be detected by MALDI-TOF MS; however, this analysis is only semiquantitative. Herein we describe a GC-MS method to quantitate lipid A backbone components, glucosamine (GlcN) and inorganic phosphate (Pi), along with terminal phosphate modifications AraN and EtN. In this assay, lipid A is isolated from Gram-negative bacterial samples, hydrolyzed into its individual moieties, and derivatized via methoximation followed by silylation prior to analysis via GC-MS. Changes in AraN and EtN quantity were characterized using a variety of regulatory mutants of Salmonella, revealing differences that were not detected using MALDI-TOF MS analysis. Additionally, an increase in the abundance of AraN and EtN modifications were observed when resistant Enterobacter and Escherichia coli strains were grown in the presence of colistin (polymyxin E). Lastly, increased levels of Pi were found in bisphosphorylated lipid A compared to monophosphorylated lipid A samples. Because lipid A modifications serve as indicators of polymyxin resistance in Gram-negative bacteria, this method provides the capacity to monitor polymyxin resistance by quantification of lipid A modification using GC-MS.
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Affiliation(s)
- Matthew E Sherman
- Department of Microbial Pathogenesis, University of Maryland─Baltimore, Baltimore, Maryland 21201, United States
| | - Richard D Smith
- Department of Microbial Pathogenesis, University of Maryland─Baltimore, Baltimore, Maryland 21201, United States
| | - Francesca M Gardner
- Department of Microbial Pathogenesis, University of Maryland─Baltimore, Baltimore, Maryland 21201, United States
| | - David R Goodlett
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
- University of Gdansk, International Centre for Cancer Vaccine Science, Gdansk, 80-210, Poland
| | - Robert K Ernst
- Department of Microbial Pathogenesis, University of Maryland─Baltimore, Baltimore, Maryland 21201, United States
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Zeczycki TN, Milton ME, Jung D, Thompson RJ, Jaimes FE, Hondros AD, Palethorpe S, Melander C, Cavanagh J. 2-Aminoimidazole Analogs Target PhoP Altering DNA Binding Activity and Affect Outer Membrane Stability in Gram-Negative Bacteria. Biochemistry 2022; 61:2948-2960. [DOI: 10.1021/acs.biochem.2c00560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Affiliation(s)
- Tonya N. Zeczycki
- Department of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, North Carolina27834, United States
| | - Morgan E. Milton
- Department of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, North Carolina27834, United States
| | - David Jung
- Agile Sciences Inc., 617 Hutton Street, Raleigh, North Carolina27606, United States
| | - Richele J. Thompson
- Department of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, North Carolina27834, United States
| | - Felicia E. Jaimes
- Department of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, North Carolina27834, United States
| | - Alexander D. Hondros
- Department of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, North Carolina27834, United States
| | - Samantha Palethorpe
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, North Carolina27834, United States
| | - Christian Melander
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana46556, United States
| | - John Cavanagh
- Department of Biochemistry and Molecular Biology, Brody School of Medicine, East Carolina University, Greenville, North Carolina27834, United States
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Shaw C, Hess M, Weimer BC. Two-component systems regulate bacterial virulence in response to the host gastrointestinal environment and metabolic cues. Virulence 2022; 13:1666-1680. [PMID: 36128741 PMCID: PMC9518994 DOI: 10.1080/21505594.2022.2127196] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
Two-component systems are ubiquitous signaling mechanisms in bacteria that enable intracellular changes from extracellular cues. These bacterial regulatory systems couple external stimuli to control genetic expression via an autophosphorylation cascade that transduces membrane signals to intracellular locations, thereby allowing bacteria to rapidly adapt to the changing environmental conditions. Well known to control basic cellular processes, it is evident that two-component systems also exercise control over virulence traits, such as motility, secretion systems, and stress responses that impact the complex cascade of networks that alter virulence traits. In the gastrointestinal system, cues for activation of virulence-related two-component systems include metal ions, host-derived metabolites, and gut conditions. The diversity and origin of these cues suggest that the host can exert control over enteric pathogenicity via regulation in the gastrointestinal system. With the rise in multi-drug resistant pathogens, the potential control of pathogenicity with host cues via two-component systems presents a potential alternative to antimicrobials. Though the signaling mechanism itself is well studied, to date there is no systematic review compiling the host-associated cues of two-component systems and virulence traits. This review highlights the direct link between the host gastrointestinal environment and pathogenicity by focusing on two-component systems that are associated with the genetic expression of virulence traits, and that are activated by host-derived cues. The direct link between the host gastrointestinal environment, metabolites, and pathogenicity established in this review both underscores the importance of host-derived cues on bacterial activity and presents an enticing therapeutic target in the fight against antimicrobial resistant pathogens.
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Affiliation(s)
- Claire Shaw
- Department of Animal Science, Systems Microbiology & Natural Products Laboratory, University of California, Davis, USA
| | - Matthias Hess
- Department of Animal Science, Systems Microbiology & Natural Products Laboratory, University of California, Davis, USA
| | - Bart C Weimer
- Department of Population Health and Reproduction, 100K Pathogen Genome Project, University of California, Davis, CA, USA
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Dawan J, Ahn J. Bacterial Stress Responses as Potential Targets in Overcoming Antibiotic Resistance. Microorganisms 2022; 10:microorganisms10071385. [PMID: 35889104 PMCID: PMC9322497 DOI: 10.3390/microorganisms10071385] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 07/03/2022] [Accepted: 07/08/2022] [Indexed: 12/23/2022] Open
Abstract
Bacteria can be adapted to adverse and detrimental conditions that induce general and specific responses to DNA damage as well as acid, heat, cold, starvation, oxidative, envelope, and osmotic stresses. The stress-triggered regulatory systems are involved in bacterial survival processes, such as adaptation, physiological changes, virulence potential, and antibiotic resistance. Antibiotic susceptibility to several antibiotics is reduced due to the activation of stress responses in cellular physiology by the stimulation of resistance mechanisms, the promotion of a resistant lifestyle (biofilm or persistence), and/or the induction of resistance mutations. Hence, the activation of bacterial stress responses poses a serious threat to the efficacy and clinical success of antibiotic therapy. Bacterial stress responses can be potential targets for therapeutic alternatives to antibiotics. An understanding of the regulation of stress response in association with antibiotic resistance provides useful information for the discovery of novel antimicrobial adjuvants and the development of effective therapeutic strategies to control antibiotic resistance in bacteria. Therefore, this review discusses bacterial stress responses linked to antibiotic resistance in Gram-negative bacteria and also provides information on novel therapies targeting bacterial stress responses that have been identified as potential candidates for the effective control of Gram-negative antibiotic-resistant bacteria.
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Affiliation(s)
- Jirapat Dawan
- Department of Biomedical Science, Kangwon National University, Chuncheon 24341, Gangwon, Korea;
| | - Juhee Ahn
- Department of Biomedical Science, Kangwon National University, Chuncheon 24341, Gangwon, Korea;
- Institute of Bioscience and Biotechnology, Kangwon National University, Chuncheon 24341, Gangwon, Korea
- Correspondence: ; Tel.: +82-33-250-6564
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Targeting the Holy Triangle of Quorum Sensing, Biofilm Formation, and Antibiotic Resistance in Pathogenic Bacteria. Microorganisms 2022; 10:microorganisms10061239. [PMID: 35744757 PMCID: PMC9228545 DOI: 10.3390/microorganisms10061239] [Citation(s) in RCA: 43] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Revised: 06/12/2022] [Accepted: 06/14/2022] [Indexed: 12/12/2022] Open
Abstract
Chronic and recurrent bacterial infections are frequently associated with the formation of biofilms on biotic or abiotic materials that are composed of mono- or multi-species cultures of bacteria/fungi embedded in an extracellular matrix produced by the microorganisms. Biofilm formation is, among others, regulated by quorum sensing (QS) which is an interbacterial communication system usually composed of two-component systems (TCSs) of secreted autoinducer compounds that activate signal transduction pathways through interaction with their respective receptors. Embedded in the biofilms, the bacteria are protected from environmental stress stimuli, and they often show reduced responses to antibiotics, making it difficult to eradicate the bacterial infection. Besides reduced penetration of antibiotics through the intricate structure of the biofilms, the sessile biofilm-embedded bacteria show reduced metabolic activity making them intrinsically less sensitive to antibiotics. Moreover, they frequently express elevated levels of efflux pumps that extrude antibiotics, thereby reducing their intracellular levels. Some efflux pumps are involved in the secretion of QS compounds and biofilm-related materials, besides being important for removing toxic substances from the bacteria. Some efflux pump inhibitors (EPIs) have been shown to both prevent biofilm formation and sensitize the bacteria to antibiotics, suggesting a relationship between these processes. Additionally, QS inhibitors or quenchers may affect antibiotic susceptibility. Thus, targeting elements that regulate QS and biofilm formation might be a promising approach to combat antibiotic-resistant biofilm-related bacterial infections.
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