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Yang X, Zeng J, Wang D, Zhou Q, Yu X, Wang Z, Bai T, Luan G, Xu Y. NagZ modulates the virulence of E. cloacae by acting through the gene of unknown function, ECL_03795. Virulence 2024; 15:2367652. [PMID: 38912723 PMCID: PMC11197897 DOI: 10.1080/21505594.2024.2367652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Accepted: 06/09/2024] [Indexed: 06/25/2024] Open
Abstract
β-N-acetylglucosaminidase (NagZ), a cytosolic glucosaminidase, plays a pivotal role in peptidoglycan recycling. Previous research demonstrated that NagZ knockout significantly eradicated AmpC-dependent β-lactam resistance in Enterobacter cloacae. However, NagZ's role in the virulence of E. cloacae remains unclear. Our study, incorporating data on mouse and Galleria mellonella larval mortality rates, inflammation markers, and histopathological examinations, revealed a substantial reduction in the virulence of E. cloacae following NagZ knockout. Transcriptome sequencing uncovered differential gene expression between NagZ knockout and wild-type strains, particularly in nucleotide metabolism pathways. Further investigation demonstrated that NagZ deletion led to a significant increase in cyclic diguanosine monophosphate (c-di-GMP) levels. Additionally, transcriptome sequencing and RT-qPCR confirmed significant differences in the expression of ECL_03795, a gene with an unknown function but speculated to be involved in c-di-GMP metabolism due to its EAL domain known for phosphodiesterase activity. Interestingly, in ECL_03795 knockout strains, a notable reduction in the virulence was observed, and virulence was rescued upon complementation with ECL_03795. Consequently, our study suggests that NagZ's function on virulence is partially mediated through the ECL_03795→c-di-GMP pathway, providing insight into the development of novel therapies and strongly supporting the interest in creating highly efficient NagZ inhibitors.
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Affiliation(s)
- Xianggui Yang
- Department of Laboratory Medicine, Clinical Medical College and the First Affiliated Hospital of Chengdu Medical College, Chengdu, Sichuan, China
| | - Jun Zeng
- Division of Pulmonary and Critical Care Medicine, Clinical Medical College and the First Affiliated Hospital of Chengdu Medical College, Chengdu, Sichuan, China
| | - Dan Wang
- Department of Laboratory Medicine, Clinical Medical College and the First Affiliated Hospital of Chengdu Medical College, Chengdu, Sichuan, China
| | - Qin Zhou
- Department of Laboratory Medicine, Clinical Medical College and the First Affiliated Hospital of Chengdu Medical College, Chengdu, Sichuan, China
| | - Xuejing Yu
- Department of Internal Medicine, Division of Cardiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Zhenguo Wang
- Department of Stomatology, Clinical Medical College and the First Affiliated Hospital of Chengdu Medical College, Chengdu, Sichuan, China
| | - Tingting Bai
- Department of Laboratory Medicine, Clinical Medical College and the First Affiliated Hospital of Chengdu Medical College, Chengdu, Sichuan, China
| | - Guangxin Luan
- Department of Laboratory Medicine, Clinical Medical College and the First Affiliated Hospital of Chengdu Medical College, Chengdu, Sichuan, China
| | - Ying Xu
- Department of Laboratory Medicine, Clinical Medical College and the First Affiliated Hospital of Chengdu Medical College, Chengdu, Sichuan, China
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Sendra E, Fernández-Muñoz A, Zamorano L, Oliver A, Horcajada JP, Juan C, Gómez-Zorrilla S. Impact of multidrug resistance on the virulence and fitness of Pseudomonas aeruginosa: a microbiological and clinical perspective. Infection 2024; 52:1235-1268. [PMID: 38954392 PMCID: PMC11289218 DOI: 10.1007/s15010-024-02313-x] [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: 03/22/2024] [Accepted: 05/30/2024] [Indexed: 07/04/2024]
Abstract
Pseudomonas aeruginosa is one of the most common nosocomial pathogens and part of the top emergent species associated with antimicrobial resistance that has become one of the greatest threat to public health in the twenty-first century. This bacterium is provided with a wide set of virulence factors that contribute to pathogenesis in acute and chronic infections. This review aims to summarize the impact of multidrug resistance on the virulence and fitness of P. aeruginosa. Although it is generally assumed that acquisition of resistant determinants is associated with a fitness cost, several studies support that resistance mutations may not be associated with a decrease in virulence and/or that certain compensatory mutations may allow multidrug resistance strains to recover their initial fitness. We discuss the interplay between resistance profiles and virulence from a microbiological perspective but also the clinical consequences in outcomes and the economic impact.
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Affiliation(s)
- Elena Sendra
- Infectious Diseases Service, Hospital del Mar, Infectious Pathology and Antimicrobials Research Group (IPAR), Hospital del Mar Research Institute, Universitat Autònoma de Barcelona (UAB), CEXS-Universitat Pompeu Fabra, Passeig Marítim 25-27, 08003, Barcelona, Spain
| | - Almudena Fernández-Muñoz
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Microbiology Department, University Hospital Son Espases, Crtra. Valldemossa 79, 07010, Palma, Spain
| | - Laura Zamorano
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Microbiology Department, University Hospital Son Espases, Crtra. Valldemossa 79, 07010, Palma, Spain
| | - Antonio Oliver
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Microbiology Department, University Hospital Son Espases, Crtra. Valldemossa 79, 07010, Palma, Spain
- Center for Biomedical Research in Infectious Diseases Network (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain
| | - Juan Pablo Horcajada
- Infectious Diseases Service, Hospital del Mar, Infectious Pathology and Antimicrobials Research Group (IPAR), Hospital del Mar Research Institute, Universitat Autònoma de Barcelona (UAB), CEXS-Universitat Pompeu Fabra, Passeig Marítim 25-27, 08003, Barcelona, Spain
- Center for Biomedical Research in Infectious Diseases Network (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain
| | - Carlos Juan
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Microbiology Department, University Hospital Son Espases, Crtra. Valldemossa 79, 07010, Palma, Spain.
- Center for Biomedical Research in Infectious Diseases Network (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain.
| | - Silvia Gómez-Zorrilla
- Infectious Diseases Service, Hospital del Mar, Infectious Pathology and Antimicrobials Research Group (IPAR), Hospital del Mar Research Institute, Universitat Autònoma de Barcelona (UAB), CEXS-Universitat Pompeu Fabra, Passeig Marítim 25-27, 08003, Barcelona, Spain.
- Center for Biomedical Research in Infectious Diseases Network (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain.
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Qiu Z, Yuan K, Cao H, Chen S, Chen F, Mo F, Guo G, Peng J. Cross-talk of MLST and transcriptome unveiling antibiotic resistance mechanism of carbapenem resistance Acinetobacter baumannii clinical strains isolated in Guiyang, China. Front Microbiol 2024; 15:1394775. [PMID: 38946905 PMCID: PMC11211267 DOI: 10.3389/fmicb.2024.1394775] [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: 03/02/2024] [Accepted: 05/23/2024] [Indexed: 07/02/2024] Open
Abstract
Introduction Acinetobacter baumannii (A. baumannii) is an important opportunistic pathogen causing nosocomial infection in the clinic. The occurrence rate of antibiotic resistance is increasing year by year, resulting in a highly serious situation of bacterial resistance. Methods To better understand the local epidemiology of multidrug-resistant A. baumannii, an investigation was conducted on the antibiotic resistance of different types of A. baumannii and its relationship with the genes of A. baumannii. Furthermore, the molecular mechanism underlying antibiotic resistance in A. baumannii was investigated through transcriptome analysis. Results These results showed that a total of 9 STs were detected. It was found that 99% of the strains isolated in the hospital belonged to the same STs, and the clone complex CC208 was widely distributed in various departments and all kinds of samples. Furthermore, these A. baumannii strains showed high resistance to ertapenem, biapenem, meropenem, and imipenem, among which the resistance to ertapenem was the strongest. The detection rate of bla OXA-51 gene in these carbapenem resistance A. baumannii (CRAB) reached 100%; Additionally, the transcriptome results showed that the resistance genes were up-regulated in resistance strains, and these genes involved in biofilm formation, efflux pumps, peptidoglycan biosynthesis, and chaperonin synthesis. Discussion These results suggest that the CC208 STs were the main clonal complex, and showed high carbapenem antibiotic resistance. All these resistant strains were distributed in various departments, but most of them were distributed in intensive care units (ICU). The bla OXA-23 was the main antibiotic resistance genotype; In summary, the epidemic trend of clinical A. baumannii in Guiyang, China was analyzed from the molecular level, and the resistance mechanism of A. baumannii to carbapenem antibiotics was analyzed with transcriptome, which provided a theoretical basis for better control of A. baumannii.
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Affiliation(s)
- Zhilang Qiu
- Center for Clinical Laboratories, The Affiliated Hospital of Guizhou Medical University, Guiyang, China
- Key Laboratory of Infectious Immune and Antibody Engineering of Guizhou Province, Cellular Immunotherapy Engineering Research Center of Guizhou Province, School of Biology and Engineering/School of Basic Medical Sciences, Guizhou Medical University, Guiyang, China
- The Key and Characteristic Laboratory of Modern Pathogen Biology, Basic Medical College, Guizhou Medical University, Guiyang, China
| | - Kexin Yuan
- Center for Clinical Laboratories, The Affiliated Hospital of Guizhou Medical University, Guiyang, China
- The Key and Characteristic Laboratory of Modern Pathogen Biology, Basic Medical College, Guizhou Medical University, Guiyang, China
| | - Huijun Cao
- Center for Clinical Laboratories, The Affiliated Hospital of Guizhou Medical University, Guiyang, China
| | - Sufang Chen
- Key Laboratory of Infectious Immune and Antibody Engineering of Guizhou Province, Cellular Immunotherapy Engineering Research Center of Guizhou Province, School of Biology and Engineering/School of Basic Medical Sciences, Guizhou Medical University, Guiyang, China
- The Key and Characteristic Laboratory of Modern Pathogen Biology, Basic Medical College, Guizhou Medical University, Guiyang, China
| | - Feifei Chen
- Key Laboratory of Infectious Immune and Antibody Engineering of Guizhou Province, Cellular Immunotherapy Engineering Research Center of Guizhou Province, School of Biology and Engineering/School of Basic Medical Sciences, Guizhou Medical University, Guiyang, China
| | - Fei Mo
- Center for Clinical Laboratories, The Affiliated Hospital of Guizhou Medical University, Guiyang, China
| | - Guo Guo
- The Key and Characteristic Laboratory of Modern Pathogen Biology, Basic Medical College, Guizhou Medical University, Guiyang, China
- Translational Medicine Research Center, Guizhou Medical University, Guiyang, China
| | - Jian Peng
- Center for Clinical Laboratories, The Affiliated Hospital of Guizhou Medical University, Guiyang, China
- Key Laboratory of Infectious Immune and Antibody Engineering of Guizhou Province, Cellular Immunotherapy Engineering Research Center of Guizhou Province, School of Biology and Engineering/School of Basic Medical Sciences, Guizhou Medical University, Guiyang, China
- The Key and Characteristic Laboratory of Modern Pathogen Biology, Basic Medical College, Guizhou Medical University, Guiyang, China
- Translational Medicine Research Center, Guizhou Medical University, Guiyang, China
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Barceló IM, Escobar-Salom M, Cabot G, Perelló-Bauzà P, Jordana-Lluch E, Taltavull B, Torrens G, Rojo-Molinero E, Zamorano L, Pérez A, Oliver A, Juan C. Transferable AmpCs in Klebsiella pneumoniae: interplay with peptidoglycan recycling, mechanisms of hyperproduction, and virulence implications. Antimicrob Agents Chemother 2024; 68:e0131523. [PMID: 38517189 PMCID: PMC11064642 DOI: 10.1128/aac.01315-23] [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: 10/09/2023] [Accepted: 02/29/2024] [Indexed: 03/23/2024] Open
Abstract
Chromosomal and transferable AmpC β-lactamases represent top resistance mechanisms in different gram-negatives, but knowledge regarding the latter, mostly concerning regulation and virulence-related implications, is far from being complete. To fill this gap, we used Klebsiella pneumoniae (KP) and two different plasmid-encoded AmpCs [DHA-1 (AmpR regulator linked, inducible) and CMY-2 (constitutive)] as models to perform a study in which we show that blockade of peptidoglycan recycling through AmpG permease inactivation abolished DHA-1 inducibility but did not affect CMY-2 production and neither did it alter KP pathogenic behavior. Moreover, whereas regular production of both AmpC-type enzymes did not attenuate KP virulence, when blaDHA-1 was expressed in an ampG-defective mutant, Galleria mellonella killing was significantly (but not drastically) attenuated. Spontaneous DHA-1 hyperproducer mutants were readily obtained in vitro, showing slight or insignificant virulence attenuations together with high-level resistance to β-lactams only mildly affected by basal production (e.g., ceftazidime, ceftolozane/tazobactam). By analyzing diverse DHA-1-harboring clinical KP strains, we demonstrate that the natural selection of these hyperproducers is not exceptional (>10% of the collection), whereas mutational inactivation of the typical AmpC hyperproduction-related gene mpl was the most frequent underlying mechanism. The potential silent dissemination of this kind of strains, for which an important fitness cost-related contention barrier does not seem to exist, is envisaged as a neglected threat for most β-lactams effectiveness, including recently introduced combinations. Analyzing whether this phenomenon is applicable to other transferable β-lactamases and species as well as determining the levels of conferred resistance poses an essential topic to be addressed.IMPORTANCEAlthough there is solid knowledge about the regulation of transferable and especially chromosomal AmpC β-lactamases in Enterobacterales, there are still gaps to fill, mainly related to regulatory mechanisms and virulence interplays of the former. This work addresses them using Klebsiella pneumoniae as model, delving into a barely explored conception: the acquisition of a plasmid-encoded inducible AmpC-type enzyme whose production can be increased through selection of chromosomal mutations, entailing dramatically increased resistance compared to basal expression but minor associated virulence costs. Accordingly, we demonstrate that clinical K. pneumoniae DHA-1 hyperproducer strains are not exceptional. Through this study, we warn for the first time that this phenomenon may be a neglected new threat for β-lactams effectiveness (including some recently introduced ones) silently spreading in the clinical context, not only in K. pneumoniae but potentially also in other pathogens. These facts must be carefully considered in order to design future resistance-preventive strategies.
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Affiliation(s)
- Isabel M. Barceló
- Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases (HUSE), Palma, Spain
- Centro de Investigación Biomédica en Red, Área Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Maria Escobar-Salom
- Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases (HUSE), Palma, Spain
- Centro de Investigación Biomédica en Red, Área Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Gabriel Cabot
- Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases (HUSE), Palma, Spain
- Centro de Investigación Biomédica en Red, Área Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Pau Perelló-Bauzà
- Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
| | - Elena Jordana-Lluch
- Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases (HUSE), Palma, Spain
- Centro de Investigación Biomédica en Red, Área Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Biel Taltavull
- Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases (HUSE), Palma, Spain
- Centro de Investigación Biomédica en Red, Área Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Gabriel Torrens
- Department of Molecular Biology and Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden
| | - Estrella Rojo-Molinero
- Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases (HUSE), Palma, Spain
- Centro de Investigación Biomédica en Red, Área Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Laura Zamorano
- Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases (HUSE), Palma, Spain
- Centro de Investigación Biomédica en Red, Área Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Astrid Pérez
- National Center for Microbiology, Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Antonio Oliver
- Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases (HUSE), Palma, Spain
- Centro de Investigación Biomédica en Red, Área Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Carlos Juan
- Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases (HUSE), Palma, Spain
- Centro de Investigación Biomédica en Red, Área Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
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5
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Barceló IM, Escobar-Salom M, Jordana-Lluch E, Torrens G, Oliver A, Juan C. Filling knowledge gaps related to AmpC-dependent β-lactam resistance in Enterobacter cloacae. Sci Rep 2024; 14:189. [PMID: 38167986 PMCID: PMC10762043 DOI: 10.1038/s41598-023-50685-1] [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: 11/17/2023] [Accepted: 12/22/2023] [Indexed: 01/05/2024] Open
Abstract
Enterobacter cloacae starred different pioneer studies that enabled the development of a widely accepted model for the peptidoglycan metabolism-linked regulation of intrinsic class C cephalosporinases, highly conserved in different Gram-negatives. However, some mechanistic and fitness/virulence-related aspects of E. cloacae choromosomal AmpC-dependent resistance are not completely understood. The present study including knockout mutants, β-lactamase cloning, gene expression analysis, characterization of resistance phenotypes, and the Galleria mellonella infection model fills these gaps demonstrating that: (i) AmpC enzyme does not show any collateral activity impacting fitness/virulence; (ii) AmpC hyperproduction mediated by ampD inactivation does not entail any biological cost; (iii) alteration of peptidoglycan recycling alone or combined with AmpC hyperproduction causes no attenuation of E. cloacae virulence in contrast to other species; (iv) derepression of E. cloacae AmpC does not follow a stepwise dynamics linked to the sequential inactivation of AmpD amidase homologues as happens in Pseudomonas aeruginosa; (v) the enigmatic additional putative AmpC-type β-lactamase generally present in E. cloacae does not contribute to the classical cephalosporinase hyperproduction-based resistance, having a negligible impact on phenotypes even when hyperproduced from multicopy vector. This study reveals interesting particularities in the chromosomal AmpC-related behavior of E. cloacae that complete the knowledge on this top resistance mechanism.
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Affiliation(s)
- Isabel M Barceló
- Health Research Institute of the Balearic Islands (IdISBa), 07010, Palma, Spain
- Microbiology Department, University Hospital Son Espases (HUSE), 07010, Palma, Spain
- Centro de Investigación Biomédica en Red, Área Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - María Escobar-Salom
- Health Research Institute of the Balearic Islands (IdISBa), 07010, Palma, Spain
- Microbiology Department, University Hospital Son Espases (HUSE), 07010, Palma, Spain
- Centro de Investigación Biomédica en Red, Área Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - Elena Jordana-Lluch
- Health Research Institute of the Balearic Islands (IdISBa), 07010, Palma, Spain
- Microbiology Department, University Hospital Son Espases (HUSE), 07010, Palma, Spain
- Centro de Investigación Biomédica en Red, Área Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - Gabriel Torrens
- Department of Molecular Biology and Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Centre for Microbial Research (UCMR), Umeå University, 901 87, Umeå, Sweden
| | - Antonio Oliver
- Health Research Institute of the Balearic Islands (IdISBa), 07010, Palma, Spain
- Microbiology Department, University Hospital Son Espases (HUSE), 07010, Palma, Spain
- Centro de Investigación Biomédica en Red, Área Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - Carlos Juan
- Health Research Institute of the Balearic Islands (IdISBa), 07010, Palma, Spain.
- Microbiology Department, University Hospital Son Espases (HUSE), 07010, Palma, Spain.
- Centro de Investigación Biomédica en Red, Área Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, 28029, Madrid, Spain.
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Jordana-Lluch E, Barceló IM, Escobar-Salom M, Estévez MA, Zamorano L, Gómez-Zorrilla S, Sendra E, Oliver A, Juan C. The balance between antibiotic resistance and fitness/virulence in Pseudomonas aeruginosa: an update on basic knowledge and fundamental research. Front Microbiol 2023; 14:1270999. [PMID: 37840717 PMCID: PMC10569695 DOI: 10.3389/fmicb.2023.1270999] [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: 08/01/2023] [Accepted: 09/15/2023] [Indexed: 10/17/2023] Open
Abstract
The interplay between antibiotic resistance and bacterial fitness/virulence has attracted the interest of researchers for decades because of its therapeutic implications, since it is classically assumed that resistance usually entails certain biological costs. Reviews on this topic revise the published data from a general point of view, including studies based on clinical strains or in vitro-evolved mutants in which the resistance phenotype is seen as a final outcome, i.e., a combination of mechanisms. However, a review analyzing the resistance/fitness balance from the basic research perspective, compiling studies in which the different resistance pathways and respective biological costs are individually approached, was missing. Here we cover this gap, specifically focusing on Pseudomonas aeruginosa, a pathogen that stands out because of its extraordinary capacity for resistance development and for which a considerable number of recent and particular data on the interplay with fitness/virulence have been released. The revised information, split into horizontally-acquired vs. mutation-driven resistance, suggests a great complexity and even controversy in the resistance-fitness/virulence balance in the acute infection context, with results ranging from high costs linked to certain pathways to others that are seemingly cost-free or even cases of resistance mechanisms contributing to increased pathogenic capacities. The elusive mechanistic basis for some enigmatic data, knowledge gaps, and possibilities for therapeutic exploitation are discussed. The information gathered suggests that resistance-fitness/virulence interplay may be a source of potential antipseudomonal targets and thus, this review poses the elementary first step for the future development of these strategies harnessing certain resistance-associated biological burdens.
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Affiliation(s)
- Elena Jordana-Lluch
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Department of Microbiology, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas (CIBERINFEC), Madrid, Spain
| | - Isabel Mª Barceló
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Department of Microbiology, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas (CIBERINFEC), Madrid, Spain
| | - María Escobar-Salom
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Department of Microbiology, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas (CIBERINFEC), Madrid, Spain
| | - Miguel A. Estévez
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Department of Microbiology, University Hospital Son Espases, Palma, Spain
| | - Laura Zamorano
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Department of Microbiology, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas (CIBERINFEC), Madrid, Spain
| | - Silvia Gómez-Zorrilla
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas (CIBERINFEC), Madrid, Spain
- Infectious Diseases Service, Hospital del Mar, Hospital del Mar Research Institute, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Universitat Autònoma de Barcelóna (UAB), Barcelona, Spain
| | - Elena Sendra
- Infectious Diseases Service, Hospital del Mar, Hospital del Mar Research Institute, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Universitat Autònoma de Barcelóna (UAB), Barcelona, Spain
| | - Antonio Oliver
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Department of Microbiology, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas (CIBERINFEC), Madrid, Spain
| | - Carlos Juan
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Department of Microbiology, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas (CIBERINFEC), Madrid, Spain
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7
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Kadeřábková N, Mahmood AJS, Furniss RCD, Mavridou DAI. Making a chink in their armor: Current and next-generation antimicrobial strategies against the bacterial cell envelope. Adv Microb Physiol 2023; 83:221-307. [PMID: 37507160 PMCID: PMC10517717 DOI: 10.1016/bs.ampbs.2023.05.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/30/2023]
Abstract
Gram-negative bacteria are uniquely equipped to defeat antibiotics. Their outermost layer, the cell envelope, is a natural permeability barrier that contains an array of resistance proteins capable of neutralizing most existing antimicrobials. As a result, its presence creates a major obstacle for the treatment of resistant infections and for the development of new antibiotics. Despite this seemingly impenetrable armor, in-depth understanding of the cell envelope, including structural, functional and systems biology insights, has promoted efforts to target it that can ultimately lead to the generation of new antibacterial therapies. In this article, we broadly overview the biology of the cell envelope and highlight attempts and successes in generating inhibitors that impair its function or biogenesis. We argue that the very structure that has hampered antibiotic discovery for decades has untapped potential for the design of novel next-generation therapeutics against bacterial pathogens.
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Affiliation(s)
- Nikol Kadeřábková
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, United States
| | - Ayesha J S Mahmood
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, United States
| | - R Christopher D Furniss
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Despoina A I Mavridou
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, United States; John Ring LaMontagne Center for Infectious Diseases, The University of Texas at Austin, Austin, TX, United States.
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Escobar-Salom M, Barceló IM, Jordana-Lluch E, Torrens G, Oliver A, Juan C. Bacterial virulence regulation through soluble peptidoglycan fragments sensing and response: knowledge gaps and therapeutic potential. FEMS Microbiol Rev 2023; 47:fuad010. [PMID: 36893807 PMCID: PMC10039701 DOI: 10.1093/femsre/fuad010] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 02/10/2023] [Accepted: 03/07/2023] [Indexed: 03/11/2023] Open
Abstract
Given the growing clinical-epidemiological threat posed by the phenomenon of antibiotic resistance, new therapeutic options are urgently needed, especially against top nosocomial pathogens such as those within the ESKAPE group. In this scenario, research is pushed to explore therapeutic alternatives and, among these, those oriented toward reducing bacterial pathogenic power could pose encouraging options. However, the first step in developing these antivirulence weapons is to find weak points in the bacterial biology to be attacked with the goal of dampening pathogenesis. In this regard, during the last decades some studies have directly/indirectly suggested that certain soluble peptidoglycan-derived fragments display virulence-regulatory capacities, likely through similar mechanisms to those followed to regulate the production of several β-lactamases: binding to specific transcriptional regulators and/or sensing/activation of two-component systems. These data suggest the existence of intra- and also intercellular peptidoglycan-derived signaling capable of impacting bacterial behavior, and hence likely exploitable from the therapeutic perspective. Using the well-known phenomenon of peptidoglycan metabolism-linked β-lactamase regulation as a starting point, we gather and integrate the studies connecting soluble peptidoglycan sensing with fitness/virulence regulation in Gram-negatives, dissecting the gaps in current knowledge that need filling to enable potential therapeutic strategy development, a topic which is also finally discussed.
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Affiliation(s)
- María Escobar-Salom
- Research Unit and Microbiology Department, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Crtra. Valldemossa 79, 07010 Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas (CIBERINFEC). Av. Monforte de Lemos 3-5, 28029, Madrid, Spain
| | - Isabel María Barceló
- Research Unit and Microbiology Department, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Crtra. Valldemossa 79, 07010 Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas (CIBERINFEC). Av. Monforte de Lemos 3-5, 28029, Madrid, Spain
| | - Elena Jordana-Lluch
- Research Unit and Microbiology Department, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Crtra. Valldemossa 79, 07010 Palma, Spain
| | - Gabriel Torrens
- Research Unit and Microbiology Department, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Crtra. Valldemossa 79, 07010 Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas (CIBERINFEC). Av. Monforte de Lemos 3-5, 28029, Madrid, Spain
- Department of Molecular Biology and Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Centre for Microbial Research (UCMR), Umeå University. Försörjningsvägen 2A, SE-901 87 Umeå, Sweden
| | - Antonio Oliver
- Research Unit and Microbiology Department, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Crtra. Valldemossa 79, 07010 Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas (CIBERINFEC). Av. Monforte de Lemos 3-5, 28029, Madrid, Spain
| | - Carlos Juan
- Research Unit and Microbiology Department, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Crtra. Valldemossa 79, 07010 Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas (CIBERINFEC). Av. Monforte de Lemos 3-5, 28029, Madrid, Spain
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9
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Barceló IM, Jordana-Lluch E, Escobar-Salom M, Torrens G, Fraile-Ribot PA, Cabot G, Mulet X, Zamorano L, Juan C, Oliver A. Role of Enzymatic Activity in the Biological Cost Associated with the Production of AmpC β-Lactamases in Pseudomonas aeruginosa. Microbiol Spectr 2022; 10:e0270022. [PMID: 36214681 PMCID: PMC9604156 DOI: 10.1128/spectrum.02700-22] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 09/22/2022] [Indexed: 01/04/2023] Open
Abstract
In the current scenario of growing antibiotic resistance, understanding the interplay between resistance mechanisms and biological costs is crucial for designing therapeutic strategies. In this regard, intrinsic AmpC β-lactamase hyperproduction is probably the most important resistance mechanism of Pseudomonas aeruginosa, proven to entail important biological burdens that attenuate virulence mostly under peptidoglycan recycling alterations. P. aeruginosa can acquire resistance to new β-lactam-β-lactamase inhibitor combinations (ceftazidime-avibactam and ceftolozane-tazobactam) through mutations affecting ampC and its regulatory genes, but the impact of these mutations on the associated biological cost and the role that β-lactamase activity plays per se in contributing to the above-mentioned virulence attenuation are unknown. The same questions remain unsolved for plasmid-encoded AmpC-type β-lactamases such as FOX enzymes, some of which also provide resistance to new β-lactam-β-lactamase inhibitor combinations. Here, we assessed from different perspectives the effects of changes in the active center and, thus, in the hydrolytic spectrum resistance to inhibitors of AmpC-type β-lactamases on the fitness and virulence of P. aeruginosa, using site-directed mutagenesis; the previously described AmpC variants T96I, G183D, and ΔG229-E247; and, finally, blaFOX-4 versus blaFOX-8. Our results indicate the essential role of AmpC activity per se in causing the reported full virulence attenuation (in terms of growth, motility, cytotoxicity, and Galleria mellonella larvae killing), although the biological cost of the above-mentioned AmpC-type variants was similar to that of the wild-type enzymes. This suggests that there is not an important biological burden that may limit the selection/spread of these variants, which could progressively compromise the future effectiveness of the above-mentioned drug combinations. IMPORTANCE The growing antibiotic resistance of the top nosocomial pathogen Pseudomonas aeruginosa pushes research to explore new therapeutic strategies, for which the resistance-versus-virulence balance is a promising source of targets. While resistance often entails significant biological costs, little is known about the bases of the virulence attenuations associated with a resistance mechanism as extraordinarily relevant as β-lactamase production. We demonstrate that besides potential energy and cell wall alterations, the enzymatic activity of the P. aeruginosa cephalosporinase AmpC is essential for causing the full attenuation associated with its hyperproduction by affecting different features related to pathogenesis, a fact exploitable from the antivirulence perspective. Less encouraging, we also show that the production of different chromosomal/plasmid-encoded AmpC derivatives conferring resistance to some of the newest antibiotic combinations causes no significantly increased biological burdens, which suggests a free way for the selection/spread of these types of variants, potentially compromising the future effectiveness of these antipseudomonal therapies.
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Affiliation(s)
- Isabel M. Barceló
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas, Madrid, Spain
| | - Elena Jordana-Lluch
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases, Palma, Spain
| | - María Escobar-Salom
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas, Madrid, Spain
| | - Gabriel Torrens
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas, Madrid, Spain
- Department of Molecular Biology, Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden
- Laboratory for Molecular Infection Medicine Sweden, Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden
| | - Pablo A. Fraile-Ribot
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas, Madrid, Spain
| | - Gabriel Cabot
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas, Madrid, Spain
| | - Xavier Mulet
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas, Madrid, Spain
| | - Laura Zamorano
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas, Madrid, Spain
| | - Carlos Juan
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas, Madrid, Spain
| | - Antonio Oliver
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas, Madrid, Spain
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10
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Barceló IM, Torrens G, Escobar-Salom M, Jordana-Lluch E, Capó-Bauzá MM, Ramón-Pallín C, García-Cuaresma D, Fraile-Ribot PA, Mulet X, Oliver A, Juan C. Impact of Peptidoglycan Recycling Blockade and Expression of Horizontally Acquired β-Lactamases on Pseudomonas aeruginosa Virulence. Microbiol Spectr 2022; 10:e0201921. [PMID: 35171032 PMCID: PMC8849096 DOI: 10.1128/spectrum.02019-21] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 01/24/2022] [Indexed: 01/02/2023] Open
Abstract
In the current scenario of antibiotic resistance magnification, new weapons against top nosocomial pathogens like Pseudomonas aeruginosa are urgently needed. The interplay between β-lactam resistance and virulence is considered a promising source of targets to be attacked by antivirulence therapies, and in this regard, we previously showed that a peptidoglycan recycling blockade dramatically attenuated the pathogenic power of P. aeruginosa strains hyperproducing the chromosomal β-lactamase AmpC. Here, we sought to ascertain whether this observation could be applicable to other β-lactamases. To do so, P. aeruginosa wild-type or peptidoglycan recycling-defective strains (ΔampG and ΔnagZ) harboring different cloned β-lactamases (transferable GES, VIM, and OXA types) were used to assess their virulence in Galleria mellonella larvae by determining 50% lethal doses (LD50s). A mild yet significant LD50 increase was observed after peptidoglycan recycling disruption per se, whereas the expression of class A and B enzymes did not impact virulence. While the production of the narrow-spectrum class D OXA-2 entailed a slight attenuation, its extended-spectrum derivatives OXA-226 (W159R [bearing a change of W to R at position 159]), OXA-161 (N148D), and principally, OXA-539 (D149 duplication) were associated with outstanding virulence impairments, especially in recycling-defective backgrounds (with some LD50s being >1,000-fold that of the wild type). Although their exact molecular bases remain to be deciphered, these results suggest that mutations affecting the catalytic center and, therefore, the hydrolytic spectrum of OXA-2-derived enzymes also drastically impact the pathogenic power of P. aeruginosa. This work provides new and relevant knowledge to the complex topic of the interplay between the production of β-lactamases and virulence that could be useful to build future therapeutic strategies against P. aeruginosa. IMPORTANCE Pseudomonas aeruginosa is one of the leading nosocomial pathogens whose growing resistance makes the development of therapeutic options extremely urgent. The resistance-virulence interplay has classically aroused researchers' interest as a source of therapeutic targets. In this regard, we describe a wide array of virulence attenuations associated with different transferable β-lactamases, among which the production of OXA-2-derived extended-spectrum β-lactamases stood out as a dramatic handicap for pathogenesis, likely as a side effect of mutations causing the expansion of their hydrolytic spectrums. Moreover, our results confirm the validity of disturbing peptidoglycan recycling as a weapon to attenuate P. aeruginosa virulence in class C and D β-lactamase production backgrounds. In the current scenario of dissemination of horizontally acquired β-lactamases, this work brings out new data on the complex interplay between the production of specific enzymes and virulence attenuation that, if complemented with the characterization of the underlying mechanisms, will likely be exploitable to develop future virulence-targeting antipseudomonal strategies.
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Affiliation(s)
- Isabel M. Barceló
- Microbiology Department and Research Unit, University Hospital Son Espases, Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- CIBER de Enfermedades Infecciosas, Madrid, Spain
| | - Gabriel Torrens
- Microbiology Department and Research Unit, University Hospital Son Espases, Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- CIBER de Enfermedades Infecciosas, Madrid, Spain
| | - María Escobar-Salom
- Microbiology Department and Research Unit, University Hospital Son Espases, Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- CIBER de Enfermedades Infecciosas, Madrid, Spain
| | - Elena Jordana-Lluch
- Microbiology Department and Research Unit, University Hospital Son Espases, Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
| | - María Magdalena Capó-Bauzá
- Microbiology Department and Research Unit, University Hospital Son Espases, Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
| | - Carlos Ramón-Pallín
- Microbiology Department and Research Unit, University Hospital Son Espases, Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
| | - Daniel García-Cuaresma
- Microbiology Department and Research Unit, University Hospital Son Espases, Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
| | - Pablo A. Fraile-Ribot
- Microbiology Department and Research Unit, University Hospital Son Espases, Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- CIBER de Enfermedades Infecciosas, Madrid, Spain
| | - Xavier Mulet
- Microbiology Department and Research Unit, University Hospital Son Espases, Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- CIBER de Enfermedades Infecciosas, Madrid, Spain
| | - Antonio Oliver
- Microbiology Department and Research Unit, University Hospital Son Espases, Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- CIBER de Enfermedades Infecciosas, Madrid, Spain
| | - Carlos Juan
- Microbiology Department and Research Unit, University Hospital Son Espases, Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- CIBER de Enfermedades Infecciosas, Madrid, Spain
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11
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Escobar‐Salom M, Torrens G, Jordana‐Lluch E, Oliver A, Juan C. Mammals' humoral immune proteins and peptides targeting the bacterial envelope: from natural protection to therapeutic applications against multidrug‐resistant
Gram
‐negatives. Biol Rev Camb Philos Soc 2022; 97:1005-1037. [PMID: 35043558 PMCID: PMC9304279 DOI: 10.1111/brv.12830] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 12/12/2021] [Accepted: 12/15/2021] [Indexed: 12/11/2022]
Abstract
Mammalian innate immunity employs several humoral ‘weapons’ that target the bacterial envelope. The threats posed by the multidrug‐resistant ‘ESKAPE’ Gram‐negative pathogens (Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.) are forcing researchers to explore new therapeutic options, including the use of these immune elements. Here we review bacterial envelope‐targeting (peptidoglycan and/or membrane‐targeting) proteins/peptides of the mammalian immune system that are most likely to have therapeutic applications. Firstly we discuss their general features and protective activity against ESKAPE Gram‐negatives in the host. We then gather, integrate, and discuss recent research on experimental therapeutics harnessing their bactericidal power, based on their exogenous administration and also on the discovery of bacterial and/or host targets that improve the performance of this endogenous immunity, as a novel therapeutic concept. We identify weak points and knowledge gaps in current research in this field and suggest areas for future work to obtain successful envelope‐targeting therapeutic options to tackle the challenge of antimicrobial resistance.
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Affiliation(s)
- María Escobar‐Salom
- Department of Microbiology University Hospital Son Espases‐Health Research Institute of the Balearic Islands (IdISBa) Carretera de Valldemossa 79 Palma Balearic Islands 07010 Spain
| | - Gabriel Torrens
- Department of Microbiology University Hospital Son Espases‐Health Research Institute of the Balearic Islands (IdISBa) Carretera de Valldemossa 79 Palma Balearic Islands 07010 Spain
| | - Elena Jordana‐Lluch
- Department of Microbiology University Hospital Son Espases‐Health Research Institute of the Balearic Islands (IdISBa) Carretera de Valldemossa 79 Palma Balearic Islands 07010 Spain
| | - Antonio Oliver
- Department of Microbiology University Hospital Son Espases‐Health Research Institute of the Balearic Islands (IdISBa) Carretera de Valldemossa 79 Palma Balearic Islands 07010 Spain
| | - Carlos Juan
- Department of Microbiology University Hospital Son Espases‐Health Research Institute of the Balearic Islands (IdISBa) Carretera de Valldemossa 79 Palma Balearic Islands 07010 Spain
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12
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Yang X, Zeng J, Zhou Q, Yu X, Zhong Y, Wang F, Du H, Nie F, Pang X, Wang D, Fan Y, Bai T, Xu Y. Elevating NagZ Improves Resistance to β-Lactam Antibiotics via Promoting AmpC β-Lactamase in Enterobacter cloacae. Front Microbiol 2020; 11:586729. [PMID: 33250874 PMCID: PMC7672007 DOI: 10.3389/fmicb.2020.586729] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 10/02/2020] [Indexed: 11/13/2022] Open
Abstract
Enterobacter cloacae complex (ECC), one of the most common opportunistic pathogens causing multiple infections in human, is resistant to β-lactam antibiotics mainly due to its highly expressed chromosomal AmpC β-lactamase. It seems that regulation of chromosomal AmpC β-lactamase is associated with peptidoglycan recycling. However, underlying mechanisms are still poorly understood. In this study, we confirmed that NagZ, a glycoside hydrolase participating in peptidoglycan recycling in Gram-negative bacteria, plays a crucial role in developing resistance of E. cloacae (EC) to β-lactam antibiotics by promoting expression of chromosomal AmpC β-lactamase. Our data shows that NagZ was significantly up-regulated in resistant EC (resistant to at least one type of the third or fourth generation cephalosporins) compared to susceptible EC (susceptible to all types of the third and fourth generation cephalosporins). Similarly, the expression and β-lactamase activity of ampC were markedly enhanced in resistant EC. Moreover, ectopic expression of nagZ enhanced ampC expression and resistance to β-lactam antibiotics in susceptible EC. To further understand functions of NagZ in β-lactam resistance, nagZ-knockout EC model (ΔnagZ EC) was constructed by homologous recombination. Conversely, ampC mRNA and protein levels were down-regulated, and resistance to β-lactam antibiotics was attenuated in ΔnagZ EC, while specific complementation of nagZ was able to rescue ampC expression and resistance in ΔnagZ EC. More interestingly, NagZ and its hydrolyzates 1,6-anhydromuropeptides (anhMurNAc) could induce the expression of other target genes of AmpR (a global transcriptional factor), which suggested that the promotion of AmpC by NagZ is mediated AmpR activated by anhMurNAc in EC. In conclusion, these findings provide new elements for a better understanding of resistance in EC, which is crucial for the identification of novel potential drug targets.
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Affiliation(s)
- Xianggui Yang
- Department of Laboratory Medicine, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Jun Zeng
- Division of Pulmonary and Critical Care Medicine, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Qin Zhou
- Department of Laboratory Medicine, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Xuejing Yu
- Department of Cardiothoracic Surgery, University of Utah, Salt Lake City, UT, United States
| | - Yuanxiu Zhong
- Department of Biotechnology, Chengdu Medical College, Chengdu, China
| | - Fuying Wang
- Department of Cardiothoracic Surgery, University of Utah, Salt Lake City, UT, United States
| | - Hongfei Du
- Department of Laboratory Medicine, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Fang Nie
- Department of Laboratory Medicine, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Xueli Pang
- Department of Laboratory Medicine, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Dan Wang
- Department of Laboratory Medicine, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Yingzi Fan
- Department of Laboratory Medicine, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Tingting Bai
- Department of Laboratory Medicine, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Ying Xu
- Department of Laboratory Medicine, Clinical Medical College and The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
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13
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Torrens G, Escobar-Salom M, Oliver A, Juan C. Activity of mammalian peptidoglycan-targeting immunity against Pseudomonas aeruginosa. J Med Microbiol 2020; 69:492-504. [PMID: 32427563 DOI: 10.1099/jmm.0.001167] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Pseudomonas aeruginosa is one of the most important opportunistic pathogens, whose clinical relevance is not only due to the high morbidity/mortality of the infections caused, but also to its striking capacity for antibiotic resistance development. In the current scenario of a shortage of effective antipseudomonal drugs, it is essential to have thorough knowledge of the pathogen's biology from all sides, so as to find weak points for drug development. Obviously, one of these points could be the peptidoglycan, given its essential role for cell viability. Meanwhile, immune weapons targeting this structure could constitute an excellent model to be taken advantage of in order to design new therapeutic strategies. In this context, this review gathers all the information regarding the activity of mammalian peptidoglycan-targeting innate immunity (namely lysozyme and peptidoglycan recognition proteins), specifically against P. aeruginosa. All the published studies were considered, from both in vitro and in vivo fields, including works that envisage these weapons as options not only to potentiate their innate effects within the host or for use as exogenously administered treatments, but also harnessing their inflammatory and immune regulatory capacity to finally reduce damage in the patient. Altogether, this review has the objective of anticipating and discussing whether these innate immune resources, in combination or not with other drugs attacking certain P. aeruginosa targets leading to its increased sensitization, could be valid therapeutic antipseudomonal allies.
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Affiliation(s)
- Gabriel Torrens
- Servicio de Microbiología and Unidad de Investigación, Hospital Universitari Son Espases-Institut de Investigació Sanitària Illes Balears (IdISBa), Palma, Spain
| | - Maria Escobar-Salom
- Servicio de Microbiología and Unidad de Investigación, Hospital Universitari Son Espases-Institut de Investigació Sanitària Illes Balears (IdISBa), Palma, Spain
| | - Antonio Oliver
- Servicio de Microbiología and Unidad de Investigación, Hospital Universitari Son Espases-Institut de Investigació Sanitària Illes Balears (IdISBa), Palma, Spain
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14
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Dik DA, Kim C, Madukoma CS, Fisher JF, Shrout JD, Mobashery S. Fluorescence Assessment of the AmpR-Signaling Network of Pseudomonas aeruginosa to Exposure to β-Lactam Antibiotics. ACS Chem Biol 2020; 15:1184-1194. [PMID: 31990176 DOI: 10.1021/acschembio.9b00875] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Gram-negative bacteria have evolved an elaborate pathway to sense and respond to exposure to β-lactam antibiotics. The β-lactam antibiotics inhibit penicillin-binding proteins, whereby the loss of their activities alters/damages the cell-wall peptidoglycan. Bacteria sense this damage and remove the affected peptidoglycan into complex recycling pathways. As an offshoot of these pathways, muropeptide chemical signals generated from the cell-wall recycling manifest the production of a class C β-lactamase, which hydrolytically degrades the β-lactam antibiotic as a resistance mechanism. We disclose the use of a fluorescence probe that detects the activation of the recycling system by the formation of the key muropeptides involved in signaling. This same probe additionally detects natural-product cell-wall-active antibiotics that are produced in situ by cohabitating bacteria.
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Affiliation(s)
- David A. Dik
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Choon Kim
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Chinedu S. Madukoma
- Department of Civil & Environmental Engineering & Earth Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Jed F. Fisher
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Joshua D. Shrout
- Department of Civil & Environmental Engineering & Earth Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Shahriar Mobashery
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
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15
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Fisher JF, Mobashery S. Constructing and deconstructing the bacterial cell wall. Protein Sci 2020; 29:629-646. [PMID: 31747090 PMCID: PMC7021008 DOI: 10.1002/pro.3737] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 09/17/2019] [Accepted: 09/18/2019] [Indexed: 12/11/2022]
Abstract
The history of modern medicine cannot be written apart from the history of the antibiotics. Antibiotics are cytotoxic secondary metabolites that are isolated from Nature. The antibacterial antibiotics disproportionately target bacterial protein structure that is distinct from eukaryotic protein structure, notably within the ribosome and within the pathways for bacterial cell-wall biosynthesis (for which there is not a eukaryotic counterpart). This review focuses on a pre-eminent class of antibiotics-the β-lactams, exemplified by the penicillins and cephalosporins-from the perspective of the evolving mechanisms for bacterial resistance. The mechanism of action of the β-lactams is bacterial cell-wall destruction. In the monoderm (single membrane, Gram-positive staining) pathogen Staphylococcus aureus the dominant resistance mechanism is expression of a β-lactam-unreactive transpeptidase enzyme that functions in cell-wall construction. In the diderm (dual membrane, Gram-negative staining) pathogen Pseudomonas aeruginosa a dominant resistance mechanism (among several) is expression of a hydrolytic enzyme that destroys the critical β-lactam ring of the antibiotic. The key sensing mechanism used by P. aeruginosa is monitoring the molecular difference between cell-wall construction and cell-wall deconstruction. In both bacteria, the resistance pathways are manifested only when the bacteria detect the presence of β-lactams. This review summarizes how the β-lactams are sensed and how the resistance mechanisms are manifested, with the expectation that preventing these processes will be critical to future chemotherapeutic control of multidrug resistant bacteria.
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Affiliation(s)
- Jed F. Fisher
- Department of Chemistry and BiochemistryUniversity of Notre DameSouth BendIndiana
| | - Shahriar Mobashery
- Department of Chemistry and BiochemistryUniversity of Notre DameSouth BendIndiana
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