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Lin H, Song L, Zhou S, Fan C, Zhang M, Huang R, Zhou R, Qiu J, Ma S, He J. A Hybrid Antimicrobial Peptide Targeting Staphylococcus aureus with a Dual Function of Inhibiting Quorum Sensing Signaling and an Antibacterial Effect. J Med Chem 2023; 66:17105-17117. [PMID: 38099725 DOI: 10.1021/acs.jmedchem.3c02027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2023]
Abstract
Community-associated methicillin-resistant Staphylococcus aureus (MRSA) is now a major cause of bacterial infection. Antivirulence therapy does not stimulate evolution of a pathogen toward a resistant phenotype, providing a novel method to treat infectious diseases. Here, we used a cyclic peptide of CP7, an AIP-III variant that specifically inhibited the virulence and biofilm formation of Staphylococcus aureus (S. aureus) in a nonbiocidal manner, to conjugate with a broad-spectrum antimicrobial peptide (AMP) via two N-termini to obtain a hybrid AMP called CP7-FP13-2. This peptide not only specifically inhibited the production of virulence of S. aureus at low micromolar concentrations but also killed S. aureus, including MRSA, by disrupting the integrity of the bacterial cell membrane. In addition, CP7-FP13-2 inhibited the formation of the S. aureus biofilm and showed good antimicrobial efficacy against the S. aureus-infected Kunming mice model. Therefore, this study provides a promising strategy against the resistance and virulence of S. aureus.
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Affiliation(s)
- Haixing Lin
- Group of peptides and natural products Research, School of Pharmaceutical Sciences, Southern Medical University, 1838 Guangzhou Avenue North, Guangzhou 510515, P. R. China
- Department of Urology, Tongren Municipal People's Hospital, 120 Taoyuan Avenue, Tongren, Guizhou 554300, P. R. China
| | - Li Song
- Group of peptides and natural products Research, School of Pharmaceutical Sciences, Southern Medical University, 1838 Guangzhou Avenue North, Guangzhou 510515, P. R. China
| | - Shaofen Zhou
- Group of peptides and natural products Research, School of Pharmaceutical Sciences, Southern Medical University, 1838 Guangzhou Avenue North, Guangzhou 510515, P. R. China
| | - Cuiqiong Fan
- Group of peptides and natural products Research, School of Pharmaceutical Sciences, Southern Medical University, 1838 Guangzhou Avenue North, Guangzhou 510515, P. R. China
| | - Minna Zhang
- Department of Nephrology, Tongren Municipal People's Hospital, 120 Taoyuan Avenue, Tongren, Guizhou 554300, P. R. China
| | - Ruifeng Huang
- Group of peptides and natural products Research, School of Pharmaceutical Sciences, Southern Medical University, 1838 Guangzhou Avenue North, Guangzhou 510515, P. R. China
| | - Runhong Zhou
- Group of peptides and natural products Research, School of Pharmaceutical Sciences, Southern Medical University, 1838 Guangzhou Avenue North, Guangzhou 510515, P. R. China
| | - Jingnan Qiu
- Group of peptides and natural products Research, School of Pharmaceutical Sciences, Southern Medical University, 1838 Guangzhou Avenue North, Guangzhou 510515, P. R. China
| | - Shuaiqi Ma
- Group of peptides and natural products Research, School of Pharmaceutical Sciences, Southern Medical University, 1838 Guangzhou Avenue North, Guangzhou 510515, P. R. China
| | - Jian He
- Group of peptides and natural products Research, School of Pharmaceutical Sciences, Southern Medical University, 1838 Guangzhou Avenue North, Guangzhou 510515, P. R. China
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Jiang JH, Cameron DR, Nethercott C, Aires-de-Sousa M, Peleg AY. Virulence attributes of successful methicillin-resistant Staphylococcus aureus lineages. Clin Microbiol Rev 2023; 36:e0014822. [PMID: 37982596 PMCID: PMC10732075 DOI: 10.1128/cmr.00148-22] [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] [Indexed: 11/21/2023] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of severe and often fatal infections. MRSA epidemics have occurred in waves, whereby a previously successful lineage has been replaced by a more fit and better adapted lineage. Selection pressures in both hospital and community settings are not uniform across the globe, which has resulted in geographically distinct epidemiology. This review focuses on the mechanisms that trigger the establishment and maintenance of current, dominant MRSA lineages across the globe. While the important role of antibiotic resistance will be mentioned throughout, factors which influence the capacity of S. aureus to colonize and cause disease within a host will be the primary focus of this review. We show that while MRSA possesses a diverse arsenal of toxins including alpha-toxin, the success of a lineage involves more than just producing toxins that damage the host. Success is often attributed to the acquisition or loss of genetic elements involved in colonization and niche adaptation such as the arginine catabolic mobile element, as well as the activity of regulatory systems, and shift metabolism accordingly (e.g., the accessory genome regulator, agr). Understanding exactly how specific MRSA clones cause prolonged epidemics may reveal targets for therapies, whereby both core (e.g., the alpha toxin) and acquired virulence factors (e.g., the Panton-Valentine leukocidin) may be nullified using anti-virulence strategies.
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Affiliation(s)
- Jhih-Hang Jiang
- Department of Microbiology, Infection Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
- Department of Infectious Diseases, The Alfred Hospital and Central Clinical School, Monash University, Melbourne, Victoria, Australia
| | - David R. Cameron
- Department of Biomedical Research, University of Bern, Bern, Switzerland
| | - Cara Nethercott
- Department of Microbiology, Infection Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Marta Aires-de-Sousa
- Laboratory of Molecular Genetics, Institutode Tecnologia Químicae Biológica António Xavier (ITQB-NOVA), Universidade Nova de Lisboa, Oeiras, Portugal
- Escola Superior de Saúde da Cruz Vermelha Portuguesa-Lisboa (ESSCVP-Lisboa), Lisbon, Portugal
| | - Anton Y. Peleg
- Department of Microbiology, Infection Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
- Department of Infectious Diseases, The Alfred Hospital and Central Clinical School, Monash University, Melbourne, Victoria, Australia
- Centre to Impact Antimicrobial Resistance, Monash University, Clayton, Melbourne, Victoria, Australia
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3
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Cai H, Li X, Zhang C, Zhong H, Xie Y, Huang L, Zhang B, Long Y, Zhou Z, Liang B. Molecular characterisation of Staphylococcus aureus in school-age children in Guangzhou: associations among agr types, virulence genes, sequence types, and antibiotic resistant phenotypes. BMC Microbiol 2023; 23:368. [PMID: 38017399 PMCID: PMC10685675 DOI: 10.1186/s12866-023-03126-y] [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: 08/01/2023] [Accepted: 11/17/2023] [Indexed: 11/30/2023] Open
Abstract
BACKGROUND Staphylococcus aureus, one of the most prevalent opportunistic pathogens, mainly colonizes the nasal cavity and is a risk factor for severe infections. Virulence factors and accessory gene regulator (agr) are key to the severity and diversity of staphylococcal infection. In this study, we aimed to characterise S. aureus agr-types and virulence genes and correlated them with genetic background and antibiotic-resistant phenotypes. RESULTS Agr types were identified in 704 isolates (98.5%), with only 11 isolates were negative for agr type. Most of our isolates were classified as agr type I, followed by types III, II and IV. The enterotoxin c gene (sec) was detected in 48.6% of isolates, showing the highest prevalence among the five enterotoxin genes detected. The positivity rates for the lukS/F-PV and tsst genes were 4% and 2.2%, respectively, while neither sed nor SasX were detected. ST45, ST59, ST338, ST188, ST6, ST7, ST22, ST25, ST398, and ST944 belonged to agr I group, while ST5 and ST15 belonged to agr II group. ST30 and ST1 were classified into agr III group, and ST121 was assigned into agr IV group. The tsst gene was found exclusively within agr I and III types belonging to ST7 and ST30 isolates, while the lukS/F-PV was predominantly carried by agr I type isolates primarily within CC59 and CC22 clones. Among the methicillin-resistant S. aureus (MRSA) isolates, 89.7% belonged to agr I group, and 97.8% of rifampicin-resistant or intermediate isolates were assigned to agr I group. MRSA isolates harboured more tested virulence genes compared to methicillin-susceptible S. aureus isolates. CONCLUSIONS We characterized the distributions of agr types and eight major virulence genes of 715 S. aureus isolates, and our findings revealed clear associations between agr types and STs, as well as virulence genes, and drug resistant phenotypes.
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Affiliation(s)
- Hao Cai
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, People's Republic of China
| | - Xueying Li
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, People's Republic of China
| | - Chao Zhang
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, People's Republic of China
- Clinical Laboratory, Longgang District Maternity and Child Healthcare Hospital, Shenzhen, People's Republic of China
| | - Huamin Zhong
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, People's Republic of China
| | - Yongqiang Xie
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, People's Republic of China
| | - Lianfen Huang
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, People's Republic of China
| | - Baidu Zhang
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, People's Republic of China
| | - Yan Long
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, People's Republic of China
| | - Zhenwen Zhou
- National Clinical Laboratory on Tuberculosis, Beijing Key Laboratory for Drug-Resistant Tuberculosis Research, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Institute, Beijing, People's Republic of China.
| | - Bingshao Liang
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, People's Republic of China.
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In Silico Genome-Scale Analysis of Molecular Mechanisms Contributing to the Development of a Persistent Infection with Methicillin-Resistant Staphylococcus aureus (MRSA) ST239. Int J Mol Sci 2022; 23:ijms232416086. [PMID: 36555727 PMCID: PMC9781258 DOI: 10.3390/ijms232416086] [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: 10/30/2022] [Revised: 12/05/2022] [Accepted: 12/11/2022] [Indexed: 12/23/2022] Open
Abstract
The increasing frequency of isolation of methicillin-resistant Staphylococcus aureus (MRSA) limits the chances for the effective antibacterial therapy of staphylococcal diseases and results in the development of persistent infection such as bacteremia and osteomyelitis. The aim of this study was to identify features of the MRSAST239 0943-1505-2016 (SA943) genome that contribute to the formation of both acute and chronic musculoskeletal infections. The analysis was performed using comparative genomics data of the dominant epidemic S. aureus lineages, namely ST1, ST8, ST30, ST36, and ST239. The SA943 genome encodes proteins that provide resistance to the host's immune system, suppress immunological memory, and form biofilms. The molecular mechanisms of adaptation responsible for the development of persistent infection were as follows: amino acid substitution in PBP2 and PBP2a, providing resistance to ceftaroline; loss of a large part of prophage DNA and restoration of the nucleotide sequence of beta-hemolysin, that greatly facilitates the escape of phagocytosed bacteria from the phagosome and formation of biofilms; dysfunction of the AgrA system due to the presence of psm-mec and several amino acid substitutions in the AgrC; partial deletion of the nucleotide sequence in genomic island vSAβ resulting in the loss of two proteases of Spl-operon; and deletion of SD repeats in the SdrE amino acid sequence.
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Natural transformation allows transfer of SCCmec-mediated methicillin resistance in Staphylococcus aureus biofilms. Nat Commun 2022; 13:2477. [PMID: 35513365 PMCID: PMC9072672 DOI: 10.1038/s41467-022-29877-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 03/16/2022] [Indexed: 12/30/2022] Open
Abstract
SCCmec is a large mobile genetic element that includes the mecA gene and confers resistance to β-lactam antibiotics in methicillin-resistant Staphylococcus aureus (MRSA). There is evidence that SCCmec disseminates among staphylococci, but the transfer mechanisms are unclear. Here, we show that two-component systems mediate the upregulation of natural competence genes in S. aureus under biofilm growth conditions, and this enhances the efficiency of natural transformation. We observe SCCmec transfer via natural transformation from MRSA, and from methicillin-resistant coagulase-negative staphylococci, to methicillin-sensitive S. aureus. The process requires the SCCmec recombinase genes ccrAB, and the stability of the transferred SCCmec varies depending on SCCmec types and recipients. Our results suggest that natural transformation plays a role in the transfer of SCCmec and possibly other mobile genetic elements in S. aureus biofilms. SCCmec is a large mobile genetic element that confers resistance to β-lactam antibiotics in methicillin-resistant Staphylococcus aureus. Here, the authors show that biofilm growth conditions enhance the efficiency of natural transformation in S. aureus and allow the transfer of SCCmec to methicillin-sensitive strains.
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6
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Fan Q, Zuo J, Wang H, Grenier D, Yi L, Wang Y. Contribution of quorum sensing to virulence and antibiotic resistance in zoonotic bacteria. Biotechnol Adv 2022; 59:107965. [PMID: 35487393 DOI: 10.1016/j.biotechadv.2022.107965] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 04/15/2022] [Accepted: 04/21/2022] [Indexed: 11/02/2022]
Abstract
Quorum sensing (QS), which is a key part of cell/cell communication, is widely distributed in microorganisms, especially in bacteria. Bacteria can produce and detect the presence of QS signal molecule, perceive the composition and density of microorganisms in their complex habitat, and then dynamically regulate their own gene expression to adapt to their environment. Among the many traits controlled by QS in pathogenic bacteria is the expression of virulence factors and antibiotic resistance. Many pathogenic bacteria rely on QS to govern the production of virulence factors and express drug-resistance, especially in zoonotic bacteria. The threat of antibiotic resistant zoonotic bacteria has called for alternative antimicrobial strategies that would mitigate the increase of classical resistance mechanism. Targeting QS has proven to be a promising alternative to conventional antibiotic for controlling infections. Here we review the QS systems in common zoonotic pathogenic bacteria and outline how QS may control the virulence and antibiotic resistance of zoonotic bacteria.
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Affiliation(s)
- Qingying Fan
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China; Key Laboratory of Molecular Pathogen and Immunology of Animal of Luoyang, Luoyang, China
| | - Jing Zuo
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China; Key Laboratory of Molecular Pathogen and Immunology of Animal of Luoyang, Luoyang, China
| | - Haikun Wang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China; Key Laboratory of Molecular Pathogen and Immunology of Animal of Luoyang, Luoyang, China
| | - Daniel Grenier
- Groupe de Recherche en Écologie Buccale (GREB), Faculté de Médecine Dentaire, Université Laval, Quebec City, Canada
| | - Li Yi
- Key Laboratory of Molecular Pathogen and Immunology of Animal of Luoyang, Luoyang, China; College of Life Science, Luoyang Normal University, Luoyang, China.
| | - Yang Wang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China; Key Laboratory of Molecular Pathogen and Immunology of Animal of Luoyang, Luoyang, China.
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Montagut EJ, Acosta G, Albericio F, Royo M, Godoy-Tena G, Lacoma A, Prat C, Salvador JP, Marco MP. Direct Quantitative Immunochemical Analysis of Autoinducer Peptide IV for Diagnosing and Stratifying Staphylococcus aureus Infections. ACS Infect Dis 2022; 8:645-656. [PMID: 35175740 PMCID: PMC8922274 DOI: 10.1021/acsinfecdis.1c00670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An immunochemical strategy to detect and quantify AIP-IV, the quorum sensing (QS) signaling molecule produced by Staphylococcus aureus agr type IV, is reported here for the first time. Theoretical calculations and molecular modeling studies have assisted on the design and synthesis of a suitable peptide hapten (AIPIVS), allowing to obtain high avidity and specific antibodies toward this peptide despite its low molecular weight. The ELISA developed achieves an IC50 value of 2.80 ± 0.17 and an LOD of 0.19 ± 0.06 nM in complex media such as 1/2 Tryptic Soy Broth. Recognition of other S. aureus AIPs (I-III) is negligible (cross-reactivity below 0.001%), regardless of the structural similarities. A pilot study with a set of clinical isolates from patients with airways infection or colonization demonstrates the potential of this ELISA to perform biomedical investigations related to the role of QS in pathogenesis and the association between dysfunctional agr or the agr type with unfavorable clinical outcomes. The AIP-IV levels could be quantified in the low nanomolar range in less than 1 h after inoculating agr IV-genotyped isolates in the culture broth, while those genotyped as I-III did not show any immunoreactivity after a 48 h growth, pointing to the possibility to use this technology for phenotyping S. aureus. The research strategy here reported can be extended to the rest of the AIP types of S. aureus, allowing the development of powerful multiplexed chips or point-of-care (PoC) diagnostic devices to unequivocally identify its presence and its agr type on samples from infected patients.
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Affiliation(s)
- Enrique-J. Montagut
- Nanobiotechnology for Diagnostics (Nb4D), Department of Surfactants and Nanobiotechnology, Institute for Advanced Chemistry of Catalonia (IQAC) of the Spanish Council for Scientific Research (CSIC), 08750 Barcelona, Spain
- CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), 28029 Madrid Spain
| | - Gerardo Acosta
- CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), 28029 Madrid Spain
- Multivalent Systems for Nanomedicine (MS4N), Department of Surfactants and Nanobiotechnology, Institute for Advanced Chemistry of Catalonia (IQAC) of the Spanish Council for Scientific Research (CSIC), 08750 Barcelona, Spain
| | - Fernando Albericio
- CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), 28029 Madrid Spain
- Multivalent Systems for Nanomedicine (MS4N), Department of Surfactants and Nanobiotechnology, Institute for Advanced Chemistry of Catalonia (IQAC) of the Spanish Council for Scientific Research (CSIC), 08750 Barcelona, Spain
- Department of Organic Chemistry, Faculty of Chemistry, University of Barcelona, 08028 Barcelona, Spain
- School of Chemistry and Physics, University of KwaZulu-Natal, 4000 Durban, South Africa
| | - Miriam Royo
- CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), 28029 Madrid Spain
- Multivalent Systems for Nanomedicine (MS4N), Department of Surfactants and Nanobiotechnology, Institute for Advanced Chemistry of Catalonia (IQAC) of the Spanish Council for Scientific Research (CSIC), 08750 Barcelona, Spain
| | - Gerard Godoy-Tena
- Servei de Microbiologia, Hospital Universitari Germans Trias i Pujol, Institut d’Investigació Germans Trias i Pujol, Universitat Autònoma de Barcelona, 08916 Badalona, Spain
| | - Alicia Lacoma
- Servei de Microbiologia, Hospital Universitari Germans Trias i Pujol, Institut d’Investigació Germans Trias i Pujol, Universitat Autònoma de Barcelona, 08916 Badalona, Spain
- CIBER de Enfermedades Respiratorias (CIBERES), 28029 Madrid, Spain
| | - Cristina Prat
- Servei de Microbiologia, Hospital Universitari Germans Trias i Pujol, Institut d’Investigació Germans Trias i Pujol, Universitat Autònoma de Barcelona, 08916 Badalona, Spain
- CIBER de Enfermedades Respiratorias (CIBERES), 28029 Madrid, Spain
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, 3584 Utrecht, the Netherlands
| | - Juan-Pablo Salvador
- Nanobiotechnology for Diagnostics (Nb4D), Department of Surfactants and Nanobiotechnology, Institute for Advanced Chemistry of Catalonia (IQAC) of the Spanish Council for Scientific Research (CSIC), 08750 Barcelona, Spain
- CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), 28029 Madrid Spain
| | - María-Pilar Marco
- Nanobiotechnology for Diagnostics (Nb4D), Department of Surfactants and Nanobiotechnology, Institute for Advanced Chemistry of Catalonia (IQAC) of the Spanish Council for Scientific Research (CSIC), 08750 Barcelona, Spain
- CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), 28029 Madrid Spain
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Raghuram V, Alexander AM, Loo HQ, Petit RA, Goldberg JB, Read TD. Species-Wide Phylogenomics of the Staphylococcus aureus Agr Operon Revealed Convergent Evolution of Frameshift Mutations. Microbiol Spectr 2022; 10:e0133421. [PMID: 35044202 PMCID: PMC8768832 DOI: 10.1128/spectrum.01334-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 01/03/2022] [Indexed: 11/20/2022] Open
Abstract
Staphylococcus aureus is a prominent nosocomial pathogen that causes several life-threatening diseases, such as pneumonia and bacteremia. S. aureus modulates the expression of its arsenal of virulence factors through sensing and integrating responses to environmental signals. The agr (accessory gene regulator) quorum sensing (QS) system is a major regulator of virulence phenotypes in S. aureus. There are four agr specificity groups each with a different autoinducer peptide sequence encoded by the agrD gene. Although agr is critical for the expression of many toxins, paradoxically, S. aureus strains often have nonfunctional agr activity due to loss-of-function mutations in the four-gene agr operon. To understand patterns in agr variability across S. aureus, we undertook a species-wide genomic investigation. We developed a software tool (AgrVATE; https://github.com/VishnuRaghuram94/AgrVATE) for typing and detecting frameshift mutations in the agr operon. In an analysis of over 40,000 S. aureus genomes, we showed a close association between agr type and S. aureus clonal complex. We also found a strong linkage between agrBDC alleles (encoding the peptidase, autoinducing peptide itself, and peptide sensor, respectively) but not agrA (encoding the response regulator). More than 5% of the genomes were found to have frameshift mutations in the agr operon. While 52% of these frameshifts occurred only once in the entire species, we observed cases where the recurring mutations evolved convergently across different clonal lineages with no evidence of long-term phylogenetic transmission, suggesting that strains with agr frameshifts were evolutionarily short-lived. Overall, genomic analysis of agr operon suggests evolution through multiple processes with functional consequences that are not fully understood. IMPORTANCE Staphylococcus aureus is a globally pervasive pathogen that produces a plethora of toxic molecules that can harm host immune cells. Production of these toxins is mainly controlled by an active agr quorum-sensing system, which senses and responds to bacterial cell density. However, there are many reports of S. aureus strains with genetic changes leading to impaired agr activity that are often found during chronic bloodstream infections and may be associated with increased disease severity. We developed an open-source software called AgrVATE to type agr systems and identify mutations. We used AgrVATE for a species-wide genomic survey of S. aureus, finding that more than 5% of strains in the public database had nonfunctional agr systems. We also provided new insights into the evolution of these genetic mutations in the agr system. Overall, this study contributes to our understanding of a common but relatively understudied means of virulence regulation in S. aureus.
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Affiliation(s)
- Vishnu Raghuram
- Microbiology and Molecular Genetics Program, Graduate Division of Biological and Biomedical Sciences, Laney Graduate School, Emory University, Atlanta, Georgia, USA
| | - Ashley M. Alexander
- Population Biology, Ecology, and Evolution Program, Graduate Division of Biological and Biomedical Sciences, Laney Graduate School, Emory University, Atlanta, Georgia, USA
| | - Hui Qi Loo
- Department of Biology, Emory University, Atlanta, Georgia, USA
| | - Robert A. Petit
- Division of Infectious Diseases, Department of Medicine, Emory University, Atlanta, Georgia, USA
| | - Joanna B. Goldberg
- Division of Pulmonary, Allergy and Immunology, Cystic Fibrosis, and Sleep, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Timothy D. Read
- Division of Infectious Diseases, Department of Medicine, Emory University, Atlanta, Georgia, USA
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9
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The RD2 Pathogenicity Island Modifies the Disease Potential of the Group A Streptococcus. Infect Immun 2021; 89:e0072220. [PMID: 33820819 DOI: 10.1128/iai.00722-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Serotype M28 isolates of the group A Streptococcus (GAS; Streptococcus pyogenes) are nonrandomly associated with cases of puerperal sepsis, a potentially life-threatening infection that can occur in women following childbirth. Previously, we discovered that the 36.3-kb RD2 pathogenicity island, which is present in serotype M28 isolates but lacking from most other isolates, promotes the ability of M28 GAS to colonize the female reproductive tract. Here, we performed a gain-of-function study in which we introduced RD2 into representative serotype M1, M49, and M59 isolates and assessed the phenotypic consequences of RD2 acquisition. All RD2-containing derivatives colonized a higher percentage of mice, and at higher CFU levels, than did the parental isolates in a mouse vaginal colonization model. However, for two additional phenotypes, survival in heparinized whole human blood and adherence to two human vaginal epithelial cell lines, there were serotype-specific differences from RD2 acquisition. Using transcriptomic comparisons, we identified that such differences may be a consequence of RD2 altering the abundance of transcripts from select core genome genes along serotype-specific lines. Our study is the first that interrogates RD2 function in GAS serotypes other than M28 isolates, shedding light on variability in the phenotypic consequences of RD2 acquisition and informing on why this mobile genetic element is not ubiquitous in the GAS population.
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10
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Raineri EJM, Altulea D, van Dijl JM. Staphylococcal trafficking and infection - from 'nose to gut' and back. FEMS Microbiol Rev 2021; 46:6321165. [PMID: 34259843 PMCID: PMC8767451 DOI: 10.1093/femsre/fuab041] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Accepted: 07/11/2021] [Indexed: 12/12/2022] Open
Abstract
Staphylococcus aureus is an opportunistic human pathogen, which is a leading cause of infections worldwide. The challenge in treating S. aureus infection is linked to the development of multidrug-resistant strains and the mechanisms employed by this pathogen to evade the human immune defenses. In addition, S. aureus can hide asymptomatically in particular ‘protective’ niches of the human body for prolonged periods of time. In the present review, we highlight recently gained insights in the role of the human gut as an endogenous S. aureus reservoir next to the nasopharynx and oral cavity. In addition, we address the contribution of these ecological niches to staphylococcal transmission, including the roles of particular triggers as modulators of the bacterial dissemination. In this context, we present recent advances concerning the interactions between S. aureus and immune cells to understand their possible roles as vehicles of dissemination from the gut to other body sites. Lastly, we discuss the factors that contribute to the switch from colonization to infection. Altogether, we conclude that an important key to uncovering the pathogenesis of S. aureus infection lies hidden in the endogenous staphylococcal reservoirs, the trafficking of this bacterium through the human body and the subsequent immune responses.
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Affiliation(s)
- Elisa J M Raineri
- Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Dania Altulea
- Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Jan Maarten van Dijl
- Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
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11
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Nasser A, Dallal MMS, Jahanbakhshi S, Azimi T, Nikouei L. Staphylococcus aureus: biofilm formation and strategies against it. Curr Pharm Biotechnol 2021; 23:664-678. [PMID: 34238148 DOI: 10.2174/1389201022666210708171123] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 05/09/2021] [Accepted: 05/31/2021] [Indexed: 11/22/2022]
Abstract
The formation of Staphylococcus aureus biofilm causes significant infections in the human body. Biofilm forms through the aggregation of bacterial species and brings about many complications. It mediates drug resistance and persistence and facilitates the recurrence of infection at the end of antimicrobial therapy. Biofilm formation goes through a series of steps to complete, and any interference in these steps can disrupt its formation. Such interference may occur at any stage of biofilm production, including attachment, monolayer formation, and accumulation. Interfering agents can act as quorum sensing inhibitors and interfere in the functionality of quorum sensing receptors, attachment inhibitors and affect the cell hydrophobicity. Among these inhibiting strategies, attachment inhibitors could serve as the best agents against biofilm formation. If pathogens abort the attachment, the following stages of biofilm formation, e.g., accumulation and dispersion, will fail to materialize. Inhibition at this stage leads to suppression of virulence factors and invasion. One of the best-known inhibitors is a chelator that collects metal, Fe+, Zn+, and magnesium critical for biofilm formation. These influential factors in the binding and formation of biofilm are investigated, and the coping strategy is discussed. This review examines the stages of biofilm formation and determines what factors interfere in the continuity of these steps. Finally, the inhibition strategies are investigated, reviewed, and discussed. Keywords: Biofilm, Staphylococcus, Biofilm inhibitor, Dispersion, Antibiofilm agent, EPS, PIA.
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Affiliation(s)
- Ahmad Nasser
- Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | | | - Shiva Jahanbakhshi
- Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Taher Azimi
- Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Leila Nikouei
- Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
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12
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Sargison F, Goncheva MI, Alves J, Pickering A, Fitzgerald JR. Staphylococcus aureus secreted lipases do not inhibit innate immune killing mechanisms. Wellcome Open Res 2021; 5:286. [PMID: 33623827 PMCID: PMC7871421 DOI: 10.12688/wellcomeopenres.16194.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/16/2021] [Indexed: 11/20/2022] Open
Abstract
Background:Staphylococcus aureus causes an array of diseases in both humans and livestock. Pathogenesis is mediated by a plethora of proteins secreted by
S. aureus, many of which remain incompletely characterised. For example,
S. aureus abundantly secretes two isoforms of the enzyme lipase into the extracellular milieu, where they scavenge upon polymeric triglycerides. It has previously been suggested that lipases may interfere with the function of innate immune cells, such as macrophages and neutrophils, but the impact of lipases on phagocytic killing mechanisms remains unknown. Methods: We employed the epidemic
S. aureus clone USA300 strain LAC and its lipase deficient isogenic mutant, along with recombinant lipase proteins, in
in vitro experimental infection assays. To determine if lipases can inhibit innate immune killing mechanisms, the bactericidal activity of whole blood, human neutrophils, and macrophages was analysed. In addition, gentamycin protection assays were carried out to examine the influence of lipases on
S. aureus innate immune cell escape. Results: There were no differences in the survival of
S. aureus USA300 LAC wild type and its lipase-deficient isogenic mutant after incubation with human whole blood or neutrophils. Furthermore, there was no detectable lipase-dependent effect on phagocytosis, intracellular survival, or escape from both human primary and immortalised cell line macrophages, even upon supplementation with exogenous recombinant lipases. Conclusions: S. aureus lipases do not inhibit bacterial killing mechanisms of human macrophages, neutrophils, or whole blood. These findings broaden our understanding of the interaction of
S. aureus with the innate immune system.
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13
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Mould DL, Hogan DA. Intraspecies heterogeneity in microbial interactions. Curr Opin Microbiol 2021; 62:14-20. [PMID: 34034081 DOI: 10.1016/j.mib.2021.04.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 04/08/2021] [Accepted: 04/13/2021] [Indexed: 11/18/2022]
Abstract
Microbial interactions are increasingly recognized as an integral part of microbial physiology. Cell-cell communication mediated by quorum sensing and metabolite exchange is a formative element of microbial interactions. However, loss-of-function mutations in quorum-sensing components are common across diverse species. Furthermore, quorum sensing is modulated by small molecules and environmental conditions that may be altered in the presence of other microbial species. Recent evidence highlights how strain heterogeneity impacts microbial interactions. There is great potential for microbial interactions to act as selective pressures that influence the emergence of common mutations in quorum-sensing genes across the bacterial and fungal domains.
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Affiliation(s)
- Dallas L Mould
- Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Deborah A Hogan
- Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA.
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14
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Siegmund A, Afzal MA, Tetzlaff F, Keinhörster D, Gratani F, Paprotka K, Westermann M, Nietzsche S, Wolz C, Fraunholz M, Hübner CA, Löffler B, Tuchscherr L. Intracellular persistence of Staphylococcus aureus in endothelial cells is promoted by the absence of phenol-soluble modulins. Virulence 2021; 12:1186-1198. [PMID: 33843450 PMCID: PMC8043190 DOI: 10.1080/21505594.2021.1910455] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
A large proportion of clinical S. aureus isolates that carry an inactive Agr system are associated with persistent infection that is difficult to treat. Once S. aureus is inside the bloodstream, it can cross the endothelial barrier and invade almost every organ in the human body. Endothelial cells can either be lysed by this pathogen or they serve as a niche for its intracellular long-term survival. Following phagocytosis, several vesicles such as phagosomes and autophagosomes, target intracellular S. aureus for elimination. S. aureus can escape from these vesicles into the host cytoplasm through the activation of phenol-soluble modulins (PSMs) αβ. Thereafter, it replicates and lyses the host cell to disseminate to adjacent tissues. Herein we demonstrate that staphylococcal strains which lack the expression of PSMs employ an alternative pathway to better persist within endothelial cells. The intracellular survival of S. aureus is associated with the co-localization of the autophagy marker LC3. In cell culture infection models, we found that the absence of psmαβ decreased the host cell lysis and increased staphylococcal long-term survival. This study explains the positive selection of agr-negative strains that lack the expression of psmαβ in chronic infection due to their advantage in surviving and evading the clearance system of the host.
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Affiliation(s)
- Anke Siegmund
- Institute of Medical Microbiology, Jena University Hospital, Jena, Germany
| | - Muhammad Awais Afzal
- Institute of Human Genetics, Jena University Hospital, Friedrich Schiller Universität, Jena, Germany
| | - Felix Tetzlaff
- Institute of Human Genetics, Jena University Hospital, Friedrich Schiller Universität, Jena, Germany
| | - Daniela Keinhörster
- Interfaculty Institute for Microbiology and Infection Medicine Tübingen, Tübingen, Germany
| | - Fabio Gratani
- Interfaculty Institute for Microbiology and Infection Medicine Tübingen, Tübingen, Germany
| | - Kerstin Paprotka
- Biocenter, Chair of Microbiology, University of Würzburg, Würzburg, Germany
| | - Martin Westermann
- Center for Electron Microscopy, Jena University Hospital, Jena, Germany
| | - Sandor Nietzsche
- Center for Electron Microscopy, Jena University Hospital, Jena, Germany
| | - Christiane Wolz
- Interfaculty Institute for Microbiology and Infection Medicine Tübingen, Tübingen, Germany
| | - Martin Fraunholz
- Biocenter, Chair of Microbiology, University of Würzburg, Würzburg, Germany
| | - Christian A Hübner
- Institute of Human Genetics, Jena University Hospital, Friedrich Schiller Universität, Jena, Germany
| | - Bettina Löffler
- Institute of Medical Microbiology, Jena University Hospital, Jena, Germany
| | - Lorena Tuchscherr
- Institute of Medical Microbiology, Jena University Hospital, Jena, Germany
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15
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Soe YM, Bedoui S, Stinear TP, Hachani A. Intracellular Staphylococcus aureus and host cell death pathways. Cell Microbiol 2021; 23:e13317. [PMID: 33550697 DOI: 10.1111/cmi.13317] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 01/22/2021] [Accepted: 01/23/2021] [Indexed: 12/13/2022]
Abstract
Staphylococcus aureus is a major opportunistic human pathogen that is globally prevalent. Although S. aureus and humans may have co-evolved to the point of commensalism, the bacterium is equipped with virulence factors causing devastating infections. The adoption of an intracellular lifestyle by S. aureus is an important facet of its pathogenesis. Occupying a privileged intracellular compartment permits evasion from the bactericidal actions of host immunity and antibiotics. However, this localization exposes S. aureus to cell-intrinsic processes comprising autophagy, metabolic challenges and clearance mechanisms orchestrated by host programmed cell death pathways (PCDs), including apoptosis, pyroptosis and necroptosis. Mounting evidence suggests that S. aureus deploys pathoadaptive mechanisms that modulate the expression of its virulence factors to prevent elimination through PCD pathways. In this review, we critically analyse the current literature on the interplay between S. aureus virulence factors with the key, intertwined nodes of PCD. We discuss how S. aureus adaptation to the human host plays an essential role in the evasion of PCD, and we consider future directions to study S. aureus-PCD interactions.
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Affiliation(s)
- Ye Mon Soe
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Sammy Bedoui
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Timothy P Stinear
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Abderrahman Hachani
- Department of Microbiology and Immunology, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
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16
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Gor V, Ohniwa RL, Morikawa K. No Change, No Life? What We Know about Phase Variation in Staphylococcus aureus. Microorganisms 2021; 9:microorganisms9020244. [PMID: 33503998 PMCID: PMC7911514 DOI: 10.3390/microorganisms9020244] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 01/22/2021] [Accepted: 01/23/2021] [Indexed: 12/13/2022] Open
Abstract
Phase variation (PV) is a well-known phenomenon of high-frequency reversible gene-expression switching. PV arises from genetic and epigenetic mechanisms and confers a range of benefits to bacteria, constituting both an innate immune strategy to infection from bacteriophages as well as an adaptation strategy within an infected host. PV has been well-characterized in numerous bacterial species; however, there is limited direct evidence of PV in the human opportunistic pathogen Staphylococcus aureus. This review provides an overview of the mechanisms that generate PV and focuses on earlier and recent findings of PV in S. aureus, with a brief look at the future of the field.
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Affiliation(s)
- Vishal Gor
- Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan
- Correspondence: (V.G.); (K.M.)
| | - Ryosuke L. Ohniwa
- Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan;
| | - Kazuya Morikawa
- Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan;
- Correspondence: (V.G.); (K.M.)
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17
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Sargison F, Alves J, Pickering A, Fitzgerald JR. Staphylococcus aureus secreted lipases do not inhibit innate immune killing mechanisms. Wellcome Open Res 2020; 5:286. [DOI: 10.12688/wellcomeopenres.16194.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/26/2020] [Indexed: 11/20/2022] Open
Abstract
Background: Staphylococcus aureus causes an array of diseases in both humans and livestock. Pathogenesis is mediated by a plethora of proteins secreted by S. aureus, many of which remain incompletely characterised. For example, S. aureus abundantly secretes two isoforms of the enzyme lipase into the extracellular milieu, where they scavenge upon polymeric triglycerides. It has previously been suggested that lipases may interfere with the function of innate immune cells, such as macrophages and neutrophils, but the impact of lipases on phagocytic killing mechanisms remains unknown. Methods: We employed the epidemic S. aureus clone USA300 strain LAC and its lipase deficient isogenic mutant, along with recombinant lipase proteins, in in vitro experimental infection assays. To determine if lipases can inhibit innate immune killing mechanisms, the bactericidal activity of whole blood, human neutrophils, and macrophages was analysed. In addition, gentamycin protection assays were carried out to examine the influence of lipases on S. aureus innate immune cell escape. Results: There were no differences in the survival of S. aureus USA300 LAC wild type and its lipase-deficient isogenic mutant after incubation with human whole blood or neutrophils. Furthermore, there was no detectable lipase-dependent effect on phagocytosis, intracellular survival, or escape from both human primary and immortalised cell line macrophages, even upon supplementation with exogenous recombinant lipases. Conclusions: S. aureus lipases do not inhibit bacterial killing mechanisms of human macrophages, neutrophils, or whole blood. These findings broaden our understanding of the interaction of S. aureus with the innate immune system.
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18
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Ellermann M, Sperandio V. Bacterial signaling as an antimicrobial target. Curr Opin Microbiol 2020; 57:78-86. [PMID: 32916624 DOI: 10.1016/j.mib.2020.08.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 07/29/2020] [Accepted: 08/03/2020] [Indexed: 12/12/2022]
Abstract
Antibiotics profoundly reduced worldwide mortality. However, the emergence of resistance to the growth inhibiting effects of these drugs occurred. New approaches to treat infectious disease that reduce the likelihood for resistance are needed. In bacterial pathogens, complex signaling networks regulate virulence. Anti-virulence therapies aim to disrupt these networks to attenuate virulence without affecting growth. Quorum-sensing, a cell-to-cell communication system, represents an attractive anti-virulence target because it often activates virulence. The challenge is to identify druggable targets that inhibit virulence, while also minimizing the likelihood of mutations promoting resistance. Moreover, given the ubiquity of quorum-sensing systems in commensals, any potential effects of anti-virulence therapies on microbiome function should also be considered. Here we highlight the efficacy and drawbacks of anti-virulence approaches.
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Affiliation(s)
- Melissa Ellermann
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, TX, USA; Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Vanessa Sperandio
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, TX, USA; Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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19
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Butrico CE, Cassat JE. Quorum Sensing and Toxin Production in Staphylococcus aureus Osteomyelitis: Pathogenesis and Paradox. Toxins (Basel) 2020; 12:toxins12080516. [PMID: 32806558 PMCID: PMC7471978 DOI: 10.3390/toxins12080516] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 08/04/2020] [Accepted: 08/10/2020] [Indexed: 01/18/2023] Open
Abstract
Staphylococcus aureus is a Gram-positive pathogen capable of infecting nearly every vertebrate organ. Among these tissues, invasive infection of bone (osteomyelitis) is particularly common and induces high morbidity. Treatment of osteomyelitis is notoriously difficult and often requires debridement of diseased bone in conjunction with prolonged antibiotic treatment to resolve infection. During osteomyelitis, S. aureus forms characteristic multicellular microcolonies in distinct niches within bone. Virulence and metabolic responses within these multicellular microcolonies are coordinated, in part, by quorum sensing via the accessory gene regulator (agr) locus, which allows staphylococcal populations to produce toxins and adapt in response to bacterial density. During osteomyelitis, the Agr system significantly contributes to dysregulation of skeletal homeostasis and disease severity but may also paradoxically inhibit persistence in the host. Moreover, the Agr system is subject to complex crosstalk with other S. aureus regulatory systems, including SaeRS and SrrAB, which can significantly impact the progression of osteomyelitis. The objective of this review is to highlight Agr regulation, its implications on toxin production, factors that affect Agr activation, and the potential paradoxical influences of Agr regulation on disease progression during osteomyelitis.
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Affiliation(s)
- Casey E. Butrico
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA;
| | - James E. Cassat
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA;
- Department of Pediatrics, Division of Pediatric Infectious Diseases, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Vanderbilt Center for Bone Biology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN 37232, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation (VI4), Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Correspondence: ; Tel.: +1-615-936-6494
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20
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Menendez-Gil P, Caballero CJ, Catalan-Moreno A, Irurzun N, Barrio-Hernandez I, Caldelari I, Toledo-Arana A. Differential evolution in 3'UTRs leads to specific gene expression in Staphylococcus. Nucleic Acids Res 2020; 48:2544-2563. [PMID: 32016395 PMCID: PMC7049690 DOI: 10.1093/nar/gkaa047] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 12/05/2019] [Accepted: 01/16/2020] [Indexed: 12/16/2022] Open
Abstract
The evolution of gene expression regulation has contributed to species differentiation. The 3′ untranslated regions (3′UTRs) of mRNAs include regulatory elements that modulate gene expression; however, our knowledge of their implications in the divergence of bacterial species is currently limited. In this study, we performed genome-wide comparative analyses of mRNAs encoding orthologous proteins from the genus Staphylococcus and found that mRNA conservation was lost mostly downstream of the coding sequence (CDS), indicating the presence of high sequence diversity in the 3′UTRs of orthologous genes. Transcriptomic mapping of different staphylococcal species confirmed that 3′UTRs were also variable in length. We constructed chimeric mRNAs carrying the 3′UTR of orthologous genes and demonstrated that 3′UTR sequence variations affect protein production. This suggested that species-specific functional 3′UTRs might be specifically selected during evolution. 3′UTR variations may occur through different processes, including gene rearrangements, local nucleotide changes, and the transposition of insertion sequences. By extending the conservation analyses to specific 3′UTRs, as well as the entire set of Escherichia coli and Bacillus subtilis mRNAs, we showed that 3′UTR variability is widespread in bacteria. In summary, our work unveils an evolutionary bias within 3′UTRs that results in species-specific non-coding sequences that may contribute to bacterial diversity.
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Affiliation(s)
- Pilar Menendez-Gil
- Instituto de Agrobiotecnología (IdAB), CSIC-UPNA-Gobierno de Navarra, 31192-Mutilva, Navarra, Spain
| | - Carlos J Caballero
- Instituto de Agrobiotecnología (IdAB), CSIC-UPNA-Gobierno de Navarra, 31192-Mutilva, Navarra, Spain
| | - Arancha Catalan-Moreno
- Instituto de Agrobiotecnología (IdAB), CSIC-UPNA-Gobierno de Navarra, 31192-Mutilva, Navarra, Spain
| | - Naiara Irurzun
- Instituto de Agrobiotecnología (IdAB), CSIC-UPNA-Gobierno de Navarra, 31192-Mutilva, Navarra, Spain
| | - Inigo Barrio-Hernandez
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Genome Campus, Hinxton, Cambridgeshire, CB10 1SD, UK
| | - Isabelle Caldelari
- Université de Strasbourg, CNRS, Architecture et Réactivité de l'ARN, UPR9002, F-67000-Strasbourg, France
| | - Alejandro Toledo-Arana
- Instituto de Agrobiotecnología (IdAB), CSIC-UPNA-Gobierno de Navarra, 31192-Mutilva, Navarra, Spain
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