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Shi C, Patel VA, Mitchell DA, Zhao H. Enterolyin S, a Polythiazole-containing Hemolytic Peptide from Enterococcus caccae. Chembiochem 2024:e202400212. [PMID: 38648232 DOI: 10.1002/cbic.202400212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Revised: 04/19/2024] [Accepted: 04/22/2024] [Indexed: 04/25/2024]
Abstract
The β-hemolytic factor streptolysin S (SLS) is an important linear azol(in)e-containing peptide (LAP) that contributes significantly to the virulence of Streptococcus pyogenes. Despite its discovery 85 years ago, SLS has evaded structural characterizing owing to its notoriously problematic physicochemical properties. Here, we report the discovery and characterization of a structurally analogous hemolytic peptide from Enterococcus caccae, termed enterolysin S (ELS). Through heterologous expression, site-directed mutagenesis, chemoselective modification, and high-resolution mass spectrometry, we found that ELS contains an intriguing contiguous octathiazole moiety. The discovery of ELS expands our knowledge of hemolytic LAPs by adding a new member to this virulence-promoting family of modified peptides.
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Affiliation(s)
- Chengyou Shi
- Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana Champaign, Urbana, IL, 61801, USA
- Department of Chemical and Biomolecular Engineering, Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana Champaign, Urbana, IL, 61801, USA
| | - Varshal A Patel
- Department of Biochemistry, University of Illinois, Urbana Champaign, Urbana, IL, 61801, USA
| | - Douglas A Mitchell
- Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana Champaign, Urbana, IL, 61801, USA
- Department of Chemistry, University of Illinois, Urbana Champaign, Urbana, IL, 61801, USA
| | - Huimin Zhao
- Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana Champaign, Urbana, IL, 61801, USA
- Department of Chemical and Biomolecular Engineering, Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana Champaign, Urbana, IL, 61801, USA
- Department of Biochemistry, University of Illinois, Urbana Champaign, Urbana, IL, 61801, USA
- Department of Chemistry, University of Illinois, Urbana Champaign, Urbana, IL, 61801, USA
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2
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Su MSW, Cheng YL, Lin YS, Wu JJ. Interplay between group A Streptococcus and host innate immune responses. Microbiol Mol Biol Rev 2024; 88:e0005222. [PMID: 38451081 PMCID: PMC10966951 DOI: 10.1128/mmbr.00052-22] [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: 03/08/2024] Open
Abstract
SUMMARYGroup A Streptococcus (GAS), also known as Streptococcus pyogenes, is a clinically well-adapted human pathogen that harbors rich virulence determinants contributing to a broad spectrum of diseases. GAS is capable of invading epithelial, endothelial, and professional phagocytic cells while evading host innate immune responses, including phagocytosis, selective autophagy, light chain 3-associated phagocytosis, and inflammation. However, without a more complete understanding of the different ways invasive GAS infections develop, it is difficult to appreciate how GAS survives and multiplies in host cells that have interactive immune networks. This review article attempts to provide an overview of the behaviors and mechanisms that allow pathogenic GAS to invade cells, along with the strategies that host cells practice to constrain GAS infection. We highlight the counteractions taken by GAS to apply virulence factors such as streptolysin O, nicotinamide-adenine dinucleotidase, and streptococcal pyrogenic exotoxin B as a hindrance to host innate immune responses.
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Affiliation(s)
- Marcia Shu-Wei Su
- Department of Medical Laboratory Science and Biotechnology, College of Medical and Health Sciences, Asia University, Taichung, Taiwan
- Department of Biotechnology and Laboratory Science in Medicine, College of Biomedical Science and Engineering, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Yi-Lin Cheng
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Center of Infectious Disease and Signaling Research, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Yee-Shin Lin
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Center of Infectious Disease and Signaling Research, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Jiunn-Jong Wu
- Department of Medical Laboratory Science and Biotechnology, College of Medical and Health Sciences, Asia University, Taichung, Taiwan
- Department of Biotechnology and Laboratory Science in Medicine, College of Biomedical Science and Engineering, National Yang Ming Chiao Tung University, Taipei, Taiwan
- Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, Taiwan
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3
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Shannon BA, Hurst JR, Flannagan RS, Craig HC, Rishi A, Kasper KJ, Tuffs SW, Heinrichs DE, McCormick JK. Streptolysin S is required for Streptococcus pyogenes nasopharyngeal and skin infection in HLA-transgenic mice. PLoS Pathog 2024; 20:e1012072. [PMID: 38452154 PMCID: PMC10950238 DOI: 10.1371/journal.ppat.1012072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 03/19/2024] [Accepted: 02/25/2024] [Indexed: 03/09/2024] Open
Abstract
Streptococcus pyogenes is a human-specific pathogen that commonly colonizes the upper respiratory tract and skin, causing a wide variety of diseases ranging from pharyngitis to necrotizing fasciitis and toxic shock syndrome. S. pyogenes has a repertoire of secreted virulence factors that promote infection and evasion of the host immune system including the cytolysins streptolysin O (SLO) and streptolysin S (SLS). S. pyogenes does not naturally infect the upper respiratory tract of mice although mice transgenic for MHC class II human leukocyte antigens (HLA) become highly susceptible. Here we used HLA-transgenic mice to assess the role of both SLO and SLS during both nasopharyngeal and skin infection. Using S. pyogenes MGAS8232 as a model strain, we found that an SLS-deficient strain exhibited a 100-fold reduction in bacterial recovery from the nasopharynx and a 10-fold reduction in bacterial burden in the skin, whereas an SLO-deficient strain did not exhibit any infection defects in these models. Furthermore, depletion of neutrophils significantly restored the bacterial burden of the SLS-deficient bacteria in skin, but not in the nasopharynx. In mice nasally infected with the wildtype S. pyogenes, there was a marked change in localization of the tight junction protein ZO-1 at the site of infection, demonstrating damage to the nasal epithelia that was absent in mice infected with the SLS-deficient strain. Overall, we conclude that SLS is required for the establishment of nasopharyngeal infection and skin infection in HLA-transgenic mice by S. pyogenes MGAS8232 and provide evidence that SLS contributes to nasopharyngeal infection through the localized destruction of nasal epithelia.
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Affiliation(s)
- Blake A. Shannon
- Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada
| | - Jacklyn R. Hurst
- Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada
| | - Ronald S. Flannagan
- Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada
| | - Heather C. Craig
- Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada
| | - Aanchal Rishi
- Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada
| | - Katherine J. Kasper
- Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada
| | - Stephen W. Tuffs
- Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada
| | - David E. Heinrichs
- Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada
| | - John K. McCormick
- Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada
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4
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Jia K, Wang J, Zhai R, Du Y, Kira J, Wu C, Qian PY, Zhang W. Abi Family Protein, DidK, Is Involved in the Maturation of Anticancer Depsipeptide, Didemnin B. ACS Chem Biol 2023; 18:2300-2308. [PMID: 37773034 DOI: 10.1021/acschembio.3c00393] [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: 09/30/2023]
Abstract
Didemnin B is a marine-derived depsipeptide with potent antiviral and anticancer activities. A prodrug activation mechanism was previously proposed for the biosynthesis of didemnin B by the nonribosomal peptide synthetase/polyketide synthase (NRPS/PKS) assembly line, but the enzyme involved in the maturation process remained unknown. Herein, we demonstrated that DidA, a dimodular NRPS predicted with unrelated activity to didemnin B structure assembly, was indispensable to produce didemnin B, confirming the prodrug mechanism in didemnin B biosynthesis. We further identified an Abi family transmembrane protease, DidK, that functioned as an esterase in the maturation step of didemnin B by in vivo gene knockout and heterologous expression. DidK is structurally distinct from other known hydrolytic enzymes involved in the maturation of bacterial nonribosomal peptides and is the first Abi family protein known to participate in NRPS/PKS-derived natural product production. Further bioinformatic analysis revealed more than 20 DidK homologues encoded in bacterial NRPS/PKS BGCs, suggesting that the involvement of Abi family proteins in natural product biosynthesis might not be rare. These results not only clarify the priming and maturation steps of didemnin B biosynthesis but also expand the function scope of Abi family proteins.
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Affiliation(s)
- Kaimin Jia
- Department of Chemical and Biomolecular Engineering, University of California Berkeley, Berkeley, California 94720, United States
- California Institute for Quantitative Biosciences, University of California Berkeley, Berkeley, California 94720, United States
| | - Jiayu Wang
- Department of Chemistry, University of California Berkeley, Berkeley, California 94720, United States
| | - Rui Zhai
- Department of Chemical and Biomolecular Engineering, University of California Berkeley, Berkeley, California 94720, United States
- California Institute for Quantitative Biosciences, University of California Berkeley, Berkeley, California 94720, United States
| | - Yongle Du
- Department of Chemical and Biomolecular Engineering, University of California Berkeley, Berkeley, California 94720, United States
- California Institute for Quantitative Biosciences, University of California Berkeley, Berkeley, California 94720, United States
| | - Jenna Kira
- Department of Chemical and Biomolecular Engineering, University of California Berkeley, Berkeley, California 94720, United States
| | - Chuanhai Wu
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
- Department of Ocean Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China
| | - Pei-Yuan Qian
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
- Department of Ocean Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China
| | - Wenjun Zhang
- Department of Chemical and Biomolecular Engineering, University of California Berkeley, Berkeley, California 94720, United States
- California Institute for Quantitative Biosciences, University of California Berkeley, Berkeley, California 94720, United States
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5
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Wahlenmayer ER, Hammers DE. Streptococcal peptides and their roles in host-microbe interactions. Front Cell Infect Microbiol 2023; 13:1282622. [PMID: 37915845 PMCID: PMC10617681 DOI: 10.3389/fcimb.2023.1282622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 10/02/2023] [Indexed: 11/03/2023] Open
Abstract
The genus Streptococcus encompasses many bacterial species that are associated with hosts, ranging from asymptomatic colonizers and commensals to pathogens with a significant global health burden. Streptococci produce numerous factors that enable them to occupy their host-associated niches, many of which alter their host environment to the benefit of the bacteria. The ability to manipulate host immune systems to either evade detection and clearance or induce a hyperinflammatory state influences whether bacteria are able to survive and persist in a given environment, while also influencing the propensity of the bacteria to cause disease. Several bacterial factors that contribute to this inter-species interaction have been identified. Recently, small peptides have become increasingly appreciated as factors that contribute to Streptococcal relationships with their hosts. Peptides are utilized by streptococci to modulate their host environment in several ways, including by directly interacting with host factors to disrupt immune system function and signaling to other bacteria to control the expression of genes that contribute to immune modulation. In this review, we discuss the many contributions of Streptococcal peptides in terms of their ability to contribute to pathogenesis and disruption of host immunity. This discussion will highlight the importance of continuing to elucidate the functions of these Streptococcal peptides and pursuing the identification of new peptides that contribute to modulation of host environments. Developing a greater understanding of how bacteria interact with their hosts has the potential to enable the development of techniques to inhibit these peptides as therapeutic approaches against Streptococcal infections.
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Affiliation(s)
| | - Daniel E. Hammers
- Biology Department, Houghton University, Houghton, NY, United States
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6
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Fazel P, Sedighian H, Behzadi E, Kachuei R, Imani Fooladi AA. Interaction Between SARS-CoV-2 and Pathogenic Bacteria. Curr Microbiol 2023; 80:223. [PMID: 37222840 DOI: 10.1007/s00284-023-03315-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 04/28/2023] [Indexed: 05/25/2023]
Abstract
The novel human coronavirus, Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), which results in the coronavirus disease 2019 (COVID-19), has caused a serious threat to global public health. Therefore, many studies are performed on the causes and prevalence of this disease and the possible co-occurrence of the infection with other viral and bacterial pathogens is investigated. Respiratory infections predispose patients to co-infections and these lead to increased disease severity and mortality. Numerous types of antibiotics have been employed for the prevention and treatment of bacterial co-infection and secondary bacterial infections in patients with a SARS-CoV-2 infection. Although antibiotics do not directly affect SARS-CoV-2, viral respiratory infections often result in bacterial pneumonia. It is possible that some patients die from bacterial co-infection rather than virus itself. Therefore, bacterial co-infection and secondary bacterial infection are considered critical risk factors for the severity and mortality rates of COVID-19. In this review, we will summarize the bacterial co-infection and secondary bacterial infection in some featured respiratory viral infections, especially COVID-19.
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Affiliation(s)
- Parvindokht Fazel
- Department of Microbiology, Fars Science and Research Branch, Islamic Azad University, Eqlid, Fars, Iran
- Department of Microbiology, Shiraz Branch, Islamic Azad University, Shiraz, Iran
| | - Hamid Sedighian
- Applied Microbiology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Vanak Sq, Mollasadra St, P.O. Box 19395-5487, Tehran, Iran
| | - Elham Behzadi
- Academy of Medical Sciences of the I.R. of Iran, Tehran, Iran
| | - Reza Kachuei
- Molecular Biology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Abbas Ali Imani Fooladi
- Applied Microbiology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Vanak Sq, Mollasadra St, P.O. Box 19395-5487, Tehran, Iran.
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7
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Lactiplantibacillus plantarum KAU007 Extract Modulates Critical Virulence Attributes and Biofilm Formation in Sinusitis Causing Streptococcus pyogenes. Pharmaceutics 2022; 14:pharmaceutics14122702. [PMID: 36559194 PMCID: PMC9780990 DOI: 10.3390/pharmaceutics14122702] [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: 10/19/2022] [Revised: 11/25/2022] [Accepted: 11/29/2022] [Indexed: 12/09/2022] Open
Abstract
Streptococcus pyogenes is one of the most common bacteria causing sinusitis in children and adult patients. Probiotics are known to cause antagonistic effects on S. pyogenes growth and biofilm formation. In the present study, we demonstrated the anti-biofilm and anti-virulence properties of Lactiplantibacillus plantarum KAU007 against S. pyogenes ATCC 8668. The antibacterial potential of L. plantarum KAU007 metabolite extract (LME) purified from the cell-free supernatant of L. plantarum KAU007 was evaluated in terms of minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC). LME was further analyzed for its anti-biofilm potential using crystal violet assay and microscopic examination. Furthermore, the effect of LME was tested on the important virulence attributes of S. pyogenes, such as secreted protease production, hemolysis, extracellular polymeric substance production, and cell surface hydrophobicity. Additionally, the impact of LME on the expression of genes associated with biofilm formation and virulence attributes was analyzed using qPCR. The results revealed that LME significantly inhibited the growth and survival of S. pyogenes at a low concentration (MIC, 9.76 µg/mL; MBC, 39.06 µg/mL). Furthermore, LME inhibited biofilm formation and mitigated the production of extracellular polymeric substance at a concentration of 4.88 μg/mL in S. pyogenes. The results obtained from qPCR and biochemical assays advocated that LME suppresses the expression of various critical virulence-associated genes, which correspondingly affect various pathogenicity markers and were responsible for the impairment of virulence and biofilm formation in S. pyogenes. The non-hemolytic nature of LME and its anti-biofilm and anti-virulence properties against S. pyogenes invoke further investigation to study the role of LME as an antibacterial agent to combat streptococcal infections.
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8
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Hammers DE, Donahue DL, Tucker Z, Ashfeld BL, Ploplis VA, Castellino FJ, Lee SW. Streptolysin S targets the sodium-bicarbonate cotransporter NBCn1 to induce inflammation and cytotoxicity in human keratinocytes during Group A Streptococcal infection. Front Cell Infect Microbiol 2022; 12:1002230. [PMID: 36389147 PMCID: PMC9663810 DOI: 10.3389/fcimb.2022.1002230] [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] [Received: 07/24/2022] [Accepted: 09/29/2022] [Indexed: 11/30/2022] Open
Abstract
Group A <i>Streptococcus</i> (GAS, <i>Streptococcus pyogenes</i>) is a Gram-positive human pathogen that employs several secreted and surface-bound virulence factors to manipulate its environment, allowing it to cause a variety of disease outcomes. One such virulence factor is Streptolysin S (SLS), a ribosomally-produced peptide toxin that undergoes extensive post-translational modifications. The activity of SLS has been studied for over 100 years owing to its rapid and potent ability to lyse red blood cells, and the toxin has been shown to play a major role in GAS virulence <i>in vivo</i>. We have previously demonstrated that SLS induces hemolysis by targeting the chloride-bicarbonate exchanger Band 3 in erythrocytes, indicating that SLS is capable of targeting host proteins to promote cell lysis. However, the possibility that SLS has additional protein targets in other cell types, such as keratinocytes, has not been explored. Here, we use bioinformatics analysis and chemical inhibition studies to demonstrate that SLS targets the electroneutral sodium-bicarbonate cotransporter NBCn1 in keratinocytes during GAS infection. SLS induces NF-κB activation and host cytotoxicity in human keratinocytes, and these processes can be mitigated by treating keratinocytes with the sodium-bicarbonate cotransport inhibitor S0859. Furthermore, treating keratinocytes with SLS disrupts the ability of host cells to regulate their intracellular pH, and this can be monitored in real time using the pH-sensitive dye pHrodo Red AM in live imaging studies. These results demonstrate that SLS is a multifunctional bacterial toxin that GAS uses in numerous context-dependent ways to promote host cell cytotoxicity and increase disease severity. Studies to elucidate additional host targets of SLS have the potential to impact the development of therapeutics for severe GAS infections.
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Affiliation(s)
- Daniel E. Hammers
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, United States,Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN, United States
| | - Deborah L. Donahue
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, United States,William Myron (W. M.) Keck Center for Transgene Research, University of Notre Dame, Notre Dame, IN, United States
| | - Zachary D. Tucker
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, United States
| | - Brandon L. Ashfeld
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, United States
| | - Victoria A. Ploplis
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, United States,William Myron (W. M.) Keck Center for Transgene Research, University of Notre Dame, Notre Dame, IN, United States
| | - Francis J. Castellino
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, United States,William Myron (W. M.) Keck Center for Transgene Research, University of Notre Dame, Notre Dame, IN, United States
| | - Shaun W. Lee
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, United States,Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN, United States,William Myron (W. M.) Keck Center for Transgene Research, University of Notre Dame, Notre Dame, IN, United States,*Correspondence: Shaun W. Lee,
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9
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Liu S, Deng S, Liu H, Tang L, Wang M, Xin B, Li F. Four Novel Leaderless Bacteriocins, Bacin A1, A2, A3, and A4 Exhibit Potent Antimicrobial and Antibiofilm Activities against Methicillin-Resistant Staphylococcus aureus. Microbiol Spectr 2022; 10:e0094522. [PMID: 36000904 PMCID: PMC9602277 DOI: 10.1128/spectrum.00945-22] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 07/26/2022] [Indexed: 12/30/2022] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is a major bacterial pathogen that causes hospital- and community-acquired infections. Owing to its multidrug resistance, it is imperative to develop new antimicrobial agents to treat MRSA infections. In this study, using genome mining analysis and a culture-based screening method to detect bacteriocin activity, we screened a strain, Bacillus sp. TL12, which harbored a putative leaderless bacteriocin gene cluster (bac gene cluster) and exhibited potent anti-MRSA activity. The antimicrobial agents, products of the bac gene cluster, were purified and identified as four novel leaderless bacteriocins: bacin A1, A2, A3, and A4. Bacin A2 was evaluated as a representative antimicrobial agent and showed remarkable antimicrobial activity against S. aureus, MRSA, and the foodborne pathogens Listeria monocytogenes and Bacillus cereus. Mechanistic experiments revealed that bacin A2 damaged cell membranes and exhibited bactericidal activity against MRSA. Bacin A2 effectively inhibited the formation of S. aureus and MRSA biofilms (>0.5× MIC) and killed the cells in their established biofilms (>4× MIC). The hemolytic and NIH/3T3 cytotoxicity assay results for bacin A2 confirmed its biosafety. Thus, bacins have potential as alternative antimicrobial agents for treating MRSA infections. IMPORTANCE Methicillin-resistant Staphylococcus aureus (MRSA) is a major human pathogen that is difficult to treat because of its resistance to several widely used antibiotics. The present study aimed to identify novel anti-MRSA bacteriocins in a prominent producer of bacteriocins, Bacillus cereus group. Four novel leaderless bacteriocins, bacin A1, A2, A3, and A4, which show potent bactericidal effect against S. aureus and MRSA, were identified in Bacillus sp. TL12. Moreover, bacins inhibited biofilm formation and killed cells in the established biofilms of S. aureus and MRSA. These findings suggest that bacins are promising alternatives to treat MRSA infections.
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Affiliation(s)
- Shu Liu
- Anhui Province Key Laboratory of Pollutant Sensitive Materials and Environmental Remediation, College of Life Sciences, Huaibei Normal University, Huaibei, Anhui Province, China
| | - Shulin Deng
- Anhui Province Key Laboratory of Pollutant Sensitive Materials and Environmental Remediation, College of Life Sciences, Huaibei Normal University, Huaibei, Anhui Province, China
| | - Hualin Liu
- School of Marine Sciences, Sun Yat-sen University, Zhuhai, Guangdong Province, China
| | - Liang Tang
- Anhui Province Key Laboratory of Pollutant Sensitive Materials and Environmental Remediation, College of Life Sciences, Huaibei Normal University, Huaibei, Anhui Province, China
| | - Mengqi Wang
- Anhui Province Key Laboratory of Pollutant Sensitive Materials and Environmental Remediation, College of Life Sciences, Huaibei Normal University, Huaibei, Anhui Province, China
| | - Bingyue Xin
- Anhui Province Key Laboratory of Pollutant Sensitive Materials and Environmental Remediation, College of Life Sciences, Huaibei Normal University, Huaibei, Anhui Province, China
| | - Feng Li
- Anhui Province Key Laboratory of Pollutant Sensitive Materials and Environmental Remediation, College of Life Sciences, Huaibei Normal University, Huaibei, Anhui Province, China
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10
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Ongpipattanakul C, Desormeaux EK, DiCaprio A, van der Donk WA, Mitchell DA, Nair SK. Mechanism of Action of Ribosomally Synthesized and Post-Translationally Modified Peptides. Chem Rev 2022; 122:14722-14814. [PMID: 36049139 PMCID: PMC9897510 DOI: 10.1021/acs.chemrev.2c00210] [Citation(s) in RCA: 46] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Ribosomally synthesized and post-translationally modified peptides (RiPPs) are a natural product class that has undergone significant expansion due to the rapid growth in genome sequencing data and recognition that they are made by biosynthetic pathways that share many characteristic features. Their mode of actions cover a wide range of biological processes and include binding to membranes, receptors, enzymes, lipids, RNA, and metals as well as use as cofactors and signaling molecules. This review covers the currently known modes of action (MOA) of RiPPs. In turn, the mechanisms by which these molecules interact with their natural targets provide a rich set of molecular paradigms that can be used for the design or evolution of new or improved activities given the relative ease of engineering RiPPs. In this review, coverage is limited to RiPPs originating from bacteria.
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Affiliation(s)
- Chayanid Ongpipattanakul
- Department of Biochemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA
| | - Emily K. Desormeaux
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA
| | - Adam DiCaprio
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA
| | - Wilfred A. van der Donk
- Department of Biochemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA.,Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA.,Department of Howard Hughes Medical Institute, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA.,Departments of Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1206 West Gregory Drive, Urbana, Illinois 61801, USA.,Corresponding authors Wilfred A. van der Donk, , 217-244-5360, Douglas A. Mitchell, , 217-333-1345, Satish K. Nair, , 217-333-0641
| | - Douglas A. Mitchell
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA.,Department of Microbiology, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA.,Departments of Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1206 West Gregory Drive, Urbana, Illinois 61801, USA.,Corresponding authors Wilfred A. van der Donk, , 217-244-5360, Douglas A. Mitchell, , 217-333-1345, Satish K. Nair, , 217-333-0641
| | - Satish K. Nair
- Department of Biochemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA.,Departments of Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1206 West Gregory Drive, Urbana, Illinois 61801, USA.,Corresponding authors Wilfred A. van der Donk, , 217-244-5360, Douglas A. Mitchell, , 217-333-1345, Satish K. Nair, , 217-333-0641
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11
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Alves-Barroco C, Brito PH, Santos-Sanches I, Fernandes AR. Phylogenetic analysis and accessory genome diversity reveal insight into the evolutionary history of Streptococcus dysgalactiae. Front Microbiol 2022; 13:952110. [PMID: 35928143 PMCID: PMC9343751 DOI: 10.3389/fmicb.2022.952110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 06/27/2022] [Indexed: 11/13/2022] Open
Abstract
Streptococcus dysgalactiae (SD) is capable of infecting both humans and animals and causing a wide range of invasive and non-invasive infections. With two subspecies, the taxonomic status of subspecies of SD remains controversial. Subspecies equisimilis (SDSE) is an important human pathogen, while subspecies dysgalactiae (SDSD) has been considered a strictly animal pathogen; however, occasional human infections by this subspecies have been reported in the last few years. Moreover, the differences between the adaptation of SDSD within humans and other animals are still unknown. In this work, we provide a phylogenomic analysis based on the single-copy core genome of 106 isolates from both the subspecies and different infected hosts (animal and human hosts). The accessory genome of this species was also analyzed for screening of genes that could be specifically involved with adaptation to different hosts. Additionally, we searched putatively adaptive traits among prophage regions to infer the importance of transduction in the adaptation of SD to different hosts. Core genome phylogenetic relationships segregate all human SDSE in a single cluster separated from animal SD isolates. The subgroup of bovine SDSD evolved from this later clade and harbors a specialized accessory genome characterized by the presence of specific virulence determinants (e.g., cspZ) and carbohydrate metabolic functions (e.g., fructose operon). Together, our results indicate a host-specific SD and the existence of an SDSD group that causes human–animal cluster infections may be due to opportunistic infections, and that the exact incidence of SDSD human infections may be underestimated due to failures in identification based on the hemolytic patterns. However, more detailed research into the isolation of human SD is needed to assess whether it is a carrier phenomenon or whether the species can be permanently integrated into the human microbiome, making it ready to cause opportunistic infections.
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Affiliation(s)
- Cinthia Alves-Barroco
- Applied Molecular Biosciences Unit (UCIBIO), Departamento de Ciências da Vida, NOVA School of Science and Technology, Costa da Caparica, Portugal
- i4HB, Associate Laboratory – Institute for Health and Bioeconomy, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Costa da Caparica, Portugal
- *Correspondence: Cinthia Alves-Barroco,
| | - Patrícia H. Brito
- Applied Molecular Biosciences Unit (UCIBIO), Departamento de Ciências da Vida, NOVA School of Science and Technology, Costa da Caparica, Portugal
- i4HB, Associate Laboratory – Institute for Health and Bioeconomy, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Costa da Caparica, Portugal
- NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Lisbon, Portugal
- Patrícia H. Brito,
| | - Ilda Santos-Sanches
- Applied Molecular Biosciences Unit (UCIBIO), Departamento de Ciências da Vida, NOVA School of Science and Technology, Costa da Caparica, Portugal
| | - Alexandra R. Fernandes
- Applied Molecular Biosciences Unit (UCIBIO), Departamento de Ciências da Vida, NOVA School of Science and Technology, Costa da Caparica, Portugal
- i4HB, Associate Laboratory – Institute for Health and Bioeconomy, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Costa da Caparica, Portugal
- Alexandra R. Fernandes,
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12
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Alves-Barroco C, Botelho AMN, Américo MA, Fracalanzza SEL, de Matos APA, Guimaraes MA, Ferreira-Carvalho BT, Figueiredo AMS, Fernandes AR. Assessing in vivo and in vitro biofilm development by Streptococcus dysgalactiae subsp. dysgalactiae using a murine model of catheter-associated biofilm and human keratinocyte cell. Front Cell Infect Microbiol 2022; 12:874694. [PMID: 35928206 PMCID: PMC9343579 DOI: 10.3389/fcimb.2022.874694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Accepted: 06/29/2022] [Indexed: 11/13/2022] Open
Abstract
Streptococcus dysgalactiae subsp. dysgalactiae (SDSD) is an important agent of bovine mastitis. This infection causes an inflammatory reaction in udder tissue, being the most important disease-causing significant impact on the dairy industry. Therefore, it leads to an increase in dairy farming to meet commercial demands. As a result, there is a major impact on both the dairy industry and the environment including global warming. Recurrent mastitis is often attributed to the development of bacterial biofilms, which promote survival of sessile cells in hostile environments, and resistance to the immune system defense and antimicrobial therapy. Recently, we described the in vitro biofilm development on abiotic surfaces by bovine SDSD. In that work we integrated microbiology, imaging, and computational methods to evaluate the biofilm production capability of SDSD isolates on abiotic surfaces. Additionally, we reported that bovine SDSD can adhere and internalize human cells, including human epidermal keratinocyte (HEK) cells. We showed that the adherence and internalization rates of bovine SDSD isolates in HEK cells are higher than those of a SDSD DB49998-05 isolated from humans. In vivo, bovine SDSD can cause invasive infections leading to zebrafish morbidity and mortality. In the present work, we investigated for the first time the capability of bovine SDSD to develop biofilm in vivo using a murine animal model and ex-vivo on human HEK cells. Bovine SDSD isolates were selected based on their ability to form weak, moderate, or strong biofilms on glass surfaces. Our results showed that SDSD isolates displayed an increased ability to form biofilms on the surface of catheters implanted in mice when compared to in vitro biofilm formation on abiotic surface. A greater ability to form biofilm in vitro after animal passage was observed for the VSD45 isolate, but not for the other isolates tested. Besides that, in vitro scanning electron microscopy demonstrated that SDSD biofilm development was visible after 4 hours of SDSD adhesion to HEK cells. Cell viability tests showed an important reduction in the number of HEK cells after the formation of SDSD biofilms. In this study, the expression of genes encoding BrpA-like (biofilm regulatory protein), FbpA (fibronectin-binding protein A), HtrA (serine protease), and SagA (streptolysin S precursor) was higher for biofilm grown in vivo than in vitro, suggesting a potential role for these virulence determinants in the biofilm-development, host colonization, and SDSD infections. Taken together, these results demonstrate that SDSD can develop biofilms in vivo and on the surface of HEK cells causing important cellular damages. As SDSD infections are considered zoonotic diseases, our data contribute to a better understanding of the role of biofilm accumulation during SDSD colonization and pathogenesis not only in bovine mastitis, but they also shed some lights on the mechanisms of prosthesis-associated infection and cellulitis caused by SDSD in humans, as well.
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Affiliation(s)
- Cinthia Alves-Barroco
- UCIBIO - Applied Molecular Biosciences Unit, Dept. Ciências da Vida, NOVA School of Science and Technology, Caparica, Portugal
- i4HB, Associate Laboratory - Institute for Health and Bioeconomy, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Caparica, Portugal
| | - Ana Maria Nunes Botelho
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marco Antonio Américo
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - António P. Alves de Matos
- Centro de Investigação Interdisciplinar Egas Moniz (CiiEM), Egas Moniz - Cooperativa de Ensino Superior CRL, Quinta da Granja, Portugal
| | - Márcia Aparecida Guimaraes
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Agnes Marie Sá Figueiredo
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- *Correspondence: Alexandra R. Fernandes, ; Agnes Marie Sá Figueiredo,
| | - Alexandra R. Fernandes
- UCIBIO - Applied Molecular Biosciences Unit, Dept. Ciências da Vida, NOVA School of Science and Technology, Caparica, Portugal
- i4HB, Associate Laboratory - Institute for Health and Bioeconomy, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Caparica, Portugal
- *Correspondence: Alexandra R. Fernandes, ; Agnes Marie Sá Figueiredo,
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Kant S, Pancholi V. Novel Tyrosine Kinase-Mediated Phosphorylation With Dual Specificity Plays a Key Role in the Modulation of Streptococcus pyogenes Physiology and Virulence. Front Microbiol 2021; 12:689246. [PMID: 34950110 PMCID: PMC8689070 DOI: 10.3389/fmicb.2021.689246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 10/25/2021] [Indexed: 11/15/2022] Open
Abstract
Streptococcus pyogenes (Group A Streptococcus, GAS) genomes do not contain a gene encoding a typical bacterial-type tyrosine kinase (BY-kinase) but contain an orphan gene-encoding protein Tyr-phosphatase (SP-PTP). Hence, the importance of Tyr-phosphorylation is underappreciated and not recognized for its role in GAS pathophysiology and pathogenesis. The fact that SP-PTP dephosphorylates Abl-tyrosine kinase-phosphorylated myelin basic protein (MBP), and SP-STK (S. pyogenes Ser/Thr kinase) also autophosphorylates its Tyr101-residue prompted us to identify a putative tyrosine kinase and Tyr-phosphorylation in GAS. Upon a genome-wide search of kinases possessing a classical Walker motif, we identified a non-canonical tyrosine kinase M5005_Spy_1476, a ∼17 kDa protein (153 aa) (SP-TyK). The purified recombinant SP-TyK autophosphorylated in the presence of ATP. In vitro and in vivo phosphoproteomic analyses revealed two key phosphorylated tyrosine residues located within the catalytic domain of SP-TyK. An isogenic mutant lacking SP-TyK derived from the M1T1 strain showed a retarded growth pattern. It displayed defective cell division and long chains with multiple parallel septa, often resulting in aggregates. Transcriptomic analysis of the mutant revealed 287 differentially expressed genes responsible for GAS pathophysiology and pathogenesis. SP-TyK also phosphorylated GAS CovR, WalR, SP-STP, and SDH/GAPDH proteins with dual specificity targeting their Tyr/Ser/Thr residues as revealed by biochemical and mass-spectrometric-based phosphoproteomic analyses. SP-TyK-phosphorylated CovR bound to PcovR efficiently. The mutant displayed sustained release of IL-6 compared to TNF-α during co-culturing with A549 lung cell lines, attenuation in mice sepsis model, and significantly reduced ability to adhere to and invade A549 lung cells and form biofilms on abiotic surfaces. SP-TyK, thus, plays a critical role in fine-tuning the regulation of key cellular functions essential for GAS pathophysiology and pathogenesis through post-translational modifications and hence, may serve as a promising target for future therapeutic developments.
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The lanthipeptide biosynthetic clusters of the domain Archaea. Microbiol Res 2021; 253:126884. [PMID: 34628131 DOI: 10.1016/j.micres.2021.126884] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 08/17/2021] [Accepted: 09/27/2021] [Indexed: 11/21/2022]
Abstract
Research on Archaea's secondary metabolites is still lagging behind that of Bacteria and Eukarya. Our goal was to contribute to this knowledge gap by analyzing the lanthipeptide's clusters in Archaea. As previously proposed, Archaea encodes only class II synthetases (LanMs), which we found to be confined to the class Halobacteria (also known as haloarchaea). In total, we analyzed the phylogeny and the domains of 42 LanMs. Four types were identified, and the majority of them belong to the CCG group due to their cyclization domain, which includes LanMs of Cyanobacteria. Putative cognate peptides were predicted for most of LanMs and are a very diverse group of molecules that share a Kx(Y/F)(D/E)xx(F/Y) motif in their leader peptides. According to their homology, some of them were categorized into subfamilies, including Halolancins, Haladacins, Haloferaxcins and Halobiforcins. Many LanM genes were associated with mobile genetic elements, and their vicinities mainly encode ABC and MFS transporters, tailoring enzymes and uncharacterized proteins. Our results suggest that the biosynthesis of lanthipeptides in haloarchaea can entail distinct enzymology that must lead to the production of peptides with novel structures and unpredicted biological and ecological roles. Finally, an Haloferax mediterranei knockout, lacking its three lanM genes, was generated, and it was concluded that its antimicrobial activity is not primarily related to the production of lanthipeptides.
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15
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Listeriolysin S: A bacteriocin from Listeria monocytogenes that induces membrane permeabilization in a contact-dependent manner. Proc Natl Acad Sci U S A 2021; 118:2108155118. [PMID: 34599102 PMCID: PMC8501752 DOI: 10.1073/pnas.2108155118] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/27/2021] [Indexed: 11/18/2022] Open
Abstract
Listeria monocytogenes (Lm) is a bacterial pathogen that causes listeriosis, a foodborne disease characterized by gastroenteritis, meningitis, bacteremia, and abortions in pregnant women. The most severe human listeriosis outbreaks are associated with a subset of Lm hypervirulent clones that encode the bacteriocin Listeriolysin S (LLS), which modifies the gut microbiota and allows efficient Lm gut colonization and invasion of deeper organs. Our present work identifies the killing mechanism displayed by LLS to outcompete gut commensal bacteria, demonstrating that it induces membrane permeabilization and membrane depolarization of target bacteria. Moreover, we show that LLS is a thiazole/oxazole–modified microcin that displays a contact-dependent inhibition mechanism. Listeriolysin S (LLS) is a thiazole/oxazole–modified microcin (TOMM) produced by hypervirulent clones of Listeria monocytogenes. LLS targets specific gram-positive bacteria and modulates the host intestinal microbiota composition. To characterize the mechanism of LLS transfer to target bacteria and its bactericidal function, we first investigated its subcellular distribution in LLS-producer bacteria. Using subcellular fractionation assays, transmission electron microscopy, and single-molecule superresolution microscopy, we identified that LLS remains associated with the bacterial cell membrane and cytoplasm and is not secreted to the bacterial extracellular space. Only living LLS-producer bacteria (and not purified LLS-positive bacterial membranes) display bactericidal activity. Applying transwell coculture systems and microfluidic-coupled microscopy, we determined that LLS requires direct contact between LLS-producer and -target bacteria in order to display bactericidal activity, and thus behaves as a contact-dependent bacteriocin. Contact-dependent exposure to LLS leads to permeabilization/depolarization of the target bacterial cell membrane and adenosine triphosphate (ATP) release. Additionally, we show that lipoteichoic acids (LTAs) can interact with LLS and that LTA decorations influence bacterial susceptibility to LLS. Overall, our results suggest that LLS is a TOMM that displays a contact-dependent inhibition mechanism.
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16
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Richter J, Monteleone MM, Cork AJ, Barnett TC, Nizet V, Brouwer S, Schroder K, Walker MJ. Streptolysins are the primary inflammasome activators in macrophages during Streptococcus pyogenes infection. Immunol Cell Biol 2021; 99:1040-1052. [PMID: 34462965 DOI: 10.1111/imcb.12499] [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] [Received: 06/22/2021] [Revised: 08/09/2021] [Accepted: 08/28/2021] [Indexed: 12/30/2022]
Abstract
Group A Streptococcus (GAS) is a Gram-positive bacterial pathogen that causes an array of infectious diseases in humans. Accumulating clinical evidence suggests that proinflammatory interleukin (IL)-1β signaling plays an important role in GAS disease progression. The host regulates the production and secretion of IL-1β via the cytosolic inflammasome pathway. Activation of the NLR family pyrin domain-containing 3 (NLRP3) inflammasome complex requires two signals: a priming signal that stimulates increased transcription of genes encoding the components of the inflammasome pathway, and an activating signal that induces assembly of the inflammasome complex. Here we show that GAS-derived lipoteichoic acid can provide a priming signal for NLRP3 inflammasome activation. As only few GAS-derived proteins have been associated with inflammasome-dependent IL-1β signaling, we investigated novel candidates that might play a role in activating the inflammasome pathway by infecting mouse bone marrow-derived macrophages and human THP-1 macrophage-like cells with a panel of isogenic GAS mutant strains. We found that the cytolysins streptolysin O (SLO) and streptolysin S are the main drivers of IL-1β release in proliferating logarithmic phase GAS. Using a mutant form of recombinant SLO, we confirmed that bacterial pore formation on host cell membranes is a key mechanism required for inflammasome activation. Our results suggest that streptolysins are major determinants of GAS-induced inflammation and present an attractive target for therapeutic intervention.
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Affiliation(s)
- Johanna Richter
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD, Australia
| | - Mercedes M Monteleone
- Australian Infectious Diseases Research Centre, Institute for Molecular Bioscience and IMB Centre for Inflammation and Disease Research, The University of Queensland, St Lucia, QLD, Australia
| | - Amanda J Cork
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD, Australia
| | - Timothy C Barnett
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD, Australia.,Wesfarmers Centre for Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia, Nedlands, WA, Australia
| | - Victor Nizet
- Department of Pediatrics, University of California at San Diego School of Medicine, La Jolla, CA, USA.,Skaggs School of Pharmaceutical Sciences, University of California at San Diego, La Jolla, CA, USA
| | - Stephan Brouwer
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD, Australia
| | - Kate Schroder
- Australian Infectious Diseases Research Centre, Institute for Molecular Bioscience and IMB Centre for Inflammation and Disease Research, The University of Queensland, St Lucia, QLD, Australia
| | - Mark J Walker
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD, Australia
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17
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Alves-Barroco C, Caço J, Roma-Rodrigues C, Fernandes AR, Bexiga R, Oliveira M, Chambel L, Tenreiro R, Mato R, Santos-Sanches I. New Insights on Streptococcus dysgalactiae subsp. dysgalactiae Isolates. Front Microbiol 2021; 12:686413. [PMID: 34335512 PMCID: PMC8319831 DOI: 10.3389/fmicb.2021.686413] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 06/15/2021] [Indexed: 12/14/2022] Open
Abstract
Streptococcus dysgalactiae subsp. dysgalactiae (SDSD) has been considered a strict animal pathogen. Nevertheless, the recent reports of human infections suggest a niche expansion for this subspecies, which may be a consequence of the virulence gene acquisition that increases its pathogenicity. Previous studies reported the presence of virulence genes of Streptococcus pyogenes phages among bovine SDSD (collected in 2002-2003); however, the identity of these mobile genetic elements remains to be clarified. Thus, this study aimed to characterize the SDSD isolates collected in 2011-2013 and compare them with SDSD isolates collected in 2002-2003 and pyogenic streptococcus genomes available at the National Center for Biotechnology Information (NCBI) database, including human SDSD and S. dysgalactiae subsp. equisimilis (SDSE) strains to track temporal shifts on bovine SDSD genotypes. The very close genetic relationships between humans SDSD and SDSE were evident from the analysis of housekeeping genes, while bovine SDSD isolates seem more divergent. The results showed that all bovine SDSD harbor Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas IIA system. The widespread presence of this system among bovine SDSD isolates, high conservation of repeat sequences, and the polymorphism observed in spacer can be considered indicators of the system activity. Overall, comparative analysis shows that bovine SDSD isolates carry speK, speC, speL, speM, spd1, and sdn virulence genes of S. pyogenes prophages. Our data suggest that these genes are maintained over time and seem to be exclusively a property of bovine SDSD strains. Although the bovine SDSD genomes characterized in the present study were not sequenced, the data set, including the high homology of superantigens (SAgs) genes between bovine SDSD and S. pyogenes strains, may indicate that events of horizontal genetic transfer occurred before habitat separation. All bovine SDSD isolates were negative for genes of operon encoding streptolysin S, except for sagA gene, while the presence of this operon was detected in all SDSE and human SDSD strains. The data set of this study suggests that the separation between the subspecies "dysgalactiae" and "equisimilis" should be reconsidered. However, a study including the most comprehensive collection of strains from different environments would be required for definitive conclusions regarding the two taxa.
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Affiliation(s)
- Cinthia Alves-Barroco
- UCIBIO, Departamento de Ciências da Vida, NOVA School of Science and Technology/FCT NOVA, Universidade NOVA de Lisboa, Caparica, Portugal
| | - João Caço
- UCIBIO, Departamento de Ciências da Vida, NOVA School of Science and Technology/FCT NOVA, Universidade NOVA de Lisboa, Caparica, Portugal
| | - Catarina Roma-Rodrigues
- UCIBIO, Departamento de Ciências da Vida, NOVA School of Science and Technology/FCT NOVA, Universidade NOVA de Lisboa, Caparica, Portugal
| | - Alexandra R Fernandes
- UCIBIO, Departamento de Ciências da Vida, NOVA School of Science and Technology/FCT NOVA, Universidade NOVA de Lisboa, Caparica, Portugal
| | - Ricardo Bexiga
- Centro de Investigação Interdisciplinar em Sanidade Animal, Faculdade de Medicina Veterinária, Universidade de Lisboa, Lisbon, Portugal
| | - Manuela Oliveira
- Centro de Investigação Interdisciplinar em Sanidade Animal, Faculdade de Medicina Veterinária, Universidade de Lisboa, Lisbon, Portugal
| | - Lélia Chambel
- Biosystems and Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Edifício TecLabs, Lisbon, Portugal
| | - Rogério Tenreiro
- Biosystems and Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Edifício TecLabs, Lisbon, Portugal
| | - Rosario Mato
- UCIBIO, Departamento de Ciências da Vida, NOVA School of Science and Technology/FCT NOVA, Universidade NOVA de Lisboa, Caparica, Portugal
| | - Ilda Santos-Sanches
- UCIBIO, Departamento de Ciências da Vida, NOVA School of Science and Technology/FCT NOVA, Universidade NOVA de Lisboa, Caparica, Portugal
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18
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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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Hirose Y, Yamaguchi M, Sumitomo T, Nakata M, Hanada T, Okuzaki D, Motooka D, Mori Y, Kawasaki H, Coady A, Uchiyama S, Hiraoka M, Zurich RH, Amagai M, Nizet V, Kawabata S. Streptococcus pyogenes upregulates arginine catabolism to exert its pathogenesis on the skin surface. Cell Rep 2021; 34:108924. [PMID: 33789094 PMCID: PMC9214650 DOI: 10.1016/j.celrep.2021.108924] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 01/15/2021] [Accepted: 03/09/2021] [Indexed: 10/21/2022] Open
Abstract
The arginine deiminase (ADI) pathway has been found in many kinds of bacteria and functions to supplement energy production and provide protection against acid stress. The Streptococcus pyogenes ADI pathway is upregulated upon exposure to various environmental stresses, including glucose starvation. However, there are several unclear points about the advantages to the organism for upregulating arginine catabolism. We show that the ADI pathway contributes to bacterial viability and pathogenesis under low-glucose conditions. S. pyogenes changes global gene expression, including upregulation of virulence genes, by catabolizing arginine. In a murine model of epicutaneous infection, S. pyogenes uses the ADI pathway to augment its pathogenicity by increasing the expression of virulence genes, including those encoding the exotoxins. We also find that arginine from stratum-corneum-derived filaggrin is a key substrate for the ADI pathway. In summary, arginine is a nutrient source that promotes the pathogenicity of S. pyogenes on the skin.
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Affiliation(s)
- Yujiro Hirose
- Department of Oral and Molecular Microbiology, Osaka University Graduate School of Dentistry, Suita, Osaka 565-0871, Japan; Department of Pediatrics, University of California at San Diego School of Medicine, La Jolla, CA 92093, USA.
| | - Masaya Yamaguchi
- Department of Oral and Molecular Microbiology, Osaka University Graduate School of Dentistry, Suita, Osaka 565-0871, Japan
| | - Tomoko Sumitomo
- Department of Oral and Molecular Microbiology, Osaka University Graduate School of Dentistry, Suita, Osaka 565-0871, Japan
| | - Masanobu Nakata
- Department of Oral Microbiology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8544, Japan
| | - Tomoki Hanada
- Department of Oral and Molecular Microbiology, Osaka University Graduate School of Dentistry, Suita, Osaka 565-0871, Japan
| | - Daisuke Okuzaki
- Genome Information Research Center, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan
| | - Daisuke Motooka
- Department of Infection Metagenomics, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan
| | - Yasushi Mori
- Department of Oral and Molecular Microbiology, Osaka University Graduate School of Dentistry, Suita, Osaka 565-0871, Japan
| | - Hiroshi Kawasaki
- Department of Dermatology, Keio University School of Medicine, Tokyo 160-8582, Japan; Immunology Data Integration Unit, RIKEN Medical Sciences Innovation Hub Program, Yokohama 230-0045, Japan; Laboratory for Skin Homeostasis, RIKEN Center for Integrative Medical Sciences, Yokohama 230-0045, Japan
| | - Alison Coady
- Department of Pediatrics, University of California at San Diego School of Medicine, La Jolla, CA 92093, USA
| | - Satoshi Uchiyama
- Department of Pediatrics, University of California at San Diego School of Medicine, La Jolla, CA 92093, USA
| | - Masanobu Hiraoka
- Department of Pediatrics, University of California at San Diego School of Medicine, La Jolla, CA 92093, USA; Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, Wakayama, Wakayama 641-8509, Japan
| | - Raymond H Zurich
- Department of Pediatrics, University of California at San Diego School of Medicine, La Jolla, CA 92093, USA
| | - Masayuki Amagai
- Department of Dermatology, Keio University School of Medicine, Tokyo 160-8582, Japan; Laboratory for Skin Homeostasis, RIKEN Center for Integrative Medical Sciences, Yokohama 230-0045, Japan
| | - Victor Nizet
- Department of Pediatrics, University of California at San Diego School of Medicine, La Jolla, CA 92093, USA; Skaggs School of Pharmaceutical Sciences, University of California at San Diego, La Jolla, CA 92093, USA
| | - Shigetada Kawabata
- Department of Oral and Molecular Microbiology, Osaka University Graduate School of Dentistry, Suita, Osaka 565-0871, Japan.
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20
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Zheng Y, Chen J, Chen L, Hu T, Shi L, Wan S, Wang M. Analysis and control of microbial gas production in fermented chili paste. J FOOD PROCESS PRES 2020. [DOI: 10.1111/jfpp.14806] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yu Zheng
- State Key Laboratory of Food Nutrition and Safety Key Laboratory of Industrial Fermentation Microbiology Ministry of Education College of Biotechnology Tianjin University of Science and Technology Tianjin China
| | - Ju Chen
- State Key Laboratory of Food Nutrition and Safety Key Laboratory of Industrial Fermentation Microbiology Ministry of Education College of Biotechnology Tianjin University of Science and Technology Tianjin China
| | - Lin Chen
- State Key Laboratory of Food Nutrition and Safety Key Laboratory of Industrial Fermentation Microbiology Ministry of Education College of Biotechnology Tianjin University of Science and Technology Tianjin China
| | - Tao Hu
- State Key Laboratory of Food Nutrition and Safety Key Laboratory of Industrial Fermentation Microbiology Ministry of Education College of Biotechnology Tianjin University of Science and Technology Tianjin China
| | - Lei Shi
- Tianjin Limin Condiment Limited Company Tianjin China
| | - Shoupeng Wan
- Tianjin Limin Condiment Limited Company Tianjin China
| | - Min Wang
- State Key Laboratory of Food Nutrition and Safety Key Laboratory of Industrial Fermentation Microbiology Ministry of Education College of Biotechnology Tianjin University of Science and Technology Tianjin China
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21
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Malerba M, Louis S, Cuvellier S, Shambat SM, Hua C, Gomart C, Fouet A, Ortonne N, Decousser JW, Zinkernagel AS, Mathieu JR, Peyssonnaux C. Epidermal hepcidin is required for neutrophil response to bacterial infection. J Clin Invest 2020; 130:329-334. [PMID: 31600168 PMCID: PMC6934188 DOI: 10.1172/jci126645] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 10/02/2019] [Indexed: 01/21/2023] Open
Abstract
Novel approaches for adjunctive therapy are urgently needed for complicated infections and patients with compromised immunity. Necrotizing fasciitis (NF) is a destructive skin and soft tissue infection. Despite treatment with systemic antibiotics and radical debridement of necrotic tissue, lethality remains high. The key iron regulatory hormone hepcidin was originally identified as a cationic antimicrobial peptide (AMP), but its putative expression and role in the skin, a major site of AMP production, have never been investigated. We report here that hepcidin production is induced in the skin of patients with group A Streptococcus (GAS) NF. In a GAS-induced NF model, mice lacking hepcidin in keratinocytes failed to restrict systemic spread of infection from an initial tissue focus. Unexpectedly, this effect was due to its ability to promote production of the CXCL1 chemokine by keratinocytes, resulting in neutrophil recruitment. Unlike CXCL1, hepcidin is resistant to degradation by major GAS proteases and could therefore serve as a reservoir to maintain steady-state levels of CXCL1 in infected tissue. Finally, injection of synthetic hepcidin at the site of infection can limit or completely prevent systemic spread of GAS infection, suggesting that hepcidin agonists could have a therapeutic role in NF.
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Affiliation(s)
- Mariangela Malerba
- Université de Paris, Institut Cochin, INSERM, CNRS, F-75014 Paris, France.,Laboratory of Excellence GR-Ex, Paris, France
| | - Sabine Louis
- Université de Paris, Institut Cochin, INSERM, CNRS, F-75014 Paris, France.,Laboratory of Excellence GR-Ex, Paris, France
| | - Sylvain Cuvellier
- Université de Paris, Institut Cochin, INSERM, CNRS, F-75014 Paris, France.,Laboratory of Excellence GR-Ex, Paris, France
| | - Srikanth Mairpady Shambat
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Camille Hua
- Service de Dermatologie, Assistance Publique-Hôpitaux de Paris, Paris, France.,Hôpital Henri Mondor, Assistance Publique-Hôpitaux de Paris, Créteil, France.,EA 7379 EPiderME, Université Paris Est Créteil, Créteil, France
| | - Camille Gomart
- Hôpital Henri Mondor, Assistance Publique-Hôpitaux de Paris, Créteil, France.,Laboratoire de Bactériologie Hygiène and.,Equipe Opérationnelle d'Hygiène, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Agnès Fouet
- Université de Paris, Institut Cochin, INSERM, CNRS, F-75014 Paris, France
| | - Nicolas Ortonne
- EA 7380 Dynamyc, Université Paris-Est Créteil, Créteil, France.,Ecole Nationale Vétérinaire d'Alfort (EnvA), Maisons-Alfort, France
| | - Jean-Winoc Decousser
- Hôpital Henri Mondor, Assistance Publique-Hôpitaux de Paris, Créteil, France.,Laboratoire de Bactériologie Hygiène and.,Equipe Opérationnelle d'Hygiène, Assistance Publique-Hôpitaux de Paris, Paris, France.,EA 7380 Dynamyc, Université Paris-Est Créteil, Créteil, France.,Faculté de Médecine de Créteil, Université Paris Est Créteil, Créteil, France.,Pathology Department, Henri Mondor Hospital, Assistance Publique-Hôpitaux de Paris, Créteil, France
| | - Annelies S Zinkernagel
- Université de Paris, Institut Cochin, INSERM, CNRS, F-75014 Paris, France.,Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Jacques Rr Mathieu
- Université de Paris, Institut Cochin, INSERM, CNRS, F-75014 Paris, France.,Laboratory of Excellence GR-Ex, Paris, France
| | - Carole Peyssonnaux
- Université de Paris, Institut Cochin, INSERM, CNRS, F-75014 Paris, France.,Laboratory of Excellence GR-Ex, Paris, France
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22
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Live Cell Microscopy and Flow Cytometry to Study Streptolysin S-Mediated Erythrocyte Hemolysis. Methods Mol Biol 2020. [PMID: 32430826 DOI: 10.1007/978-1-0716-0467-0_18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
The ability to induce hemolysis, the rupturing of erythrocytes with the consequent release of their intracellular contents, is a phenotypic hallmark of a number of microbial toxins. Streptococcus pyogenes or Group A Streptococcus (GAS) is a human pathogen responsible for a wide range of diseases from mild pharyngitis to severe conditions such as toxic shock syndrome. GAS produces a powerful hemolytic toxin called streptolysin S (SLS). Herein, we describe a procedure for the preparation of SLS toxin and the use of two complementary approaches, live microscopy and flow cytometry, to study the effects of the SLS toxin on erythrocytes. In addition to providing insights into SLS-mediated hemolysis, these assays have the potential to be modified for the study of other hemolytic toxins and compounds.
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23
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Bacteriocins of Listeria monocytogenes and Their Potential as a Virulence Factor. Toxins (Basel) 2020; 12:toxins12020103. [PMID: 32033406 PMCID: PMC7076858 DOI: 10.3390/toxins12020103] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 01/27/2020] [Accepted: 02/03/2020] [Indexed: 12/28/2022] Open
Abstract
Intestinal microbiota exerts protective effects against the infection of various bacterial pathogens, including Listeria monocytogenes, a major foodborne pathogen whose infection can lead to a disease (listeriosis) with a high fatality rate. As a strategy to mitigate the action of the intestinal microbiota, pathogens often produce antimicrobial proteinaceous compounds such as bacteriocins. In this review, we summarize the information currently available for the well-characterized L. monocytogenes bacteriocin listeriolysin S, with the emphasis on its intriguing mode of action as a virulence factor, which promotes the infection of L. monocytogenes by changing the composition of the intestinal microbiota. We then discuss another intriguing L. monocytogenes bacteriocin Lmo2776 that specifically inhibits the inflammogenic species, Prevotella copri, in the intestinal microbiota, reducing superfluous inflammation while weakening virulence. In addition, we describe relatively less studied phage tail-like Listeria bacteriocins (monocins) and elaborate on the possibility that these monocins could be involved in enhancing pathogenicity. In spite of the burgeoning interest in the roles played by the intestinal microbiota against the L. monocytogenes infection, our understanding on the virulence factors affecting the intestinal microbiota is still lacking, calling for further studies on bacteriocins that could function as novel virulence factors.
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24
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Streptococcus pyogenes Transcriptome Changes in the Inflammatory Environment of Necrotizing Fasciitis. Appl Environ Microbiol 2019; 85:AEM.01428-19. [PMID: 31471300 PMCID: PMC6803311 DOI: 10.1128/aem.01428-19] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 08/23/2019] [Indexed: 12/31/2022] Open
Abstract
Necrotizing fasciitis, a life-threatening subcutaneous soft-tissue infection, is principally caused by S. pyogenes. The inflammatory environment at the site of infection causes global gene expression changes for survival of the bacterium and pathogenesis. However, no known study regarding transcriptomic profiling of S. pyogenes in cases of necrotizing fasciitis has been presented. We identified 483 bacterial genes whose expression was consistently altered during infection. Our results showed that S. pyogenes infection induces drastic upregulation of the expression of virulence-associated genes and shifts metabolic pathway usage. In particular, high-level expression of toxins, such as cytolysins, proteases, and nucleases, was observed at infection sites. In addition, genes identified as consistently enriched included those related to metabolism of arginine and histidine as well as carbohydrate uptake and utilization. Conversely, genes associated with the oxidative stress response and cell division were consistently downregulated during infection. The present findings provide useful information for establishing novel treatment strategies. Streptococcus pyogenes is a major cause of necrotizing fasciitis, a life-threatening subcutaneous soft-tissue infection. At the host infection site, the local environment and interactions between the host and bacteria have effects on bacterial gene expression profiles, while the gene expression pattern of S. pyogenes related to this disease remains unknown. In this study, we used a mouse model of necrotizing fasciitis and performed RNA-sequencing (RNA-seq) analysis of S. pyogenes M1T1 strain 5448 by isolating total RNA from infected hind limbs obtained at 24, 48, and 96 h postinfection. RNA-seq analysis results identified 483 bacterial genes whose expression was consistently altered in the infected hindlimbs compared to their expression under in vitro conditions. Genes showing consistent enrichment during infection included 306 encoding molecules involved in virulence, carbohydrate utilization, amino acid metabolism, trace-metal transport, and the vacuolar ATPase transport system. Surprisingly, drastic upregulation of 3 genes, encoding streptolysin S precursor (sagA), cysteine protease (speB), and secreted DNase (spd), was noted in the present mouse model (log2 fold change, >6.0, >9.4, and >7.1, respectively). Conversely, the number of consistently downregulated genes was 177, including those associated with the oxidative stress response and cell division. These results suggest that in necrotizing fasciitis, S. pyogenes shows an altered metabolism, decreased cell proliferation, and upregulation of expression of major toxins. Our findings are considered to provide critical information for developing novel treatment strategies and vaccines for necrotizing fasciitis. IMPORTANCE Necrotizing fasciitis, a life-threatening subcutaneous soft-tissue infection, is principally caused by S. pyogenes. The inflammatory environment at the site of infection causes global gene expression changes for survival of the bacterium and pathogenesis. However, no known study regarding transcriptomic profiling of S. pyogenes in cases of necrotizing fasciitis has been presented. We identified 483 bacterial genes whose expression was consistently altered during infection. Our results showed that S. pyogenes infection induces drastic upregulation of the expression of virulence-associated genes and shifts metabolic pathway usage. In particular, high-level expression of toxins, such as cytolysins, proteases, and nucleases, was observed at infection sites. In addition, genes identified as consistently enriched included those related to metabolism of arginine and histidine as well as carbohydrate uptake and utilization. Conversely, genes associated with the oxidative stress response and cell division were consistently downregulated during infection. The present findings provide useful information for establishing novel treatment strategies.
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25
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Wolfsberger CH, Pfurtscheller K, Ulreich R, Pocivalnik M, Vasilyeva A, Schintler MV. Incomplete limb ischemia as a complication in a pediatric patient with toxic-shock syndrome. JOURNAL OF PEDIATRIC SURGERY CASE REPORTS 2019. [DOI: 10.1016/j.epsc.2019.101282] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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26
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The Role of Streptococcal and Staphylococcal Exotoxins and Proteases in Human Necrotizing Soft Tissue Infections. Toxins (Basel) 2019; 11:toxins11060332. [PMID: 31212697 PMCID: PMC6628391 DOI: 10.3390/toxins11060332] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 06/04/2019] [Accepted: 06/10/2019] [Indexed: 12/31/2022] Open
Abstract
Necrotizing soft tissue infections (NSTIs) are critical clinical conditions characterized by extensive necrosis of any layer of the soft tissue and systemic toxicity. Group A streptococci (GAS) and Staphylococcus aureus are two major pathogens associated with monomicrobial NSTIs. In the tissue environment, both Gram-positive bacteria secrete a variety of molecules, including pore-forming exotoxins, superantigens, and proteases with cytolytic and immunomodulatory functions. The present review summarizes the current knowledge about streptococcal and staphylococcal toxins in NSTIs with a special focus on their contribution to disease progression, tissue pathology, and immune evasion strategies.
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27
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Streptolysin S induces mitochondrial damage and macrophage death through inhibiting degradation of glycogen synthase kinase-3β in Streptococcus pyogenes infection. Sci Rep 2019; 9:5371. [PMID: 30926881 PMCID: PMC6440947 DOI: 10.1038/s41598-019-41853-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 03/18/2019] [Indexed: 12/20/2022] Open
Abstract
Group A Streptococcus (GAS) infection is associated with a variety of human diseases. Previous studies indicate GAS infection leads to RAW264.7 cell death, but the mechanism is unclear. Here, analyzing the timing of reactive oxygen species (ROS) production and using mitochondrial ROS scavenger, we found the wild type GAS-induced RAW264.7 cell death was associated with mitochondrial ROS. The wild type GAS infection could activate glycogen synthase kinase-3β (GSK-3β). Inhibition of GSK-3β activity by lithium chloride or decreasing GSK-3β expression by lentivirus-mediated short hairpin RNA for GSK-3β could not only decrease the wild type GAS-induced mitochondrial ROS generation, mitochondria damage and cell death, but also reduced GAS intracellular replication. Streptolysin S (SLS), a GAS toxin, played the important role on GAS-induced macrophage death. Compared to the wild type GAS with its isogenic sagB mutant (SLS mutant)-infected macrophages, we found sagB mutant infection caused less mitochondrial ROS generation and cell death than those of the wild type GAS-infected ones. Furthermore, the sagB mutant, but not the wild type or the sagB-complementary mutant, could induce GSK-3β degradation via a proteasome-dependent pathway. These results suggest that a new mechanism of SLS-induced macrophage death was through inhibiting GSK-3β degradation and further enhancing mitochondrial damage.
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28
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Abstract
ABSTRACT
Streptococcus pyogenes
(i.e., the group A
Streptococcus
) is a human-restricted and versatile bacterial pathogen that produces an impressive arsenal of both surface-expressed and secreted virulence factors. Although surface-expressed virulence factors are clearly vital for colonization, establishing infection, and the development of disease, the secreted virulence factors are likely the major mediators of tissue damage and toxicity seen during active infection. The collective exotoxin arsenal of
S. pyogenes
is rivaled by few bacterial pathogens and includes extracellular enzymes, membrane active proteins, and a variety of toxins that specifically target both the innate and adaptive arms of the immune system, including the superantigens; however, despite their role in
S. pyogenes
disease, each of these virulence factors has likely evolved with humans in the context of asymptomatic colonization and transmission. In this article, we focus on the biology of the true secreted exotoxins of the group A
Streptococcus
, as well as their roles in the pathogenesis of human disease.
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29
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Raina M, King A, Bianco C, Vanderpool CK. Dual-Function RNAs. Microbiol Spectr 2018; 6:10.1128/microbiolspec.RWR-0032-2018. [PMID: 30191807 PMCID: PMC6130917 DOI: 10.1128/microbiolspec.rwr-0032-2018] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Indexed: 12/30/2022] Open
Abstract
Bacteria are known to use RNA, either as mRNAs encoding proteins or as noncoding small RNAs (sRNAs), to regulate numerous biological processes. However, a few sRNAs have two functions: they act as base-pairing RNAs and encode a small protein with additional regulatory functions. Thus, these so called "dual-function" sRNAs can serve as both a riboregulator and an mRNA. In some cases, these two functions can act independently within the same pathway, while in other cases, the base-pairing function and protein function act in different pathways. Here, we discuss the five known dual-function sRNAs-SgrS from enteric species, RNAIII and Psm-mec from Staphylococcus aureus, Pel RNA from Streptococcus pyogenes, and SR1 from Bacillus subtilis-and review their mechanisms of action and roles in regulating diverse biological processes. We also discuss the prospect of finding additional dual-function sRNAs and future challenges in studying the overlap and competition between the functions.
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Affiliation(s)
- Medha Raina
- Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD 20892
| | - Alisa King
- Department of Microbiology, University of Illinois, Urbana, IL 61801
| | - Colleen Bianco
- Department of Microbiology, University of Illinois, Urbana, IL 61801
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30
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Flaherty RA, Donahue DL, Carothers KE, Ross JN, Ploplis VA, Castellino FJ, Lee SW. Neutralization of Streptolysin S-Dependent and Independent Inflammatory Cytokine IL-1β Activity Reduces Pathology During Early Group A Streptococcal Skin Infection. Front Cell Infect Microbiol 2018; 8:211. [PMID: 30018884 PMCID: PMC6037840 DOI: 10.3389/fcimb.2018.00211] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 06/05/2018] [Indexed: 12/12/2022] Open
Abstract
The bacterial pathogen Group A Streptococcus (GAS) has been shown to induce a variety of human diseases ranging in severity from pharyngitis to toxic shock syndrome and necrotizing fasciitis. GAS produces a powerful peptide toxin known as Streptolysin S (SLS). Though long recognized as a potent cytolysin, recent evidence from our lab has shown that SLS-dependent cytotoxicity is mediated through activation of the pro-inflammatory mediators p38 MAPK and NFκB. These findings led us to hypothesize that activation of p38 MAPK and NFκB signaling drive the production of pro-inflammatory cytokines which, in turn, serve as positive feedback signals to initiate cytotoxicity in infected host cells. To address this hypothesis, we utilized a cytokine array to characterize the SLS-dependent pro-inflammatory cytokine response to GAS infection in human keratinocytes. From these studies, IL-1β was found to be markedly upregulated in the presence of SLS, and further investigation revealed that this cytokine contributes to cytotoxicity in human keratinocytes during infection. Subcutaneous infection studies were performed in mice to address the physiological impact of increased IL-1β production. These studies demonstrated that IL-1β is produced during GAS skin infection in an SLS-dependent manner. Furthermore, inhibition of this cytokine and the upstream kinases and other signaling mediators that drive its production reduced SLS-mediated lesion formation early in the infection process. Together, our findings indicate that pharmacological inhibition of this inflammatory axis holds promise as a therapeutic strategy to reduce tissue destruction during severe invasive Group A Streptococcal infections.
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Affiliation(s)
- Rebecca A Flaherty
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, United States.,Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN, United States
| | - Deborah L Donahue
- W. M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, IN, United States
| | - Katelyn E Carothers
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, United States.,Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN, United States
| | - Jessica N Ross
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, United States.,Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN, United States
| | - Victoria A Ploplis
- W. M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, IN, United States
| | - Francis J Castellino
- W. M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, IN, United States
| | - Shaun W Lee
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, United States.,Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN, United States.,W. M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, IN, United States
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31
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Bauer R, Mauerer S, Spellerberg B. Regulation of the β-hemolysin gene cluster of Streptococcus anginosus by CcpA. Sci Rep 2018; 8:9028. [PMID: 29899560 PMCID: PMC5998137 DOI: 10.1038/s41598-018-27334-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 05/30/2018] [Indexed: 11/09/2022] Open
Abstract
Streptococcus anginosus is increasingly recognized as an opportunistic pathogen. However, our knowledge about virulence determinants in this species is scarce. One exception is the streptolysin-S (SLS) homologue responsible for the β-hemolytic phenotype of the S. anginosus type strain. In S. anginosus the expression of the hemolysin is reduced in the presence of high glucose concentrations. To investigate the genetic mechanism of the hemolysin repression we created an isogenic ccpA deletion strain. In contrast to the wild type strain, this mutant exhibits hemolytic activity in presence of up to 25 mM glucose supplementation, a phenotype that could be reverted by ccpA complementation. To further demonstrate that CcpA directly regulates the hemolysin expression, we performed an in silico analysis of the promoter of the SLS gene cluster and we verified the binding of CcpA to the promoter by electrophoretic mobility shift assays. This allowed us to define the CcpA binding site in the SLS promoter region of S. anginosus. In conclusion, we report for the first time the characterization of a potential virulence regulator in S. anginosus.
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Affiliation(s)
- Richard Bauer
- Institute of Medical Microbiology and Hospital Hygiene, University of Ulm, Ulm, Germany
| | - Stefanie Mauerer
- Institute of Medical Microbiology and Hospital Hygiene, University of Ulm, Ulm, Germany
| | - Barbara Spellerberg
- Institute of Medical Microbiology and Hospital Hygiene, University of Ulm, Ulm, Germany.
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32
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Soor HS, Appavoo SD, Yudin AK. Heterocycles: Versatile control elements in bioactive macrocycles. Bioorg Med Chem 2018; 26:2774-2779. [DOI: 10.1016/j.bmc.2017.10.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 10/13/2017] [Accepted: 10/17/2017] [Indexed: 10/18/2022]
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33
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Blocking Neuronal Signaling to Immune Cells Treats Streptococcal Invasive Infection. Cell 2018; 173:1083-1097.e22. [PMID: 29754819 DOI: 10.1016/j.cell.2018.04.006] [Citation(s) in RCA: 254] [Impact Index Per Article: 42.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Revised: 02/08/2018] [Accepted: 04/03/2018] [Indexed: 11/21/2022]
Abstract
The nervous system, the immune system, and microbial pathogens interact closely at barrier tissues. Here, we find that a bacterial pathogen, Streptococcus pyogenes, hijacks pain and neuronal regulation of the immune response to promote bacterial survival. Necrotizing fasciitis is a life-threatening soft tissue infection in which "pain is out of proportion" to early physical manifestations. We find that S. pyogenes, the leading cause of necrotizing fasciitis, secretes streptolysin S (SLS) to directly activate nociceptor neurons and produce pain during infection. Nociceptors, in turn, release the neuropeptide calcitonin gene-related peptide (CGRP) into infected tissues, which inhibits the recruitment of neutrophils and opsonophagocytic killing of S. pyogenes. Botulinum neurotoxin A and CGRP antagonism block neuron-mediated suppression of host defense, thereby preventing and treating S. pyogenes necrotizing infection. We conclude that targeting the peripheral nervous system and blocking neuro-immune communication is a promising strategy to treat highly invasive bacterial infections. VIDEO ABSTRACT.
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34
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Virulence Role of the GlcNAc Side Chain of the Lancefield Cell Wall Carbohydrate Antigen in Non-M1-Serotype Group A Streptococcus. mBio 2018; 9:mBio.02294-17. [PMID: 29382733 PMCID: PMC5790915 DOI: 10.1128/mbio.02294-17] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Classification of streptococci is based upon expression of unique cell wall carbohydrate antigens. All serotypes of group A Streptococcus (GAS; Streptococcus pyogenes), a leading cause of infection-related mortality worldwide, express the group A carbohydrate (GAC). GAC, the classical Lancefield antigen, is comprised of a polyrhamnose backbone with N-acetylglucosamine (GlcNAc) side chains. The immunodominant GlcNAc epitope of GAC is the basis of all rapid diagnostic testing for GAS infection. We previously identified the 12-gene GAC biosynthesis gene cluster and determined that the glycosyltransferase GacI was required for addition of the GlcNAc side chain to the polyrhamnose core. Loss of the GAC GlcNAc epitope in serotype M1 GAS resulted in attenuated virulence in two animal infection models and increased GAS sensitivity to killing by whole human blood, serum, neutrophils, and antimicrobial peptides. Here, we report that the GAC biosynthesis gene cluster is ubiquitous among 520 GAS isolates from global sources, representing 105 GAS emm serotypes. Isogenic ΔgacI mutants were constructed in M2, M3, M4, M28, and M89 backgrounds and displayed an array of phenotypes in susceptibility to killing by whole human blood, baby rabbit serum, human platelet releasate, human neutrophils, and antimicrobial peptide LL-37. The contribution of the GlcNAc side chain to GAS survival in vivo also varied by strain, demonstrating that it is not a prerequisite for virulence in the murine infection model. Thus, the relative contribution of GAC to virulence in non-M1 serotypes appears to depend on the quorum of other virulence factors that each strain possesses.IMPORTANCE The Lancefield group A carbohydrate (GAC) is the species-defining antigen for group A Streptococcus (GAS), comprising ~50% of the cell wall of this major human pathogen. We previously showed that the GlcNAc side chain of GAC contributes to the innate immune resistance and animal virulence phenotypes of the globally disseminated strain of serotype M1 GAS. Here, we use isogenic mutagenesis to examine the role of GAC GlcNAc in five additional medically relevant GAS serotypes. Overall, the GlcNAc side chain of GAC contributes to the innate immune resistance of GAS, but the relative contribution varies among individual strains. Moreover, the GAC GlcNAc side chain is not a universal prerequisite for GAS virulence in the animal model.
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35
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Requirement and Synergistic Contribution of Platelet-Activating Factor Acetylhydrolase Sse and Streptolysin S to Inhibition of Neutrophil Recruitment and Systemic Infection by Hypervirulent emm3 Group A Streptococcus in Subcutaneous Infection of Mice. Infect Immun 2017; 85:IAI.00530-17. [PMID: 28947648 DOI: 10.1128/iai.00530-17] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Accepted: 09/18/2017] [Indexed: 01/18/2023] Open
Abstract
Hypervirulent group A streptococcus (GAS) can inhibit neutrophil recruitment and cause systemic infection in a mouse model of skin infection. The purpose of this study was to determine whether platelet-activating factor acetylhydrolase Sse and streptolysin S (SLS) have synergistic contributions to inhibition of neutrophil recruitment and systemic infection in subcutaneous infection of mice by MGAS315, a hypervirulent genotype emm3 GAS strain. Deletion of sse and sagA in MGAS315 synergistically reduced the skin lesion size and GAS burden in the liver and spleen. However, the mutants were persistent at skin sites and had similar growth factors in nonimmune blood. Thus, the low numbers of Δsse ΔsagA mutants in the liver and spleen were likely due to their reduction in the systemic dissemination. Few intact and necrotic neutrophils were detected at MGAS315 infection sites. In contrast, many neutrophils and necrotic cells were present at the edge of Δsse mutant infection sites on day 1 and at the edge of and inside Δsse mutant infection sites on day 2. ΔsagA mutant infection sites had massive numbers of and few intact neutrophils at the edge and center of the infection sites, respectively, on day 1 and were full of intact neutrophils or necrotic cells on day 2. Δsse ΔsagA mutant infection sites had massive numbers of intact neutrophils throughout the whole infection site. These sse and sagA deletion-caused changes in the histological pattern at skin infection sites could be complemented. Thus, the sse and sagA deletions synergistically enhance neutrophil recruitment. These findings indicate that both Sse and SLS are required but that neither is sufficient for inhibition of neutrophil recruitment and systemic infection by hypervirulent GAS.
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Opacification Domain of Serum Opacity Factor Inhibits Beta-Hemolysis and Contributes to Virulence of Streptococcus pyogenes. mSphere 2017; 2:mSphere00147-17. [PMID: 28435893 PMCID: PMC5397570 DOI: 10.1128/mspheredirect.00147-17] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 04/01/2017] [Indexed: 11/25/2022] Open
Abstract
Streptococcus pyogenes is a major human pathogen causing more than 700 million infections annually. As a successful pathogen, S. pyogenes produces many virulence factors that facilitate colonization, proliferation, dissemination, and tissue damage. Serum opacity factor (SOF), an extracellular protein, is one of the virulence factors made by S. pyogenes. The underlying mechanism of how SOF contributes to virulence is not fully understood. SOF has two major features: (i) it opacifies host serum by interacting with high-density lipoprotein, and (ii) it inhibits beta-hemolysis on blood agar. In this study, we demonstrate that the domain of SOF essential for opacifying serum is also essential for SOF-mediated beta-hemolysis inhibition and SOF-mediated virulence. Our results shed new light on the molecular mechanisms of SOF-host interaction. Serum opacity factor (SOF) is a cell surface virulence factor made by the human pathogen Streptococcus pyogenes. We found that S. pyogenes strains with naturally occurring truncation mutations in the sof gene have markedly enhanced beta-hemolysis. Moreover, deletion of the sof gene in a SOF-positive parental strain resulted in significantly increased beta-hemolysis. Together, these observations suggest that SOF is an inhibitor of beta-hemolysis. SOF has two major functional domains, including an opacification domain and a fibronectin-binding domain. Using a SOF-positive serotype M89 S. pyogenes parental strain and a panel of isogenic mutant derivative strains, we evaluated the relative contribution of each SOF functional domain to beta-hemolysis inhibition and bacterial virulence. We found that the opacification domain, rather than the fibronectin-binding domain, is essential for SOF-mediated beta-hemolysis inhibition. The opacification domain, but not the fibronectin-binding domain of SOF, also contributed significantly to virulence in mouse models of bacteremia and necrotizing myositis. Inasmuch as the opacification domain of SOF is known to interact avidly with host high-density lipoprotein (HDL), we speculate that SOF-HDL interaction is an important process underlying SOF-mediated beta-hemolysis inhibition and SOF-mediated virulence. IMPORTANCEStreptococcus pyogenes is a major human pathogen causing more than 700 million infections annually. As a successful pathogen, S. pyogenes produces many virulence factors that facilitate colonization, proliferation, dissemination, and tissue damage. Serum opacity factor (SOF), an extracellular protein, is one of the virulence factors made by S. pyogenes. The underlying mechanism of how SOF contributes to virulence is not fully understood. SOF has two major features: (i) it opacifies host serum by interacting with high-density lipoprotein, and (ii) it inhibits beta-hemolysis on blood agar. In this study, we demonstrate that the domain of SOF essential for opacifying serum is also essential for SOF-mediated beta-hemolysis inhibition and SOF-mediated virulence. Our results shed new light on the molecular mechanisms of SOF-host interaction.
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Listeriolysin S Is a Streptolysin S-Like Virulence Factor That Targets Exclusively Prokaryotic Cells In Vivo. mBio 2017; 8:mBio.00259-17. [PMID: 28377528 PMCID: PMC5380841 DOI: 10.1128/mbio.00259-17] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Streptolysin S (SLS)-like virulence factors from clinically relevant Gram-positive pathogens have been proposed to behave as potent cytotoxins, playing key roles in tissue infection. Listeriolysin S (LLS) is an SLS-like hemolysin/bacteriocin present among Listeria monocytogenes strains responsible for human listeriosis outbreaks. As LLS cytotoxic activity has been associated with virulence, we investigated the LLS-specific contribution to host tissue infection. Surprisingly, we first show that LLS causes only weak red blood cell (RBC) hemolysis in vitro and neither confers resistance to phagocytic killing nor favors survival of L. monocytogenes within the blood cells or in the extracellular space (in the plasma). We reveal that LLS does not elicit specific immune responses, is not cytotoxic for eukaryotic cells, and does not impact cell infection by L. monocytogenes. Using in vitro cell infection systems and a murine intravenous infection model, we actually demonstrate that LLS expression is undetectable during infection of cells and murine inner organs. Importantly, upon intravenous animal inoculation, L. monocytogenes is found in the gastrointestinal system, and only in this environment LLS expression is detected in vivo. Finally, we confirm that LLS production is associated with destruction of target bacteria. Our results demonstrate therefore that LLS does not contribute to L. monocytogenes tissue injury and virulence in inner host organs as previously reported. Moreover, we describe that LlsB, a putative posttranslational modification enzyme encoded in the LLS operon, is necessary for murine inner organ colonization. Overall, we demonstrate that LLS is the first SLS-like virulence factor targeting exclusively prokaryotic cells during in vivo infections. The most severe human listeriosis outbreaks are caused by L. monocytogenes strains harboring listeriolysin S (LLS), previously described as a cytotoxin that plays a critical role in host inner tissue infection. Cytotoxic activities have been proposed as a general mode of action for streptolysin S (SLS)-like toxins, including clostridiolysin S and LLS. We now challenge this dogma by demonstrating that LLS does not contribute to virulence in vivo once the intestinal barrier has been crossed. Importantly, we show that intravenous L. monocytogenes inoculation leads to bacterial translocation to the gastrointestinal system, where LLS is specifically expressed, targeting the host gut microbiota. Our study highlights the heterogeneous modes of action of SLS-like toxins, and we demonstrate for the first time a further level of complexity for SLS-like biosynthetic clusters as we reveal that the putative posttranslational modification enzyme LlsB is actually required for inner organ colonization, independently of the LLS activity.
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Kuo CF, Tsao N, Hsieh IC, Lin YS, Wu JJ, Hung YT. Immunization with a streptococcal multiple-epitope recombinant protein protects mice against invasive group A streptococcal infection. PLoS One 2017; 12:e0174464. [PMID: 28355251 PMCID: PMC5371370 DOI: 10.1371/journal.pone.0174464] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 03/09/2017] [Indexed: 12/11/2022] Open
Abstract
Streptococcus pyogenes (group A Streptococcus; GAS) causes clinical diseases, including pharyngitis, scarlet fever, impetigo, necrotizing fasciitis and streptococcal toxic shock syndrome. A number of group A streptococcus vaccine candidates have been developed, but only one 26-valent recombinant M protein vaccine has entered clinical trials. Differing from the design of a 26-valent recombinant M protein vaccine, we provide here a vaccination using the polyvalence epitope recombinant FSBM protein (rFSBM), which contains four different epitopes, including the fibronectin-binding repeats domain of streptococcal fibronectin binding protein Sfb1, the C-terminal immunogenic segment of streptolysin S, the C3-binding motif of streptococcal pyrogenic exotoxin B, and the C-terminal conserved segment of M protein. Vaccination with the rFSBM protein successfully prevented mortality and skin lesions caused by several emm strains of GAS infection. Anti-FSBM antibodies collected from the rFSBM-immunized mice were able to opsonize at least six emm strains and can neutralize the hemolytic activity of streptolysin S. Furthermore, the internalization of GAS into nonphagocytic cells is also reduced by anti-FSBM serum. These findings suggest that rFSBM can be applied as a vaccine candidate to prevent different emm strains of GAS infection.
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Affiliation(s)
- Chih-Feng Kuo
- Department of Nursing, College of Medicine, I-Shou University, Kaohsiung, Taiwan
| | - Nina Tsao
- Department of Biological Science and Technology, College of Medicine, I-Shou University, Kaohsiung, Taiwan
| | - I-Chen Hsieh
- Department of Biological Science and Technology, College of Medicine, I-Shou University, Kaohsiung, Taiwan
| | - Yee-Shin Lin
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Jiunn-Jong Wu
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Department of Biotechnology and Laboratory Science in Medicine, School of Biomedical Science and Engineering, National Yang-Ming University, Taipei, Taiwan
| | - Yu-Ting Hung
- Department of Biological Science and Technology, College of Medicine, I-Shou University, Kaohsiung, Taiwan
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Burkhart BJ, Schwalen CJ, Mann G, Naismith JH, Mitchell DA. YcaO-Dependent Posttranslational Amide Activation: Biosynthesis, Structure, and Function. Chem Rev 2017; 117:5389-5456. [PMID: 28256131 DOI: 10.1021/acs.chemrev.6b00623] [Citation(s) in RCA: 134] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
With advances in sequencing technology, uncharacterized proteins and domains of unknown function (DUFs) are rapidly accumulating in sequence databases and offer an opportunity to discover new protein chemistry and reaction mechanisms. The focus of this review, the formerly enigmatic YcaO superfamily (DUF181), has been found to catalyze a unique phosphorylation of a ribosomal peptide backbone amide upon attack by different nucleophiles. Established nucleophiles are the side chains of Cys, Ser, and Thr which gives rise to azoline/azole biosynthesis in ribosomally synthesized and posttranslationally modified peptide (RiPP) natural products. However, much remains unknown about the potential for YcaO proteins to collaborate with other nucleophiles. Recent work suggests potential in forming thioamides, macroamidines, and possibly additional post-translational modifications. This review covers all knowledge through mid-2016 regarding the biosynthetic gene clusters (BGCs), natural products, functions, mechanisms, and applications of YcaO proteins and outlines likely future research directions for this protein superfamily.
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Affiliation(s)
| | | | - Greg Mann
- Biomedical Science Research Complex, University of St Andrews , BSRC North Haugh, St Andrews KY16 9ST, United Kingdom
| | - James H Naismith
- Biomedical Science Research Complex, University of St Andrews , BSRC North Haugh, St Andrews KY16 9ST, United Kingdom.,State Key Laboratory of Biotherapy, Sichuan University , Sichuan, China
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Garg N, Luzzatto-Knaan T, Melnik AV, Caraballo-Rodríguez AM, Floros DJ, Petras D, Gregor R, Dorrestein PC, Phelan VV. Natural products as mediators of disease. Nat Prod Rep 2017; 34:194-219. [PMID: 27874907 PMCID: PMC5299058 DOI: 10.1039/c6np00063k] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Covering: up to 2016Humans are walking microbial ecosystems, each harboring a complex microbiome with the genetic potential to produce a vast array of natural products. Recent sequencing data suggest that our microbial inhabitants are critical for maintaining overall health. Shifts in microbial communities have been correlated to a number of diseases including infections, inflammation, cancer, and neurological disorders. Some of these clinically and diagnostically relevant phenotypes are a result of the presence of small molecules, yet we know remarkably little about their contributions to the health of individuals. Here, we review microbe-derived natural products as mediators of human disease.
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Affiliation(s)
- Neha Garg
- Collaborative Mass Spectrometry Innovation Center, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093
| | - Tal Luzzatto-Knaan
- Collaborative Mass Spectrometry Innovation Center, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093
| | - Alexey V. Melnik
- Collaborative Mass Spectrometry Innovation Center, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093
| | | | - Dimitrios J. Floros
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093
| | - Daniel Petras
- Collaborative Mass Spectrometry Innovation Center, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093
| | - Rachel Gregor
- Department of Chemistry and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Be’er Sheva 84105, Israel
| | - Pieter C. Dorrestein
- Collaborative Mass Spectrometry Innovation Center, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093
| | - Vanessa V. Phelan
- Collaborative Mass Spectrometry Innovation Center, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, The University of Colorado Anschutz Medical Campus, Aurora, CO 80045
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41
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Efstratiou A, Lamagni T, Turner CE. Streptococci and Enterococci. Infect Dis (Lond) 2017. [DOI: 10.1016/b978-0-7020-6285-8.00177-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Viszwapriya D, Subramenium GA, Prithika U, Balamurugan K, Pandian SK. Betulin inhibits virulence and biofilm ofStreptococcus pyogenesby suppressingropBcore regulon,sagAanddltA. Pathog Dis 2016; 74:ftw088. [DOI: 10.1093/femspd/ftw088] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/01/2016] [Indexed: 12/21/2022] Open
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Flaherty RA, Lee SW. Implementation of a Permeable Membrane Insert-based Infection System to Study the Effects of Secreted Bacterial Toxins on Mammalian Host Cells. J Vis Exp 2016. [PMID: 27585035 PMCID: PMC5091927 DOI: 10.3791/54406] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Many bacterial pathogens secrete potent toxins to aid in the destruction of host tissue, to initiate signaling changes in host cells or to manipulate immune system responses during the course of infection. Though methods have been developed to successfully purify and produce many of these important virulence factors, there are still many bacterial toxins whose unique structure or extensive post-translational modifications make them difficult to purify and study in in vitro systems. Furthermore, even when pure toxin can be obtained, there are many challenges associated with studying the specific effects of a toxin under relevant physiological conditions. Most in vitro cell culture models designed to assess the effects of secreted bacterial toxins on host cells involve incubating host cells with a one-time dose of toxin. Such methods poorly approximate what host cells actually experience during an infection, where toxin is continually produced by bacterial cells and allowed to accumulate gradually during the course of infection. This protocol describes the design of a permeable membrane insert-based bacterial infection system to study the effects of Streptolysin S, a potent toxin produced by Group A Streptococcus, on human epithelial keratinocytes. This system more closely mimics the natural physiological environment during an infection than methods where pure toxin or bacterial supernatants are directly applied to host cells. Importantly, this method also eliminates the bias of host responses that are due to direct contact between the bacteria and host cells. This system has been utilized to effectively assess the effects of Streptolysin S (SLS) on host membrane integrity, cellular viability, and cellular signaling responses. This technique can be readily applied to the study of other secreted virulence factors on a variety of mammalian host cell types to investigate the specific role of a secreted bacterial factor during the course of infection.
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Affiliation(s)
- Rebecca A Flaherty
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame
| | - Shaun W Lee
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame;
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Affiliation(s)
- Simon Döhrmann
- Department of Pediatrics, Division of Host-Microbe Systems and Therapeutics, UC San Diego, La Jolla, California, United States of America
| | - Jason N. Cole
- Department of Pediatrics, Division of Host-Microbe Systems and Therapeutics, UC San Diego, La Jolla, California, United States of America
- The School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland, Australia
| | - Victor Nizet
- Department of Pediatrics, Division of Host-Microbe Systems and Therapeutics, UC San Diego, La Jolla, California, United States of America
- Skaggs School of Pharmacy and Pharmaceutical Sciences, UC San Diego, La Jolla, California, United States of America
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Higashi DL, Biais N, Donahue DL, Mayfield JA, Tessier CR, Rodriguez K, Ashfeld BL, Luchetti J, Ploplis VA, Castellino FJ, Lee SW. Activation of band 3 mediates group A Streptococcus streptolysin S-based beta-haemolysis. Nat Microbiol 2016; 1:15004. [PMID: 27571972 DOI: 10.1038/nmicrobiol.2015.4] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 09/18/2015] [Indexed: 11/09/2022]
Abstract
Streptococcus pyogenes, or group A Streptococcus (GAS), is a human bacterial pathogen that can manifest as a range of diseases from pharyngitis and impetigo to severe outcomes such as necrotizing fasciitis and toxic shock syndrome. GAS disease remains a global health burden with cases estimated at over 700 million annually and over half a million deaths due to severe infections(1). For over 100 years, a clinical hallmark of diagnosis has been the appearance of complete (beta) haemolysis when grown in the presence of blood. This activity is due to the production of a small peptide toxin by GAS known as streptolysin S. Although it has been widely held that streptolysin S exerts its lytic activity through membrane disruption, its exact mode of action has remained unknown. Here, we show, using high-resolution live cell imaging, that streptolysin S induces a dramatic osmotic change in red blood cells, leading to cell lysis. This osmotic change was characterized by the rapid influx of Cl(-) ions into the red blood cells through SLS-mediated disruption of the major erythrocyte anion exchange protein, band 3. Chemical inhibition of band 3 function significantly reduced the haemolytic activity of streptolysin S, and dramatically reduced the pathology in an in vivo skin model of GAS infection. These results provide key insights into the mechanism of streptolysin S-mediated haemolysis and have implications for the development of treatments against GAS.
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Affiliation(s)
- Dustin L Higashi
- Department of Biological Sciences, University of Notre Dame, 100 Galvin Life Sciences Center, Notre Dame, Indiana 46556, USA
| | - Nicolas Biais
- Biology Department, Brooklyn College CUNY, New York 11210, USA
| | - Deborah L Donahue
- W.M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, Indiana 46556, USA
| | - Jeffrey A Mayfield
- W.M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, Indiana 46556, USA
| | - Charles R Tessier
- Indiana University School of Medicine, South Bend, Indiana 46617, USA
| | - Kevin Rodriguez
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Brandon L Ashfeld
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Jeffrey Luchetti
- Department of Biological Sciences, University of Notre Dame, 100 Galvin Life Sciences Center, Notre Dame, Indiana 46556, USA
| | - Victoria A Ploplis
- W.M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, Indiana 46556, USA.,Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Francis J Castellino
- W.M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, Indiana 46556, USA.,Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Shaun W Lee
- Department of Biological Sciences, University of Notre Dame, 100 Galvin Life Sciences Center, Notre Dame, Indiana 46556, USA.,W.M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, Indiana 46556, USA
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Pence MA, Haste NM, Meharena HS, Olson J, Gallo RL, Nizet V, Kristian SA. Beta-Lactamase Repressor BlaI Modulates Staphylococcus aureus Cathelicidin Antimicrobial Peptide Resistance and Virulence. PLoS One 2015; 10:e0136605. [PMID: 26305782 PMCID: PMC4549145 DOI: 10.1371/journal.pone.0136605] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Accepted: 08/06/2015] [Indexed: 02/07/2023] Open
Abstract
BlaI is a repressor of BlaZ, the beta-lactamase responsible for penicillin resistance in Staphylococcus aureus. Through screening a transposon library in S. aureus Newman for susceptibility to cathelicidin antimicrobial peptide, we discovered BlaI as a novel cathelicidin resistance factor. Additionally, through integrational mutagenesis in S. aureus Newman and MRSA Sanger 252 strains, we confirmed the role of BlaI in resistance to human and murine cathelidicin and showed that it contributes to virulence in human whole blood and murine infection models. We further demonstrated that BlaI could be a target for innate immune-based antimicrobial therapies; by removing BlaI through subinhibitory concentrations of 6-aminopenicillanic acid, we were able to sensitize S. aureus to LL-37 killing.
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Affiliation(s)
- Morgan A. Pence
- Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, CA, United States of America
- Department of Pediatrics, School of Medicine, University of California San Diego, La Jolla, CA, United States of America
| | - Nina M. Haste
- Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, CA, United States of America
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, United States of America
| | - Hiruy S. Meharena
- Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, CA, United States of America
| | - Joshua Olson
- Department of Pediatrics, School of Medicine, University of California San Diego, La Jolla, CA, United States of America
| | - Richard L. Gallo
- Department of Dermatology, School of Medicine, University of California San Diego, La Jolla, CA, United States of America
- VA San Diego Healthcare System, San Diego, CA, United States of America
| | - Victor Nizet
- Department of Pediatrics, School of Medicine, University of California San Diego, La Jolla, CA, United States of America
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, United States of America
- * E-mail: (VN); (SAK)
| | - Sascha A. Kristian
- Department of Pediatrics, School of Medicine, University of California San Diego, La Jolla, CA, United States of America
- * E-mail: (VN); (SAK)
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Streptolysin S Promotes Programmed Cell Death and Enhances Inflammatory Signaling in Epithelial Keratinocytes during Group A Streptococcus Infection. Infect Immun 2015; 83:4118-33. [PMID: 26238711 DOI: 10.1128/iai.00611-15] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2015] [Accepted: 07/28/2015] [Indexed: 01/09/2023] Open
Abstract
Streptococcus pyogenes, or group A Streptococcus (GAS), is a pathogen that causes a multitude of human diseases from pharyngitis to severe infections such as toxic shock syndrome and necrotizing fasciitis. One of the primary virulence factors produced by GAS is the peptide toxin streptolysin S (SLS). In addition to its well-recognized role as a cytolysin, recent evidence has indicated that SLS may influence host cell signaling pathways at sublytic concentrations during infection. We employed an antibody array-based approach to comprehensively identify global host cell changes in human epithelial keratinocytes in response to the SLS toxin. We identified key SLS-dependent host responses, including the initiation of specific programmed cell death and inflammatory cascades with concomitant downregulation of Akt-mediated cytoprotection. Significant signaling responses identified by our array analysis were confirmed using biochemical and protein identification methods. To further demonstrate that the observed SLS-dependent host signaling changes were mediated primarily by the secreted toxin, we designed a Transwell infection system in which direct bacterial attachment to host cells was prevented, while secreted factors were allowed access to host cells. The results using this approach were consistent with our direct infection studies and reveal that SLS is a bacterial toxin that does not require bacterial attachment to host cells for activity. In light of these findings, we propose that the production of SLS by GAS during skin infection promotes invasive outcomes by triggering programmed cell death and inflammatory cascades in host cells to breach the keratinocyte barrier for dissemination into deeper tissues.
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48
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Sumitomo T. Group A Streptococcus translocates across an epithelial barrier via degradation of intercellular junctions. J Oral Biosci 2015. [DOI: 10.1016/j.job.2015.03.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Molloy EM, Casjens SR, Cox CL, Maxson T, Ethridge NA, Margos G, Fingerle V, Mitchell DA. Identification of the minimal cytolytic unit for streptolysin S and an expansion of the toxin family. BMC Microbiol 2015. [PMID: 26204951 PMCID: PMC4513790 DOI: 10.1186/s12866-015-0464-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Streptolysin S (SLS) is a cytolytic virulence factor produced by the human pathogen Streptococcus pyogenes and other Streptococcus species. Related "SLS-like" toxins have been characterized in select strains of Clostridium and Listeria, with homologous clusters bioinformatically identified in a variety of other species. SLS is a member of the thiazole/oxazole-modified microcin (TOMM) family of natural products. The structure of SLS has yet to be deciphered and many questions remain regarding its structure-activity relationships. RESULTS In this work, we assessed the hemolytic activity of a series of C-terminally truncated SLS peptides expressed in SLS-deficient S. pyogenes. Our data indicate that while the N-terminal poly-heterocyclizable (NPH) region of SLS substantially contributes to its bioactivity, the variable C-terminal region of the toxin is largely dispensable. Through genome mining we identified additional SLS-like clusters in diverse Firmicutes, Spirochaetes and Actinobacteria. Among the Spirochaete clusters, naturally truncated SLS-like precursors were found in the genomes of three Lyme disease-causing Borrelia burgdorferi sensu lato (Bbsl) strains. Although unable to restore hemolysis in SLS-deficient S. pyogenes, a Bbsl SLS-like precursor peptide was converted to a cytolysin using purified SLS biosynthetic enzymes. A PCR-based screen demonstrated that SLS-like clusters are substantially more prevalent in Bbsl than inferred from publicly available genome sequences. CONCLUSIONS The mutagenesis data described herein indicate that the minimal cytolytic unit of SLS encompasses the NPH region of the core peptide. Interestingly, this region is found in all characterized TOMM cytolysins, as well as the novel putative TOMM cytolysins we discovered. We propose that this conserved region represents the defining feature of the SLS-like TOMM family. We demonstrate the cytolytic potential of a Bbsl SLS-like precursor peptide, which has a core region of similar length to the SLS minimal cytolytic unit, when modified with purified SLS biosynthetic enzymes. As such, we speculate that some Borrelia have the potential to produce a TOMM cytolysin, although the biological significance of this finding remains to be determined. In addition to providing new insight into the structure-activity relationships of SLS, this study greatly expands the cytolysin group of TOMMs.
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Affiliation(s)
- Evelyn M Molloy
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
| | - Sherwood R Casjens
- Division of Microbiology and Immunology, Department of Pathology, University of Utah Medical School, Salt Lake City, UT, 84112, USA.
| | - Courtney L Cox
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA. .,Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
| | - Tucker Maxson
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
| | - Nicole A Ethridge
- School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
| | - Gabriele Margos
- Bavarian Health and Food Safety Authority, National Reference Centre for Borrelia, Oberschleissheim, Germany.
| | - Volker Fingerle
- Bavarian Health and Food Safety Authority, National Reference Centre for Borrelia, Oberschleissheim, Germany.
| | - Douglas A Mitchell
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA. .,Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA. .,Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
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Tai HF, Foo HL, Abdul Rahim R, Loh TC, Abdullah MP, Yoshinobu K. Molecular characterisation of new organisation of plnEF and plw loci of bacteriocin genes harbour concomitantly in Lactobacillus plantarum I-UL4. Microb Cell Fact 2015; 14:89. [PMID: 26077560 PMCID: PMC4467070 DOI: 10.1186/s12934-015-0280-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 06/02/2015] [Indexed: 12/05/2022] Open
Abstract
Background Bacteriocin-producing Lactic acid bacteria (LAB) have vast applications in human and animal health, as well as in food industry. The structural, immunity, regulatory, export and modification genes are required for effective bacteriocin biosynthesis. Variations in gene sequence, composition and organisation will affect the antimicrobial spectrum of bacteriocin greatly. Lactobacillus plantarum I-UL4 is a novel multiple bacteriocin producer that harbours both plw and plnEF structural genes simultaneous which has not been reported elsewhere. Therefore, molecular characterisation of bacteriocin genes that harboured in L. plantarum I-UL4 was conducted in this study. Results and discussion Under optimised conditions, 8 genes (brnQ1, napA1, plnL, plnD, plnEF, plnI, plnG and plnH) of plnEF locus and 2 genes (plw and plwG) of plw locus were amplified successfully from genomic DNA extracted from L. plantarum I-UL4 using specific primers designed from 24 pln genes selected randomly from reported plw, plS, pln423 and plnEF loci. DNA sequence analysis of the flanking region of the amplified genes revealed the presence of two pln loci, UL4-plw and UL4-plnEF loci, which were chromosomally encoded as shown by Southern hybridisation. UL4-plw locus that contained three ORFs were arranged in one operon and possessed remarkable amino acid sequence of LMG2379-plw locus, suggesting it was highly conserved. Interestingly, the UL4-plnEF locus appeared to be a composite pln locus of JDM1-plnEF and J51-plnEF locus in terms of genetic composition and organisation, whereby twenty complete and one partial open reading frames (ORFs) were aligned and organised successfully into five operons. Furthermore, a mutation was detected in plnF structural gene which has contributed to a longer bacteriocin peptide. Conclusions Plantaricin EF and plantaricin W encoded by plnEF and plnW loci are classified as class I bacteriocin and class II bacteriocin molecules respectively. The concurrent presence of two pln loci encoding bacteriocins from two different classes has contributed greatly to the broad inhibitory spectrum of L. plantarum I-UL4. The new genetic composition and organisation of plnEF locus and concurrent presence of plnEF and plnW loci indicated that L. plantarum I-UL4 is a novel multiple bacteriocin producer that possesses vast potentials in various industries.
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Affiliation(s)
- Hui Fong Tai
- Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
| | - Hooi Ling Foo
- Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia. .,Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
| | - Raha Abdul Rahim
- Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia. .,Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
| | - Teck Chewn Loh
- Department of Animal Science, Faculty of Agriculture, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia. .,Institute of Tropical Agriculture, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
| | - Mohd Puad Abdullah
- Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia. .,Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia. .,Institute of Tropical Agriculture, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
| | - Kimura Yoshinobu
- Department of Biofunctional Chemistry, Graduate School of Environmental and Life Sciemce, Okayama University, Okayama, Japan.
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