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Bhardwaj RG, Khalaf ME, Karched M. Secretome analysis and virulence assessment in Abiotrophia defectiva. J Oral Microbiol 2024; 16:2307067. [PMID: 38352067 PMCID: PMC10863525 DOI: 10.1080/20002297.2024.2307067] [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: 08/13/2023] [Accepted: 01/11/2024] [Indexed: 02/16/2024] Open
Abstract
Background Abiotrophia defectiva, although infrequently occurring, is a notable cause of culture-negative infective endocarditis with limited research on its virulence. Associated with oral infections such as dental caries, exploring its secretome may provide insights into virulence mechanisms. Our study aimed to analyze and characterize the secretome of A. defectiva strain CCUG 27639. Methods Secretome of A. defectiva was prepared from broth cultures and subjected to mass spectrometry and proteomics for protein identification. Inflammatory potential of the secretome was assessed by ELISA. Results Eighty-four proteins were identified, with diverse subcellular localizations predicted by PSORTb. Notably, 20 were cytoplasmic, 12 cytoplasmic membrane, 5 extracellular, and 9 cell wall-anchored proteins. Bioinformatics tools revealed 54 proteins secreted via the 'Sec' pathway and 8 via a non-classical pathway. Moonlighting functions were found in 23 proteins, with over 20 exhibiting potential virulence properties, including peroxiredoxin and oligopeptide ABC transporter substrate-binding protein. Gene Ontology and KEGG analyses categorized protein sequences in various pathways. STRING analysis revealed functional protein association networks. Cytokine profiling demonstrated significant proinflammatory cytokine release (IL-8, IL-1β, and CCL5) from human PBMCs. Conclusions Our study provides a comprehensive understanding of A. defectiva's secretome, laying the foundation for insights into its pathogenicity.
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Affiliation(s)
- Radhika G Bhardwaj
- Oral Microbiology Research Laboratory, Department of Bioclinical Sciences College of Dentistry, Kuwait University, Safat, Kuwait
| | - Mai E Khalaf
- Department of General Dental Practice, College of Dentistry, Kuwait University, Safat, Kuwait
| | - Maribasappa Karched
- Oral Microbiology Research Laboratory, Department of Bioclinical Sciences College of Dentistry, Kuwait University, Safat, Kuwait
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Pavkova I, Kopeckova M, Link M, Vlcak E, Filimonenko V, Lecova L, Zakova J, Laskova P, Sheshko V, Machacek M, Stulik J. Francisella tularensis Glyceraldehyde-3-Phosphate Dehydrogenase Is Relocalized during Intracellular Infection and Reveals Effect on Cytokine Gene Expression and Signaling. Cells 2023; 12:cells12040607. [PMID: 36831274 PMCID: PMC9954481 DOI: 10.3390/cells12040607] [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: 12/12/2022] [Revised: 01/26/2023] [Accepted: 02/08/2023] [Indexed: 02/17/2023] Open
Abstract
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is known for its multifunctionality in several pathogenic bacteria. Our previously reported data suggest that the GAPDH homologue of Francisella tularensis, GapA, might also be involved in other processes beyond metabolism. In the present study, we explored GapA's potential implication in pathogenic processes at the host cell level. Using immunoelectron microscopy, we demonstrated the localization of this bacterial protein inside infected macrophages and its peripheral distribution in bacterial cells increasing with infection time. A quantitative proteomic approach based on stable isotope labeling of amino acids in cell culture (SILAC) combined with pull-down assay enabled the identification of several of GapA's potential interacting partners within the host cell proteome. Two of these partners were further confirmed by alternative methods. We also investigated the impact of gapA deletion on the transcription of selected cytokine genes and the activation of the main signaling pathways. Our results show that ∆gapA-induced transcription of genes encoding several cytokines whose expressions were not affected in cells infected with a fully virulent wild-type strain. That might be caused, at least in part, by the detected differences in ERK/MAPK signaling activation. The experimental observations together demonstrate that the F. tularensis GAPDH homologue is directly implicated in multiple host cellular processes and, thereby, that it participates in several molecular mechanisms of pathogenesis.
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Affiliation(s)
- Ivona Pavkova
- Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence, Trebesska 1575, 500 01 Hradec Kralove, Czech Republic
- Correspondence: ; Tel.: +420-973-255-201
| | - Monika Kopeckova
- Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence, Trebesska 1575, 500 01 Hradec Kralove, Czech Republic
| | - Marek Link
- Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence, Trebesska 1575, 500 01 Hradec Kralove, Czech Republic
| | - Erik Vlcak
- Institute of Molecular Genetics of the Czech Academy of Sciences, Electron Microscopy Core Facility, Videnska 1083, 142 20 Prague, Czech Republic
| | - Vlada Filimonenko
- Institute of Molecular Genetics of the Czech Academy of Sciences, Electron Microscopy Core Facility, Videnska 1083, 142 20 Prague, Czech Republic
- Institute of Molecular Genetics of the Czech Academy of Sciences, Department of Biology of the Cell Nucleus, Videnska 1083, 142 20 Prague, Czech Republic
| | - Lenka Lecova
- Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence, Trebesska 1575, 500 01 Hradec Kralove, Czech Republic
| | - Jitka Zakova
- Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence, Trebesska 1575, 500 01 Hradec Kralove, Czech Republic
| | - Pavlina Laskova
- Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence, Trebesska 1575, 500 01 Hradec Kralove, Czech Republic
| | - Valeria Sheshko
- Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence, Trebesska 1575, 500 01 Hradec Kralove, Czech Republic
| | - Miloslav Machacek
- Department of Biochemical Sciences, Faculty of Pharmacy in Hradec Kralove, Charles University in Prague, Akademika Heyrovskeho 1203, 500 05 Hradec Kralove, Czech Republic
| | - Jiri Stulik
- Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence, Trebesska 1575, 500 01 Hradec Kralove, Czech Republic
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3
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Purohit G, Mishra B, Sahoo S, Mahapatra A. Granulicatella adiacens as an Unusual Cause of Empyema: A Case Report and Review of Literature. J Lab Physicians 2022; 14:343-347. [PMID: 36119420 PMCID: PMC9473932 DOI: 10.1055/s-0042-1744236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Granulicatella adiacens
, a nutritionally variant
Streptococcus
(NVS), is part of the normal commensal flora of human mouth, genital, and intestinal tracts and rarely causes disease. It has been mostly reported from bacteremia and endocarditis cases, but rarely can cause vertebral osteomyelitis, pancreatic abscess, otitis media, and endovascular, central nervous system, ocular, oral, bone and joint, and genitourinary infections. Due to requirement of fastidious culture conditions and non-specific colony morphology, serious diagnostic difficulties may arise in cases of NVS infections. Here, we are reporting a rare fatal infection of
G. adiacens
presented with empyema complicated to sepsis and necrotizing fasciitis.
Clinicians should be aware of the pathogenic potential of
Granulicatella adiacens
(a normal commensal flora of human mouth, genital and intestinal tracts). Appropriate supplemented media and a reliable detection system should be used to identify these fastidious organisms. We present this rare case to bring awareness among clinicians regarding such a rare but potentially fatal infection.
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Affiliation(s)
- Geetarani Purohit
- Department of Microbiology, All India Institute of Medical Sciences, Bhubaneswar, India
- Department of Microbiology and Infection Control, Vikash Multispeciality Hospital, Bargarh, Odisha, India
| | - Baijayantimala Mishra
- Department of Microbiology, All India Institute of Medical Sciences, Bhubaneswar, India
| | - Satyajeet Sahoo
- Department of Pulmonary Medicine, All India Institute of Medical Sciences, Bhubaneswar, India
| | - Ashoka Mahapatra
- Department of Microbiology, All India Institute of Medical Sciences, Bhubaneswar, India
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Sheshko V, Link M, Golovliov I, Balonova L, Stulik J. Utilization of a tetracycline-inducible system for high-level expression of recombinant proteins in Francisella tularensis LVS. Plasmid 2021; 115:102564. [PMID: 33610608 DOI: 10.1016/j.plasmid.2021.102564] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 01/14/2021] [Accepted: 01/27/2021] [Indexed: 12/28/2022]
Abstract
Francisella tularensis is a Gram-negative intracellular pathogen causing tularemia. A number of its potential virulence factors have been identified, but their biology and functions are not precisely known. Understanding the biological and immunological functions of these proteins requires adequate genetic tools for homologous and heterologous expression of cloned genes, maintaining both original structure and post-translational modifications. Here, we report the construction of a new multipurpose shuttle plasmid - pEVbr - which can be used for high-level expression in F. tularensis. The pEVbr plasmid has been constructed by modifying the TetR-regulated expression vector pEDL17 (LoVullo, 2012) that includes (i) a strong F. tularensis bfr promoter, and (ii) two tet operator sequences cloned into the promoter. The cloned green fluorescent protein (GFP), used as a reporter, demonstrated almost undetectable basal expression level under uninduced conditions and a highly dynamic dose-dependent response to the inducer. The utility of the system was further confirmed by cloning the gapA and FTT_1676 genes into the pEVbr vector and quantifying proteins expression in F. tularensis LVS, as well as by studying post-translational modification of the cloned genes. This study demonstrates that high levels of recombinant native-like Francisella proteins can be produced in Francisella cells. Hence, this system may be beneficial for the analysis of protein function and the development of new treatments and vaccines.
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Affiliation(s)
- Valeria Sheshko
- Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czech Republic.
| | - Marek Link
- Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czech Republic
| | - Igor Golovliov
- Department of Clinical Microbiology, Umeå University, SE-901 85 Umeå, Sweden
| | - Lucie Balonova
- Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czech Republic
| | - Jiri Stulik
- Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czech Republic
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Kopeckova M, Pavkova I, Link M, Rehulka P, Stulik J. Identification of Bacterial Protein Interaction Partners Points to New Intracellular Functions of Francisella tularensis Glyceraldehyde-3-Phosphate Dehydrogenase. Front Microbiol 2020; 11:576618. [PMID: 33013814 PMCID: PMC7513575 DOI: 10.3389/fmicb.2020.576618] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 08/19/2020] [Indexed: 11/13/2022] Open
Abstract
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is well known for its involvement in numerous non-metabolic processes inside mammalian cells. Alternative functions of prokaryotic GAPDH are mainly deduced from its extracellular localization ability to bind to selected host proteins. Data on its participation in intracellular bacterial processes are scarce as there has been to date only one study dealing with this issue. We previously have reported several points of evidence that the GAPDH homolog of Francisella tularensis GapA might also exert additional non-enzymatic functions. Following on from our earlier observations we decided to identify GapA's interacting partners within the bacterial proteome to explore its new roles at intracellular level. The quantitative proteomics approach based on stable isotope labeling of amino acids in cell culture (SILAC) in combination with affinity purification mass spectrometry enabled us to identify 18 proteins potentially interacting with GapA. Six of those interactions were further confirmed by alternative methods. Half of the identified proteins were involved in non-metabolic processes. Further analysis together with quantitative label-free comparative analysis of proteomes isolated from the wild-type strain strain with deleted gapA gene suggests that GapA is implicated in DNA repair processes. Absence of GapA promotes secretion of its most potent interaction partner the hypothetical protein with peptidase propeptide domain (PepSY) thereby indicating that it impacts on subcellular distribution of some proteins.
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Affiliation(s)
- Monika Kopeckova
- Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czechia
| | - Ivona Pavkova
- Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czechia
| | - Marek Link
- Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czechia
| | - Pavel Rehulka
- Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czechia
| | - Jiri Stulik
- Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czechia
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Kopeckova M, Pavkova I, Stulik J. Diverse Localization and Protein Binding Abilities of Glyceraldehyde-3-Phosphate Dehydrogenase in Pathogenic Bacteria: The Key to its Multifunctionality? Front Cell Infect Microbiol 2020; 10:89. [PMID: 32195198 PMCID: PMC7062713 DOI: 10.3389/fcimb.2020.00089] [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: 12/13/2019] [Accepted: 02/19/2020] [Indexed: 12/12/2022] Open
Abstract
Bacterial proteins exhibiting two or more unrelated functions, referred to as moonlighting proteins, are suggested to contribute to full virulence manifestation in pathogens. An expanding number of published studies have revealed the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) to be a multitasking protein with virulence impact in a number of pathogenic bacteria. This protein can be detected on the bacterial surface or outside the bacterial cell, where it interacts with host proteins. In this way, GAPDH is able to modulate various pathogenic processes. Moreover, it has been shown to be involved in non-enzymatic processes inside the bacterial cell. In this mini review, we summarize main findings concerning the multiple localization and protein interactions of GAPDH derived from bacterial pathogens of humans. We also briefly discuss problems associated with using GAPDH as a vaccine antigen and endeavor to inspire further research to fill gaps in the existing knowledge.
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Affiliation(s)
- Monika Kopeckova
- Department of Molecular Pathology and Biology, Faculty of Military Health Science, University of Defence, Hradec Kralove, Czechia
| | - Ivona Pavkova
- Department of Molecular Pathology and Biology, Faculty of Military Health Science, University of Defence, Hradec Kralove, Czechia
| | - Jiri Stulik
- Department of Molecular Pathology and Biology, Faculty of Military Health Science, University of Defence, Hradec Kralove, Czechia
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The D-alanyl-d-alanine carboxypeptidase enzyme is essential for virulence in the Schu S4 strain of Francisella tularensis and a dacD mutant is able to provide protection against a pneumonic challenge. Microb Pathog 2019; 137:103742. [PMID: 31513897 DOI: 10.1016/j.micpath.2019.103742] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 07/22/2019] [Accepted: 09/09/2019] [Indexed: 01/04/2023]
Abstract
Low molecular mass penicillin binding proteins (LMM PBP) are bacterial enzymes involved in the final steps of peptidoglycan biosynthesis. In Escherichia coli, most LMM PBP exhibit dd-carboxypeptidase activity, are not essential for growth in routine laboratory media, and contributions to virulent phenotypes remain largely unknown. The Francisella tularensis Schu S4 genome harbors the dacD gene (FTT_1029), which encodes a LMM PBP with homology to PBP6b of E. coli. Disruption of this locus in the fully virulent Schu S4 strain resulted in a mutant that could not grow in Chamberlain's Defined Medium and exhibited severe morphological defects. Further characterization studies demonstrated that the growth defects of the dacD mutant were pH-dependent, and could be partially restored by growth at neutral pH or fully restored by genetic complementation. Infection of murine macrophage-like cells showed that the Schu S4 dacD mutant is capable of intracellular replication. However, this mutant was attenuated in BALB/c mice following intranasal challenge (LD50 = 603 CFU) as compared to mice challenged with the parent (LD50 = 1 CFU) or complemented strain (LD50 = 1 CFU). Additionally, mice that survived infection with the dacD mutant showed significant protection against subsequent challenge with the parent strain. Collectively, these results indicate that the DacD protein of F. tularensis is essential for growth in low pH environments and virulence in vivo. These results also suggest that a PBP mutant could serve as the basis of a novel, live attenuated vaccine strain.
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8
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Karched M, Bhardwaj RG, Tiss A, Asikainen S. Proteomic Analysis and Virulence Assessment of Granulicatella adiacens Secretome. Front Cell Infect Microbiol 2019; 9:104. [PMID: 31069174 PMCID: PMC6491454 DOI: 10.3389/fcimb.2019.00104] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 03/26/2019] [Indexed: 12/31/2022] Open
Abstract
Despite reports on the occurrence of Granulicatella adiacens in infective endocarditis, few mechanistic studies on its virulence characteristics or pathogenicity are available. Proteins secreted by this species may act as determinants of host-microbe interaction and play a role in virulence. Our aim in this study was to investigate and functionally characterize the secretome of G. adiacens. Proteins in the secretome preparation were digested by trypsin and applied to nanoLC-ESI-MS/MS. By using a combined mass spectrometry and bioinformatics approach, we identified 101 proteins. Bioinformatics tools predicting subcellular localization revealed that 18 of the secreted proteins possessed signal sequence. More than 20% of the secretome proteins were putative virulence proteins including serine protease, superoxide dismutase, aminopeptidase, molecular chaperone DnaK, and thioredoxin. Ribosomal proteins, molecular chaperones, and glycolytic enzymes, together known as "moonlighting proteins," comprised fifth of the secretome proteins. By Gene Ontology analysis, more than 60 proteins of the secretome were grouped in biological processes or molecular functions. KEGG pathway analysis disclosed that the secretome consisted of enzymes involved in biosynthesis of antibiotics. Cytokine profiling revealed that secreted proteins stimulated key cytokines, such as IL-1β, MCP-1, TNF-α, and RANTES from human PBMCs. In summary, the results from the current investigation of the G. adiacens secretome provide a basis for understanding possible pathogenic mechanisms of G. adiacens.
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Affiliation(s)
- Maribasappa Karched
- Oral Microbiology Research Laboratory, Faculty of Dentistry, Kuwait University, Kuwait City, Kuwait
| | - Radhika G Bhardwaj
- Oral Microbiology Research Laboratory, Faculty of Dentistry, Kuwait University, Kuwait City, Kuwait
| | - Ali Tiss
- Functional Proteomics and Metabolomics Unit, Dasman Diabetes Institute, Kuwait City, Kuwait
| | - Sirkka Asikainen
- Oral Microbiology Research Laboratory, Faculty of Dentistry, Kuwait University, Kuwait City, Kuwait
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Best A, Abu Kwaik Y. Nutrition and Bipartite Metabolism of Intracellular Pathogens. Trends Microbiol 2019; 27:550-561. [PMID: 30655036 DOI: 10.1016/j.tim.2018.12.012] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 11/20/2018] [Accepted: 12/20/2018] [Indexed: 12/29/2022]
Abstract
The host is a nutrient-rich niche for microbial pathogens, but one that comes with obstacles and challenges. Many intracellular pathogens like Legionella pneumophila, Coxiella burnetii, Listeria monocytogenes, and Chlamydia trachomatis have developed bipartite metabolism within their hosts. This style of metabolic regulation enables pathogen sensing of specific nutrients to engage them into catabolic and anabolic processes, and contributes to temporal and spatial pathogen phenotypic modulation. Not only have intracellular pathogens adapted their metabolism to the host, they have also acquired idiosyncratic strategies to exploit host nutritional supplies and intercept metabolites. Francisella tularensis and Anaplasma phagocytophilum alter host autophagy, Shigella flexneri intercepts all host pyruvate, while L. pneumophila induces host protein degradation and blocks protein translation. Strategies of pathogen manipulation of host nutrients could serve as therapeutic targets.
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Affiliation(s)
- Ashley Best
- Department of Microbiology and Immunology, College of Medicine, University of Louisville, KY, USA
| | - Yousef Abu Kwaik
- Department of Microbiology and Immunology, College of Medicine, University of Louisville, KY, USA; Center for Predictive Medicine, College of Medicine, University of Louisville, KY, USA.
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Organization of multi-binding to host proteins: The glyceraldehyde-3-phosphate dehydrogenase (GAPDH) of Mycoplasma pneumoniae. Microbiol Res 2019; 218:22-31. [DOI: 10.1016/j.micres.2018.09.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 08/29/2018] [Accepted: 09/21/2018] [Indexed: 12/28/2022]
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Spidlova P, Stojkova P, Dankova V, Senitkova I, Santic M, Pinkas D, Philimonenko V, Stulik J. Francisella tularensis D-Ala D-Ala Carboxypeptidase DacD Is Involved in Intracellular Replication and It Is Necessary for Bacterial Cell Wall Integrity. Front Cell Infect Microbiol 2018; 8:111. [PMID: 29692981 PMCID: PMC5903032 DOI: 10.3389/fcimb.2018.00111] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 03/21/2018] [Indexed: 12/16/2022] Open
Abstract
D-alanyl-D-alanine carboxypeptidase, product of dacD gene in Francisella, belongs to penicillin binding proteins (PBPs) and is involved in remodeling of newly synthetized peptidoglycan. In E. coli, PBPs are synthetized in various growth phases and they are able to substitute each other to a certain extent. The DacD protein was found to be accumulated in fraction enriched in membrane proteins from severely attenuated dsbA deletion mutant strain. It has been presumed that the DsbA is not a virulence factor by itself but that its substrates, whose correct folding and topology are dependent on the DsbA oxidoreductase and/or isomerase activities, are the primary virulence factors. Here we demonstrate that Francisella DacD is required for intracellular replication and virulence in mice. The dacD insertion mutant strain showed higher sensitivity to acidic pH, high temperature and high osmolarity when compared to the wild-type. Eventually, transmission electron microscopy revealed differences in mutant bacteria in both the size and defects in outer membrane underlying its SDS and serum sensitivity. Taken together these results suggest DacD plays an important role in Francisella pathogenicity.
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Affiliation(s)
- Petra Spidlova
- Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czechia
| | - Pavla Stojkova
- Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czechia
| | - Vera Dankova
- Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czechia
| | - Iva Senitkova
- Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czechia
| | - Marina Santic
- Department of Microbiology and Parasitology, Medical Faculty, University of Rijeka, Rijeka, Croatia
| | - Dominik Pinkas
- Microscopy Center, Institute of Molecular Genetics ASCR v.v.i., Electron Microscopy Core Facility, Prague, Czechia
| | - Vlada Philimonenko
- Microscopy Center, Institute of Molecular Genetics ASCR v.v.i., Electron Microscopy Core Facility, Prague, Czechia
- Department of Biology of the Cell Nucleus, Institute of Molecular Genetics ASCR v.v.i., Prague, Czechia
| | - Jiri Stulik
- Department of Molecular Pathology and Biology, Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czechia
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