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Airborne Prokaryotic, Fungal and Eukaryotic Communities of an Urban Environment in the UK. ATMOSPHERE 2022. [DOI: 10.3390/atmos13081212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Bioaerosols often contain human pathogens and allergens affecting public health. However, relatively little attention has been given to bioaerosols compared with non-biological aerosols. In this study, we aimed to identify bioaerosol compositions in Manchester, UK by applying high throughput sequencing methods and to find potential sources. Samples were collected at Manchester Air Quality Super Site at the Firs Environmental Research Station in November 2019 and in February 2020. Total DNA has been extracted and sequenced targeting the 16S rRNA gene of prokaryotes, ITS region of fungal DNA and 18S rRNA gene of eukaryotes. We found marine environment-associated bacteria and archaea were relatively more abundant in the February 2020 samples compared with the November 2019 samples, consistent with the North West marine origin based on wind back-trajectory analysis. In contrast, an OTU belonging to Methylobacterium, which includes many species resistant to heavy metals, was relatively more abundant in November 2019 when there were higher metal concentrations. Fungal taxa that fruit all year were relatively more abundant in the February 2020 samples while autumn fruiting species generally had higher relative abundance in the November 2019 samples. There were higher relative abundances of land plants and algae in the February 2020 samples based on 18S rRNA gene sequencing. One of the OTUs belonging to the coniferous yew genus Taxus was more abundant in the February 2020 samples agreeing with the usual pollen season of yews in the UK which is from mid-January until late April. The result from this study suggests a potential application of bioaerosol profiling for tracing the source of atmospheric particles.
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Systemic Lectin-Glycan Interaction of Pathogenic Enteric Bacteria in the Gastrointestinal Tract. Int J Mol Sci 2022; 23:ijms23031451. [PMID: 35163392 PMCID: PMC8835900 DOI: 10.3390/ijms23031451] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 01/20/2022] [Accepted: 01/25/2022] [Indexed: 01/27/2023] Open
Abstract
Microorganisms, such as bacteria, viruses, and fungi, and host cells, such as plants and animals, have carbohydrate chains and lectins that reciprocally recognize one another. In hosts, the defense system is activated upon non-self-pattern recognition of microbial pathogen-associated molecular patterns. These are present in Gram-negative and Gram-positive bacteria and fungi. Glycan-based PAMPs are bound to a class of lectins that are widely distributed among eukaryotes. The first step of bacterial infection in humans is the adhesion of the pathogen's lectin-like proteins to the outer membrane surfaces of host cells, which are composed of glycans. Microbes and hosts binding to each other specifically is of critical importance. The adhesion factors used between pathogens and hosts remain unknown; therefore, research is needed to identify these factors to prevent intestinal infection or treat it in its early stages. This review aims to present a vision for the prevention and treatment of infectious diseases by identifying the role of the host glycans in the immune response against pathogenic intestinal bacteria through studies on the lectin-glycan interaction.
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Proteins from the core genome of Corynebacterium ulcerans respond for pathogenicity and reveal promising vaccine targets for diphtheria. Microb Pathog 2021; 161:105263. [PMID: 34687839 DOI: 10.1016/j.micpath.2021.105263] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 10/14/2021] [Accepted: 10/19/2021] [Indexed: 11/23/2022]
Abstract
Corynebacterium ulcerans is an emerging pathogen able to transmit the acute infection diphtheria to humans. Although there is a well-established vaccine based on the toxin produced by Corynebacterium diphtheriae, another species of this genus known to cause the disease, there is still no vaccine formulations described for C. ulcerans; this fact contributes to the increase in cases of infection that has been observed. In this study, we want to provide information at the genomic level of this bacterium in order to suggest proteins as possible vaccine targets. We carried out an in silico prospection of vaccine candidates through reverse vaccinology for targets that exhibit antigenic potential against diphtheria. We found important virulence factors, such as adhesion-related ones, that are responsible for pathogen-host interaction after infection, but we did not find the diphtheria toxin, which is the main component of the currently available vaccine. This study provides detailed information about the exoproteome and hypothetical proteins from the core genome of C. ulcerans, suggesting vaccine targets to be further tested in vitro for the development of a new vaccine against diphtheria.
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Chang C, Nguyen MT, Ton-That H. Genetic Manipulation of Corynebacterium diphtheriae and Other Corynebacterium Species. ACTA ACUST UNITED AC 2021; 58:e111. [PMID: 32865881 DOI: 10.1002/cpmc.111] [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] [Indexed: 12/14/2022]
Abstract
This article describes several established approaches for genetic manipulation of Corynebacterium diphtheriae, the causative agent of diphtheria that is known to have provided key evidence for Koch's postulates on the germ theory. First, it includes a detailed gene deletion method that generates nonpolar, in-frame, markerless deletion mutants, utilizing the levansucrase SacB as a counter-selectable marker. Second, it provides a thorough protocol for rescuing deletion mutants using Escherichia coli-Corynebacterium shuttle vectors. Finally, a Tn5 transposon mutagenesis procedure is described. In principle, these protocols can be used for other Corynebacterium species, including Corynebacterium glutamicum and Corynebacterium matruchotii. © 2020 Wiley Periodicals LLC Basic Protocol 1: Gene deletion in Corynebacterium diphtheriae Basic Protocol 2: Complementation of a mutant strain Basic Protocol 3: Tn5 transposon mutagenesis of Corynebacterium diphtheriae.
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Affiliation(s)
- Chungyu Chang
- Division of Oral Biology and Medicine, School of Dentistry, University of California, Los Angeles, California
| | - Minh Tan Nguyen
- Division of Oral Biology and Medicine, School of Dentistry, University of California, Los Angeles, California.,NTT Hi-Tech Institute, Nguyen Tat Thanh University, Ho Chi Minh City, Vietnam
| | - Hung Ton-That
- Division of Oral Biology and Medicine, School of Dentistry, University of California, Los Angeles, California.,Molecular Biology Institute, University of California, Los Angeles, California
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Sortase-assembled pili in Corynebacterium diphtheriae are built using a latch mechanism. Proc Natl Acad Sci U S A 2021; 118:2019649118. [PMID: 33723052 DOI: 10.1073/pnas.2019649118] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Gram-positive bacteria assemble pili (fimbriae) on their surfaces to adhere to host tissues and to promote polymicrobial interactions. These hair-like structures, although very thin (1 to 5 nm), exhibit impressive tensile strengths because their protein components (pilins) are covalently crosslinked together via lysine-isopeptide bonds by pilus-specific sortase enzymes. While atomic structures of isolated pilins have been determined, how they are joined together by sortases and how these interpilin crosslinks stabilize pilus structure are poorly understood. Using a reconstituted pilus assembly system and hybrid structural biology methods, we elucidated the solution structure and dynamics of the crosslinked interface that is repeated to build the prototypical SpaA pilus from Corynebacterium diphtheriae We show that sortase-catalyzed introduction of a K190-T494 isopeptide bond between adjacent SpaA pilins causes them to form a rigid interface in which the LPLTG sorting signal is inserted into a large binding groove. Cellular and quantitative kinetic measurements of the crosslinking reaction shed light onto the mechanism of pilus biogenesis. We propose that the pilus-specific sortase in C. diphtheriae uses a latch mechanism to select K190 on SpaA for crosslinking in which the sorting signal is partially transferred from the enzyme to a binding groove in SpaA in order to facilitate catalysis. This process is facilitated by a conserved loop in SpaA, which after crosslinking forms a stabilizing latch that covers the K190-T494 isopeptide bond. General features of the structure and sortase-catalyzed assembly mechanism of the SpaA pilus are likely conserved in Gram-positive bacteria.
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Ribonuclease J-Mediated mRNA Turnover Modulates Cell Shape, Metabolism and Virulence in Corynebacterium diphtheriae. Microorganisms 2021; 9:microorganisms9020389. [PMID: 33672886 PMCID: PMC7917786 DOI: 10.3390/microorganisms9020389] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 02/08/2021] [Accepted: 02/09/2021] [Indexed: 01/16/2023] Open
Abstract
Controlled RNA degradation is a crucial process in bacterial cell biology for maintaining proper transcriptome homeostasis and adaptation to changing environments. mRNA turnover in many Gram-positive bacteria involves a specialized ribonuclease called RNase J (RnJ). To date, however, nothing is known about this process in the diphtheria-causative pathogen Corynebacterium diphtheriae, nor is known the identity of this ribonuclease in this organism. Here, we report that C. diphtheriae DIP1463 encodes a predicted RnJ homolog, comprised of a conserved N-terminal β-lactamase domain, followed by β-CASP and C-terminal domains. A recombinant protein encompassing the β-lactamase domain alone displays 5'-exoribonuclease activity, which is abolished by alanine-substitution of the conserved catalytic residues His186 and His188. Intriguingly, deletion of DIP1463/rnj in C. diphtheriae reduces bacterial growth and generates cell shape abnormality with markedly augmented cell width. Comparative RNA-seq analysis revealed that RnJ controls a large regulon encoding many factors predicted to be involved in biosynthesis, regulation, transport, and iron acquisition. One upregulated gene in the ∆rnj mutant is ftsH, coding for a membrane protease (FtsH) involved in cell division, whose overexpression in the wild-type strain also caused cell-width augmentation. Critically, the ∆rnj mutant is severely attenuated in virulence in a Caenorhabditis elegans model of infection, while the FtsH-overexpressing and toxin-less strains exhibit full virulence as the wild-type strain. Evidently, RNase J is a key ribonuclease in C. diphtheriae that post-transcriptionally influences the expression of numerous factors vital to corynebacterial cell physiology and virulence. Our findings have significant implications for basic biological processes and mechanisms of corynebacterial pathogenesis.
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Complete genome sequencing and comparative CAZyme analysis of Rhodococcus sp. PAMC28705 and PAMC28707 provide insight into their biotechnological and phytopathogenic potential. Arch Microbiol 2021; 203:1731-1742. [PMID: 33459813 DOI: 10.1007/s00203-020-02177-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 11/27/2020] [Accepted: 12/27/2020] [Indexed: 10/22/2022]
Abstract
Study of carbohydrate-active enzymes (CAZymes) can reveal information about the lifestyle and behavior of an organism. Rhodococcus species is well known for xenobiotic metabolism; however, their carbohydrate utilization ability has been less discussed till date. This study aimed to present the CAZyme analysis of two Rhodococcus strains, PAMC28705 and PAMC28707, isolated from lichens in Antarctica, and compare them with other Rhodococcus, Mycobacterium, and Corynebacterium strains. Genome-wide computational analysis was performed using various tools. Results showed similarities in CAZymes across all the studied genera. All three genera showed potential for significant polysaccharide utilization, including starch, cellulose, and pectin referring their biotechnological potential. Keeping in mind the pathogenic strains listed across all three genera, CAZymes associated to pathogenicity were analyzed too. Cutinase enzyme, which has been associated with phytopathogenicity, was abundant in all the studied organisms. CAZyme gene cluster of Rhodococcus sp. PAMC28705 and Rhodococcus sp. PAMC28707 showed the insertion of cutinase in the cluster, further supporting their possible phytopathogenic properties.
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Ramirez NA, Das A, Ton-That H. New Paradigms of Pilus Assembly Mechanisms in Gram-Positive Actinobacteria. Trends Microbiol 2020; 28:999-1009. [PMID: 32499101 DOI: 10.1016/j.tim.2020.05.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 05/08/2020] [Accepted: 05/14/2020] [Indexed: 02/06/2023]
Abstract
Adhesive pili in Gram-positive bacteria represent a variety of extracellular multiprotein polymers that mediate bacterial colonization of specific host tissues and associated pathogenesis. Pili are assembled in two distinct but coupled steps, an orderly crosslinking of pilin monomers and subsequent anchoring of the polymer to peptidoglycan, catalyzed by two transpeptidase enzymes - the pilus-specific sortase and the housekeeping sortase. Here, we review this biphasic assembly mechanism based on studies of two prototypical models, the heterotrimeric pili in Corynebacterium diphtheriae and the heterodimeric pili in Actinomyces oris, highlighting some newly emerged basic paradigms. The disparate mechanisms of protein ligation mediated by the pilus-specific sortase and the spatial positioning of adhesive pili on the cell surface modulated by the housekeeping sortase are among the notable highlights.
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Affiliation(s)
- Nicholas A Ramirez
- Molecular Biology Institute, University of California, Los Angeles, CA, USA
| | - Asis Das
- Department of Medicine, Neag Comprehensive Cancer Center, University of Connecticut Health Center, Farmington, CT, USA
| | - Hung Ton-That
- Molecular Biology Institute, University of California, Los Angeles, CA, USA; Division of Oral Biology and Medicine, School of Dentistry, University of California, Los Angeles, CA, USA.
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9
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The use of sea water as a homemade remedy for infectious conjunctivitis-any cause for alarm? SCIENTIFIC AFRICAN 2019. [DOI: 10.1016/j.sciaf.2019.e00108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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10
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Brodzik K, Krysztopa-Grzybowska K, Polak M, Lach J, Strapagiel D, Zasada AA. Analysis of the Amino Acid Sequence Variation of the 67-72p Protein and the Structural Pili Proteins of Corynebacterium diphtheriae for their Suitability as Potential Vaccine Antigens. Pol J Microbiol 2019; 68:233-246. [PMID: 31250594 PMCID: PMC7256701 DOI: 10.33073/pjm-2019-025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 03/08/2019] [Accepted: 03/09/2019] [Indexed: 11/05/2022] Open
Abstract
The aim of this study was to identify the potential vaccine antigens in Corynebacterium diphtheriae strains by in silico analysis of the amino acid variation in the 67-72p surface protein that is involved in the colonization and induction of epithelial cell apoptosis in the early stages of infection. The analysis of pili structural proteins involved in bacterial adherence to host cells and related to various types of infections was also performed. A polymerase chain reaction (PCR) was carried out to amplify the genes encoding the 67-72p protein and three pili structural proteins (SpaC, SpaI, SapD) and the products obtained were sequenced. The nucleotide sequences of the particular genes were translated into amino acid sequences, which were then matched among all the tested strains using bioinformatics tools. In the last step, the affinity of the tested proteins to major histocompatibility complex (MHC) classes I and II, and linear B-cell epitopes was analyzed. The variations in the nucleotide sequence of the 67-72p protein and pili structural proteins among C. diphtheriae strains isolated from various infections were noted. A transposition of the insertion sequence within the gene encoding the SpaC pili structural proteins was also detected. In addition, the bioinformatics analyses enabled the identification of epitopes for B-cells and T-cells in the conserved regions of the proteins, thus, demonstrating that these proteins could be used as antigens in the potential vaccine development. The results identified the most conserved regions in all tested proteins that are exposed on the surface of C. diphtheriae cells. The aim of this study was to identify the potential vaccine antigens in Corynebacterium diphtheriae strains by in silico analysis of the amino acid variation in the 67–72p surface protein that is involved in the colonization and induction of epithelial cell apoptosis in the early stages of infection. The analysis of pili structural proteins involved in bacterial adherence to host cells and related to various types of infections was also performed. A polymerase chain reaction (PCR) was carried out to amplify the genes encoding the 67–72p protein and three pili structural proteins (SpaC, SpaI, SapD) and the products obtained were sequenced. The nucleotide sequences of the particular genes were translated into amino acid sequences, which were then matched among all the tested strains using bioinformatics tools. In the last step, the affinity of the tested proteins to major histocompatibility complex (MHC) classes I and II, and linear B-cell epitopes was analyzed. The variations in the nucleotide sequence of the 67–72p protein and pili structural proteins among C. diphtheriae strains isolated from various infections were noted. A transposition of the insertion sequence within the gene encoding the SpaC pili structural proteins was also detected. In addition, the bioinformatics analyses enabled the identification of epitopes for B-cells and T-cells in the conserved regions of the proteins, thus, demonstrating that these proteins could be used as antigens in the potential vaccine development. The results identified the most conserved regions in all tested proteins that are exposed on the surface of C. diphtheriae cells.
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Affiliation(s)
- Klaudia Brodzik
- Department of Sera and Vaccines Evaluation, National Institute of Public Health - National Institute of Hygiene , Warsaw , Poland
| | - Katarzyna Krysztopa-Grzybowska
- Department of Sera and Vaccines Evaluation, National Institute of Public Health - National Institute of Hygiene , Warsaw , Poland
| | - Maciej Polak
- Department of Sera and Vaccines Evaluation, National Institute of Public Health - National Institute of Hygiene , Warsaw , Poland
| | - Jakub Lach
- Biobank Lab, Department of Molecular Biophysics, Faculty of Biology and Environmental Protection, University of Lodz , Lodz , Poland
| | - Dominik Strapagiel
- Biobank Lab, Department of Molecular Biophysics, Faculty of Biology and Environmental Protection, University of Lodz , Lodz , Poland ; BBMRI.pl Consortium, Wroclaw Research Center EIT+ , Wroclaw , Poland
| | - Aleksandra Anna Zasada
- Department of Sera and Vaccines Evaluation, National Institute of Public Health - National Institute of Hygiene , Warsaw , Poland
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Meštrović T, Wilson J, Ljubin-Sternak S, Sviben M, Bedenić B, Barać A, Neuberg M, Drenjančević D, Ribić R, Kozina G. A 'pathogenic needle' in a 'commensal haystack': Genetic virulence signatures of Corynebacterium glucuronolyticum that may drive its infectious propensity for the male urogenital system. Med Hypotheses 2019; 126:38-41. [PMID: 31010496 DOI: 10.1016/j.mehy.2019.03.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 03/09/2019] [Accepted: 03/21/2019] [Indexed: 11/24/2022]
Abstract
The predominance of the genus Corynebacterium in the healthy male urogenital system contributes to the resident microbiome of not only the distal urethra, but potentially the proximal urethra and urinary bladder as well. However, for certain species in this genus, pathogenic potential was described, and the salient representative is Corynebacterium glucuronolyticum (C. glucuronolyticum) implicated in cases of urethritis and prostatitis in men. Nonetheless, some still question whether C. glucuronolyticum can actually be considered pathogenic or rather just a commensal species fortuitously isolated in patients with urogenital symptoms and/or syndromes. Although pathogen/commensal dichotomy is not always clear-cut, we hypothesize that specific genetic markers may expose C. glucuronolyticum as a convincingly pathogenic Corynebacterium. More specifically, characteristic pathogenic gene constellation inherent to this species (most notably the presence of specific sortase/SpaA-type pili gene clusters, but also the augmentative role of type VII secretion system) may significantly facilitate host tissue adhesion, with subsequent suppression/evasion of the immune response and acquisition of vitally important nutrients. Consequently, these genetic markers differentiate C. glucuronolyticum from its commensal counterparts, and give this species a pathogenic facet, which can be even further influenced by the Allee effect. In this paper we also propose a specific methodological approach on how to analyze C. glucuronolyticum epithelial colonization capacity and explore inceptive host cell-pathogen interactions that manipulate host environment and immune responses. This entails moving from approaches based primarily on overall homology of primary sequences towards specific structure-function studies to precisely evaluate all stakeholders involved in pili assemblage, cell adhesion and the expression of other virulence traits. In the era of high precision medicine, the hypothesized roles of C. glucuronolyticum adhesion systems in both virulence and nutrient acquisition may also reveal promising targets for future drug developments.
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Affiliation(s)
- Tomislav Meštrović
- Clinical Microbiology and Parasitology Unit, Polyclinic "Dr. Zora Profozić", Zagreb, Croatia; University Centre Varaždin, University North, Varaždin, Croatia.
| | - Jonas Wilson
- Sint Maarten Medical Center, Cay Hill, Sint Maarten (Dutch Part)
| | - Sunčanica Ljubin-Sternak
- University of Zagreb School of Medicine, Zagreb, Croatia; Clinical Microbiology Department, Teaching Institute of Public Health "Dr Andrija Štampar", Zagreb, Croatia
| | - Mario Sviben
- University of Zagreb School of Medicine, Zagreb, Croatia; Microbiology Service, Croatian National Institute of Public Health, Zagreb, Croatia
| | - Branka Bedenić
- University of Zagreb School of Medicine, Zagreb, Croatia; Department of Clinical and Molecular Microbiology, University Hospital Centre Zagreb, Zagreb, Croatia
| | - Aleksandra Barać
- Clinic for Infectious and Tropical Diseases, Clinical Centre of Serbia, Belgrade, Serbia; Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | | | - Domagoj Drenjančević
- Faculty of Medicine, Josip Juraj Strossmayer University of Osijek, Osijek, Croatia; University Hospital Centre, Osijek, Croatia
| | - Rosana Ribić
- University Centre Varaždin, University North, Varaždin, Croatia
| | - Goran Kozina
- University Centre Varaždin, University North, Varaždin, Croatia
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Wang L, Fu L, Liu Z, Guo H, Wang L, Feng M, He Y, Chen Q, Hu J. Comparative Analysis of Antimicrobial Resistance, Integrons, and Virulence Genes Among Extended-Spectrum β-Lactamase-Positive Laribacter hongkongensis from Edible Frogs and Freshwater Fish. Microb Drug Resist 2019; 25:855-864. [PMID: 30767721 DOI: 10.1089/mdr.2018.0366] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Aquatic animals are now recognized to be major hosts of potentially pathogenic Laribacter hongkongensis. A comparative study was carried out among extended-spectrum β-lactamase (ESBL)-producing L. hongkongensis isolated from frogs (47 isolates) and fish (41 isolates) to examine phenotypic and genotypic antimicrobial resistance profiles, integrons, virulence factors, and genetic relatedness. Isolates from frogs showed a higher incidence of antibiotic resistance compared with those from fish for most of the antimicrobials tested, especially trimethoprim-sulfamethoxazole, tetracycline, ciprofloxacin, levofloxacin, and streptomycin. Multidrug-resistant strains were also found more frequently among frog isolates (5.44 traits on average) than among fish isolates (3.29 traits). In frog isolates, class 1 integrons and the resistance genes sul1, sul2, tetA, tetR, and aac(6')-Ib-cr showed a clearly higher incidence compared with isolates from fish. In contrast, blaTEM-1 was higher in fish isolates than in frog isolates. Correlation analysis showed that sul1, sul2, tetA, and tetR were significantly associated with class 1 integrons in frog isolates. The correlations indicated a potential co-selection risk of bacterial resistance to antibiotics. In addition, the distribution of three virulence-associated determinants for the type IV bundle-forming pili gene (bfpA), ferric aerobactin receptor gene (iucD), and iron-responsive element gene (ireA) was markedly higher in strains isolated from frogs than in those isolated from fish. No obvious genetic relatedness was observed between both populations. The large differences found in the incidence of antibiotic resistance, integrons along with the multiple resistance genes, virulence factors, and genetic fingerprints determined by pulsed-field gel electrophoresis suggest a high degree of antibiotic resistance and pathogenicity potential of ESBL-producing L. hongkongensis from isolates found in frogs.
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Affiliation(s)
- Ling Wang
- 1 Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Leiwen Fu
- 1 Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Zhihua Liu
- 2 Department of Infectious Disease, Nanfang Hospital, Guangzhou, China
| | - Huijie Guo
- 1 Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Li Wang
- 3 Maternal and Child Health Hospital of Longgang, Shenzhen, China
| | - Mei Feng
- 4 Center for Disease Control and Prevention of Shunde, Foshan, China
| | - Yaqing He
- 5 Center for Disease Control and Prevention of Shenzhen, Shenzhen, China
| | - Qing Chen
- 1 Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Jing Hu
- 1 Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China.,6 Department of Nosocomial Infection Administration, Zhujiang Hospital, Southern Medical University, Guangzhou, China
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Weerasekera D, Stengel F, Sticht H, de Mattos Guaraldi AL, Burkovski A, Azevedo Antunes C. The C-terminal coiled-coil domain of Corynebacterium diphtheriae DIP0733 is crucial for interaction with epithelial cells and pathogenicity in invertebrate animal model systems. BMC Microbiol 2018; 18:106. [PMID: 30180805 PMCID: PMC6123952 DOI: 10.1186/s12866-018-1247-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 08/23/2018] [Indexed: 02/06/2023] Open
Abstract
Background Corynebacterium diphtheriae is the etiologic agent of diphtheria and different systemic infections. The bacterium has been classically described as an extracellular pathogen. However, a number of studies revealed its ability to invade epithelial cells, indicating a more complex pathogen-host interaction. The molecular mechanisms controlling and facilitating internalization of C. diphtheriae still remains unclear. Recently, the DIP0733 transmembrane protein was found to play an important role in the interaction with matrix proteins and cell surfaces, nematode colonization, cellular internalization and induction of cell death. Results In this study, we identified a number of short linear motifs and structural elements of DIP0733 with putative importance in virulence, using bioinformatic approaches. A C-terminal coiled-coil region of the protein was considered particularly important, since it was found only in DIP0733 homologs in pathogenic Corynebacterium species but not in non-pathogenic corynebacteria. Infections of epithelial cells and transepithelial resistance assays revealed that bacteria expressing the truncated form of C. diphtheriae DIP0733 and C. glutamicum DIP0733 homolog are less virulent, while the fusion of the coiled-coil sequence to the DIP0733 homolog from C. glutamicum resulted in increased pathogenicity. These results were supported by nematode killing assays and experiments using wax moth larvae as invertebrate model systems. Conclusions Our data indicate that the coil-coiled domain of DIP0733 is crucial for interaction with epithelial cells and pathogenicity in invertebrate animal model systems. Electronic supplementary material The online version of this article (10.1186/s12866-018-1247-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Dulanthi Weerasekera
- Microbiology Division, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Franziska Stengel
- Microbiology Division, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Heinrich Sticht
- Division of Bioinformatics, Institute of Biochemistry, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Ana Luíza de Mattos Guaraldi
- Laboratory of Diphtheria and Corynebacteria of Clinical Relevance-LDCIC, Faculty of Medical Sciences, Rio de Janeiro State University, Rio de Janeiro, Brazil
| | - Andreas Burkovski
- Microbiology Division, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Camila Azevedo Antunes
- Microbiology Division, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany. .,Laboratory of Diphtheria and Corynebacteria of Clinical Relevance-LDCIC, Faculty of Medical Sciences, Rio de Janeiro State University, Rio de Janeiro, Brazil.
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Chang C, Amer BR, Osipiuk J, McConnell SA, Huang IH, Hsieh V, Fu J, Nguyen HH, Muroski J, Flores E, Ogorzalek Loo RR, Loo JA, Putkey JA, Joachimiak A, Das A, Clubb RT, Ton-That H. In vitro reconstitution of sortase-catalyzed pilus polymerization reveals structural elements involved in pilin cross-linking. Proc Natl Acad Sci U S A 2018; 115:E5477-E5486. [PMID: 29844180 PMCID: PMC6004493 DOI: 10.1073/pnas.1800954115] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Covalently cross-linked pilus polymers displayed on the cell surface of Gram-positive bacteria are assembled by class C sortase enzymes. These pilus-specific transpeptidases located on the bacterial membrane catalyze a two-step protein ligation reaction, first cleaving the LPXTG motif of one pilin protomer to form an acyl-enzyme intermediate and then joining the terminal Thr to the nucleophilic Lys residue residing within the pilin motif of another pilin protomer. To date, the determinants of class C enzymes that uniquely enable them to construct pili remain unknown. Here, informed by high-resolution crystal structures of corynebacterial pilus-specific sortase (SrtA) and utilizing a structural variant of the enzyme (SrtA2M), whose catalytic pocket has been unmasked by activating mutations, we successfully reconstituted in vitro polymerization of the cognate major pilin (SpaA). Mass spectrometry, electron microscopy, and biochemical experiments authenticated that SrtA2M synthesizes pilus fibers with correct Lys-Thr isopeptide bonds linking individual pilins via a thioacyl intermediate. Structural modeling of the SpaA-SrtA-SpaA polymerization intermediate depicts SrtA2M sandwiched between the N- and C-terminal domains of SpaA harboring the reactive pilin and LPXTG motifs, respectively. Remarkably, the model uncovered a conserved TP(Y/L)XIN(S/T)H signature sequence following the catalytic Cys, in which the alanine substitutions abrogated cross-linking activity but not cleavage of LPXTG. These insights and our evidence that SrtA2M can terminate pilus polymerization by joining the terminal pilin SpaB to SpaA and catalyze ligation of isolated SpaA domains in vitro provide a facile and versatile platform for protein engineering and bio-conjugation that has major implications for biotechnology.
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Affiliation(s)
- Chungyu Chang
- Department of Microbiology and Molecular Genetics, University of Texas Health Science Center, Houston, TX 77030
| | - Brendan R Amer
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
- University of California, Los Angeles-US Department of Energy Institute of Genomics and Proteomics, University of California, Los Angeles, CA 90095
| | - Jerzy Osipiuk
- Center for Structural Genomics of Infectious Diseases, Argonne National Laboratory, Argonne, IL 60439
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637
| | - Scott A McConnell
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
- University of California, Los Angeles-US Department of Energy Institute of Genomics and Proteomics, University of California, Los Angeles, CA 90095
| | - I-Hsiu Huang
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan
| | - Van Hsieh
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
- University of California, Los Angeles-US Department of Energy Institute of Genomics and Proteomics, University of California, Los Angeles, CA 90095
| | - Janine Fu
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
- University of California, Los Angeles-US Department of Energy Institute of Genomics and Proteomics, University of California, Los Angeles, CA 90095
| | - Hong H Nguyen
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
- University of California, Los Angeles-US Department of Energy Institute of Genomics and Proteomics, University of California, Los Angeles, CA 90095
| | - John Muroski
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
- University of California, Los Angeles-US Department of Energy Institute of Genomics and Proteomics, University of California, Los Angeles, CA 90095
| | - Erika Flores
- Department of Microbiology and Molecular Genetics, University of Texas Health Science Center, Houston, TX 77030
| | - Rachel R Ogorzalek Loo
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
- University of California, Los Angeles-US Department of Energy Institute of Genomics and Proteomics, University of California, Los Angeles, CA 90095
| | - Joseph A Loo
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
- University of California, Los Angeles-US Department of Energy Institute of Genomics and Proteomics, University of California, Los Angeles, CA 90095
| | - John A Putkey
- Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, TX 77030
| | - Andrzej Joachimiak
- Center for Structural Genomics of Infectious Diseases, Argonne National Laboratory, Argonne, IL 60439
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637
| | - Asis Das
- Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, CT 06030
| | - Robert T Clubb
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095;
- University of California, Los Angeles-US Department of Energy Institute of Genomics and Proteomics, University of California, Los Angeles, CA 90095
| | - Hung Ton-That
- Department of Microbiology and Molecular Genetics, University of Texas Health Science Center, Houston, TX 77030;
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15
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Corrêa JI, Stocker A, Trindade SC, Vale V, Brito T, Bastos B, Raynal JT, de Miranda PM, de Alcantara AC, Freire SM, Costa LM, Meyer R. In vivo and in vitro expression of five genes involved in Corynebacterium pseudotuberculosis virulence. AMB Express 2018; 8:89. [PMID: 29846821 PMCID: PMC5976562 DOI: 10.1186/s13568-018-0598-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 04/18/2018] [Indexed: 11/18/2022] Open
Abstract
Caseous lymphadenitis (LC) is a chronic contagious disease caused by Corynebacterium pseudotuberculosis, which mainly affects goats and sheep. Vaccination is an effective but not yet well-established method, partly due to a lack of knowledge surrounding the most effective immunoprotective components. The present study aimed to quantify and compare the in vivo expression of genes pld (phospholipase D), cpp (CP40), nanH (neuraminidase H), sodC (superoxide dismutase C) and spaC (adhesin) using qRT-PCR, with the respective expression in vitro. Caseous material of abscesses removed from five animals was cultured, with colonies suggestive of C. pseudotuberculosis identified. RNA extraction was performed on these samples, as well as on the respective pellets derived from liquid cultures brain heart infusion. After evaluating RNA integrity, complementary DNA was synthesized, followed by the relative quantification each of the genes of interest. Mean mRNA expression of the five genes found in abscesses and in cultures differed significantly, with respective values of: nanH 811.50 ± 198.27 and 359.35 ± 75.45 (p = 0.009); cpp 856.31 ± 385.11 and 154.54 ± 94.34 (p = 0.0039); plD 922.70 ± 450.73 and 212.41 ± 153.10 (p = 0.016); sodC 1,293.53 ± 564.75 and 223.63 ± 145.58 (p = 0.016); spaC 1,157.10 ± 525.13 and 214.26 ± 125.70 (p = 0,016). Expression was observed to be 6–8 times higher in abscesses than in cultures, Indicative that is a genetic expression of the in vitro bacterium exists, yet in vivo has a greater magnitude corroborating to one of these virulence factors in the pathogenesis of LC.
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16
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Beijerink NJ, Bergmann W, Szatmári V. Incomplete endothelialization of an intravascular implant and fatal late-onset bacterial ductal arteritis in a dog with occluded patent ductus arteriosus. J Vet Intern Med 2018. [PMID: 29524349 PMCID: PMC5980296 DOI: 10.1111/jvim.15074] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
An 18‐month‐old male Akita Inu dog developed fever and lameness 8 months after successful transcatheter closure of a patent ductus arteriosus with an Amplatz Canine Duct Occluder (ACDO). Corynebacterium species were cultured from 3 blood samples. Echocardiography showed a vegetative process on the aortic valves. The dog died spontaneously 3 days after development of the initial signs. Necropsy confirmed the presence of bacterial ductal arteritis and myocarditis, and revealed an incomplete endothelialization of the intraductal metal implant. The reason for the lack of (neo)endothelialization of the ACDO remains unknown. We conclude that late‐onset bacterial device‐related ductal arteritis can develop in dogs where the implant is incompletely covered by a protective endothelial layer.
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Affiliation(s)
- Niek Jozef Beijerink
- Department of Clinical Sciences of Companion Animals, Utrecht University, Utrecht, The Netherlands
| | | | - Viktor Szatmári
- Department of Clinical Sciences of Companion Animals, Utrecht University, Utrecht, The Netherlands
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17
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Genomics of Corynebacterium striatum, an emerging multidrug-resistant pathogen of immunocompromised patients. Clin Microbiol Infect 2018; 24:1016.e7-1016.e13. [PMID: 29326010 DOI: 10.1016/j.cmi.2017.12.024] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 12/27/2017] [Accepted: 12/28/2017] [Indexed: 10/18/2022]
Abstract
OBJECTIVES Corynebacterium striatum is an emerging multidrug-resistant (MDR) pathogen of immunocompromised and chronically ill patients. The objective of these studies was to provide a detailed genomic analysis of disease-causing C. striatum and determine the genomic drivers of resistance and resistance-gene transmission. METHODS A multi-institutional and prospective pathogen genomics programme flagged seven MDR C. striatum infections occurring close in time, and specifically in immunocompromised patients with underlying respiratory diseases. Whole genome sequencing was used to identify clonal relationships among strains, genetic causes of antimicrobial resistance, and their mobilization capacity. Matrix-assisted linear desorption/ionization-time-of-flight analyses of sequenced isolates provided curated content to improve rapid clinical identification in subsequent cases. RESULTS Epidemiological and genomic analyses identified a related cluster of three out of seven C. striatum among lung transplant patients who had common procedures and exposures at an outlying institution. Genomic analyses further elucidated drivers of the MDR phenotypes, including resistance genes mobilized by IS3504 and ISCg9a-like insertion sequences. Seven mobilizable resistance genes were localized to a common chromosomal region bounded by unpaired insertion sequences, suggesting that a single recombination event could spread resistance to aminoglycosides, macrolides, lincosamides and tetracyclines to naive strains. CONCLUSION In-depth genomic studies of MDR C. striatum reveal its capacity for clonal spread within and across healthcare institutions and identify novel vectors that can mobilize multiple forms of drug resistance, further complicating efforts to treat infections in immunocompromised populations.
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18
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Rajamani Sekar S, Veeraraghavan B, Anandan S, Devanga Ragupathi N, Sangal L, Joshi S. Strengthening the laboratory diagnosis of pathogenicCorynebacteriumspecies in the Vaccine era. Lett Appl Microbiol 2017; 65:354-365. [DOI: 10.1111/lam.12781] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Revised: 07/06/2017] [Accepted: 07/20/2017] [Indexed: 01/06/2023]
Affiliation(s)
- S.K. Rajamani Sekar
- Department of Clinical Microbiology; Christian Medical College; Vellore India
| | - B. Veeraraghavan
- Department of Clinical Microbiology; Christian Medical College; Vellore India
| | - S. Anandan
- Department of Clinical Microbiology; Christian Medical College; Vellore India
| | | | - L. Sangal
- World Health Organization (WHO) Country Office; New Delhi India
| | - S. Joshi
- World Health Organization (WHO) Country Office; New Delhi India
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19
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Silva WM, Folador EL, Soares SC, Souza GHMF, Santos AV, Sousa CS, Figueiredo H, Miyoshi A, Le Loir Y, Silva A, Azevedo V. Label-free quantitative proteomics of Corynebacterium pseudotuberculosis isolates reveals differences between Biovars ovis and equi strains. BMC Genomics 2017; 18:451. [PMID: 28595597 PMCID: PMC5463331 DOI: 10.1186/s12864-017-3835-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 05/31/2017] [Indexed: 11/24/2022] Open
Affiliation(s)
- Wanderson M Silva
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brasil.,INRA, UMR1253 STLO, 35042, Rennes, France.,Agrocampus Ouest, UMR1253 STLO, 35042, Rennes, France
| | - Edson L Folador
- Centro de Biotecnologia, Universidade Federal da Paraíba, João Pessoa, Paraíba, Brasil
| | - Siomar C Soares
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brasil.,Departmento de Microbiologia, Imunologia e Parasitologia, Instituto de Ciências Biológicas e Naturais, Universidade Federal do Triângulo Mineiro, Uberaba, Minas Gerais, Brasil
| | - Gustavo H M F Souza
- Waters Corporation, Waters Technologies Brazil, MS Applications Laboratory, Alphaville, São Paulo, Brasil
| | - Agenor V Santos
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Pará, Brasil
| | - Cassiana S Sousa
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brasil
| | - Henrique Figueiredo
- Escola de Veterinária, Aquavet, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brasil
| | - Anderson Miyoshi
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brasil
| | - Yves Le Loir
- INRA, UMR1253 STLO, 35042, Rennes, France.,Agrocampus Ouest, UMR1253 STLO, 35042, Rennes, France
| | - Artur Silva
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Pará, Brasil
| | - Vasco Azevedo
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brasil.
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20
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Peixoto RS, Antunes CA, Lourêdo LS, Viana VG, Santos CSD, Fuentes Ribeiro da Silva J, Hirata R, Hacker E, Mattos-Guaraldi AL, Burkovski A. Functional characterization of the collagen-binding protein DIP2093 and its influence on host-pathogen interaction and arthritogenic potential of Corynebacterium diphtheriae. MICROBIOLOGY-SGM 2017; 163:692-701. [PMID: 28535857 DOI: 10.1099/mic.0.000467] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Corynebacterium diphtheriae is typically recognized as the a etiological agent of diphtheria, a toxaemic infection of the respiratory tract; however, both non-toxigenic and toxigenic strains are increasingly isolated from cases of invasive infections. The molecular mechanisms responsible for bacterial colonization and dissemination to host tissues remain only partially understood. In this report, we investigated the role of DIP2093, described as a putative adhesin of the serine-aspartate repeat (Sdr) protein family in host-pathogen interactions of C. diphtheriae wild-type strain NCTC13129. Compared to the parental strain, a DIP2093 mutant RN generated in this study was attenuated in its ability to bind to type I collagen, to adhere to and invade epithelial cells, as well as to survive within macrophages. Furthermore, DIP2093 mutant strain RN had a less detrimental impact on the viability of Caenorhabditis elegans as well as in the clinical severity of arthritis in mice. In conclusion, DIP2093 functions as a microbial surface component recognizing adhesive matrix molecules, and may be included among the factors that contribute to the pathogenicity of C. diphtheriae strains, independently of toxin production.
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Affiliation(s)
- Renata Stavracakis Peixoto
- Professur für Mikrobiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.,Department of Medical Microbiology, Institute of Microbiology, Rio de Janeiro Federal University, (IMPPG/UFRJ), Rio de Janeiro, RJ, Brazil.,Laboratory of Diphtheria and Corynebacteria of Clinical Relevance-LDCIC, Faculty of Medical Sciences, Rio de Janeiro State University - UERJ, Rio de Janeiro, RJ, Brazil
| | - Camila Azevedo Antunes
- Professur für Mikrobiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.,Laboratory of Diphtheria and Corynebacteria of Clinical Relevance-LDCIC, Faculty of Medical Sciences, Rio de Janeiro State University - UERJ, Rio de Janeiro, RJ, Brazil
| | - Liliane Simpson Lourêdo
- Laboratory of Diphtheria and Corynebacteria of Clinical Relevance-LDCIC, Faculty of Medical Sciences, Rio de Janeiro State University - UERJ, Rio de Janeiro, RJ, Brazil.,National Institute for Quality Control in Health (INCQS), Fundação Oswaldo Cruz- FIOCRUZ, Rio de Janeiro, RJ, Brazil
| | - Vanilda Gonçalves Viana
- Laboratory of Diphtheria and Corynebacteria of Clinical Relevance-LDCIC, Faculty of Medical Sciences, Rio de Janeiro State University - UERJ, Rio de Janeiro, RJ, Brazil
| | - Cintia Silva Dos Santos
- Laboratory of Diphtheria and Corynebacteria of Clinical Relevance-LDCIC, Faculty of Medical Sciences, Rio de Janeiro State University - UERJ, Rio de Janeiro, RJ, Brazil
| | - Jemima Fuentes Ribeiro da Silva
- Ultrastructure and Tissue Biology, Department of Histology and Embryology, Roberto Alcântara Gomes Biology Institute - iBRAG - UERJ, Rio de Janeiro, RJ, Brazil
| | - Raphael Hirata
- Laboratory of Diphtheria and Corynebacteria of Clinical Relevance-LDCIC, Faculty of Medical Sciences, Rio de Janeiro State University - UERJ, Rio de Janeiro, RJ, Brazil
| | - Elena Hacker
- Professur für Mikrobiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Ana Luíza Mattos-Guaraldi
- Department of Medical Microbiology, Institute of Microbiology, Rio de Janeiro Federal University, (IMPPG/UFRJ), Rio de Janeiro, RJ, Brazil.,Laboratory of Diphtheria and Corynebacteria of Clinical Relevance-LDCIC, Faculty of Medical Sciences, Rio de Janeiro State University - UERJ, Rio de Janeiro, RJ, Brazil
| | - Andreas Burkovski
- Professur für Mikrobiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
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21
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Viana MVC, Figueiredo H, Ramos R, Guimarães LC, Pereira FL, Dorella FA, Selim SAK, Salaheldean M, Silva A, Wattam AR, Azevedo V. Comparative genomic analysis between Corynebacterium pseudotuberculosis strains isolated from buffalo. PLoS One 2017; 12:e0176347. [PMID: 28445543 PMCID: PMC5406005 DOI: 10.1371/journal.pone.0176347] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 04/10/2017] [Indexed: 12/15/2022] Open
Abstract
Corynebacterium pseudotuberculosis is a Gram-positive, pleomorphic, facultative intracellular pathogen that causes Oedematous Skin Disease (OSD) in buffalo. To better understand the pathogenic mechanisms of OSD, we performed a comparative genomic analysis of 11 strains of C. pseudotuberculosis isolated from different buffalo found to be infected in Egypt during an outbreak that occurred in 2008. Sixteen previously described pathogenicity islands (PiCp) were present in all of the new buffalo strains, but one of them, PiCp12, had an insertion that contained both a corynephage and a diphtheria toxin gene, both of which may play a role in the adaptation of C. pseudotuberculosis to this new host. Synteny analysis showed variations in the site of insertion of the corynephage during the same outbreak. A gene functional comparison showed the presence of a nitrate reductase operon that included genes involved in molybdenum cofactor biosynthesis, which is necessary for a positive nitrate reductase phenotype and is a possible adaptation for intracellular survival. Genomes from the buffalo strains also had fusions in minor pilin genes in the spaA and spaD gene cluster (spaCX and spaYEF), which could suggest either an adaptation to this particular host, or mutation events in the immediate ancestor before this particular epidemic. A phylogenomic analysis confirmed a clear separation between the Ovis and Equi biovars, but also showed what appears to be a clustering by host species within the Equi strains.
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Affiliation(s)
- Marcus Vinicius Canário Viana
- Departament of General Biology, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
- Biocomplexity Institute of Virginia Tech, Virginia Tech, Blacksburg, Virginia, United States of America
| | - Henrique Figueiredo
- AQUACEN, National Reference Laboratory for Aquatic Animal Diseases, Ministry of Fisheries and Aquaculture, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Rommel Ramos
- Center of Genomic and System Biology, Federal University of Pará, Belém, Pará, Brazil
| | - Luis Carlos Guimarães
- Center of Genomic and System Biology, Federal University of Pará, Belém, Pará, Brazil
| | - Felipe Luiz Pereira
- AQUACEN, National Reference Laboratory for Aquatic Animal Diseases, Ministry of Fisheries and Aquaculture, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Fernanda Alves Dorella
- AQUACEN, National Reference Laboratory for Aquatic Animal Diseases, Ministry of Fisheries and Aquaculture, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | | | - Mohammad Salaheldean
- Department of Microbiology, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt
| | - Artur Silva
- Center of Genomic and System Biology, Federal University of Pará, Belém, Pará, Brazil
| | - Alice R. Wattam
- Biocomplexity Institute of Virginia Tech, Virginia Tech, Blacksburg, Virginia, United States of America
| | - Vasco Azevedo
- Departament of General Biology, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
- * E-mail:
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22
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Silva WM, Dorella FA, Soares SC, Souza GHMF, Castro TLP, Seyffert N, Figueiredo H, Miyoshi A, Le Loir Y, Silva A, Azevedo V. A shift in the virulence potential of Corynebacterium pseudotuberculosis biovar ovis after passage in a murine host demonstrated through comparative proteomics. BMC Microbiol 2017; 17:55. [PMID: 28327085 PMCID: PMC5361795 DOI: 10.1186/s12866-017-0925-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Accepted: 01/04/2017] [Indexed: 01/19/2023] Open
Abstract
Background Corynebacterium pseudotuberculosis biovar ovis, a facultative intracellular pathogen, is the etiologic agent of caseous lymphadenitis in small ruminants. During the infection process, C. pseudotuberculosis changes its gene expression to resist different types of stresses and to evade the immune system of the host. However, factors contributing to the infectious process of this pathogen are still poorly documented. To better understand the C. pseudotuberculosis infection process and to identify potential factors which could be involved in its virulence, experimental infection was carried out in a murine model using the strain 1002_ovis and followed by a comparative proteomic analysis of the strain before and after passage. Results The experimental infection assays revealed that strain 1002_ovis exhibits low virulence potential. However, the strain recovered from the spleen of infected mice and used in a new infection challenge showed a dramatic change in its virulence potential. Label-free proteomic analysis of the culture supernatants of strain 1002_ovis before and after passage in mice revealed that 118 proteins were differentially expressed. The proteome exclusive to the recovered strain contained important virulence factors such as CP40 proteinase and phospholipase D exotoxin, the major virulence factor of C. pseudotuberculosis. Also, the proteome from recovered condition revealed different classes of proteins involved in detoxification processes, pathogenesis and export pathways, indicating the presence of distinct mechanisms that could contribute in the infectious process of this pathogen. Conclusions This study shows that C. pseudotuberculosis modifies its proteomic profile in the laboratory versus infection conditions and adapts to the host context during the infection process. The screening proteomic performed us enable identify known virulence factors, as well as potential proteins that could be related to virulence this pathogen. These results enhance our understanding of the factors that might influence in the virulence of C. pseudotuberculosis. Electronic supplementary material The online version of this article (doi:10.1186/s12866-017-0925-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Wanderson M Silva
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.,INRA, UMR1253 STLO, 35042, Rennes, France.,Agrocampus Ouest, UMR1253 STLO, 35042, Rennes, France
| | - Fernanda A Dorella
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Siomar C Soares
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Gustavo H M F Souza
- Waters Corporation, Waters Technologies Brazil, MS Applications Laboratory, Alphaville, São Paulo, Brazil
| | - Thiago L P Castro
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Núbia Seyffert
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Henrique Figueiredo
- Aquacen, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Anderson Miyoshi
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Yves Le Loir
- INRA, UMR1253 STLO, 35042, Rennes, France.,Agrocampus Ouest, UMR1253 STLO, 35042, Rennes, France
| | - Artur Silva
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Guamá, Belém, Pará, Brazil
| | - Vasco Azevedo
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
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23
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Santana-Jorge KTO, Santos TM, Tartaglia NR, Aguiar EL, Souza RFS, Mariutti RB, Eberle RJ, Arni RK, Portela RW, Meyer R, Azevedo V. Putative virulence factors of Corynebacterium pseudotuberculosis FRC41: vaccine potential and protein expression. Microb Cell Fact 2016; 15:83. [PMID: 27184574 PMCID: PMC4869379 DOI: 10.1186/s12934-016-0479-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 05/03/2016] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Corynebacterium pseudotuberculosis, a facultative intracellular bacterial pathogen, is the etiological agent of caseous lymphadenitis (CLA), an infectious disease that affects sheep and goats and it is responsible for significant economic losses. The disease is characterized mainly by bacteria-induced caseous necrosis in lymphatic glands. New vaccines are needed for reliable control and management of CLA. Thus, the putative virulence factors SpaC, SodC, NanH, and PknG from C. pseudotuberculosis FRC41 may represent new target proteins for vaccine development and pathogenicity studies. RESULTS SpaC, PknG and NanH presented better vaccine potential than SodC after in silico analyses. A total of 136 B and T cell epitopes were predicted from the four putative virulence factors. A cluster analysis was performed to evaluate the redundancy degree among the sequences of the predicted epitopes; 57 clusters were formed, most of them (34) were single clusters. Two clusters from PknG and one from SpaC grouped epitopes for B and T-cell (MHC I and II). These epitopes can thus potentially stimulate a complete immune response (humoral and cellular) against C. pseudotuberculosis. Several other clusters, including two from NanH, grouped B-cell epitopes with either MHC I or II epitopes. The four target proteins were expressed in Escherichia coli. A purification protocol was developed for PknG expression. CONCLUSIONS In silico analyses show that the putative virulence factors SpaC, PknG and NanH present good potential for CLA vaccine development. Target proteins were successfully expressed in E. coli. A protocol for PknG purification is described.
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Affiliation(s)
- Karina T. O. Santana-Jorge
- />Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Avenida Antonio Carlos, 6627, Pampulha, Belo Horizonte, 31270-901 Brazil
| | - Túlio M. Santos
- />Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Avenida Antonio Carlos, 6627, Pampulha, Belo Horizonte, 31270-901 Brazil
- />Uniclon Biotecnologia, Belo Horizonte, MG Brazil
| | - Natayme R. Tartaglia
- />Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Avenida Antonio Carlos, 6627, Pampulha, Belo Horizonte, 31270-901 Brazil
| | - Edgar L. Aguiar
- />Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Avenida Antonio Carlos, 6627, Pampulha, Belo Horizonte, 31270-901 Brazil
| | - Renata F. S. Souza
- />Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Avenida Antonio Carlos, 6627, Pampulha, Belo Horizonte, 31270-901 Brazil
| | - Ricardo B. Mariutti
- />Multiuser Center for Biomolecular Innovation, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista “Júlio de Mesquita Filho”, São José Do Rio Preto, SP Brazil
| | - Raphael J. Eberle
- />Multiuser Center for Biomolecular Innovation, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista “Júlio de Mesquita Filho”, São José Do Rio Preto, SP Brazil
| | - Raghuvir K. Arni
- />Multiuser Center for Biomolecular Innovation, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista “Júlio de Mesquita Filho”, São José Do Rio Preto, SP Brazil
| | - Ricardo W. Portela
- />Laboratório de Imunologia e Biologia Molecular, Instituto de Ciências da Saúde, Universidade Federal da Bahia, Salvador, BA Brazil
| | - Roberto Meyer
- />Laboratório de Imunologia e Biologia Molecular, Instituto de Ciências da Saúde, Universidade Federal da Bahia, Salvador, BA Brazil
| | - Vasco Azevedo
- />Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Avenida Antonio Carlos, 6627, Pampulha, Belo Horizonte, 31270-901 Brazil
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Tytgat HLP, van Teijlingen NH, Sullan RMA, Douillard FP, Rasinkangas P, Messing M, Reunanen J, Satokari R, Vanderleyden J, Dufrêne YF, Geijtenbeek TBH, de Vos WM, Lebeer S. Probiotic Gut Microbiota Isolate Interacts with Dendritic Cells via Glycosylated Heterotrimeric Pili. PLoS One 2016; 11:e0151824. [PMID: 26985831 PMCID: PMC4795749 DOI: 10.1371/journal.pone.0151824] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 03/06/2016] [Indexed: 02/06/2023] Open
Abstract
Mapping of the microbial molecules underlying microbiota-host interactions is key to understand how microbiota preserve mucosal homeostasis. A pivotal family of such bacterial molecules are pili. Pili are proteinaceous cell wall appendages with a well-documented role in adhesion, whilst their role in immune interaction with the host is less established. Gram-positive pili are often posttranslationally modified by sortase-specific cleavage reactions and the formation of intramolecular peptide bonds. Here we report glycosylation as a new level of posttranslational modification of sortase-dependent pili of a beneficial microbiota species and its role in immune modulation. We focused on the SpaCBA pili of the model probiotic and beneficial human gut microbiota isolate Lactobacillus rhamnosus GG. A unique combination of molecular techniques, nanoscale mechanical and immunological approaches led to the identification of mannose and fucose residues on the SpaCBA pili. These glycans on the pili are recognized by human dendritic cells via the C-type lectin receptor DC-SIGN, a key carbohydrate-dependent immune tailoring pattern recognition receptor. This specific lectin-sugar interaction is moreover of functional importance and modulated the cytokine response of dendritic cells. This provides insight into the direct role bacterial glycoproteins can play in the immunomodulation of the host. Modification of the complex heterotrimeric pili of a model probiotic and microbiota isolate with mannose and fucose is of importance for the functional interaction with the host immune lectin receptor DC-SIGN on human dendritic cells. Our findings shed light on the yet underappreciated role of glycoconjugates in bacteria-host interactions.
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Affiliation(s)
- Hanne L. P. Tytgat
- Centre of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
- Department of Bioscience Engineering, Environmental Ecology & Applied Microbiology, University of Antwerp, Antwerp, Belgium
- Laboratory of Microbiology, Wageningen University, Wageningen, The Netherlands
| | - Nienke H. van Teijlingen
- Academic Medical Center, Department of Experimental Immunology, University of Amsterdam, Amsterdam, The Netherlands
| | - Ruby May A. Sullan
- Institute of Life Sciences, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | | | - Pia Rasinkangas
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
| | - Marcel Messing
- Immunobiology Research Program and Department of Bacteriology and Immunology, University of Helsinki, Helsinki, Finland
| | - Justus Reunanen
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
| | - Reetta Satokari
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
| | - Jos Vanderleyden
- Centre of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
| | - Yves F. Dufrêne
- Laboratory of Microbiology, Wageningen University, Wageningen, The Netherlands
| | - Teunis B. H. Geijtenbeek
- Academic Medical Center, Department of Experimental Immunology, University of Amsterdam, Amsterdam, The Netherlands
| | - Willem M. de Vos
- Laboratory of Microbiology, Wageningen University, Wageningen, The Netherlands
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
- Immunobiology Research Program and Department of Bacteriology and Immunology, University of Helsinki, Helsinki, Finland
| | - Sarah Lebeer
- Centre of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
- Department of Bioscience Engineering, Environmental Ecology & Applied Microbiology, University of Antwerp, Antwerp, Belgium
- * E-mail:
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25
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King JE, Roberts IS. Bacterial Surfaces: Front Lines in Host-Pathogen Interaction. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 915:129-56. [PMID: 27193542 DOI: 10.1007/978-3-319-32189-9_10] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
All bacteria are bound by at least one membrane that acts as a barrier between the cell's interior and the outside environment. Surface components within and attached to the cell membrane are essential for ensuring that the overall homeostasis of the cell is maintained. However, many surface components of the bacterial cell also have an indispensable role mediating interactions of the bacteria with their immediate environment and as such are essential to the pathogenesis of infectious disease. During the course of an infection, bacterial pathogens will encounter many different ecological niches where environmental conditions such as salinity, temperature, pH, and the availability of nutrients fluctuate. It is the bacterial cell surface that is at the front-line of these host-pathogen interactions often protecting the bacterium from hostile surroundings but at the same time playing a critical role in the adherence to host tissues promoting colonization and subsequent infection. To deal effectively with the changing environments that pathogens may encounter in different ecological niches within the host many of the surface components of the bacterial cell are subject to phenotypic variation resulting in heterogeneous subpopulations of bacteria within the clonal population. This dynamic phenotypic heterogeneity ensures that at least a small fraction of the population will be adapted for a particular circumstance should it arise. Diversity within the clonal population has often been masked by studies on entire bacterial populations where it was often assumed genes were expressed in a uniform manner. This chapter, therefore, aims to highlight the non-uniformity in certain cell surface structures and will discuss the implication of this heterogeneity in bacterial-host interaction. Some of the recent advances in studying bacterial surface structures at the single cell level will also be reviewed.
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Affiliation(s)
- Jane E King
- Faculty of Life Sciences, University of Manchester, Manchester, M13 9PT, UK
| | - Ian S Roberts
- Faculty of Life Sciences, University of Manchester, Manchester, M13 9PT, UK.
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26
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Reardon-Robinson ME, Osipiuk J, Jooya N, Chang C, Joachimiak A, Das A, Ton-That H. A thiol-disulfide oxidoreductase of the Gram-positive pathogen Corynebacterium diphtheriae is essential for viability, pilus assembly, toxin production and virulence. Mol Microbiol 2015; 98:1037-50. [PMID: 26294390 PMCID: PMC4981772 DOI: 10.1111/mmi.13172] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/19/2015] [Indexed: 12/19/2022]
Abstract
The Gram-positive pathogen Corynebacterium diphtheriae exports through the Sec apparatus many extracellular proteins that include the key virulence factors diphtheria toxin and the adhesive pili. How these proteins attain their native conformations after translocation as unfolded precursors remains elusive. The fact that the majority of these exported proteins contain multiple cysteine residues and that several membrane-bound oxidoreductases are encoded in the corynebacterial genome suggests the existence of an oxidative protein-folding pathway in this organism. Here we show that the shaft pilin SpaA harbors a disulfide bond in vivo and alanine substitution of these cysteines abrogates SpaA polymerization and leads to the secretion of degraded SpaA peptides. We then identified a thiol-disulfide oxidoreductase (MdbA), whose structure exhibits a conserved thioredoxin-like domain with a CPHC active site. Remarkably, deletion of mdbA results in a severe temperature-sensitive cell division phenotype. This mutant also fails to assemble pilus structures and is greatly defective in toxin production. Consistent with these defects, the ΔmdbA mutant is attenuated in a guinea pig model of diphtheritic toxemia. Given its diverse cellular functions in cell division, pilus assembly and toxin production, we propose that MdbA is a component of the general oxidative folding machine in C. diphtheriae.
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Affiliation(s)
- Melissa E. Reardon-Robinson
- Department of Microbiology & Molecular Genetics, University of Texas Health Science Center, Houston, TX, USA
| | - Jerzy Osipiuk
- Midwest Center for Structural Genomics, Department of Biosciences, Argonne National Laboratory, Argonne, IL, USA
- Structural Biology Center, Department of Biosciences, Argonne National Laboratory, Argonne, IL, USA
| | - Neda Jooya
- Department of Microbiology & Molecular Genetics, University of Texas Health Science Center, Houston, TX, USA
| | - Chungyu Chang
- Department of Microbiology & Molecular Genetics, University of Texas Health Science Center, Houston, TX, USA
| | - Andrzej Joachimiak
- Midwest Center for Structural Genomics, Department of Biosciences, Argonne National Laboratory, Argonne, IL, USA
- Structural Biology Center, Department of Biosciences, Argonne National Laboratory, Argonne, IL, USA
| | - Asis Das
- Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, CT, USA
| | - Hung Ton-That
- Department of Microbiology & Molecular Genetics, University of Texas Health Science Center, Houston, TX, USA
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27
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Corynebacterium ulcerans cutaneous diphtheria. THE LANCET. INFECTIOUS DISEASES 2015; 15:1100-1107. [PMID: 26189434 DOI: 10.1016/s1473-3099(15)00225-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Revised: 02/12/2015] [Accepted: 03/10/2015] [Indexed: 11/21/2022]
Abstract
We describe the case of a patient with cutaneous diphtheria caused by toxigenic Corynebacterium ulcerans who developed a right hand flexor sheath infection and symptoms of sepsis such as fever, tachycardia, and elevated C-reactive protein, after contact with domestic cats and dogs, and a fox. We summarise the epidemiology, clinical presentation, microbiology, diagnosis, therapy, and public health aspects of this disease, with emphasis on improving recognition. In many European countries, C ulcerans has become the organism commonly associated with cutaneous diphtheria, usually seen as an imported tropical disease or resulting from contact with domestic and agricultural animals. Diagnosis relies on bacterial culture and confirmation of toxin production, with management requiring appropriate antimicrobial therapy and prompt administration of antitoxin, if necessary. Early diagnosis is essential for implementation of control measures and clear guidelines are needed to assist clinicians in managing clinical diphtheria. This case was a catalyst to the redrafting of the 2014 national UK interim guidelines for the public health management of diphtheria, released as final guidelines in March, 2015.
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28
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Antunes CA, Sanches dos Santos L, Hacker E, Köhler S, Bösl K, Ott L, de Luna MDG, Hirata R, Azevedo VADC, Mattos-Guaraldi AL, Burkovski A. Characterization of DIP0733, a multi-functional virulence factor of Corynebacterium diphtheriae. MICROBIOLOGY-SGM 2015; 161:639-47. [PMID: 25635272 DOI: 10.1099/mic.0.000020] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Corynebacterium diphtheriae is typically recognized as an extracellular pathogen. However, a number of studies revealed its ability to invade epithelial cells, indicating a more complex pathogen-host interaction. The molecular mechanisms controlling and facilitating internalization of Cor. diphtheriae are poorly understood. In this study, we investigated the role of DIP0733 as virulence factor to elucidate how it contributes to the process of pathogen-host cell interaction. Based on in vitro experiments, it was suggested recently that the DIP0733 protein might be involved in adhesion, invasion of epithelial cells and induction of apoptosis. A corresponding Cor. diphtheriae mutant strain generated in this study was attenuated in its ability to colonize and kill the host in a Caenorhabditis elegans infection model system. Furthermore, the mutant showed an altered adhesion pattern and a drastically reduced ability to adhere and invade epithelial cells. Subsequent experiments showed an influence of DIP0733 on binding of Cor. diphtheriae to extracellular matrix proteins such as collagen and fibronectin. Furthermore, based on its fibrinogen-binding activity, DIP0733 may play a role in avoiding recognition of Cor. diphtheriae by the immune system. In summary, our findings support the idea that DIP0733 is a multi-functional virulence factor of Cor. diphtheriae.
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Affiliation(s)
- Camila Azevedo Antunes
- Mikrobiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany Departmento de Biologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | | | - Elena Hacker
- Mikrobiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Stefanie Köhler
- Mikrobiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Korbinian Bösl
- Mikrobiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Lisa Ott
- Mikrobiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | | | - Raphael Hirata
- Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Vasco Ariston de Carvalho Azevedo
- Departmento de Biologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | | | - Andreas Burkovski
- Mikrobiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
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29
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Heydari H, Siow CC, Tan MF, Jakubovics NS, Wee WY, Mutha NVR, Wong GJ, Ang MY, Yazdi AH, Choo SW. CoryneBase: Corynebacterium genomic resources and analysis tools at your fingertips. PLoS One 2014; 9:e86318. [PMID: 24466021 PMCID: PMC3895029 DOI: 10.1371/journal.pone.0086318] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Accepted: 12/11/2013] [Indexed: 11/22/2022] Open
Abstract
Corynebacteria are used for a wide variety of industrial purposes but some species are associated with human diseases. With increasing number of corynebacterial genomes having been sequenced, comparative analysis of these strains may provide better understanding of their biology, phylogeny, virulence and taxonomy that may lead to the discoveries of beneficial industrial strains or contribute to better management of diseases. To facilitate the ongoing research of corynebacteria, a specialized central repository and analysis platform for the corynebacterial research community is needed to host the fast-growing amount of genomic data and facilitate the analysis of these data. Here we present CoryneBase, a genomic database for Corynebacterium with diverse functionality for the analysis of genomes aimed to provide: (1) annotated genome sequences of Corynebacterium where 165,918 coding sequences and 4,180 RNAs can be found in 27 species; (2) access to comprehensive Corynebacterium data through the use of advanced web technologies for interactive web interfaces; and (3) advanced bioinformatic analysis tools consisting of standard BLAST for homology search, VFDB BLAST for sequence homology search against the Virulence Factor Database (VFDB), Pairwise Genome Comparison (PGC) tool for comparative genomic analysis, and a newly designed Pathogenomics Profiling Tool (PathoProT) for comparative pathogenomic analysis. CoryneBase offers the access of a range of Corynebacterium genomic resources as well as analysis tools for comparative genomics and pathogenomics. It is publicly available at http://corynebacterium.um.edu.my/.
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Affiliation(s)
- Hamed Heydari
- Genome Informatics Research Laboratory, HIR Building, University of Malaya, Kuala Lumpur, Malaysia
- Department of Software Engineering, Faculty of Computer Science and Information Technology, University of Malaya, Kuala Lumpur, Malaysia
| | - Cheuk Chuen Siow
- Genome Informatics Research Laboratory, HIR Building, University of Malaya, Kuala Lumpur, Malaysia
| | - Mui Fern Tan
- Genome Informatics Research Laboratory, HIR Building, University of Malaya, Kuala Lumpur, Malaysia
| | - Nick S. Jakubovics
- Centre for Oral Health Research, School of Dental Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne, United Kingdom
| | - Wei Yee Wee
- Genome Informatics Research Laboratory, HIR Building, University of Malaya, Kuala Lumpur, Malaysia
- Department of Oral Biology and Biomedical Sciences, Faculty of Dentistry, University of Malaya, Kuala Lumpur, Malaysia
| | - Naresh V. R. Mutha
- Genome Informatics Research Laboratory, HIR Building, University of Malaya, Kuala Lumpur, Malaysia
| | - Guat Jah Wong
- Genome Informatics Research Laboratory, HIR Building, University of Malaya, Kuala Lumpur, Malaysia
- Department of Oral Biology and Biomedical Sciences, Faculty of Dentistry, University of Malaya, Kuala Lumpur, Malaysia
| | - Mia Yang Ang
- Genome Informatics Research Laboratory, HIR Building, University of Malaya, Kuala Lumpur, Malaysia
- Department of Oral Biology and Biomedical Sciences, Faculty of Dentistry, University of Malaya, Kuala Lumpur, Malaysia
| | - Amir Hessam Yazdi
- Genome Informatics Research Laboratory, HIR Building, University of Malaya, Kuala Lumpur, Malaysia
- Department of Computer System & Technology, Faculty of Computer Science and Information Technology, University of Malaya, Kuala Lumpur, Malaysia
| | - Siew Woh Choo
- Genome Informatics Research Laboratory, HIR Building, University of Malaya, Kuala Lumpur, Malaysia
- Department of Oral Biology and Biomedical Sciences, Faculty of Dentistry, University of Malaya, Kuala Lumpur, Malaysia
- * E-mail:
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30
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Mak TN, Schmid M, Brzuszkiewicz E, Zeng G, Meyer R, Sfanos KS, Brinkmann V, Meyer TF, Brüggemann H. Comparative genomics reveals distinct host-interacting traits of three major human-associated propionibacteria. BMC Genomics 2013; 14:640. [PMID: 24053623 PMCID: PMC3848858 DOI: 10.1186/1471-2164-14-640] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Accepted: 09/17/2013] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Propionibacteria are part of the human microbiota. Many studies have addressed the predominant colonizer of sebaceous follicles of the skin, Propionibacterium acnes, and investigated its association with the skin disorder acne vulgaris, and lately with prostate cancer. Much less is known about two other propionibacterial species frequently found on human tissue sites, Propionibacterium granulosum and Propionibacterium avidum. Here we analyzed two and three genomes of P. granulosum and P. avidum, respectively, and compared them to two genomes of P. acnes; we further highlight differences among the three cutaneous species with proteomic and microscopy approaches. RESULTS Electron and atomic force microscopy revealed an exopolysaccharide (EPS)-like structure surrounding P. avidum cells, that is absent in P. acnes and P. granulosum. In contrast, P. granulosum possesses pili-like appendices, which was confirmed by surface proteome analysis. The corresponding genes were identified; they are clustered with genes encoding sortases. Both, P. granulosum and P. avidum lack surface or secreted proteins for predicted host-interacting factors of P. acnes, including several CAMP factors, sialidases, dermatan-sulphate adhesins, hyaluronidase and a SH3 domain-containing lipoprotein; accordingly, only P. acnes exhibits neuraminidase and hyaluronidase activities. These functions are encoded on previously unrecognized island-like regions in the genome of P. acnes. CONCLUSIONS Despite their omnipresence on human skin little is known about the role of cutaneous propionibacteria. All three species are associated with a variety of diseases, including postoperative and device-related abscesses and infections. We showed that the three organisms have evolved distinct features to interact with their human host. Whereas P. avidum and P. granulosum produce an EPS-like surface structure and pili-like appendices, respectively, P. acnes possesses a number of unique surface-exposed proteins with host-interacting properties. The different surface properties of the three cutaneous propionibacteria are likely to determine their colonizing ability and pathogenic potential on the skin and at non-skin sites.
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Affiliation(s)
- Tim N Mak
- Department of Biomedicine, Aarhus University, Aarhus, Denmark.
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31
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Pilus gene pool variation and the virulence of Corynebacterium diphtheriae clinical isolates during infection of a nematode. J Bacteriol 2013; 195:3774-83. [PMID: 23772071 DOI: 10.1128/jb.00500-13] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Toxigenic Corynebacterium diphtheriae strains cause diphtheria in humans. The toxigenic C. diphtheriae isolate NCTC13129 produces three distinct heterotrimeric pili that contain SpaA, SpaD, and SpaH, making up the shaft structure. The SpaA pili are known to mediate bacterial adherence to pharyngeal epithelial cells. However, to date little is known about the expression of different pili in various clinical isolates and their importance in bacterial pathogenesis. Here, we characterized a large collection of C. diphtheriae clinical isolates for their pilin gene pool by PCR and for the expression of the respective pilins by immunoblotting with antibodies against Spa pilins. Consistent with the role of a virulence factor, the SpaA-type pili were found to be prevalent among the isolates, and most significantly, corynebacterial adherence to pharyngeal epithelial cells was strictly correlated with isolates that were positive for the SpaA pili. By comparison, the isolates were heterogeneous for the presence of SpaD- and SpaH-type pili. Importantly, using Caenorhabditis elegans as a model host for infection, we show here that strain NCTC13129 rapidly killed the nematodes, the phenotype similar to isolates that were positive for toxin and all pilus types. In contrast, isogenic mutants of NCTC13129 lacking SpaA-type pili or devoid of toxin and SpaA pili exhibited delayed killing of nematodes with similar kinetics. Consistently, nontoxigenic or toxigenic isolates that lack one, two, or all three pilus types were also attenuated in virulence. This work signifies the important role of pili in corynebacterial pathogenesis and provides a simple host model to identify additional virulence factors.
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32
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Cell envelope of corynebacteria: structure and influence on pathogenicity. ISRN MICROBIOLOGY 2013; 2013:935736. [PMID: 23724339 PMCID: PMC3658426 DOI: 10.1155/2013/935736] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2012] [Accepted: 12/31/2012] [Indexed: 11/18/2022]
Abstract
To date the genus Corynebacterium comprises 88 species. More than half of these are connected to human and animal infections, with the most prominent member of the pathogenic species being Corynebacterium diphtheriae, which is also the type species of the genus. Corynebacterium species are characterized by a complex cell wall architecture: the plasma membrane of these bacteria is followed by a peptidoglycan layer, which itself is covalently linked to a polymer of arabinogalactan. Bound to this, an outer layer of mycolic acids is found which is functionally equivalent to the outer membrane of Gram-negative bacteria. As final layer, free polysaccharides, glycolipids, and proteins are found. The composition of the different substructures of the corynebacterial cell envelope and their influence on pathogenicity are discussed in this paper.
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Abstract
Pili or fimbriae are recognized as essential virulence determinants assembled on the bacterial surface. Gram-positive bacteria produce covalently linked pilus structures that are distinct from gram-negative counterparts. In this chapter, we describe three commonly used techniques to extract, detect, and visualize pili from gram-positive bacteria: (1) Western blot analysis, (2) Immuno-Electron Microscopy, and (3) Atomic Force Microscopy.
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34
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Danne C, Dramsi S. Pili of gram-positive bacteria: roles in host colonization. Res Microbiol 2012; 163:645-58. [PMID: 23116627 DOI: 10.1016/j.resmic.2012.10.012] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Accepted: 10/11/2012] [Indexed: 02/06/2023]
Abstract
In the last decade, pili, which are encoded within pathogenicity islands, have been found in many Gram-positive bacteria, including the major streptococcal and enterococcal pathogens. These long proteinaceous polymers extending from the bacterial surface are constituted of covalently linked pilin subunits, which play major roles in adhesion and host colonization. They are also involved in biofilm formation, a characteristic life-style of the bacteria constituting the oral flora. Pili are highly immunogenic structures that are under the selective pressure of host immune responses. Indeed, pilus expression was found to be heterogeneous in several bacteria with the co-existence of two subpopulations expressing various levels of pili. The molecular mechanisms underlying this complex regulation are poorly characterized except for Streptococcus pneumoniae. In this review, we will discuss the roles of Gram-positive bacteria pili in adhesion to host extracellular matrix proteins, tissue tropism, biofilm formation, modulation of innate immune responses and their contribution to virulence, and in a second part the regulation of their expression. This overview should help to understand the rise of pili as an intensive field of investigation and pinpoints the areas that need further study.
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Affiliation(s)
- Camille Danne
- Institut Pasteur, Unité de Biologie des Bactéries Pathogènes à Gram-positif, Paris F-75015, France
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Rheinlaender J, Gräbner A, Ott L, Burkovski A, Schäffer TE. Contour and persistence length of Corynebacterium diphtheriae pili by atomic force microscopy. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2012; 41:561-70. [DOI: 10.1007/s00249-012-0818-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Revised: 04/05/2012] [Accepted: 04/21/2012] [Indexed: 10/28/2022]
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Schröder J, Maus I, Meyer K, Wördemann S, Blom J, Jaenicke S, Schneider J, Trost E, Tauch A. Complete genome sequence, lifestyle, and multi-drug resistance of the human pathogen Corynebacterium resistens DSM 45100 isolated from blood samples of a leukemia patient. BMC Genomics 2012; 13:141. [PMID: 22524407 PMCID: PMC3350403 DOI: 10.1186/1471-2164-13-141] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2011] [Accepted: 04/23/2012] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Corynebacterium resistens was initially recovered from human infections and recognized as a new coryneform species that is highly resistant to antimicrobial agents. Bacteremia associated with this organism in immunocompromised patients was rapidly fatal as standard minocycline therapies failed. C. resistens DSM 45100 was isolated from a blood culture of samples taken from a patient with acute myelocytic leukemia. The complete genome sequence of C. resistens DSM 45100 was determined by pyrosequencing to identify genes contributing to multi-drug resistance, virulence, and the lipophilic lifestyle of this newly described human pathogen. RESULTS The genome of C. resistens DSM 45100 consists of a circular chromosome of 2,601,311 bp in size and the 28,312-bp plasmid pJA144188. Metabolic analysis showed that the genome of C. resistens DSM 45100 lacks genes for typical sugar uptake systems, anaplerotic functions, and a fatty acid synthase, explaining the strict lipophilic lifestyle of this species. The genome encodes a broad spectrum of enzymes ensuring the availability of exogenous fatty acids for growth, including predicted virulence factors that probably contribute to fatty acid metabolism by damaging host tissue. C. resistens DSM 45100 is able to use external L-histidine as a combined carbon and nitrogen source, presumably as a result of adaptation to the hitherto unknown habitat on the human skin. Plasmid pJA144188 harbors several genes contributing to antibiotic resistance of C. resistens DSM 45100, including a tetracycline resistance region of the Tet W type known from Lactobacillus reuteri and Streptococcus suis. The tet(W) gene of pJA144188 was cloned in Corynebacterium glutamicum and was shown to confer high levels of resistance to tetracycline, doxycycline, and minocycline in vitro. CONCLUSIONS The detected gene repertoire of C. resistens DSM 45100 provides insights into the lipophilic lifestyle and virulence functions of this newly recognized pathogen. Plasmid pJA144188 revealed a modular architecture of gene regions that contribute to the multi-drug resistance of C. resistens DSM 45100. The tet(W) gene encoding a ribosomal protection protein is reported here for the first time in corynebacteria. Cloning of the tet(W) gene mediated resistance to second generation tetracyclines in C. glutamicum, indicating that it might be responsible for the failure of minocycline therapies in patients with C. resistens bacteremia.
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Affiliation(s)
- Jasmin Schröder
- Institut für Genomforschung und Systembiologie, Centrum für Biotechnologie, Universität Bielefeld, Germany
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Ott L, McKenzie A, Baltazar MT, Britting S, Bischof A, Burkovski A, Hoskisson PA. Evaluation of invertebrate infection models for pathogenic corynebacteria. ACTA ACUST UNITED AC 2012; 65:413-21. [PMID: 22443092 DOI: 10.1111/j.1574-695x.2012.00963.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Revised: 03/08/2012] [Accepted: 03/09/2012] [Indexed: 02/02/2023]
Abstract
For several pathogenic bacteria, model systems for host-pathogen interactions were developed, which provide the possibility of quick and cost-effective high throughput screening of mutant bacteria for genes involved in pathogenesis. A number of different model systems, including amoeba, nematodes, insects, and fish, have been introduced, and it was observed that different bacteria respond in different ways to putative surrogate hosts, and distinct model systems might be more or less suitable for a certain pathogen. The aim of this study was to develop a suitable invertebrate model for the human and animal pathogens Corynebacterium diphtheriae, Corynebacterium pseudotuberculosis, and Corynebacterium ulcerans. The results obtained in this study indicate that Acanthamoeba polyphaga is not optimal as surrogate host, while both Caenorhabtitis elegans and Galleria larvae seem to offer tractable models for rapid assessment of virulence between strains. Caenorhabtitis elegans gives more differentiated results and might be the best model system for pathogenic corynebacteria, given the tractability of bacteria and the range of mutant nematodes available to investigate the host response in combination with bacterial virulence. Nevertheless, Galleria will also be useful in respect to innate immune responses to pathogens because insects offer a more complex cell-based innate immune system compared with the simple innate immune system of C. elegans.
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Affiliation(s)
- Lisa Ott
- Lehrstuhl für Mikrobiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
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Pangenomic study of Corynebacterium diphtheriae that provides insights into the genomic diversity of pathogenic isolates from cases of classical diphtheria, endocarditis, and pneumonia. J Bacteriol 2012; 194:3199-215. [PMID: 22505676 DOI: 10.1128/jb.00183-12] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Corynebacterium diphtheriae is one of the most prominent human pathogens and the causative agent of the communicable disease diphtheria. The genomes of 12 strains isolated from patients with classical diphtheria, endocarditis, and pneumonia were completely sequenced and annotated. Including the genome of C. diphtheriae NCTC 13129, we herewith present a comprehensive comparative analysis of 13 strains and the first characterization of the pangenome of the species C. diphtheriae. Comparative genomics showed extensive synteny and revealed a core genome consisting of 1,632 conserved genes. The pangenome currently comprises 4,786 protein-coding regions and increases at an average of 65 unique genes per newly sequenced strain. Analysis of prophages carrying the diphtheria toxin gene tox revealed that the toxoid vaccine producer C. diphtheriae Park-Williams no. 8 has been lysogenized by two copies of the ω(tox)(+) phage, whereas C. diphtheriae 31A harbors a hitherto-unknown tox(+) corynephage. DNA binding sites of the tox-controlling regulator DtxR were detected by genome-wide motif searches. Comparative content analysis showed that the DtxR regulons exhibit marked differences due to gene gain, gene loss, partial gene deletion, and DtxR binding site depletion. Most predicted pathogenicity islands of C. diphtheriae revealed characteristics of horizontal gene transfer. The majority of these islands encode subunits of adhesive pili, which can play important roles in adhesion of C. diphtheriae to different host tissues. All sequenced isolates contain at least two pilus gene clusters. It appears that variation in the distributed genome is a common strategy of C. diphtheriae to establish differences in host-pathogen interactions.
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