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Orgeur M, Sous C, Madacki J, Brosch R. Evolution and emergence of Mycobacterium tuberculosis. FEMS Microbiol Rev 2024; 48:fuae006. [PMID: 38365982 PMCID: PMC10906988 DOI: 10.1093/femsre/fuae006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 01/12/2024] [Accepted: 02/13/2024] [Indexed: 02/18/2024] Open
Abstract
Tuberculosis (TB) remains one of the deadliest infectious diseases in human history, prevailing even in the 21st century. The causative agents of TB are represented by a group of closely related bacteria belonging to the Mycobacterium tuberculosis complex (MTBC), which can be subdivided into several lineages of human- and animal-adapted strains, thought to have shared a last common ancestor emerged by clonal expansion from a pool of recombinogenic Mycobacterium canettii-like tubercle bacilli. A better understanding of how MTBC populations evolved from less virulent mycobacteria may allow for discovering improved TB control strategies and future epidemiologic trends. In this review, we highlight new insights into the evolution of mycobacteria at the genus level, describing different milestones in the evolution of mycobacteria, with a focus on the genomic events that have likely enabled the emergence and the dominance of the MTBC. We also review the recent literature describing the various MTBC lineages and highlight their particularities and differences with a focus on host preferences and geographic distribution. Finally, we discuss on putative mechanisms driving the evolution of tubercle bacilli and mycobacteria in general, by taking the mycobacteria-specific distributive conjugal transfer as an example.
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Affiliation(s)
- Mickael Orgeur
- Institut Pasteur, Université Paris Cité, CNRS UMR 6047, Unit for Integrated Mycobacterial Pathogenomics, 75015 Paris, France
| | - Camille Sous
- Institut Pasteur, Université Paris Cité, CNRS UMR 6047, Unit for Integrated Mycobacterial Pathogenomics, 75015 Paris, France
| | - Jan Madacki
- Institut Pasteur, Université Paris Cité, CNRS UMR 6047, Unit for Integrated Mycobacterial Pathogenomics, 75015 Paris, France
- Institut Pasteur, Université Paris Cité, CNRS UMR 2000, Unit for Human Evolutionary Genetics, 75015 Paris, France
| | - Roland Brosch
- Institut Pasteur, Université Paris Cité, CNRS UMR 6047, Unit for Integrated Mycobacterial Pathogenomics, 75015 Paris, France
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Charubin K, Hill JD, Papoutsakis ET. DNA transfer between two different species mediated by heterologous cell fusion in Clostridium coculture. mBio 2024; 15:e0313323. [PMID: 38214507 PMCID: PMC10865971 DOI: 10.1128/mbio.03133-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 12/01/2023] [Indexed: 01/13/2024] Open
Abstract
Prokaryotic evolution is driven by random mutations and horizontal gene transfer (HGT). HGT occurs via transformation, transduction, or conjugation. We have previously shown that in syntrophic cocultures of Clostridium acetobutylicum and Clostridium ljungdahlii, heterologous cell fusion leads to a large-scale exchange of proteins and RNA between the two organisms. Here, we present evidence that heterologous cell fusion facilitates the exchange of DNA between the two organisms. Using selective subculturing, we isolated C. acetobutylicum cells which acquired and integrated into their genome portions of plasmid DNA from a plasmid-carrying C. ljungdahlii strain. Limiting-dilution plating and DNA methylation data based on PacBio Single-Molecule Real Time (SMRT) sequencing support the existence of hybrid C. acetobutylicum/C. ljungdahlii cells. These findings expand our understanding of multi-species microbiomes, their survival strategies, and evolution.IMPORTANCEInvestigations of natural multispecies microbiomes and synthetic microbial cocultures are attracting renewed interest for their potential application in biotechnology, ecology, and medical fields. Previously, we have shown the syntrophic coculture of C. acetobutylicum and C. ljungdahlii undergoes heterologous cell-to-cell fusion, which facilitates the exchange of cytoplasmic protein and RNA between the two organisms. We now show that heterologous cell fusion between the two Clostridium organisms can facilitate the exchange of DNA. By applying selective pressures to this coculture system, we isolated clones of wild-type C. acetobutylicum which acquired the erythromycin resistance (erm) gene from the C. ljungdahlii strain carrying a plasmid with the erm gene. Single-molecule real-time sequencing revealed that the erm gene was integrated into the genome in a mosaic fashion. Our data also support the persistence of hybrid C. acetobutylicum/C. ljungdahlii cells displaying hybrid DNA-methylation patterns.
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Affiliation(s)
- Kamil Charubin
- Department of Chemical and Biomolecular Engineering, The Delaware Biotechnology Institute, University of Delaware, Newark, Delaware, USA
| | - John D. Hill
- Department of Chemical and Biomolecular Engineering, The Delaware Biotechnology Institute, University of Delaware, Newark, Delaware, USA
| | - Eleftherios Terry Papoutsakis
- Department of Chemical and Biomolecular Engineering, The Delaware Biotechnology Institute, University of Delaware, Newark, Delaware, USA
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3
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Ilyas M, Purkait D, Atmakuri K. Genomic islands and their role in fitness traits of two key sepsis-causing bacterial pathogens. Brief Funct Genomics 2024; 23:55-68. [PMID: 36528816 DOI: 10.1093/bfgp/elac051] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 11/03/2022] [Accepted: 11/11/2022] [Indexed: 01/21/2024] Open
Abstract
To survive and establish a niche for themselves, bacteria constantly evolve. Toward that, they not only insert point mutations and promote illegitimate recombinations within their genomes but also insert pieces of 'foreign' deoxyribonucleic acid, which are commonly referred to as 'genomic islands' (GEIs). The GEIs come in several forms, structures and types, often providing a fitness advantage to the harboring bacterium. In pathogenic bacteria, some GEIs may enhance virulence, thus altering disease burden, morbidity and mortality. Hence, delineating (i) the GEIs framework, (ii) their encoded functions, (iii) the triggers that help them move, (iv) the mechanisms they exploit to move among bacteria and (v) identification of their natural reservoirs will aid in superior tackling of several bacterial diseases, including sepsis. Given the vast array of comparative genomics data, in this short review, we provide an overview of the GEIs, their types and the compositions therein, especially highlighting GEIs harbored by two important pathogens, viz. Acinetobacter baumannii and Klebsiella pneumoniae, which prominently trigger sepsis in low- and middle-income countries. Our efforts help shed some light on the challenges these pathogens pose when equipped with GEIs. We hope that this review will provoke intense research into understanding GEIs, the cues that drive their mobility across bacteria and the ways and means to prevent their transfer, especially across pathogenic bacteria.
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Affiliation(s)
- Mohd Ilyas
- Bacterial Pathogenesis Lab, Infection and Immunity Group, Translational Health Science and Technology Institute, NCR Biotech Science Cluster, Faridabad, Haryana 121001, India
| | - Dyuti Purkait
- Bacterial Pathogenesis Lab, Infection and Immunity Group, Translational Health Science and Technology Institute, NCR Biotech Science Cluster, Faridabad, Haryana 121001, India
| | - Krishnamohan Atmakuri
- Bacterial Pathogenesis Lab, Infection and Immunity Group, Translational Health Science and Technology Institute, NCR Biotech Science Cluster, Faridabad, Haryana 121001, India
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4
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Derbyshire KM, Salfinger M. Plasmid-mediated drug resistance in mycobacteria: the tip of the iceberg? J Clin Microbiol 2023; 61:e0062823. [PMID: 37724858 PMCID: PMC10595058 DOI: 10.1128/jcm.00628-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/21/2023] Open
Abstract
Macrolides, such as clarithromycin, are crucial in the treatment of nontuberculous mycobacteria (NTM). NTM are notoriously innately drug resistant, which has made the dependence on macrolides for their treatment even more important. Not surprisingly, resistance to macrolides has been documented in some NTM, including Mycobacterium avium and Mycobacterium abscessus, which are the two NTM species most often identified in clinical isolates. Resistance is mediated by point mutations in the 23S ribosomal RNA or by methylation of the rRNA by a methylase (encoded by an erm gene). Chromosomally encoded erm genes have been identified in many of the macrolide-resistant isolates, but not in Mycobacterium chelonae. Now, Brown-Elliott et al. (J Clin Microbiol 61:e00428-23, 2023, https://doi.org/10.1128/JCM.00428-23) describe the identification of a new erm variant, erm(55), which was found either on the chromosome or on a plasmid in highly macrolide-resistant clinical isolates of M. chelonae. The chromosomal erm(55) gene appears to be associated with mobile elements; one gene is within a putative transposon and the second is in a large (37 kb) insertion/deletion. The plasmid carrying erm(55) also encodes type IV and type VII secretion systems, which are often linked on large mycobacterial plasmids and are hypothesized to mediate plasmid transfer. While the conjugative transfer of the erm(55)-containing plasmid between NTM has yet to be demonstrated, the inferences are clear, as evidenced by the dissemination of plasmid-mediated drug resistance in other medically important bacteria. Here, we discuss the findings of Brown-Elliott et al., and the potential ramifications on treatment of NTM infections.
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Affiliation(s)
- Keith M. Derbyshire
- Division of Genetics, Wadsworth Center, New York State Department of Health, Albany, New York, USA
- Department of Biomedical Sciences, University at Albany, Albany, New York, USA
| | - Max Salfinger
- College of Public Health, University of South Florida, Tampa, Florida, USA
- Division of Infectious Disease and International Medicine, Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
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5
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Bravo A, Moreno-Blanco A, Espinosa M. One Earth: The Equilibrium between the Human and the Bacterial Worlds. Int J Mol Sci 2023; 24:15047. [PMID: 37894729 PMCID: PMC10606248 DOI: 10.3390/ijms242015047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 09/21/2023] [Accepted: 09/25/2023] [Indexed: 10/29/2023] Open
Abstract
Misuse and abuse of antibiotics on humans, cattle, and crops have led to the selection of multi-resistant pathogenic bacteria, the most feared 'superbugs'. Infections caused by superbugs are progressively difficult to treat, with a subsequent increase in lethality: the toll on human lives is predicted to reach 10 million by 2050. Here we review three concepts linked to the growing resistance to antibiotics, namely (i) the Resistome, which refers to the collection of bacterial genes that confer resistance to antibiotics, (ii) the Mobilome, which includes all the mobile genetic elements that participate in the spreading of antibiotic resistance among bacteria by horizontal gene transfer processes, and (iii) the Nichome, which refers to the set of genes that are expressed when bacteria try to colonize new niches. We also discuss the strategies that can be used to tackle bacterial infections and propose an entente cordiale with the bacterial world so that instead of war and destruction of the 'fierce enemy' we can achieve a peaceful coexistence (the One Earth concept) between the human and the bacterial worlds. This, in turn, will contribute to microbial biodiversity, which is crucial in a globally changing climate due to anthropogenic activities.
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Affiliation(s)
- Alicia Bravo
- Centro de Investigaciones Biológicas Margarita Salas, Consejo Superior de Investigaciones Científicas (CSIC), Ramiro de Maeztu 9, E-28040 Madrid, Spain
| | | | - Manuel Espinosa
- Centro de Investigaciones Biológicas Margarita Salas, Consejo Superior de Investigaciones Científicas (CSIC), Ramiro de Maeztu 9, E-28040 Madrid, Spain
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Gessner S, Martin ZAM, Reiche MA, Santos JA, Dinkele R, Ramudzuli A, Dhar N, de Wet TJ, Anoosheh S, Lang DM, Aaron J, Chew TL, Herrmann J, Müller R, McKinney JD, Woodgate R, Mizrahi V, Venclovas Č, Lamers MH, Warner DF. Investigating the composition and recruitment of the mycobacterial ImuA'-ImuB-DnaE2 mutasome. eLife 2023; 12:e75628. [PMID: 37530405 PMCID: PMC10421592 DOI: 10.7554/elife.75628] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 08/01/2023] [Indexed: 08/03/2023] Open
Abstract
A DNA damage-inducible mutagenic gene cassette has been implicated in the emergence of drug resistance in Mycobacterium tuberculosis during anti-tuberculosis (TB) chemotherapy. However, the molecular composition and operation of the encoded 'mycobacterial mutasome' - minimally comprising DnaE2 polymerase and ImuA' and ImuB accessory proteins - remain elusive. Following exposure of mycobacteria to DNA damaging agents, we observe that DnaE2 and ImuB co-localize with the DNA polymerase III β subunit (β clamp) in distinct intracellular foci. Notably, genetic inactivation of the mutasome in an imuBAAAAGG mutant containing a disrupted β clamp-binding motif abolishes ImuB-β clamp focus formation, a phenotype recapitulated pharmacologically by treating bacilli with griselimycin and in biochemical assays in which this β clamp-binding antibiotic collapses pre-formed ImuB-β clamp complexes. These observations establish the essentiality of the ImuB-β clamp interaction for mutagenic DNA repair in mycobacteria, identifying the mutasome as target for adjunctive therapeutics designed to protect anti-TB drugs against emerging resistance.
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Affiliation(s)
- Sophia Gessner
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
| | - Zela Alexandria-Mae Martin
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
- Laboratory of Microbiology and Microsystems, School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL)LausanneSwitzerland
| | - Michael A Reiche
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
- Advanced Imaging Center, Howard Hughes Medical InstituteAshburnUnited States
| | - Joana A Santos
- Department of Cell and Chemical Biology, Leiden University Medical CenterLeidenNetherlands
| | - Ryan Dinkele
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
| | - Atondaho Ramudzuli
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
| | - Neeraj Dhar
- Laboratory of Microbiology and Microsystems, School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL)LausanneSwitzerland
| | - Timothy J de Wet
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
- Department of Integrative Biomedical Sciences, University of Cape TownCape TownSouth Africa
| | - Saber Anoosheh
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
| | - Dirk M Lang
- Confocal and Light Microscope Imaging Facility, Department of Human Biology, University of Cape TownCape TownSouth Africa
| | - Jesse Aaron
- Advanced Imaging Center, Howard Hughes Medical InstituteAshburnUnited States
| | - Teng-Leong Chew
- Advanced Imaging Center, Howard Hughes Medical InstituteAshburnUnited States
| | - Jennifer Herrmann
- Helmholtz Centre for Infection Research, Helmholtz Institute for Pharmaceutical Research SaarlandSaarbrückenGermany
- German Centre for Infection Research (DZIF), Partner Site Hannover-BraunschweigBraunschweigGermany
| | - Rolf Müller
- Helmholtz Centre for Infection Research, Helmholtz Institute for Pharmaceutical Research SaarlandSaarbrückenGermany
- German Centre for Infection Research (DZIF), Partner Site Hannover-BraunschweigBraunschweigGermany
| | - John D McKinney
- Laboratory of Microbiology and Microsystems, School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL)LausanneSwitzerland
| | - Roger Woodgate
- Laboratory of Genomic Integrity, Eunice Kennedy Shriver National Institute of Child Health and Human DevelopmentBethesdaUnited States
| | - Valerie Mizrahi
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
- Wellcome Centre for Infectious Diseases Research in Africa, University of Cape TownCape TownSouth Africa
| | | | - Meindert H Lamers
- Department of Cell and Chemical Biology, Leiden University Medical CenterLeidenNetherlands
| | - Digby F Warner
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
- Wellcome Centre for Infectious Diseases Research in Africa, University of Cape TownCape TownSouth Africa
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7
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Brown-Elliott BA, Wallace RJ, Wengenack NL, Workman SD, Cameron ADS, Bush G, Hughes MD, Melton S, Gonzalez-Ramirez B, Rodriguez E, Somayaji K, Klapperich C, Viers M, Bolaji AJ, Rempel E, Alexander DC. Emergence of Inducible Macrolide Resistance in Mycobacterium chelonae Due to Broad-Host-Range Plasmid and Chromosomal Variants of the Novel 23S rRNA Methylase Gene, erm(55). J Clin Microbiol 2023; 61:e0042823. [PMID: 37347171 PMCID: PMC10358161 DOI: 10.1128/jcm.00428-23] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 05/31/2023] [Indexed: 06/23/2023] Open
Abstract
Macrolides are a mainstay of therapy for infections due to nontuberculous mycobacteria (NTM). Among rapidly growing mycobacteria (RGM), inducible macrolide resistance is associated with four chromosomal 23S rRNA methylase (erm) genes. Beginning in 2018, we detected high-level inducible clarithromycin resistance (MICs of ≥16μg/mL) in clinical isolates of Mycobacterium chelonae, an RGM species not previously known to contain erm genes. Using whole-genome sequencing, we identified a novel plasmid-mediated erm gene. This gene, designated erm(55)P, exhibits <65% amino acid identity to previously described RGM erm genes. Two additional chromosomal erm(55) alleles, with sequence identities of 81% to 86% to erm(55)P, were also identified and designated erm(55)C and erm(55)T. The erm(55)T is part of a transposon. The erm(55)P allele variant is located on a putative 137-kb conjugative plasmid, pMchErm55. Evaluation of 133 consecutive isolates from 2020 to 2022 revealed 5 (3.8%) with erm(55). The erm(55)P gene was also identified in public data sets of two emerging pathogenic pigmented RGM species: Mycobacterium iranicum and Mycobacterium obuense, dating back to 2008. In both species, the gene appeared to be present on plasmids homologous to pMchErm55. Plasmid-mediated macrolide resistance, not described previously for any NTM species, appears to have spread to multiple RGM species. This has important implications for antimicrobial susceptibility guidelines and treatment of RGM infections. Further spread could present serious consequences for treatment of other macrolide-susceptible RGM. Additional studies are needed to determine the transmissibility of pMchErm55 and the distribution of erm(55) among other RGM species.
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Affiliation(s)
- Barbara A. Brown-Elliott
- Mycobacteria/Nocardia Research Laboratory, University of Texas Health Science Center at Tyler, Tyler, Texas, USA
| | - Richard J. Wallace
- Mycobacteria/Nocardia Research Laboratory, University of Texas Health Science Center at Tyler, Tyler, Texas, USA
| | - Nancy L. Wengenack
- Division of Clinical Microbiology, Mayo Clinic, Rochester, Minnesota, USA
| | - Sean D. Workman
- Department of Biology, University of Regina, Regina, Saskatchewan, Canada
| | | | - Georgie Bush
- Mycobacteria/Nocardia Research Laboratory, University of Texas Health Science Center at Tyler, Tyler, Texas, USA
| | - M. Dolores Hughes
- Mycobacteria/Nocardia Research Laboratory, University of Texas Health Science Center at Tyler, Tyler, Texas, USA
| | - Stephanie Melton
- Mycobacteria/Nocardia Research Laboratory, University of Texas Health Science Center at Tyler, Tyler, Texas, USA
| | - Bibiana Gonzalez-Ramirez
- Mycobacteria/Nocardia Research Laboratory, University of Texas Health Science Center at Tyler, Tyler, Texas, USA
| | - Eliana Rodriguez
- Mycobacteria/Nocardia Research Laboratory, University of Texas Health Science Center at Tyler, Tyler, Texas, USA
| | - Kavya Somayaji
- Mycobacteria/Nocardia Research Laboratory, University of Texas Health Science Center at Tyler, Tyler, Texas, USA
| | | | - Mary Viers
- Division of Clinical Microbiology, Mayo Clinic, Rochester, Minnesota, USA
| | - Ayooluwa J. Bolaji
- Cadham Provincial Laboratory, Diagnostic Services, Shared Health, Winnipeg, Manitoba, Canada
| | - Emma Rempel
- Cadham Provincial Laboratory, Diagnostic Services, Shared Health, Winnipeg, Manitoba, Canada
| | - David C. Alexander
- Cadham Provincial Laboratory, Diagnostic Services, Shared Health, Winnipeg, Manitoba, Canada
- Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, Canada
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Brenner E, Sreevatsan S. Cold Cas: reevaluating the occurrence of CRISPR/Cas systems in Mycobacteriaceae. Front Microbiol 2023; 14:1204838. [PMID: 37440893 PMCID: PMC10333696 DOI: 10.3389/fmicb.2023.1204838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 05/22/2023] [Indexed: 07/15/2023] Open
Abstract
Bacterial CRISPR/Cas systems target foreign genetic elements such as phages and regulate gene expression by some pathogens, even in the host. The system is a marker for evolutionary history and has been used for inferences in Mycobacterium tuberculosis for 30 years. However, knowledge about mycobacterial CRISPR/Cas systems remains limited. It is believed that Type III-A Cas systems are exclusive to Mycobacterium canettii and the M. tuberculosis complex (MTBC) of organisms and that very few of the >200 diverse species of non-tuberculous mycobacteria (NTM) possess any CRISPR/Cas system. This study sought unreported CRISPR/Cas loci across NTM to better understand mycobacterial evolution, particularly in species phylogenetically near the MTBC. An analysis of available mycobacterial genomes revealed that Cas systems are widespread across Mycobacteriaceae and that some species contain multiple types. The phylogeny of Cas loci shows scattered presence in many NTM, with variation even within species, suggesting gains/losses of these loci occur frequently. Cas Type III-A systems were identified in pathogenic Mycobacterium heckeshornense and the geological environmental isolate Mycobacterium SM1. In summary, mycobacterial CRISPR/Cas systems are numerous, Type III-A systems are unreliable as markers for MTBC evolution, and mycobacterial horizontal gene transfer appears to be a frequent source of genetic variation.
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Affiliation(s)
| | - Srinand Sreevatsan
- Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI, United States
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Redman RM, Maughan TD, Smith CB, Crossno PF, Granger DL. Development of multidrug-resistant Mycobacterium tuberculosis in the biofilm of a peritoneal-venous shunt. IDCases 2023; 32:e01801. [PMID: 37250376 PMCID: PMC10209681 DOI: 10.1016/j.idcr.2023.e01801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 05/13/2023] [Accepted: 05/16/2023] [Indexed: 05/31/2023] Open
Abstract
A patient with ascites received a peritoneal-venous shunt for presumed cirrhosis, however surgical specimens grew Mycobacterium tuberculosis (MTb) sensitive to all anti-tuberculous drugs. Directly-Observed-Therapy (DOT) led to improvement followed by relapse with multidrug resistant MTb (MDRTB). We discuss pathways for selection of MDRTB within mycobacterial biofilm. This case illustrates the potential for development of MDRTB in patients with long-term indwelling catheters. We emphasize catheter removal and if not possible continuing follow-up for symptoms and signs of relapse.
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Affiliation(s)
- Romany M. Redman
- Department of Internal Medicine, University of Utah School of Medicine, 30 North 1900 East, Salt Lake City, UT 84145, USA
| | - Timothy D. Maughan
- Infectious Diseases Clinic, Providence Sacred Heart Hospital, 101 West 8th Avenue, Spokane, WA 99204, USA
| | - Charles B. Smith
- Division of Infectious Diseases, Department of Internal Medicine, University of Utah School of Medicine, 30 North 1900 East, Salt Lake City, UT 84132, USA
- Veterans Affairs Medical Center, 500 Foothill Drive, Salt Lake City, UT 84145, USA
| | - Peter F. Crossno
- Division of Pulmonary Medicine, Department of Medicine, Intermountain Healthcare, 5121 Cottonwood Street, Murray, UT 84107, USA
| | - Donald L. Granger
- Division of Infectious Diseases, Department of Internal Medicine, University of Utah School of Medicine, 30 North 1900 East, Salt Lake City, UT 84132, USA
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Abstract
The genus Mycobacterium contains several slow-growing human pathogens, including Mycobacterium tuberculosis, Mycobacterium leprae, and Mycobacterium avium. Mycobacterium smegmatis is a nonpathogenic and fast growing species within this genus. In 1990, a mutant of M. smegmatis, designated mc2155, that could be transformed with episomal plasmids was isolated, elevating M. smegmatis to model status as the ideal surrogate for mycobacterial research. Classical bacterial models, such as Escherichia coli, were inadequate for mycobacteria research because they have low genetic conservation, different physiology, and lack the novel envelope structure that distinguishes the Mycobacterium genus. By contrast, M. smegmatis encodes thousands of conserved mycobacterial gene orthologs and has the same cell architecture and physiology. Dissection and characterization of conserved genes, structures, and processes in genetically tractable M. smegmatis mc2155 have since provided previously unattainable insights on these same features in its slow-growing relatives. Notably, tuberculosis (TB) drugs, including the first-line drugs isoniazid and ethambutol, are active against M. smegmatis, but not against E. coli, allowing the identification of their physiological targets. Furthermore, Bedaquiline, the first new TB drug in 40 years, was discovered through an M. smegmatis screen. M. smegmatis has become a model bacterium, not only for M. tuberculosis, but for all other Mycobacterium species and related genera. With a repertoire of bioinformatic and physical resources, including the recently established Mycobacterial Systems Resource, M. smegmatis will continue to accelerate mycobacterial research and advance the field of microbiology.
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11
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Renau-Mínguez C, Herrero-Abadía P, Ruiz-Rodriguez P, Sentandreu V, Torrents E, Chiner-Oms Á, Torres-Puente M, Comas I, Julián E, Coscolla M. Genomic analysis of Mycobacterium brumae sustains its nonpathogenic and immunogenic phenotype. Front Microbiol 2023; 13:982679. [PMID: 36687580 PMCID: PMC9850167 DOI: 10.3389/fmicb.2022.982679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 12/06/2022] [Indexed: 01/07/2023] Open
Abstract
Mycobacterium brumae is a rapid-growing, non-pathogenic Mycobacterium species, originally isolated from environmental and human samples in Barcelona, Spain. Mycobacterium brumae is not pathogenic and it's in vitro phenotype and immunogenic properties have been well characterized. However, the knowledge of its underlying genetic composition is still incomplete. In this study, we first describe the 4 Mb genome of the M. brumae type strain ATCC 51384T assembling PacBio reads, and second, we assess the low intraspecies variability by comparing the type strain with Illumina reads from three additional strains. Mycobacterium brumae genome is composed of a circular chromosome with a high GC content of 69.2% and containing 3,791 CDSs, 97 pseudogenes, one prophage and no CRISPR loci. Mycobacterium brumae has shown no pathogenic potential in in vivo experiments, and our genomic analysis confirms its phylogenetic position with other non-pathogenic and rapid growing mycobacteria. Accordingly, we determined the absence of virulence-related genes, such as ESX-1 locus and most PE/PPE genes, among others. Although the immunogenic potential of M. brumae was proved to be as high as Mycobacterium bovis BCG, the only mycobacteria licensed to treat cancer, the genomic content of M. tuberculosis T cell and B cell antigens in M. brumae genome is considerably lower than those antigens present in M. bovis BCG genome. Overall, this work provides relevant genomic data on one of the species of the mycobacterial genus with high therapeutic potential.
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Affiliation(s)
| | - Paula Herrero-Abadía
- Genetics and Microbiology Department, Faculty of Biosciences, Autonomous University of Barcelona, Barcelona, Spain
| | | | - Vicente Sentandreu
- Genomics Unit, Central Service for Experimental Research (SCSIE), University of Valencia, Burjassot, Spain
| | - Eduard Torrents
- Bacterial Infections and Antimicrobial Therapies Group, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain,Microbiology Section, Department of Genetics, Microbiology, and Statistics, Biology Faculty, Universitat de Barcelona, Barcelona, Spain
| | | | | | - Iñaki Comas
- Instituto de Biomedicina de Valencia (IBV), CSIC, Valencia, Spain
| | - Esther Julián
- Genetics and Microbiology Department, Faculty of Biosciences, Autonomous University of Barcelona, Barcelona, Spain,Esther Julián, ✉
| | - Mireia Coscolla
- I2SysBio, University of Valencia-FISABIO Joint Unit, Paterna, Spain,*Correspondence: Mireia Coscolla, ✉
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12
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Alteri CJ, Rios-Sarabia N, De la Cruz MA, González-y-Merchand JA, Soria-Bustos J, Maldonado-Bernal C, Cedillo ML, Yáñez-Santos JA, Martínez-Laguna Y, Torres J, Friedman RL, Girón JA, Ares MA. The Flp type IV pilus operon of Mycobacterium tuberculosis is expressed upon interaction with macrophages and alveolar epithelial cells. Front Cell Infect Microbiol 2022; 12:916247. [PMID: 36204636 PMCID: PMC9531140 DOI: 10.3389/fcimb.2022.916247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Accepted: 08/29/2022] [Indexed: 11/13/2022] Open
Abstract
The genome of Mycobacterium tuberculosis (Mtb) harbors the genetic machinery for assembly of the Fimbrial low-molecular-weight protein (Flp) type IV pilus. Presumably, the Flp pilus is essential for pathogenesis. However, it remains unclear whether the pili genes are transcribed in culture or during infection of host cells. This study aimed to shed light on the expression of the Flp pili-assembly genes (tadZ, tadA, tadB, tadC, flp, tadE, and tadF) in Mtb growing under different growth conditions (exponential phase, stationary phase, and dormancy NRP1 and NRP2 phases induced by hypoxia), during biofilm formation, and in contact with macrophages and alveolar epithelial cells. We found that expression of tad/flp genes was significantly higher in the stationary phase than in exponential or NRP1 or NRP2 phases suggesting that the bacteria do not require type IV pili during dormancy. Elevated gene expression levels were recorded when the bacilli were in contact for 4 h with macrophages or epithelial cells, compared to mycobacteria propagated alone in the cultured medium. An antibody raised against a 12-mer peptide derived from the Flp pilin subunit detected the presence of Flp pili on intra- and extracellular bacteria infecting eukaryotic cells. Altogether, these are compelling data showing that the Flp pili genes are expressed during the interaction of Mtb with host cells and highlight a role for Flp pili in colonization and invasion of the host, subsequently promoting bacterial survival during dormancy.
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Affiliation(s)
- Christopher J. Alteri
- Department of Natural Sciences, University of Michigan-Dearborn, Dearborn, MI, United States
| | - Nora Rios-Sarabia
- Unidad de Investigación Médica en Enfermedades Infecciosas y Parasitarias, Hospital de Pediatría, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, Mexico City, Mexico
| | - Miguel A. De la Cruz
- Unidad de Investigación Médica en Enfermedades Infecciosas y Parasitarias, Hospital de Pediatría, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, Mexico City, Mexico
| | - Jorge A. González-y-Merchand
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
| | - Jorge Soria-Bustos
- Instituto de Ciencias de la Salud, Universidad Autónoma del Estado de Hidalgo, Hidalgo, Mexico
| | - Carmen Maldonado-Bernal
- Laboratorio de Investigación en Inmunología y Proteómica, Hospital Infantil de México Federico Gómez, Mexico City, Mexico
| | - María L. Cedillo
- Centro de Detección Biomolecular, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
| | - Jorge A. Yáñez-Santos
- Centro de Detección Biomolecular, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
| | - Ygnacio Martínez-Laguna
- Centro de Investigación en Ciencias Microbiológicas, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
| | - Javier Torres
- Unidad de Investigación Médica en Enfermedades Infecciosas y Parasitarias, Hospital de Pediatría, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, Mexico City, Mexico
| | - Richard L. Friedman
- Department of Immunobiology, University of Arizona, Tucson, AZ, United States
| | - Jorge A. Girón
- Centro de Detección Biomolecular, Benemérita Universidad Autónoma de Puebla, Puebla, Mexico
- *Correspondence: Miguel A. Ares, ; Jorge A. Girón,
| | - Miguel A. Ares
- Unidad de Investigación Médica en Enfermedades Infecciosas y Parasitarias, Hospital de Pediatría, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, Mexico City, Mexico
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
- *Correspondence: Miguel A. Ares, ; Jorge A. Girón,
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13
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Boopathi S, Ramasamy S, Haridevamuthu B, Murugan R, Veerabadhran M, Jia AQ, Arockiaraj J. Intercellular communication and social behaviors in mycobacteria. Front Microbiol 2022; 13:943278. [PMID: 36177463 PMCID: PMC9514802 DOI: 10.3389/fmicb.2022.943278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 08/22/2022] [Indexed: 11/13/2022] Open
Abstract
Cell-to-cell communication is a fundamental process of bacteria to exert communal behaviors. Sputum samples of patients with cystic fibrosis have often been observed with extensive mycobacterial genetic diversity. The emergence of heterogenic mycobacterial populations is observed due to subtle changes in their morphology, gene expression level, and distributive conjugal transfer (DCT). Since each subgroup of mycobacteria has different hetero-resistance, they are refractory against several antibiotics. Such genetically diverse mycobacteria have to communicate with each other to subvert the host immune system. However, it is still a mystery how such heterogeneous strains exhibit synchronous behaviors for the production of quorum sensing (QS) traits, such as biofilms, siderophores, and virulence proteins. Mycobacteria are characterized by division of labor, where distinct sub-clonal populations contribute to the production of QS traits while exchanging complimentary products at the community level. Thus, active mycobacterial cells ensure the persistence of other heterogenic clonal populations through cooperative behaviors. Additionally, mycobacteria are likely to establish communication with neighboring cells in a contact-independent manner through QS signals. Hence, this review is intended to discuss our current knowledge of mycobacterial communication. Understanding mycobacterial communication could provide a promising opportunity to develop drugs to target key pathways of mycobacteria.
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Affiliation(s)
- Seenivasan Boopathi
- Key Laboratory of Tropical Biological Resources of Ministry Education, School of Pharmaceutical Sciences, Hainan University, Haikou, China
- Department of Biotechnology, College of Science and Humanities, SRM Institute of Science and Technology, Chennai, Tamil Nadu, India
| | - Subbiah Ramasamy
- Department of Biochemistry, Cardiac Metabolic Disease Laboratory, School of Biological Sciences, Madurai Kamaraj University, Madurai, India
| | - B. Haridevamuthu
- Department of Biotechnology, College of Science and Humanities, SRM Institute of Science and Technology, Chennai, Tamil Nadu, India
| | - Raghul Murugan
- Department of Biotechnology, College of Science and Humanities, SRM Institute of Science and Technology, Chennai, Tamil Nadu, India
| | - Maruthanayagam Veerabadhran
- Biofouling and Biofilm Processes Section, Water and Steam Chemistry Division, Bhabha Atomic Research Centre Facilities, Kalpakkam, Tamil Nadu, India
| | - Ai-Qun Jia
- Key Laboratory of Tropical Biological Resources of Ministry Education, School of Pharmaceutical Sciences, Hainan University, Haikou, China
- *Correspondence: Ai-Qun Jia
| | - Jesu Arockiaraj
- Department of Biotechnology, College of Science and Humanities, SRM Institute of Science and Technology, Chennai, Tamil Nadu, India
- Jesu Arockiaraj ;
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14
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Dordet-Frisoni E, Vandecasteele C, Contarin R, Sagné E, Baranowski E, Klopp C, Nouvel LX, Citti C. Impacts of Mycoplasma agalactiae restriction-modification systems on pan-epigenome dynamics and genome plasticity. Microb Genom 2022; 8. [PMID: 35576144 PMCID: PMC9465063 DOI: 10.1099/mgen.0.000829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
DNA methylations play an important role in the biology of bacteria. Often associated with restriction modification (RM) systems, they are important drivers of bacterial evolution interfering in horizontal gene transfer events by providing a defence against foreign DNA invasion or by favouring genetic transfer through production of recombinogenic DNA ends. Little is known regarding the methylome of the Mycoplasma genus, which encompasses several pathogenic species with small genomes. Here, genome-wide detection of DNA methylations was conducted using single molecule real-time (SMRT) and bisulphite sequencing in several strains of Mycoplasma agalactiae, an important ruminant pathogen and a model organism. Combined with whole-genome analysis, this allowed the identification of 19 methylated motifs associated with three orphan methyltransferases (MTases) and eight RM systems. All systems had a homolog in at least one phylogenetically distinct Mycoplasma spp. Our study also revealed that several superimposed genetic events may participate in the M. agalactiae dynamic epigenomic landscape. These included (i) DNA shuffling and frameshift mutations that affect the MTase and restriction endonuclease content of a clonal population and (ii) gene duplication, erosion, and horizontal transfer that modulate MTase and RM repertoires of the species. Some of these systems were experimentally shown to play a major role in mycoplasma conjugative, horizontal DNA transfer. While the versatility of DNA methylation may contribute to regulating essential biological functions at cell and population levels, RM systems may be key in mycoplasma genome evolution and adaptation by controlling horizontal gene transfers.
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Affiliation(s)
- Emilie Dordet-Frisoni
- IHAP, Université de Toulouse, INRAE, ENVT, Toulouse, France.,Present address: INTHERES, Université de Toulouse, INRAE, ENVT, Toulouse, France
| | | | | | - Eveline Sagné
- IHAP, Université de Toulouse, INRAE, ENVT, Toulouse, France
| | | | - Christophe Klopp
- INRAE, UR875 MIAT, Sigenae, BioInfo Genotoul, BioInfoMics, F-31326 Auzeville, France
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15
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Sabin S, Morales-Arce AY, Pfeifer SP, Jensen JD. The impact of frequently neglected model violations on bacterial recombination rate estimation: a case study in Mycobacterium canettii and Mycobacterium tuberculosis. G3 (BETHESDA, MD.) 2022; 12:jkac055. [PMID: 35253851 PMCID: PMC9073693 DOI: 10.1093/g3journal/jkac055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Accepted: 02/28/2022] [Indexed: 12/04/2022]
Abstract
Mycobacterium canettii is a causative agent of tuberculosis in humans, along with the members of the Mycobacterium tuberculosis complex. Frequently used as an outgroup to the M. tuberculosis complex in phylogenetic analyses, M. canettii is thought to offer the best proxy for the progenitor species that gave rise to the complex. Here, we leverage whole-genome sequencing data and biologically relevant population genomic models to compare the evolutionary dynamics driving variation in the recombining M. canettii with that in the nonrecombining M. tuberculosis complex, and discuss differences in observed genomic diversity in the light of expected levels of Hill-Robertson interference. In doing so, we highlight the methodological challenges of estimating recombination rates through traditional population genetic approaches using sequences called from populations of microorganisms and evaluate the likely mis-inference that arises owing to a neglect of common model violations including purifying selection, background selection, progeny skew, and population size change. In addition, we compare performance when full within-host polymorphism data are utilized, versus the more common approach of basing analyses on within-host consensus sequences.
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Affiliation(s)
- Susanna Sabin
- Center for Evolution and Medicine, School of Life Sciences, Arizona State University, Tempe, AZ 85281, USA
| | - Ana Y Morales-Arce
- Center for Evolution and Medicine, School of Life Sciences, Arizona State University, Tempe, AZ 85281, USA
| | - Susanne P Pfeifer
- Center for Evolution and Medicine, School of Life Sciences, Arizona State University, Tempe, AZ 85281, USA
| | - Jeffrey D Jensen
- Center for Evolution and Medicine, School of Life Sciences, Arizona State University, Tempe, AZ 85281, USA
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16
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Morgado S, Vicente AC. Conjugative transfer of naturally occurring plasmid in Mycolicibacterium sp. FEMS Microbiol Lett 2022; 369:6554244. [PMID: 35333321 DOI: 10.1093/femsle/fnac035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 02/16/2022] [Accepted: 03/23/2022] [Indexed: 11/14/2022] Open
Abstract
Conjugation is considered the main horizontal gene transfer (HGT) mechanism in bacterial adaptation and evolution. In the Mycobacteriaceae family, Mycolicibacterium smegmatis has been used as the model organism for the conjugative transfer of hybrid plasmids. However, the natural conjugation process in any bacteria would involve the transfer of naturally occurring plasmids. Currently, there is a gap in this regard about this abundant environmental genus of Mycobacteriaceae. Here, we performed conjugation experiments between wild Mycolicibacterium sp. strains involving naturally occurring plasmids, and interestingly, evidence of conjugative transfer was obtained. Thus, it is likely that conjugation occurs in Mycolicibacterium in the natural environment, representing a source of diversification and evolution in this genus of bacteria.
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Affiliation(s)
- Sergio Morgado
- Laboratory of Molecular Genetics of Microorganisms, Institute Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Ana Carolina Vicente
- Laboratory of Molecular Genetics of Microorganisms, Institute Oswaldo Cruz, Rio de Janeiro, Brazil
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17
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A Polymorphic Gene within the Mycobacterium smegmatis esx1 Locus Determines Mycobacterial Self-Identity and Conjugal Compatibility. mBio 2022; 13:e0021322. [PMID: 35297678 PMCID: PMC9040860 DOI: 10.1128/mbio.00213-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Mycobacteria mediate horizontal gene transfer (HGT) by a process called distributive conjugal transfer (DCT) that is mechanistically distinct from oriT-mediated plasmid transfer. The transfer of multiple, independent donor chromosome segments generates transconjugants with genomes that are mosaic blends of their parents. Previously, we had characterized contact-dependent conjugation between two independent isolates of Mycobacterium smegmatis. Here, we expand our analyses to include five independent isolates of M. smegmatis and establish that DCT is both active and prevalent among natural isolates of M. smegmatis. Two of these five strains were recipients but exhibited distinct conjugal compatibilities with donor strains, suggesting an ability to distinguish between potential donor partners. We determined that a single gene, Msmeg0070, was responsible for conferring mating compatibility using a combination of comparative DNA sequence analysis, bacterial genome-wide association studies (GWAS), and targeted mutagenesis. Msmeg0070 maps within the esx1 secretion locus, and we establish that it confers mycobacterial self-identity with parallels to kin recognition. Similar to other kin model systems, orthologs of Msmeg0070 are highly polymorphic. The identification of a kin recognition system in M. smegmatis reinforces the concept that communication between cells is an important checkpoint prior to DCT commitment and implies that there are likely to be other, unanticipated forms of social behaviors in mycobacteria. IMPORTANCE Conjugation, unlike other forms of HGT, requires direct interaction between two viable bacteria, which must be capable of distinguishing between mating types to allow successful DNA transfer from donor to recipient. We show that the conjugal compatibility of Mycobacterium smegmatis isolates is determined by a single, polymorphic gene located within the conserved esx1 secretion locus. This gene confers self-identity; the expression of identical Msmeg0070 proteins in both donor-recipient partners prevents DNA transfer. The presence of this polymorphic locus in many environmental mycobacteria suggests that kin identification is important in promoting beneficial gene flow between nonkin mycobacteria. Cell-cell communication, mediated by kin recognition and ESX secretion, is a key checkpoint in mycobacterial conjugation and likely plays a more global role in mycobacterial biology.
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18
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Vasileva D, Streich J, Burdick L, Klingeman D, Chhetri HB, Brelsford C, Ellis JC, Close DM, Jacobson D, Michener J. Protoplast fusion in Bacillus species produces frequent, unbiased, genome-wide homologous recombination. Nucleic Acids Res 2022; 50:6211-6223. [PMID: 35061904 PMCID: PMC9226520 DOI: 10.1093/nar/gkac025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 01/05/2022] [Accepted: 01/07/2022] [Indexed: 01/09/2023] Open
Abstract
In eukaryotes, fine-scale maps of meiotic recombination events have greatly advanced our understanding of the factors that affect genomic variation patterns and evolution of traits. However, in bacteria that lack natural systems for sexual reproduction, unbiased characterization of recombination landscapes has remained challenging due to variable rates of genetic exchange and influence of natural selection. Here, to overcome these limitations and to gain a genome-wide view on recombination, we crossed Bacillus strains with different genetic distances using protoplast fusion. The offspring displayed complex inheritance patterns with one of the parents consistently contributing the major part of the chromosome backbone and multiple unselected fragments originating from the second parent. Our results demonstrate that this bias was in part due to the action of restriction-modification systems, whereas genome features like GC content and local nucleotide identity did not affect distribution of recombination events around the chromosome. Furthermore, we found that recombination occurred uniformly across the genome without concentration into hotspots. Notably, our results show that species-level genetic distance did not affect genome-wide recombination. This study provides a new insight into the dynamics of recombination in bacteria and a platform for studying recombination patterns in diverse bacterial species.
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Affiliation(s)
| | | | | | - Dawn M Klingeman
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA
| | - Hari B Chhetri
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA,Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA
| | - Christa M Brelsford
- Geospatial Science and Human Security Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA
| | - J Christopher Ellis
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA,Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA
| | - Dan M Close
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA
| | - Daniel A Jacobson
- Correspondence may also be addressed to Daniel A. Jacobson. Tel: +1 865 574 6134; Fax: +1 865 241 2869;
| | - Joshua K Michener
- To whom correspondence should be addressed. Tel: +1 865 576 7957; Fax: +1 865 576 8646;
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19
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Bohr LL, Youngblom MA, Eldholm V, Pepperell CS. Genome reorganization during emergence of host-associated Mycobacterium abscessus. Microb Genom 2021; 7. [PMID: 34874249 PMCID: PMC8767326 DOI: 10.1099/mgen.0.000706] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Mycobacterium abscessus is a rapid growing, free-living species of bacterium that also causes lung infections in humans. Human infections are usually acquired from the environment; however, dominant circulating clones (DCCs) have emerged recently in both M. abscessus subsp. massiliense and subsp. abscessus that appear to be transmitted among humans and are now globally distributed. These recently emerged clones are potentially informative about the ecological and evolutionary mechanisms of pathogen emergence and host adaptation. The geographical distribution of DCCs has been reported, but the genomic processes underlying their transition from environmental bacterium to human pathogen are not well characterized. To address this knowledge gap, we delineated the structure of M. abscessus subspecies abscessus and massiliense using genomic data from 200 clinical isolates of M. abscessus from seven geographical regions. We identified differences in overall patterns of lateral gene transfer (LGT) and barriers to LGT between subspecies and between environmental and host-adapted bacteria. We further characterized genome reorganization that accompanied bacterial host adaptation, inferring selection pressures acting at both genic and intergenic loci. We found that both subspecies encode an expansive pangenome with many genes at rare frequencies. Recombination appears more frequent in M. abscessus subsp. massiliense than in subsp. abscessus, consistent with prior reports. We found evidence suggesting that phage are exchanged between subspecies, despite genetic barriers evident elsewhere throughout the genome. Patterns of LGT differed according to niche, with less LGT observed among host-adapted DCCs versus environmental bacteria. We also found evidence suggesting that DCCs are under distinct selection pressures at both genic and intergenic sites. Our results indicate that host adaptation of M. abscessus was accompanied by major changes in genome evolution, including shifts in the apparent frequency of LGT and impacts of selection. Differences were evident among the DCCs as well, which varied in the degree of gene content remodelling, suggesting they were placed differently along the evolutionary trajectory toward host adaptation. These results provide insight into the evolutionary forces that reshape bacterial genomes as they emerge into the pathogenic niche.
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Affiliation(s)
- Lindsey L Bohr
- Department of Medical Microbiology and Immunology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - Madison A Youngblom
- Department of Medical Microbiology and Immunology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | | | - Caitlin S Pepperell
- Department of Medical Microbiology and Immunology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA.,Department of Medicine, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
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20
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Pajuelo D, Tak U, Zhang L, Danilchanka O, Tischler AD, Niederweis M. Toxin secretion and trafficking by Mycobacterium tuberculosis. Nat Commun 2021; 12:6592. [PMID: 34782620 PMCID: PMC8593097 DOI: 10.1038/s41467-021-26925-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 10/27/2021] [Indexed: 12/30/2022] Open
Abstract
The tuberculosis necrotizing toxin (TNT) is the major cytotoxicity factor of Mycobacterium tuberculosis (Mtb) in macrophages. TNT is the C-terminal domain of the outer membrane protein CpnT and gains access to the cytosol to kill macrophages infected with Mtb. However, molecular mechanisms of TNT secretion and trafficking are largely unknown. A comprehensive analysis of the five type VII secretion systems of Mtb revealed that the ESX-4 system is required for export of CpnT and surface accessibility of TNT. Furthermore, the ESX-2 and ESX-4 systems are required for permeabilization of the phagosomal membrane in addition to the ESX-1 system. Thus, these three ESX systems need to act in concert to enable trafficking of TNT into the cytosol of Mtb-infected macrophages. These discoveries establish new molecular roles for the two previously uncharacterized type VII secretion systems ESX-2 and ESX-4 and reveal an intricate link between toxin secretion and phagosomal permeabilization by Mtb. The tuberculosis necrotizing toxin (TNT) is the major cytotoxicity factor of M. tuberculosis (Mtb). Mtb possesses five type VII secretion systems (ESX). Pajuelo et al. show that the ESX-4 system is required for TNT secretion and that ESX-2 and ESX-4 systems work in concert with ESX-1 to permeabilize the phagosomal membrane and enable trafficking of TNT into the cytoplasm of macrophages infected with Mtb.
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Affiliation(s)
- David Pajuelo
- Department of Microbiology, University of Alabama at Birmingham, 609 Bevill Biomedical Research Building, 845 19th Street South, Birmingham, AL, 35294, USA
| | - Uday Tak
- Department of Microbiology, University of Alabama at Birmingham, 609 Bevill Biomedical Research Building, 845 19th Street South, Birmingham, AL, 35294, USA.,University of Colorado Boulder, Jennie Smoly Caruthers Biotechnology Building B255, 3415 Colorado Avenue, Boulder, CO, 80303, USA
| | - Lei Zhang
- Department of Microbiology, University of Alabama at Birmingham, 609 Bevill Biomedical Research Building, 845 19th Street South, Birmingham, AL, 35294, USA
| | - Olga Danilchanka
- Department of Microbiology, University of Alabama at Birmingham, 609 Bevill Biomedical Research Building, 845 19th Street South, Birmingham, AL, 35294, USA.,Merck & Co., Inc., Cambridge, MA, 02141, USA
| | - Anna D Tischler
- Department of Microbiology and Immunology, University of Minnesota Twin Cities, Minneapolis, MN, 55455, USA
| | - Michael Niederweis
- Department of Microbiology, University of Alabama at Birmingham, 609 Bevill Biomedical Research Building, 845 19th Street South, Birmingham, AL, 35294, USA.
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21
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Rivera-Calzada A, Famelis N, Llorca O, Geibel S. Type VII secretion systems: structure, functions and transport models. Nat Rev Microbiol 2021; 19:567-584. [PMID: 34040228 DOI: 10.1038/s41579-021-00560-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/09/2021] [Indexed: 02/07/2023]
Abstract
Type VII secretion systems (T7SSs) have a key role in the secretion of effector proteins in non-pathogenic mycobacteria and pathogenic mycobacteria such as Mycobacterium tuberculosis, the main causative agent of tuberculosis. Tuberculosis-causing mycobacteria, still accounting for 1.4 million deaths annually, rely on paralogous T7SSs to survive in the host and efficiently evade its immune response. Although it is still unknown how effector proteins of T7SSs cross the outer membrane of the diderm mycobacterial cell envelope, recent advances in the structural characterization of these secretion systems have revealed the intricate network of interactions of conserved components in the plasma membrane. This structural information, added to recent advances in the molecular biology and regulation of mycobacterial T7SSs as well as progress in our understanding of their secreted effector proteins, is shedding light on the inner working of the T7SS machinery. In this Review, we highlight the implications of these studies and the derived transport models, which provide new scenarios for targeting the deathly human pathogen M. tuberculosis.
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Affiliation(s)
- Angel Rivera-Calzada
- Structural Biology Programme, Spanish National Cancer Research Centre (CNIO), Madrid, Spain.
| | - Nikolaos Famelis
- Institute for Molecular Infection Biology, Julius-Maximilian University of Würzburg, Würzburg, Germany.,Rudolf Virchow Center for Integrative and Translational Biomedicine, Julius-Maximilian University of Würzburg, Würzburg, Germany
| | - Oscar Llorca
- Structural Biology Programme, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Sebastian Geibel
- Institute for Molecular Infection Biology, Julius-Maximilian University of Würzburg, Würzburg, Germany. .,Rudolf Virchow Center for Integrative and Translational Biomedicine, Julius-Maximilian University of Würzburg, Würzburg, Germany.
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22
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Lagune M, Petit C, Sotomayor FV, Johansen MD, Beckham KSH, Ritter C, Girard-Misguich F, Wilmanns M, Kremer L, Maurer FP, Herrmann JL. Conserved and specialized functions of Type VII secretion systems in non-tuberculous mycobacteria. MICROBIOLOGY-SGM 2021; 167. [PMID: 34224347 DOI: 10.1099/mic.0.001054] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Non-tuberculous mycobacteria (NTM) are a large group of micro-organisms comprising more than 200 individual species. Most NTM are saprophytic organisms and are found mainly in terrestrial and aquatic environments. In recent years, NTM have been increasingly associated with infections in both immunocompetent and immunocompromised individuals, prompting significant efforts to understand the diverse pathogenic and signalling traits of these emerging pathogens. Since the discovery of Type VII secretion systems (T7SS), there have been significant developments regarding the role of these complex systems in mycobacteria. These specialised systems, also known as Early Antigenic Secretion (ESX) systems, are employed to secrete proteins across the inner membrane. They also play an essential role in virulence, nutrient uptake and conjugation. Our understanding of T7SS in mycobacteria has significantly benefited over the last few years, from the resolution of ESX-3 structure in Mycobacterium smegmatis, to ESX-5 structures in Mycobacterium xenopi and Mycobacterium tuberculosis. In addition, ESX-4, considered until recently as a non-functional system in both pathogenic and non-pathogenic mycobacteria, has been proposed to play an important role in the virulence of Mycobacterium abscessus; an increasingly recognized opportunistic NTM causing severe lung diseases. These major findings have led to important new insights into the functional mechanisms of these biological systems, their implication in virulence, nutrient acquisitions and cell wall shaping, and will be discussed in this review.
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Affiliation(s)
- Marion Lagune
- Université Paris-Saclay, UVSQ, Inserm, Infection et inflammation, 78180, Montigny-Le-Bretonneux, France
| | - Cecile Petit
- European Molecular Biology Laboratory, Hamburg Unit, Notkestraße 85, 22607 Hamburg, Germany
| | - Flor Vásquez Sotomayor
- National and WHO Supranational Reference Center for Mycobacteria, Research Center Borstel, Leibniz Lung Center, Borstel, Germany
| | - Matt D Johansen
- Centre National de la Recherche Scientifique UMR 9004, Institut de Recherche en Infectiologie de Montpellier (IRIM), Université de Montpellier, 1919 route de Mende, 34293, Montpellier, France.,Present address: Centre for Inflammation, Centenary Institute and University of Technology Sydney, Faculty of Science, Sydney, NSW, Australia
| | - Kathrine S H Beckham
- European Molecular Biology Laboratory, Hamburg Unit, Notkestraße 85, 22607 Hamburg, Germany
| | - Christina Ritter
- European Molecular Biology Laboratory, Hamburg Unit, Notkestraße 85, 22607 Hamburg, Germany
| | - Fabienne Girard-Misguich
- Université Paris-Saclay, UVSQ, Inserm, Infection et inflammation, 78180, Montigny-Le-Bretonneux, France
| | - Matthias Wilmanns
- European Molecular Biology Laboratory, Hamburg Unit, Notkestraße 85, 22607 Hamburg, Germany.,University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20251 Hamburg, Germany
| | - Laurent Kremer
- Centre National de la Recherche Scientifique UMR 9004, Institut de Recherche en Infectiologie de Montpellier (IRIM), Université de Montpellier, 1919 route de Mende, 34293, Montpellier, France.,INSERM, IRIM, 34293 Montpellier, France
| | - Florian P Maurer
- National and WHO Supranational Reference Center for Mycobacteria, Research Center Borstel, Leibniz Lung Center, Borstel, Germany.,Institute of Medical Microbiology, Virology and Hospital Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jean-Louis Herrmann
- Université Paris-Saclay, UVSQ, Inserm, Infection et inflammation, 78180, Montigny-Le-Bretonneux, France.,APHP, GHU Paris-Saclay, Hôpital Raymond Poincaré, Service de Microbiologie, Garches, France
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23
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Khare T, Anand U, Dey A, Assaraf YG, Chen ZS, Liu Z, Kumar V. Exploring Phytochemicals for Combating Antibiotic Resistance in Microbial Pathogens. Front Pharmacol 2021; 12:720726. [PMID: 34366872 PMCID: PMC8334005 DOI: 10.3389/fphar.2021.720726] [Citation(s) in RCA: 69] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 06/28/2021] [Indexed: 01/09/2023] Open
Abstract
Antibiotic resistance or microbial drug resistance is emerging as a serious threat to human healthcare globally, and the multidrug-resistant (MDR) strains are imposing major hurdles to the progression of drug discovery programs. Newer antibiotic-resistance mechanisms in microbes contribute to the inefficacy of the existing drugs along with the prolonged illness and escalating expenditures. The injudicious usage of the conventional and commonly available antibiotics in human health, hygiene, veterinary and agricultural practices is proving to be a major driver for evolution, persistence and spread of antibiotic-resistance at a frightening rate. The drying pipeline of new and potent antibiotics is adding to the severity. Therefore, novel and effective new drugs and innovative therapies to treat MDR infections are urgently needed. Apart from the different natural and synthetic drugs being tested, plant secondary metabolites or phytochemicals are proving efficient in combating the drug-resistant strains. Various phytochemicals from classes including alkaloids, phenols, coumarins, terpenes have been successfully demonstrated their inhibitory potential against the drug-resistant pathogens. Several phytochemicals have proved effective against the molecular determinants responsible for attaining the drug resistance in pathogens like membrane proteins, biofilms, efflux pumps and bacterial cell communications. However, translational success rate needs to be improved, but the trends are encouraging. This review highlights current knowledge and developments associated challenges and future prospects for the successful application of phytochemicals in combating antibiotic resistance and the resistant microbial pathogens.
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Affiliation(s)
- Tushar Khare
- Department of Biotechnology, Modern College of Arts, Science and Commerce (Savitribai Phule Pune University), Pune, India.,Department of Environmental Science, Savitribai Phule Pune University, Pune, India
| | - Uttpal Anand
- Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Abhijit Dey
- Ethnopharmacology and Natural Product Research Laboratory, Department of Life Sciences, Presidency University, Kolkata, India
| | - Yehuda G Assaraf
- The Fred Wyszkowski Cancer Research Laboratory, Department of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | - Zhe-Sheng Chen
- Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, St. John's University, Queens, NY, United States
| | - Zhijun Liu
- Department of Microbiology, Weifang Medical University, Weifang, China
| | - Vinay Kumar
- Department of Biotechnology, Modern College of Arts, Science and Commerce (Savitribai Phule Pune University), Pune, India.,Department of Environmental Science, Savitribai Phule Pune University, Pune, India
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24
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Morgado SM, Paulo Vicente AC. Genomics of Atlantic Forest Mycobacteriaceae strains unravels a mobilome diversity with a novel integrative conjugative element and plasmids harbouring T7SS. Microb Genom 2021; 6. [PMID: 32496186 PMCID: PMC7478629 DOI: 10.1099/mgen.0.000382] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Mobile genetic elements (MGEs) are agents of bacterial evolution and adaptation. Genome sequencing provides an unbiased approach that has revealed an abundance of MGEs in prokaryotes, mainly plasmids and integrative conjugative elements. Nevertheless, many mobilomes, particularly those from environmental bacteria, remain underexplored despite their representing a reservoir of genes that can later emerge in the clinic. Here, we explored the mobilome of the Mycobacteriaceae family, focusing on strains from Brazilian Atlantic Forest soil. Novel Mycolicibacterium and Mycobacteroides strains were identified, with the former ones harbouring linear and circular plasmids encoding the specialized type-VII secretion system (T7SS) and mobility-associated genes. In addition, we also identified a T4SS-mediated integrative conjugative element (ICEMyc226) encoding two T7SSs and a number of xenobiotic degrading genes. Our study uncovers the diversity of the Mycobacteriaceae mobilome, providing the evidence of an ICE in this bacterial family. Moreover, the presence of T7SS genes in an ICE, as well as plasmids, highlights the role of these mobile genetic elements in the dispersion of T7SS.
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25
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Abstract
Current models of horizontal gene transfer (HGT) in mycobacteria are based on “distributive conjugal transfer” (DCT), an HGT type described in the fast-growing, saprophytic model organism Mycobacterium smegmatis, which creates genome mosaicism in resulting strains and depends on an ESX-1 type VII secretion system. In contrast, only few data on interstrain DNA transfer are available for tuberculosis-causing mycobacteria, for which chromosomal DNA transfer between two Mycobacterium canettii strains was reported, a process which, however, was not observed for Mycobacterium tuberculosis strains. Here, we have studied a wide range of human- and animal-adapted members of the Mycobacterium tuberculosis complex (MTBC) using an optimized filter-based mating assay together with three selected strains of M. canettii that acted as DNA recipients. Unlike in previous approaches, we obtained a high yield of thousands of recombinants containing transferred chromosomal DNA fragments from various MTBC donor strains, as confirmed by whole-genome sequence analysis of 38 randomly selected clones. While the genome organizations of the obtained recombinants showed mosaicisms of donor DNA fragments randomly integrated into a recipient genome backbone, reminiscent of those described as being the result of ESX-1-mediated DCT in M. smegmatis, we observed similar transfer efficiencies when ESX-1-deficient donor and/or recipient mutants were used, arguing that in tubercle bacilli, HGT is an ESX-1-independent process. These findings provide new insights into the genetic events driving the pathoevolution of M. tuberculosis and radically change our perception of HGT in mycobacteria, particularly for those species that show recombinogenic population structures despite the natural absence of ESX-1 secretion systems.
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26
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Luo T, Xu P, Zhang Y, Porter JL, Ghanem M, Liu Q, Jiang Y, Li J, Miao Q, Hu B, Howden BP, Fyfe JAM, Globan M, He W, He P, Wang Y, Liu H, Takiff HE, Zhao Y, Chen X, Pan Q, Behr MA, Stinear TP, Gao Q. Population genomics provides insights into the evolution and adaptation to humans of the waterborne pathogen Mycobacterium kansasii. Nat Commun 2021; 12:2491. [PMID: 33941780 PMCID: PMC8093194 DOI: 10.1038/s41467-021-22760-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 03/16/2021] [Indexed: 02/02/2023] Open
Abstract
Mycobacterium kansasii can cause serious pulmonary disease. It belongs to a group of closely-related species of non-tuberculous mycobacteria known as the M. kansasii complex (MKC). Here, we report a population genomics analysis of 358 MKC isolates from worldwide water and clinical sources. We find that recombination, likely mediated by distributive conjugative transfer, has contributed to speciation and on-going diversification of the MKC. Our analyses support municipal water as a main source of MKC infections. Furthermore, nearly 80% of the MKC infections are due to closely-related M. kansasii strains, forming a main cluster that apparently originated in the 1900s and subsequently expanded globally. Bioinformatic analyses indicate that several genes involved in metabolism (e.g., maintenance of the methylcitrate cycle), ESX-I secretion, metal ion homeostasis and cell surface remodelling may have contributed to M. kansasii's success and its ongoing adaptation to the human host.
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Affiliation(s)
- Tao Luo
- grid.13291.380000 0001 0807 1581Department of Pathogen Biology, West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, Chengdu, China ,grid.8547.e0000 0001 0125 2443Shanghai Institute of Infectious Disease and Biosecurity, Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Shanghai Medical College and School of Basic Medical Sciences, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Peng Xu
- grid.8547.e0000 0001 0125 2443Shanghai Institute of Infectious Disease and Biosecurity, Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Shanghai Medical College and School of Basic Medical Sciences, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China ,grid.417409.f0000 0001 0240 6969Key Laboratory of Characteristic Infectious Disease & Bio-safety Development of Guizhou Province Education Department, Institute of Life Sciences, Zunyi Medical University, Zunyi, China
| | - Yangyi Zhang
- Department of Tuberculosis Control, Shanghai Municipal Centre for Disease Control and Prevention, Shanghai, China
| | - Jessica L. Porter
- grid.1008.90000 0001 2179 088XDepartment of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Vic Australia ,grid.1008.90000 0001 2179 088XDoherty Applied Microbial Genomics, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Vic Australia
| | - Marwan Ghanem
- grid.14709.3b0000 0004 1936 8649Department of Microbiology and Immunology, McGill University and McGill International TB Centre, Montreal, Quebec Canada
| | - Qingyun Liu
- grid.8547.e0000 0001 0125 2443Shanghai Institute of Infectious Disease and Biosecurity, Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Shanghai Medical College and School of Basic Medical Sciences, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Yuan Jiang
- Department of Tuberculosis Control, Shanghai Municipal Centre for Disease Control and Prevention, Shanghai, China
| | - Jing Li
- Department of Tuberculosis Control, Shanghai Municipal Centre for Disease Control and Prevention, Shanghai, China
| | - Qing Miao
- grid.8547.e0000 0001 0125 2443Department of Infectious Diseases, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Bijie Hu
- grid.8547.e0000 0001 0125 2443Department of Infectious Diseases, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Benjamin P. Howden
- grid.1008.90000 0001 2179 088XDepartment of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Vic Australia ,grid.1008.90000 0001 2179 088XDoherty Applied Microbial Genomics, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Vic Australia ,grid.1008.90000 0001 2179 088XMicrobiological Diagnostic Unit Public Health Laboratory, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria 3000 Australia
| | - Janet A. M. Fyfe
- grid.429299.d0000 0004 0452 651XVictorian Infectious Diseases Reference Laboratory, Doherty Institute for Infection and Immunity, Melbourne Health, Melbourne, Vic Australia
| | - Maria Globan
- grid.429299.d0000 0004 0452 651XVictorian Infectious Diseases Reference Laboratory, Doherty Institute for Infection and Immunity, Melbourne Health, Melbourne, Vic Australia
| | - Wencong He
- grid.198530.60000 0000 8803 2373Chinese Center for Disease Control and Prevention and Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China
| | - Ping He
- grid.198530.60000 0000 8803 2373Chinese Center for Disease Control and Prevention and Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China
| | - Yiting Wang
- grid.198530.60000 0000 8803 2373Chinese Center for Disease Control and Prevention and Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China
| | - Houming Liu
- grid.263817.9Department of Clinical Laboratory, The Third People’s Hospital of Shenzhen, Southern University of Science and Technology, Shenzhen, China
| | - Howard E. Takiff
- grid.428999.70000 0001 2353 6535Unité de Pathogenetique Integrée Mycobacterienne, Institut Pasteur, Paris, France ,grid.418243.80000 0001 2181 3287Laboratorio de Genética Molecular, CMBC, IVIC, Caracas, Venezuela ,Shenzhen Nanshan Center for Chronic Disease Control, Shenzhen, China
| | - Yanlin Zhao
- grid.198530.60000 0000 8803 2373Chinese Center for Disease Control and Prevention and Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China
| | - Xinchun Chen
- grid.263488.30000 0001 0472 9649Guangdong Provincial Key Laboratory of Regional Immunity and Diseases, Department of Pathogen Biology, Shenzhen University School of Medicine, Shenzhen, China
| | - Qichao Pan
- Department of Tuberculosis Control, Shanghai Municipal Centre for Disease Control and Prevention, Shanghai, China
| | - Marcel A. Behr
- grid.14709.3b0000 0004 1936 8649Department of Microbiology and Immunology, McGill University and McGill International TB Centre, Montreal, Quebec Canada
| | - Timothy P. Stinear
- grid.1008.90000 0001 2179 088XDepartment of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Vic Australia ,grid.1008.90000 0001 2179 088XDoherty Applied Microbial Genomics, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Vic Australia
| | - Qian Gao
- grid.8547.e0000 0001 0125 2443Shanghai Institute of Infectious Disease and Biosecurity, Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Shanghai Medical College and School of Basic Medical Sciences, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
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27
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Abstract
Mycobacterium abscessus is an emerging pathogen that is often refractory to antibiotic control. Treatment is further complicated by considerable variation among clinical isolates in both their genetic constitution and their clinical manifestations. Here, we show that the prophage and plasmid mobilome is a likely contributor to this variation. Prophages and plasmids are common, abundant, and highly diverse, and code for large repertoires of genes influencing virulence, antibiotic susceptibility, and defense against viral infection. At least 85% of the strains we describe carry one or more prophages, representing at least 17 distinct and diverse sequence "clusters," integrated at 18 different attB locations. The prophages code for 19 distinct configurations of polymorphic toxin and toxin-immunity systems, each with WXG-100 motifs for export through type VII secretion systems. These are located adjacent to attachment junctions, are lysogenically expressed, and are implicated in promoting growth in infected host cells. Although the plethora of prophages and plasmids confounds the understanding of M. abscessus pathogenicity, they also provide an abundance of tools for M. abscessus engineering.IMPORTANCE Mycobacterium abscessus is an important emerging pathogen that is challenging to treat with current antibiotic regimens. There is substantial genomic variation in M. abscessus clinical isolates, but little is known about how this influences pathogenicity and in vivo growth. Much of the genomic variation is likely due to the large and varied mobilome, especially a large and diverse array of prophages and plasmids. The prophages are unrelated to previously characterized phages of mycobacteria and code for a diverse array of genes implicated in both viral defense and in vivo growth. Prophage-encoded polymorphic toxin proteins secreted via the type VII secretion system are common and highly varied and likely contribute to strain-specific pathogenesis.
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28
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Morgado SM, Vicente ACP. Comprehensive in silico survey of the Mycolicibacterium mobilome reveals an as yet underexplored diversity. Microb Genom 2021; 7:mgen000533. [PMID: 33620305 PMCID: PMC8190616 DOI: 10.1099/mgen.0.000533] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 01/28/2021] [Indexed: 11/30/2022] Open
Abstract
The mobilome plays a crucial role in bacterial adaptation and is therefore a starting point to understand and establish the gene flow occurring in the process of bacterial evolution. This is even more so if we consider that the mobilome of environmental bacteria can be the reservoir of genes that may later appear in the clinic. Recently, new genera have been proposed in the family Mycobacteriaceae, including the genus Mycolicibacterium, which encompasses dozens of species of agricultural, biotechnological, clinical and ecological importance, being ubiquitous in several environments. The current scenario in the Mycobacteriaceae mobilome has some bias because most of the characterized mycobacteriophages were isolated using a single host strain, and the few plasmids reported mainly relate to the genus Mycobacterium. To fill in the gaps in these issues, we performed a systematic in silico study of these mobile elements based on 242 available genomes of the genus Mycolicibacterium. The analyses identified 156 putative plasmids (19 conjugative, 45 mobilizable and 92 non-mobilizable) and 566 prophages in 86 and 229 genomes, respectively. Moreover, a contig was characterized by resembling an actinomycete integrative and conjugative element (AICE). Within this diversity of mobile genetic elements, there is a pool of genes associated with several canonical functions, in addition to adaptive traits, such as virulence and resistance to antibiotics and metals (mercury and arsenic). The type-VII secretion system was a common feature in the predicted plasmids, being associated with genes encoding virulent proteins (EsxA, EsxB, PE and PPE). In addition to the characterization of plasmids and prophages of the family Mycobacteriaceae, this study showed an abundance of these genetic elements in a dozen species of the genus Mycolicibacterium.
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29
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Pathogenic Determinants of the Mycobacterium kansasii Complex: An Unsuspected Role for Distributive Conjugal Transfer. Microorganisms 2021; 9:microorganisms9020348. [PMID: 33578772 PMCID: PMC7916490 DOI: 10.3390/microorganisms9020348] [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: 01/14/2021] [Revised: 02/02/2021] [Accepted: 02/05/2021] [Indexed: 01/15/2023] Open
Abstract
The Mycobacterium kansasii species comprises six subtypes that were recently classified into six closely related species; Mycobacterium kansasii (formerly M. kansasii subtype 1), Mycobacterium persicum (subtype 2), Mycobacterium pseudokansasii (subtype 3), Mycobacterium ostraviense (subtype 4), Mycobacterium innocens (subtype 5) and Mycobacterium attenuatum (subtype 6). Together with Mycobacterium gastri, they form the M. kansasii complex. M. kansasii is the most frequent and most pathogenic species of the complex. M. persicum is classically associated with diseases in immunosuppressed patients, and the other species are mostly colonizers, and are only very rarely reported in ill patients. Comparative genomics was used to assess the genetic determinants leading to the pathogenicity of members of the M. kansasii complex. The genomes of 51 isolates collected from patients with and without disease were sequenced and compared with 24 publicly available genomes. The pathogenicity of each isolate was determined based on the clinical records or public metadata. A comparative genomic analysis showed that all M. persicum, M. ostraviense, M innocens and M. gastri isolates lacked the ESX-1-associated EspACD locus that is thought to play a crucial role in the pathogenicity of M. tuberculosis and other non-tuberculous mycobacteria. Furthermore, M. kansasii was the only species exhibiting a 25-Kb-large genomic island encoding for 17 type-VII secretion system-associated proteins. Finally, a genome-wide association analysis revealed that two consecutive genes encoding a hemerythrin-like protein and a nitroreductase-like protein were significantly associated with pathogenicity. These two genes may be involved in the resistance to reactive oxygen and nitrogen species, a required mechanism for the intracellular survival of bacteria. Three non-pathogenic M. kansasii lacked these genes likely due to two distinct distributive conjugal transfers (DCTs) between M. attenuatum and M. kansasii, and one DCT between M. persicum and M. kansasii. To our knowledge, this is the first study linking DCT to reduced pathogenicity.
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30
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Blesa A, Baquedano I, González-de la Fuente S, Mencía M, Berenguer J. Integrative and Conjugative Element ICETh1 Functions as a Pangenomic DNA Capture Module in Thermus thermophilus. Microorganisms 2020; 8:microorganisms8122051. [PMID: 33371442 PMCID: PMC7767461 DOI: 10.3390/microorganisms8122051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 12/18/2020] [Accepted: 12/18/2020] [Indexed: 11/16/2022] Open
Abstract
Transjugation is an unconventional conjugation mechanism in Thermus thermophilus (Tth) that involves the active participation of both mating partners, encompassing a DNA secretion system (DSS) in the donor and an active natural competence apparatus (NCA) in the recipient cells. DSS is encoded within an integrative and conjugative element (ICETh1) in the strain Tth HB27, whereas the NCA is constitutively expressed in both mates. Previous experiments suggested the presence of multiple origins of transfer along the genome, which could generate genomic mosaicity among the progeny. Here, we designed transjugation experiments between two closely related strains of Tth with highly syntenic genomes, containing enough single nucleotide polymorphisms to allow precise parenthood analysis. Individual clones from the progeny were sequenced, revealing their origin as derivatives of our ICETh1-containing intended “donor” strain (HB27), which had acquired separate fragments from the genome of the ICETh1-free HB8 cells, which are our intended recipient. Due to the bidirectional nature of transjugation, only assays employing competence-defective HB27 derivatives as donors allowed the recovery of HB8-derived progeny. These results show a preference for a retrotransfer mechanism in transjugation in ICETh1-bearing strains, supporting an inter-strain gene-capture function for ICETh1. This function could benefit the donor-capable host by facilitating the acquisition of adaptive traits from external sources, ultimately increasing the open pangenome of Thermus, maximizing the potential repertoire of physiological and phenotypical traits related to adaptation and speciation.
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Affiliation(s)
- Alba Blesa
- Department of Biotechnology, Faculty of Experimental Sciences, Universidad Francisco de Vitoria, 28223 Madrid, Spain
- Correspondence: (A.B.); (J.B.); Tel.: +34-91194498 (J.B.)
| | - Ignacio Baquedano
- Centro de Biología Molecular Severo Ochoa (CBMSO), Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain; (I.B.); (S.G.-d.l.F.); (M.M.)
| | - Sandra González-de la Fuente
- Centro de Biología Molecular Severo Ochoa (CBMSO), Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain; (I.B.); (S.G.-d.l.F.); (M.M.)
| | - Mario Mencía
- Centro de Biología Molecular Severo Ochoa (CBMSO), Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain; (I.B.); (S.G.-d.l.F.); (M.M.)
| | - José Berenguer
- Centro de Biología Molecular Severo Ochoa (CBMSO), Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas, 28049 Madrid, Spain; (I.B.); (S.G.-d.l.F.); (M.M.)
- Correspondence: (A.B.); (J.B.); Tel.: +34-91194498 (J.B.)
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31
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Chernova OA, Chernov VM, Mouzykantov AA, Baranova NB, Edelstein IA, Aminov RI. Antimicrobial drug resistance mechanisms among Mollicutes. Int J Antimicrob Agents 2020; 57:106253. [PMID: 33264670 DOI: 10.1016/j.ijantimicag.2020.106253] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 07/08/2020] [Accepted: 11/22/2020] [Indexed: 12/11/2022]
Abstract
Representatives of the Mollicutes class are the smallest, wall-less bacteria capable of independent reproduction. They are widespread in nature, most are commensals, and some are pathogens of humans, animals and plants. They are also the main contaminants of cell cultures and vaccine preparations. Despite limited biosynthetic capabilities, they are highly adaptable and capable of surviving under various stress and extreme conditions, including antimicrobial selective pressure. This review describes current understanding of antibiotic resistance (ABR) mechanisms in Mollicutes. Protective mechanisms in these bacteria include point mutations, which may include non-target genes, and unique gene exchange mechanisms, contributing to transfer of ABR genes. Better understanding of the mechanisms of emergence and dissemination of ABR in Mollicutes is crucial to control these hypermutable bacteria and prevent the occurrence of highly ABR strains.
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Affiliation(s)
- Olga A Chernova
- Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Centre of RAS, Kazan, Russian Federation
| | - Vladislav M Chernov
- Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Centre of RAS, Kazan, Russian Federation
| | - Alexey A Mouzykantov
- Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Centre of RAS, Kazan, Russian Federation
| | - Natalya B Baranova
- Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Centre of RAS, Kazan, Russian Federation
| | - Inna A Edelstein
- Smolensk State Medical University, Ministry of Health of Russian Federation, Smolensk, Russian Federation
| | - Rustam I Aminov
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK; Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russian Federation.
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Bose S, Aggarwal S, Singh DV, Acharya N. Extracellular vesicles: An emerging platform in gram-positive bacteria. MICROBIAL CELL (GRAZ, AUSTRIA) 2020; 7:312-322. [PMID: 33335921 PMCID: PMC7713254 DOI: 10.15698/mic2020.12.737] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 09/07/2020] [Accepted: 09/23/2020] [Indexed: 12/11/2022]
Abstract
Extracellular vesicles (EV), also known as membrane vesicles, are produced as an end product of secretion by both pathogenic and non-pathogenic bacteria. Several reports suggest that archaea, gram-negative bacteria, and eukaryotic cells secrete membrane vesicles as a means for cell-free intercellular communication. EVs influence intercellular communication by transferring a myriad of biomolecules including genetic information. Also, EVs have been implicated in many phenomena such as stress response, intercellular competition, lateral gene transfer, and pathogenicity. However, the cellular process of secreting EVs in gram-positive bacteria is less studied. A notion with the thick cell-walled microbes such as gram-positive bacteria is that the EV release is impossible among them. The role of gram-positive EVs in health and diseases is being studied gradually. Being nano-sized, the EVs from gram-positive bacteria carry a diversity of cargo compounds that have a role in bacterial competition, survival, invasion, host immune evasion, and infection. In this review, we summarise the current understanding of the EVs produced by gram-positive bacteria. Also, we discuss the functional aspects of these components while comparing them with gram-negative bacteria.
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Affiliation(s)
- Swagata Bose
- Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar-751023, India
| | - Shifu Aggarwal
- Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar-751023, India
| | - Durg Vijai Singh
- Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar-751023, India
- Department of Biotechnology, School of Earth, Biological and Environmental Sciences, Central University of South Bihar, Gaya-824236, India
| | - Narottam Acharya
- Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar-751023, India
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Bunduc CM, Bitter W, Houben E. Structure and Function of the Mycobacterial Type VII Secretion Systems. Annu Rev Microbiol 2020; 74:315-335. [DOI: 10.1146/annurev-micro-012420-081657] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Bacteria have evolved intricate secretion machineries for the successful delivery of large molecules across their cell envelopes. Such specialized secretion systems allow a variety of bacteria to thrive in specific host environments. In mycobacteria, type VII secretion systems (T7SSs) are dedicated protein transport machineries that fulfill diverse and crucial roles, ranging from metabolite uptake to immune evasion and subversion to conjugation. Since the discovery of mycobacterial T7SSs about 15 y ago, genetic, structural, and functional studies have provided insight into the roles and functioning of these secretion machineries. Here, we focus on recent advances in the elucidation of the structure and mechanism of mycobacterial T7SSs in protein secretion. As many of these systems are essential for mycobacterial growth or virulence, they provide opportunities for the development of novel therapies to combat a number of relevant mycobacterial diseases.
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Affiliation(s)
- Catalin M. Bunduc
- Section of Molecular Microbiology, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, 1081 HZ Amsterdam, The Netherlands
| | - W. Bitter
- Section of Molecular Microbiology, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, 1081 HZ Amsterdam, The Netherlands
- Department of Medical Microbiology and Infection Control, Amsterdam Infection and Immunity Institute, Amsterdam University Medical Centers, 1007 MB Amsterdam, The Netherlands
| | - E.N.G. Houben
- Section of Molecular Microbiology, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, 1081 HZ Amsterdam, The Netherlands
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Saak CC, Dinh CB, Dutton RJ. Experimental approaches to tracking mobile genetic elements in microbial communities. FEMS Microbiol Rev 2020; 44:606-630. [PMID: 32672812 PMCID: PMC7476777 DOI: 10.1093/femsre/fuaa025] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 06/29/2020] [Indexed: 12/19/2022] Open
Abstract
Horizontal gene transfer is an important mechanism of microbial evolution and is often driven by the movement of mobile genetic elements between cells. Due to the fact that microbes live within communities, various mechanisms of horizontal gene transfer and types of mobile elements can co-occur. However, the ways in which horizontal gene transfer impacts and is impacted by communities containing diverse mobile elements has been challenging to address. Thus, the field would benefit from incorporating community-level information and novel approaches alongside existing methods. Emerging technologies for tracking mobile elements and assigning them to host organisms provide promise for understanding the web of potential DNA transfers in diverse microbial communities more comprehensively. Compared to existing experimental approaches, chromosome conformation capture and methylome analyses have the potential to simultaneously study various types of mobile elements and their associated hosts. We also briefly discuss how fermented food microbiomes, given their experimental tractability and moderate species complexity, make ideal models to which to apply the techniques discussed herein and how they can be used to address outstanding questions in the field of horizontal gene transfer in microbial communities.
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Affiliation(s)
- Christina C Saak
- Division of Biological Sciences, Section of Molecular Biology, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Cong B Dinh
- Division of Biological Sciences, Section of Molecular Biology, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Rachel J Dutton
- Division of Biological Sciences, Section of Molecular Biology, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
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Fodor A, Abate BA, Deák P, Fodor L, Gyenge E, Klein MG, Koncz Z, Muvevi J, Ötvös L, Székely G, Vozik D, Makrai L. Multidrug Resistance (MDR) and Collateral Sensitivity in Bacteria, with Special Attention to Genetic and Evolutionary Aspects and to the Perspectives of Antimicrobial Peptides-A Review. Pathogens 2020; 9:pathogens9070522. [PMID: 32610480 PMCID: PMC7399985 DOI: 10.3390/pathogens9070522] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 06/23/2020] [Accepted: 06/23/2020] [Indexed: 12/18/2022] Open
Abstract
Antibiotic poly-resistance (multidrug-, extreme-, and pan-drug resistance) is controlled by adaptive evolution. Darwinian and Lamarckian interpretations of resistance evolution are discussed. Arguments for, and against, pessimistic forecasts on a fatal “post-antibiotic era” are evaluated. In commensal niches, the appearance of a new antibiotic resistance often reduces fitness, but compensatory mutations may counteract this tendency. The appearance of new antibiotic resistance is frequently accompanied by a collateral sensitivity to other resistances. Organisms with an expanding open pan-genome, such as Acinetobacter baumannii, Pseudomonas aeruginosa, and Klebsiella pneumoniae, can withstand an increased number of resistances by exploiting their evolutionary plasticity and disseminating clonally or poly-clonally. Multidrug-resistant pathogen clones can become predominant under antibiotic stress conditions but, under the influence of negative frequency-dependent selection, are prevented from rising to dominance in a population in a commensal niche. Antimicrobial peptides have a great potential to combat multidrug resistance, since antibiotic-resistant bacteria have shown a high frequency of collateral sensitivity to antimicrobial peptides. In addition, the mobility patterns of antibiotic resistance, and antimicrobial peptide resistance, genes are completely different. The integron trade in commensal niches is fortunately limited by the species-specificity of resistance genes. Hence, we theorize that the suggested post-antibiotic era has not yet come, and indeed might never come.
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Affiliation(s)
- András Fodor
- Department of Genetics, University of Szeged, H-6726 Szeged, Hungary;
- Correspondence: or (A.F.); (L.M.); Tel.: +36-(30)-490-9294 (A.F.); +36-(30)-271-2513 (L.M.)
| | - Birhan Addisie Abate
- Ethiopian Biotechnology Institute, Agricultural Biotechnology Directorate, Addis Ababa 5954, Ethiopia;
| | - Péter Deák
- Department of Genetics, University of Szeged, H-6726 Szeged, Hungary;
- Institute of Biochemistry, Biological Research Centre, H-6726 Szeged, Hungary
| | - László Fodor
- Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, P.O. Box 22, H-1581 Budapest, Hungary;
| | - Ervin Gyenge
- Hungarian Department of Biology and Ecology, Faculty of Biology and Geology, Babeș-Bolyai University, 5-7 Clinicilor St., 400006 Cluj-Napoca, Romania; (E.G.); (G.S.)
- Institute for Research-Development-Innovation in Applied Natural Sciences, Babeș-Bolyai University, 30 Fântânele St., 400294 Cluj-Napoca, Romania
| | - Michael G. Klein
- Department of Entomology, The Ohio State University, 1680 Madison Ave., Wooster, OH 44691, USA;
| | - Zsuzsanna Koncz
- Max-Planck Institut für Pflanzenzüchtungsforschung, Carl-von-Linné-Weg 10, D-50829 Köln, Germany;
| | | | - László Ötvös
- OLPE, LLC, Audubon, PA 19403-1965, USA;
- Institute of Medical Microbiology, Semmelweis University, H-1085 Budapest, Hungary
- Arrevus, Inc., Raleigh, NC 27612, USA
| | - Gyöngyi Székely
- Hungarian Department of Biology and Ecology, Faculty of Biology and Geology, Babeș-Bolyai University, 5-7 Clinicilor St., 400006 Cluj-Napoca, Romania; (E.G.); (G.S.)
- Institute for Research-Development-Innovation in Applied Natural Sciences, Babeș-Bolyai University, 30 Fântânele St., 400294 Cluj-Napoca, Romania
- Centre for Systems Biology, Biodiversity and Bioresources, Babeș-Bolyai University, 5-7 Clinicilor St., 400006 Cluj-Napoca, Romania
| | - Dávid Vozik
- Research Institute on Bioengineering, Membrane Technology and Energetics, Faculty of Engineering, University of Veszprem, H-8200 Veszprém, Hungary; or or
| | - László Makrai
- Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, P.O. Box 22, H-1581 Budapest, Hungary;
- Correspondence: or (A.F.); (L.M.); Tel.: +36-(30)-490-9294 (A.F.); +36-(30)-271-2513 (L.M.)
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Chromosomal Recombination Targets in Chlamydia Interspecies Lateral Gene Transfer. J Bacteriol 2019; 201:JB.00365-19. [PMID: 31501285 DOI: 10.1128/jb.00365-19] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 09/03/2019] [Indexed: 12/12/2022] Open
Abstract
Lateral gene transfer (LGT) among Chlamydia trachomatis strains is common, in both isolates generated in the laboratory and those examined directly from patients. In contrast, there are very few examples of recent acquisition of DNA by any Chlamydia spp. from any other species. Interspecies LGT in this system was analyzed using crosses of tetracycline (Tc)-resistant C. trachomatis L2/434 and chloramphenicol (Cam)-resistant C. muridarum VR-123. Parental C. muridarum strains were created using a plasmid-based Himar transposition system, which led to integration of the Camr marker randomly across the chromosome. Fragments encompassing 79% of the C. muridarum chromosome were introduced into a C. trachomatis background, with the total coverage contained on 142 independent recombinant clones. Genome sequence analysis of progeny strains identified candidate recombination hot spots, a property not consistent with in vitro C. trachomatis × C. trachomatis (intraspecies) crosses. In both interspecies and intraspecies crosses, there were examples of duplications, mosaic recombination endpoints, and recombined sequences that were not linked to the selection marker. Quantitative analysis of the distribution and constitution of inserted sequences indicated that there are different constraints on interspecies LGT than on intraspecies crosses. These constraints may help explain why there is so little evidence of interspecies genetic exchange in this system, which is in contrast to very widespread intraspecies exchange in C. trachomatis IMPORTANCE Genome sequence analysis has demonstrated that there is widespread lateral gene transfer among strains within the species C. trachomatis and with other closely related Chlamydia species in laboratory experiments. This is in contrast to the complete absence of foreign DNA in the genomes of sequenced clinical C. trachomatis strains. There is no understanding of any mechanisms of genetic transfer in this important group of pathogens. In this report, we demonstrate that interspecies genetic exchange can occur but that the nature of the fragments exchanged is different than those observed in intraspecies crosses. We also generated a large hybrid strain library that can be exploited to examine important aspects of chlamydial disease.
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Dordet-Frisoni E, Faucher M, Sagné E, Baranowski E, Tardy F, Nouvel LX, Citti C. Mycoplasma Chromosomal Transfer: A Distributive, Conjugative Process Creating an Infinite Variety of Mosaic Genomes. Front Microbiol 2019; 10:2441. [PMID: 31708906 PMCID: PMC6819513 DOI: 10.3389/fmicb.2019.02441] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 10/10/2019] [Indexed: 11/13/2022] Open
Abstract
The capacity of Mycoplasmas to engage in horizontal gene transfers has recently been highlighted. Despite their small genome, some of these wall-less bacteria are able to exchange multiple, large portions of their chromosome via a conjugative mechanism that does not conform to canonical Hfr/oriT models. To understand the exact features underlying mycoplasma chromosomal transfer (MCT), extensive genomic analyses were performed at the nucleotide level, using individual mating progenies derived from our model organism, Mycoplasma agalactiae. Genome reconstruction showed that MCT resulted in the distributive transfer of multiple chromosomal DNA fragments and generated progenies composed of a variety of mosaic genomes, each being unique. Analyses of macro- and micro-events resulting from MCT revealed that the vast majority of the acquired fragments were unrelated and co-transferred independently from the selection marker, these resulted in up to 17% of the genome being exchanged. Housekeeping and accessory genes were equally affected by MCT, with up to 35 CDSs being gained or lost. This efficient HGT process also created a number of chimeric genes and genetic micro-variations that may impact gene regulation and/or expression. Our study unraveled the tremendous plasticity of M. agalactiae genome and point toward MCT as a major player in diversification and adaptation to changing environments, offering a significant advantage to this minimal pathogen.
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Affiliation(s)
| | - Marion Faucher
- IHAP, INRA, ENVT, Université de Toulouse, Toulouse, France
| | - Eveline Sagné
- IHAP, INRA, ENVT, Université de Toulouse, Toulouse, France
| | | | - Florence Tardy
- UMR Mycoplasmoses des Ruminants, VetAgro Sup, Laboratoire de Lyon, ANSES, Université de Lyon, Marcy-l'Étoile, France
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38
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Chiner-Oms Á, Comas I. Large genomics datasets shed light on the evolution of the Mycobacterium tuberculosis complex. INFECTION GENETICS AND EVOLUTION 2019; 72:10-15. [DOI: 10.1016/j.meegid.2019.02.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 02/21/2019] [Accepted: 02/25/2019] [Indexed: 01/21/2023]
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Guzmán-Herrador DL, Llosa M. The secret life of conjugative relaxases. Plasmid 2019; 104:102415. [PMID: 31103521 DOI: 10.1016/j.plasmid.2019.102415] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 04/17/2019] [Accepted: 05/02/2019] [Indexed: 10/26/2022]
Abstract
Conjugative relaxases are well-characterized proteins responsible for the site- and strand-specific endonucleolytic cleavage and strand transfer reactions taking place at the start and end of the conjugative DNA transfer process. Most of the relaxases characterized biochemically and structurally belong to the HUH family of endonucleases. However, an increasing number of new families of relaxases are revealing a variety of protein folds and catalytic alternatives to accomplish conjugative DNA processing. Relaxases show high specificity for their cognate target DNA sequences, but several recent reports underscore the importance of their activity on secondary targets, leading to widespread mobilization of plasmids containing an oriT-like sequence. Some relaxases perform other functions associated with their nicking and strand transfer ability, such as catalyzing site-specific recombination or initiation of plasmid replication. They perform these roles in the absence of conjugation, and the validation of these functions in several systems strongly suggest that they are not mere artifactual laboratory observations. Other unexpected roles recently assigned to relaxases include controlling plasmid copy number and promoting retrotransposition. Their capacity to mediate promiscuous mobilization and genetic reorganizations can be exploited for a number of imaginative biotechnological applications. Overall, there is increasing evidence that conjugative relaxases are not only key enzymes for horizontal gene transfer, but may have been adapted to perform other roles which contribute to prokaryotic genetic plasticity. Relaxed target specificity may be key to this versatility.
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Affiliation(s)
- Dolores Lucía Guzmán-Herrador
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Universidad de Cantabria-CSIC-SODERCAN, Santander, Spain
| | - Matxalen Llosa
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), Universidad de Cantabria-CSIC-SODERCAN, Santander, Spain.
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40
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Behra PRK, Das S, Pettersson BMF, Shirreff L, DuCote T, Jacobsson KG, Ennis DG, Kirsebom LA. Extended insight into the Mycobacterium chelonae-abscessus complex through whole genome sequencing of Mycobacterium salmoniphilum outbreak and Mycobacterium salmoniphilum-like strains. Sci Rep 2019; 9:4603. [PMID: 30872669 PMCID: PMC6418233 DOI: 10.1038/s41598-019-40922-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 02/26/2019] [Indexed: 12/12/2022] Open
Abstract
Members of the Mycobacterium chelonae-abscessus complex (MCAC) are close to the mycobacterial ancestor and includes both human, animal and fish pathogens. We present the genomes of 14 members of this complex: the complete genomes of Mycobacterium salmoniphilum and Mycobacterium chelonae type strains, seven M. salmoniphilum isolates, and five M. salmoniphilum-like strains including strains isolated during an outbreak in an animal facility at Uppsala University. Average nucleotide identity (ANI) analysis and core gene phylogeny revealed that the M. salmoniphilum-like strains are variants of the human pathogen Mycobacterium franklinii and phylogenetically close to Mycobacterium abscessus. Our data further suggested that M. salmoniphilum separates into three branches named group I, II and III with the M. salmoniphilum type strain belonging to group II. Among predicted virulence factors, the presence of phospholipase C (plcC), which is a major virulence factor that makes M. abscessus highly cytotoxic to mouse macrophages, and that M. franklinii originally was isolated from infected humans make it plausible that the outbreak in the animal facility was caused by a M. salmoniphilum-like strain. Interestingly, M. salmoniphilum-like was isolated from tap water suggesting that it can be present in the environment. Moreover, we predicted the presence of mutational hotspots in the M. salmoniphilum isolates and 26% of these hotspots overlap with genes categorized as having roles in virulence, disease and defense. We also provide data about key genes involved in transcription and translation such as sigma factor, ribosomal protein and tRNA genes.
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Affiliation(s)
- Phani Rama Krishna Behra
- Department of Cell and Molecular Biology, Box 596, Biomedical Centre, SE-751 24, Uppsala, Sweden
| | - Sarbashis Das
- Department of Cell and Molecular Biology, Box 596, Biomedical Centre, SE-751 24, Uppsala, Sweden
| | - B M Fredrik Pettersson
- Department of Cell and Molecular Biology, Box 596, Biomedical Centre, SE-751 24, Uppsala, Sweden
| | - Lisa Shirreff
- Department of Biology, University of Louisiana, Lafayette, Louisiana, USA
| | - Tanner DuCote
- Department of Biology, University of Louisiana, Lafayette, Louisiana, USA
| | | | - Don G Ennis
- Department of Biology, University of Louisiana, Lafayette, Louisiana, USA
| | - Leif A Kirsebom
- Department of Cell and Molecular Biology, Box 596, Biomedical Centre, SE-751 24, Uppsala, Sweden.
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Davidson RM. A Closer Look at the Genomic Variation of Geographically Diverse Mycobacterium abscessus Clones That Cause Human Infection and Disease. Front Microbiol 2018; 9:2988. [PMID: 30568642 PMCID: PMC6290055 DOI: 10.3389/fmicb.2018.02988] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 11/19/2018] [Indexed: 01/15/2023] Open
Abstract
Mycobacterium abscessus is a multidrug resistant bacterium that causes pulmonary and extrapulmonary disease. The reported prevalence of pulmonary M. abscessus infections appears to be increasing in the United States (US) and around the world. In the last five years, multiple studies have utilized whole genome sequencing to investigate the genetic epidemiology of two clinically relevant subspecies, M. abscessus subsp. abscessus (MAB) and M. abscessus subsp. massiliense (MMAS). Phylogenomic comparisons of clinical isolates revealed that substantial proportions of patients have MAB and MMAS isolates that belong to genetically similar clusters also known as ‘dominant clones’. Unlike the genetic lineages of Mycobacterium tuberculosis that tend to be geographically clustered, the MAB and MMAS clones have been found in clinical populations from the US, Europe, Australia and South America. Moreover, the clones have been associated with worse clinical outcomes and show increased pathogenicity in macrophage and mouse models. While some have suggested that they may have spread locally and then globally through ‘indirect transmission’ within cystic fibrosis (CF) clinics, isolates of these clones have also been associated with sporadic pulmonary infections in non-CF patients and unrelated hospital-acquired soft tissue infections. M. abscessus has long been thought to be acquired from the environment, but the prevalence, exposure risk and environmental reservoirs of the dominant clones are currently not known. This review summarizes the genomic studies of M. abscessus and synthesizes the current knowledge surrounding the geographically diverse dominant clones identified from patient samples. Furthermore, it discusses the limitations of core genome comparisons for studying these genetically similar isolates and explores the breadth of accessory genome variation that has been observed to date. The combination of both core and accessory genome variation among these isolates may be the key to elucidating the origin, spread and evolution of these frequent genotypes.
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Affiliation(s)
- Rebecca M Davidson
- Center for Genes, Environment and Health, National Jewish Health, Denver, CO, United States
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42
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Clark RR, Judd J, Lasek-Nesselquist E, Montgomery SA, Hoffmann JG, Derbyshire KM, Gray TA. Direct cell-cell contact activates SigM to express the ESX-4 secretion system in Mycobacterium smegmatis. Proc Natl Acad Sci U S A 2018; 115:E6595-E6603. [PMID: 29941598 PMCID: PMC6048512 DOI: 10.1073/pnas.1804227115] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Conjugal cell-cell contact between strains of Mycobacterium smegmatis induces the esxUT transcript, which encodes the putative primary substrates of the ESAT-6 secretion system 4 (ESX-4) secretion system. This recipient response was required for conjugal transfer of chromosomal DNA from the donor strain. Here we show that the extracytoplasmic σ factor, SigM, is a cell contact-dependent activator of ESX-4 expression and is required for conjugal transfer of DNA in the recipient strain. The SigM regulon includes genes outside the seven-gene core esx4 locus that we show are also required for conjugation, and we show that some of these SigM-induced proteins likely function through ESX-4. A fluorescent reporter revealed that SigM is specifically activated in recipient cells in direct contact with donor cells. Coculture RNA-seq experiments indicated that SigM regulon induction occurred early and before transconjugants are detected. This work supports a model wherein donor contact with the recipient cell surface inactivates the transmembrane anti-SigM, thereby releasing SigM. Free SigM induces an extended ESX-4 secretion system, resulting in changes that facilitate chromosomal transfer. The contact-dependent inactivation of an extracytoplasmic σ-factor that tightly controls ESX-4 activity suggests a mechanism dedicated to detect, and appropriately respond to, external stimuli from mycobacteria.
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Affiliation(s)
- Ryan R Clark
- Division of Genetics, Wadsworth Center, New York State Department of Health, Albany, NY 12208
| | - Julius Judd
- Division of Genetics, Wadsworth Center, New York State Department of Health, Albany, NY 12208
| | - Erica Lasek-Nesselquist
- Division of Genetics, Wadsworth Center, New York State Department of Health, Albany, NY 12208
| | - Sarah A Montgomery
- Division of Genetics, Wadsworth Center, New York State Department of Health, Albany, NY 12208
- Department of Biomedical Sciences, University at Albany, Albany, NY 12208
| | - Jennifer G Hoffmann
- Division of Genetics, Wadsworth Center, New York State Department of Health, Albany, NY 12208
| | - Keith M Derbyshire
- Division of Genetics, Wadsworth Center, New York State Department of Health, Albany, NY 12208;
- Department of Biomedical Sciences, University at Albany, Albany, NY 12208
| | - Todd A Gray
- Division of Genetics, Wadsworth Center, New York State Department of Health, Albany, NY 12208;
- Department of Biomedical Sciences, University at Albany, Albany, NY 12208
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