1
|
Beamud B, Benz F, Bikard D. Going viral: The role of mobile genetic elements in bacterial immunity. Cell Host Microbe 2024; 32:804-819. [PMID: 38870898 DOI: 10.1016/j.chom.2024.05.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 05/17/2024] [Accepted: 05/20/2024] [Indexed: 06/15/2024]
Abstract
Bacteriophages and other mobile genetic elements (MGEs) pose a significant threat to bacteria, subjecting them to constant attacks. In response, bacteria have evolved a sophisticated immune system that employs diverse defensive strategies and mechanisms. Remarkably, a growing body of evidence suggests that most of these defenses are encoded by MGEs themselves. This realization challenges our traditional understanding of bacterial immunity and raises intriguing questions about the evolutionary forces at play. Our review provides a comprehensive overview of the latest findings on the main families of MGEs and the defense systems they encode. We also highlight how a vast diversity of defense systems remains to be discovered and their mechanism of mobility understood. Altogether, the composition and distribution of defense systems in bacterial genomes only makes sense in the light of the ecological and evolutionary interactions of a complex network of MGEs.
Collapse
Affiliation(s)
- Beatriz Beamud
- Institut Pasteur, Université de Paris, Synthetic Biology, 75015 Paris, France.
| | - Fabienne Benz
- Institut Pasteur, Université de Paris, Synthetic Biology, 75015 Paris, France; Institut Pasteur, Université Paris Cité, CNRS UMR3525, Microbial Evolutionary Genomics, 75015 Paris, France
| | - David Bikard
- Institut Pasteur, Université de Paris, Synthetic Biology, 75015 Paris, France.
| |
Collapse
|
2
|
Hossain AA, Pigli YZ, Baca CF, Heissel S, Thomas A, Libis VK, Burian J, Chappie JS, Brady SF, Rice PA, Marraffini LA. DNA glycosylases provide antiviral defence in prokaryotes. Nature 2024; 629:410-416. [PMID: 38632404 PMCID: PMC11078745 DOI: 10.1038/s41586-024-07329-9] [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: 05/19/2023] [Accepted: 03/15/2024] [Indexed: 04/19/2024]
Abstract
Bacteria have adapted to phage predation by evolving a vast assortment of defence systems1. Although anti-phage immunity genes can be identified using bioinformatic tools, the discovery of novel systems is restricted to the available prokaryotic sequence data2. Here, to overcome this limitation, we infected Escherichia coli carrying a soil metagenomic DNA library3 with the lytic coliphage T4 to isolate clones carrying protective genes. Following this approach, we identified Brig1, a DNA glycosylase that excises α-glucosyl-hydroxymethylcytosine nucleobases from the bacteriophage T4 genome to generate abasic sites and inhibit viral replication. Brig1 homologues that provide immunity against T-even phages are present in multiple phage defence loci across distinct clades of bacteria. Our study highlights the benefits of screening unsequenced DNA and reveals prokaryotic DNA glycosylases as important players in the bacteria-phage arms race.
Collapse
Affiliation(s)
- Amer A Hossain
- Laboratory of Bacteriology, The Rockefeller University, New York, NY, USA
| | - Ying Z Pigli
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
| | - Christian F Baca
- Laboratory of Bacteriology, The Rockefeller University, New York, NY, USA
| | - Søren Heissel
- Proteomics Resource Center, The Rockefeller University, New York, NY, USA
| | - Alexis Thomas
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
| | - Vincent K Libis
- Laboratory of Genetically Encoded Small Molecules, The Rockefeller University, New York, NY, USA
| | - Ján Burian
- Laboratory of Genetically Encoded Small Molecules, The Rockefeller University, New York, NY, USA
| | - Joshua S Chappie
- Department of Molecular Medicine, Cornell University, Ithaca, NY, USA
| | - Sean F Brady
- Laboratory of Genetically Encoded Small Molecules, The Rockefeller University, New York, NY, USA
| | - Phoebe A Rice
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA.
| | - Luciano A Marraffini
- Laboratory of Bacteriology, The Rockefeller University, New York, NY, USA.
- Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA.
| |
Collapse
|
3
|
Rostøl JT, Quiles-Puchalt N, Iturbe-Sanz P, Lasa Í, Penadés JR. Bacteriophages avoid autoimmunity from cognate immune systems as an intrinsic part of their life cycles. Nat Microbiol 2024; 9:1312-1324. [PMID: 38565896 PMCID: PMC11087260 DOI: 10.1038/s41564-024-01661-6] [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: 04/06/2023] [Accepted: 03/04/2024] [Indexed: 04/04/2024]
Abstract
Dormant prophages protect lysogenic cells by expressing diverse immune systems, which must avoid targeting their cognate prophages upon activation. Here we report that multiple Staphylococcus aureus prophages encode Tha (tail-activated, HEPN (higher eukaryotes and prokaryotes nucleotide-binding) domain-containing anti-phage system), a defence system activated by structural tail proteins of incoming phages. We demonstrate the function of two Tha systems, Tha-1 and Tha-2, activated by distinct tail proteins. Interestingly, Tha systems can also block reproduction of the induced tha-positive prophages. To prevent autoimmunity after prophage induction, these systems are inhibited by the product of a small overlapping antisense gene previously believed to encode an excisionase. This genetic organization, conserved in S. aureus prophages, allows Tha systems to protect prophages and their bacterial hosts against phage predation and to be turned off during prophage induction, balancing immunity and autoimmunity. Our results show that the fine regulation of these processes is essential for the correct development of prophages' life cycle.
Collapse
Affiliation(s)
- Jakob T Rostøl
- Centre for Bacterial Resistance Biology, Imperial College London, London, UK.
| | - Nuria Quiles-Puchalt
- Centre for Bacterial Resistance Biology, Imperial College London, London, UK
- School of Health Sciences, Universidad CEU Cardenal Herrera, CEU Universities, Alfara del Patriarca, Spain
| | - Pablo Iturbe-Sanz
- Laboratory of Microbial Pathogenesis. Navarrabiomed, Hospital Universitario de Navarra (HUN), Universidad Pública de Navarra (UPNA), IdiSNA, Pamplona, Spain
| | - Íñigo Lasa
- Laboratory of Microbial Pathogenesis. Navarrabiomed, Hospital Universitario de Navarra (HUN), Universidad Pública de Navarra (UPNA), IdiSNA, Pamplona, Spain
| | - José R Penadés
- Centre for Bacterial Resistance Biology, Imperial College London, London, UK.
| |
Collapse
|
4
|
Martínez M, Rizzuto I, Molina R. Knowing Our Enemy in the Antimicrobial Resistance Era: Dissecting the Molecular Basis of Bacterial Defense Systems. Int J Mol Sci 2024; 25:4929. [PMID: 38732145 PMCID: PMC11084316 DOI: 10.3390/ijms25094929] [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: 03/20/2024] [Revised: 04/26/2024] [Accepted: 04/29/2024] [Indexed: 05/13/2024] Open
Abstract
Bacteria and their phage adversaries are engaged in an ongoing arms race, resulting in the development of a broad antiphage arsenal and corresponding viral countermeasures. In recent years, the identification and utilization of CRISPR-Cas systems have driven a renewed interest in discovering and characterizing antiphage mechanisms, revealing a richer diversity than initially anticipated. Currently, these defense systems can be categorized based on the bacteria's strategy associated with the infection cycle stage. Thus, bacterial defense systems can degrade the invading genetic material, trigger an abortive infection, or inhibit genome replication. Understanding the molecular mechanisms of processes related to bacterial immunity has significant implications for phage-based therapies and the development of new biotechnological tools. This review aims to comprehensively cover these processes, with a focus on the most recent discoveries.
Collapse
Affiliation(s)
| | | | - Rafael Molina
- Department of Crystallography and Structural Biology, Instituto de Química-Física Blas Cabrera, Consejo Superior de Investigaciones Científicas, 28006 Madrid, Spain
| |
Collapse
|
5
|
Agapov A, Baker KS, Bedekar P, Bhatia RP, Blower TR, Brockhurst MA, Brown C, Chong CE, Fothergill JL, Graham S, Hall JP, Maestri A, McQuarrie S, Olina A, Pagliara S, Recker M, Richmond A, Shaw SJ, Szczelkun MD, Taylor TB, van Houte S, Went SC, Westra ER, White MF, Wright R. Multi-layered genome defences in bacteria. Curr Opin Microbiol 2024; 78:102436. [PMID: 38368839 DOI: 10.1016/j.mib.2024.102436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 01/22/2024] [Accepted: 01/23/2024] [Indexed: 02/20/2024]
Abstract
Bacteria have evolved a variety of defence mechanisms to protect against mobile genetic elements, including restriction-modification systems and CRISPR-Cas. In recent years, dozens of previously unknown defence systems (DSs) have been discovered. Notably, diverse DSs often coexist within the same genome, and some co-occur at frequencies significantly higher than would be expected by chance, implying potential synergistic interactions. Recent studies have provided evidence of defence mechanisms that enhance or complement one another. Here, we review the interactions between DSs at the mechanistic, regulatory, ecological and evolutionary levels.
Collapse
Affiliation(s)
- Aleksei Agapov
- ESI, Centre for Ecology and Conservation, University of Exeter, UK
| | - Kate S Baker
- Department of Genetics, University of Cambridge, CB2 3EH, UK
| | - Paritosh Bedekar
- ESI, Centre for Ecology and Conservation, University of Exeter, UK
| | - Rama P Bhatia
- ESI, Centre for Ecology and Conservation, University of Exeter, UK
| | - Tim R Blower
- Department of Biosciences, Durham University, Stockton Road, Durham DH1 3LE, UK
| | - Michael A Brockhurst
- Division of Evolution, Infection and Genomics, School of Biological Sciences, University of Manchester, Dover Street, Manchester M13 9PT, UK
| | - Cooper Brown
- School of Biology, University of St Andrews, St Andrews KY16 9ST, UK
| | | | - Joanne L Fothergill
- Dept of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, UK
| | - Shirley Graham
- School of Biology, University of St Andrews, St Andrews KY16 9ST, UK
| | - James Pj Hall
- Dept of Evolution, Ecology and Behaviour, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, L69 7ZB, UK
| | - Alice Maestri
- ESI, Centre for Ecology and Conservation, University of Exeter, UK
| | - Stuart McQuarrie
- School of Biology, University of St Andrews, St Andrews KY16 9ST, UK
| | - Anna Olina
- ESI, Centre for Ecology and Conservation, University of Exeter, UK
| | | | - Mario Recker
- ESI, Centre for Ecology and Conservation, University of Exeter, UK
| | - Anna Richmond
- ESI, Centre for Ecology and Conservation, University of Exeter, UK
| | - Steven J Shaw
- DNA-Protein Interactions Unit, School of Biochemistry, University of Bristol, Bristol BS6 7YB, UK
| | - Mark D Szczelkun
- DNA-Protein Interactions Unit, School of Biochemistry, University of Bristol, Bristol BS6 7YB, UK
| | - Tiffany B Taylor
- Milner Centre for Evolution, Department of Life Sciences, University of Bath, Claverton Down, Bath BA2 7AY, UK
| | | | - Sam C Went
- Department of Biosciences, Durham University, Stockton Road, Durham DH1 3LE, UK
| | - Edze R Westra
- ESI, Centre for Ecology and Conservation, University of Exeter, UK.
| | - Malcolm F White
- School of Biology, University of St Andrews, St Andrews KY16 9ST, UK
| | - Rosanna Wright
- Division of Evolution, Infection and Genomics, School of Biological Sciences, University of Manchester, Dover Street, Manchester M13 9PT, UK
| |
Collapse
|
6
|
Patel PH, Taylor VL, Zhang C, Getz LJ, Fitzpatrick AD, Davidson AR, Maxwell KL. Anti-phage defence through inhibition of virion assembly. Nat Commun 2024; 15:1644. [PMID: 38388474 PMCID: PMC10884400 DOI: 10.1038/s41467-024-45892-x] [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: 11/21/2023] [Accepted: 02/06/2024] [Indexed: 02/24/2024] Open
Abstract
Bacteria have evolved diverse antiviral defence mechanisms to protect themselves against phage infection. Phages integrated into bacterial chromosomes, known as prophages, also encode defences that protect the bacterial hosts in which they reside. Here, we identify a type of anti-phage defence that interferes with the virion assembly pathway of invading phages. The protein that mediates this defence, which we call Tab (for 'Tail assembly blocker'), is constitutively expressed from a Pseudomonas aeruginosa prophage. Tab allows the invading phage replication cycle to proceed, but blocks assembly of the phage tail, thus preventing formation of infectious virions. While the infected cell dies through the activity of the replicating phage lysis proteins, there is no release of infectious phage progeny, and the bacterial community is thereby protected from a phage epidemic. Prophages expressing Tab are not inhibited during their own lytic cycle because they express a counter-defence protein that interferes with Tab function. Thus, our work reveals an anti-phage defence that operates by blocking virion assembly, thereby both preventing formation of phage progeny and allowing destruction of the infected cell due to expression of phage lysis genes.
Collapse
Affiliation(s)
| | | | - Chi Zhang
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Landon J Getz
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | | | - Alan R Davidson
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Karen L Maxwell
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada.
| |
Collapse
|
7
|
Jiang YN, Tamiya-Ishitsuka H, Aoi R, Okabe T, Yokota A, Noda N. MazEF Homologs in Symbiobacterium thermophilum Exhibit Cross-Neutralization with Non-Cognate MazEFs. Toxins (Basel) 2024; 16:81. [PMID: 38393159 PMCID: PMC10893535 DOI: 10.3390/toxins16020081] [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: 12/28/2023] [Revised: 01/25/2024] [Accepted: 01/30/2024] [Indexed: 02/25/2024] Open
Abstract
Toxin-antitoxin systems are preserved by nearly every prokaryote. The type II toxin MazF acts as a sequence-specific endoribonuclease, cleaving ribonucleotides at specific sequences that vary from three to seven bases, as has been reported in different host organisms to date. The present study characterized the MazEF module (MazEF-sth) conserved in the Symbiobacterium thermophilum IAM14863 strain, a Gram-negative syntrophic bacterium that can be supported by co-culture with multiple bacteria, including Bacillus subtilis. Based on a method combining massive parallel sequencing and the fluorometric assay, MazF-sth was determined to cleave ribonucleotides at the UACAUA motif, which is markedly similar to the motifs recognized by MazF from B. subtilis (MazF-bs), and by several MazFs from Gram-positive bacteria. MazF-sth, with mutations at conserved amino acid residues Arg29 and Thr52, lost most ribonuclease activity, indicating that these residues that are crucial for MazF-bs also play significant roles in MazF-sth catalysis. Further, cross-neutralization between MazF-sth and the non-cognate MazE-bs was discovered, and herein, the neutralization mechanism is discussed based on a protein-structure simulation via AlphaFold2 and multiple sequence alignment. The conflict between the high homology shared by these MazF amino acid sequences and the few genetic correlations among their host organisms may provide evidence of horizontal gene transfer.
Collapse
Affiliation(s)
- Yu-Nong Jiang
- Master’s/Doctoral Program in Life Science Innovation, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba 305-8572, Ibaraki, Japan
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Ibaraki, Japan
| | - Hiroko Tamiya-Ishitsuka
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Ibaraki, Japan
| | - Rie Aoi
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Ibaraki, Japan
- Department of Life Science and Medical Bioscience, Waseda University, Shinjuku-ku 162-8480, Tokyo, Japan
| | - Takuma Okabe
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Ibaraki, Japan
- Department of Life Science and Medical Bioscience, Waseda University, Shinjuku-ku 162-8480, Tokyo, Japan
| | - Akiko Yokota
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Ibaraki, Japan
| | - Naohiro Noda
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Ibaraki, Japan
- Department of Life Science and Medical Bioscience, Waseda University, Shinjuku-ku 162-8480, Tokyo, Japan
- Master’s/Doctoral Program in Life Science Innovation, School of Integrative and Global Majors, University of Tsukuba, Tsukuba 305-8572, Ibaraki, Japan
| |
Collapse
|
8
|
Barcia-Cruz R, Goudenège D, Moura de Sousa JA, Piel D, Marbouty M, Rocha EPC, Le Roux F. Phage-inducible chromosomal minimalist islands (PICMIs), a novel family of small marine satellites of virulent phages. Nat Commun 2024; 15:664. [PMID: 38253718 PMCID: PMC10803314 DOI: 10.1038/s41467-024-44965-1] [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: 08/10/2023] [Accepted: 01/10/2024] [Indexed: 01/24/2024] Open
Abstract
Phage satellites are bacterial genetic elements that co-opt phage machinery for their own dissemination. Here we identify a family of satellites, named Phage-Inducible Chromosomal Minimalist Islands (PICMIs), that are broadly distributed in marine bacteria of the family Vibrionaceae. A typical PICMI is characterized by reduced gene content, does not encode genes for capsid remodelling, and packages its DNA as a concatemer. PICMIs integrate in the bacterial host genome next to the fis regulator, and encode three core proteins necessary for excision and replication. PICMIs are dependent on virulent phage particles to spread to other bacteria, and protect their hosts from other competitive phages without interfering with their helper phage. Thus, our work broadens our understanding of phage satellites and narrows down the minimal number of functions necessary to hijack a tailed phage.
Collapse
Affiliation(s)
- Rubén Barcia-Cruz
- Sorbonne Université, CNRS, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff cedex, France
- Department of Microbiology and Parasitology, CIBUS-Faculty of Biology, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - David Goudenège
- Sorbonne Université, CNRS, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff cedex, France
- Ifremer, Unité Physiologie Fonctionnelle des Organismes Marins, ZI de la Pointe du Diable, CS 10070, F-29280, Plouzané, France
| | - Jorge A Moura de Sousa
- Institut Pasteur, Université Paris Cité, CNRS UMR3525, Microbial Evolutionary Genomics, Paris, France
| | - Damien Piel
- Sorbonne Université, CNRS, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff cedex, France
- Ifremer, Unité Physiologie Fonctionnelle des Organismes Marins, ZI de la Pointe du Diable, CS 10070, F-29280, Plouzané, France
| | - Martial Marbouty
- Institut Pasteur, Université Paris Cité, Organization and Dynamics of Viral Genomes Group, CNRS UMR 3525, Paris, F-75015, France
| | - Eduardo P C Rocha
- Institut Pasteur, Université Paris Cité, CNRS UMR3525, Microbial Evolutionary Genomics, Paris, France
| | - Frédérique Le Roux
- Sorbonne Université, CNRS, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, F-29688, Roscoff cedex, France.
- Ifremer, Unité Physiologie Fonctionnelle des Organismes Marins, ZI de la Pointe du Diable, CS 10070, F-29280, Plouzané, France.
- Département de microbiologie, infectiologie et immunologie, Université de Montréal, Montréal, Canada.
| |
Collapse
|
9
|
Guler P, Bendori SO, Borenstein T, Aframian N, Kessel A, Eldar A. Arbitrium communication controls phage lysogeny through non-lethal modulation of a host toxin-antitoxin defence system. Nat Microbiol 2024; 9:150-160. [PMID: 38177304 DOI: 10.1038/s41564-023-01551-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 11/07/2023] [Indexed: 01/06/2024]
Abstract
Temperate Bacillus phages often utilize arbitrium communication to control lysis/lysogeny decisions, but the mechanisms by which this control is exerted remains largely unknown. Here we find that the arbitrium system of Bacillus subtilis phage ϕ3T modulates the host-encoded MazEF toxin-antitoxin system to this aim. Upon infection, the MazF ribonuclease is activated by three phage genes. At low arbitrium signal concentrations, MazF is inactivated by two phage-encoded MazE homologues: the arbitrium-controlled AimX and the later-expressed YosL proteins. At high signal, MazF remains active, promoting lysogeny without harming the bacterial host. MazF cleavage sites are enriched on transcripts of phage lytic genes but absent from the phage repressor in ϕ3T and other Spβ-like phages. Combined with low activation levels of MazF during infections, this pattern explains the phage-specific effect. Our results show how a bacterial toxin-antitoxin system has been co-opted by a phage to control lysis/lysogeny decisions without compromising host viability.
Collapse
Affiliation(s)
- Polina Guler
- Shmunis School of Biomedicine and Cancer Research, Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv, Israel
| | - Shira Omer Bendori
- Shmunis School of Biomedicine and Cancer Research, Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv, Israel
| | - Tom Borenstein
- Shmunis School of Biomedicine and Cancer Research, Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv, Israel
| | - Nitzan Aframian
- Shmunis School of Biomedicine and Cancer Research, Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv, Israel
| | - Amit Kessel
- Department of Biochemistry and Molecular Biology, Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv, Israel
| | - Avigdor Eldar
- Shmunis School of Biomedicine and Cancer Research, Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv, Israel.
| |
Collapse
|
10
|
Tang D, Chen Y, Chen H, Jia T, Chen Q, Yu Y. Multiple enzymatic activities of a Sir2-HerA system cooperate for anti-phage defense. Mol Cell 2023; 83:4600-4613.e6. [PMID: 38096825 DOI: 10.1016/j.molcel.2023.11.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 09/14/2023] [Accepted: 11/13/2023] [Indexed: 12/24/2023]
Abstract
In response to the persistent exposure to phage infection, bacteria have evolved diverse antiviral defense mechanisms. In this study, we report a bacterial two-component defense system consisting of a Sir2 NADase and a HerA helicase. Cryo-electron microscopy reveals that Sir2 and HerA assemble into a ∼1 MDa supramolecular octadecamer. Unexpectedly, this complex exhibits various enzymatic activities, including ATPase, NADase, helicase, and nuclease, which work together in a sophisticated manner to fulfill the antiphage function. Therefore, we name this defense system "Nezha" after a divine warrior in Chinese mythology who employs multiple weapons to defeat enemies. Our findings demonstrate that Nezha could sense phage infections, self-activate to arrest cell growth, eliminate phage genomes, and subsequently deactivate to allow for cell recovery. Collectively, Nezha represents a paradigm of sophisticated and multifaceted strategies bacteria use to defend against viral infections.
Collapse
Affiliation(s)
- Dongmei Tang
- Department of Urology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Yijun Chen
- Department of Biotherapy, Cancer Center and State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Hao Chen
- Department of Biotherapy, Cancer Center and State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Tingting Jia
- Department of Biotherapy, Cancer Center and State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Qiang Chen
- Department of Biotherapy, Cancer Center and State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, China.
| | - Yamei Yu
- Department of Biotherapy, Cancer Center and State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, China.
| |
Collapse
|
11
|
Rousset F. Innate immunity: the bacterial connection. Trends Immunol 2023; 44:945-953. [PMID: 37919213 DOI: 10.1016/j.it.2023.10.001] [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: 10/05/2023] [Revised: 10/07/2023] [Accepted: 10/07/2023] [Indexed: 11/04/2023]
Abstract
Pathogens have fueled the diversification of intracellular defense strategies that collectively define cell-autonomous innate immunity. In bacteria, innate immunity is manifested by a broad arsenal of defense systems that provide protection against bacterial viruses, called phages. The complexity of the bacterial immune repertoire has only been realized recently and is now suggesting that innate immunity has commonalities across the tree of life: many components of eukaryotic innate immunity are found in bacteria where they protect against phages, including the cGAS-STING pathway, gasdermins, and viperins. Here, I summarize recent findings on the conservation of innate immune pathways between prokaryotes and eukaryotes and hypothesize that bacterial defense mechanisms can catalyze the discovery of novel molecular players of eukaryotic innate immunity.
Collapse
Affiliation(s)
- François Rousset
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel.
| |
Collapse
|
12
|
Zhou WY, Wen H, Li YJ, Gao L, Rao SQ, Yang ZQ, Zhu GQ. Acquisition, loss, and replication of functional modules promote the genetic diversity of Salmonella bacteriophages. Microbiol Res 2023; 275:127461. [PMID: 37499310 DOI: 10.1016/j.micres.2023.127461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 07/13/2023] [Accepted: 07/13/2023] [Indexed: 07/29/2023]
Abstract
Owing to the threats that Salmonella poses to public health and the abuse of antimicrobials, bacteriophage therapy against Salmonella is experiencing a resurgence. Although several phages have been reported as safe and efficient for controlling Salmonella, the genetic diversity and relatedness among Salmonella phages remain poorly understood. In this study, whole-genome sequences of 91 Salmonella bacteriophages were obtained from the National Center for Biological Information genome database. Phylogenetic analysis, mosaic structure comparisons, gene content analysis, and orthologue group clustering were performed. Phylogenetic analysis revealed four singletons and two major lineages (I-II), including five subdividing clades, of which Salmonella phages belonging to morphologically distinct families were clustered in the same clade. Chimeric structures (n = 31), holin genes (n = 18), lysin genes (n = 66), DNA packaging genes (n = 55), and DNA metabolism genes (n = 24) were present in these phages. Moreover, phages from different subdivided clusters harboured distinct genes associated with host cell lysis, DNA packaging, and DNA metabolism. Notably, phages belonging to morphologically distinct families shared common orthologue groups. Although several functional modules of phages SS1 and SE16 shared > 99% nucleotide sequence identity with phages SI2 and SI23, the major differences between these phages were the absence and replication of functional modules. The data obtained herein revealed the genetic diversity of Salmonella phages at genomic, structural, and gene content levels. The genetic diversity of Salmonella phages is likely owing to the acquisition, loss, and replication of functional modules.
Collapse
Affiliation(s)
- Wen-Yuan Zhou
- College of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu 225127, China; College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, China
| | - Hua Wen
- College of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu 225127, China
| | - Ya-Jie Li
- College of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu 225127, China
| | - Lu Gao
- College of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu 225127, China
| | - Sheng-Qi Rao
- College of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu 225127, China
| | - Zhen-Quan Yang
- College of Food Science and Engineering, Yangzhou University, Yangzhou, Jiangsu 225127, China.
| | - Guo-Qiang Zhu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, China.
| |
Collapse
|
13
|
Georjon H, Bernheim A. The highly diverse antiphage defence systems of bacteria. Nat Rev Microbiol 2023; 21:686-700. [PMID: 37460672 DOI: 10.1038/s41579-023-00934-x] [Citation(s) in RCA: 43] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/15/2023] [Indexed: 09/14/2023]
Abstract
Bacteria and their viruses have coevolved for billions of years. This ancient and still ongoing arms race has led bacteria to develop a vast antiphage arsenal. The development of high-throughput screening methods expanded our knowledge of defence systems from a handful to more than a hundred systems, unveiling many different molecular mechanisms. These findings reveal that bacterial immunity is much more complex than previously thought. In this Review, we explore recently discovered bacterial antiphage defence systems, with a particular focus on their molecular diversity, and discuss the ecological and evolutionary drivers and implications of the existing diversity of antiphage defence mechanisms.
Collapse
Affiliation(s)
- Héloïse Georjon
- Molecular Diversity of Microbes Lab, Institut Pasteur, Université Paris Cité, INSERM, Paris, France
| | - Aude Bernheim
- Molecular Diversity of Microbes Lab, Institut Pasteur, Université Paris Cité, INSERM, Paris, France.
| |
Collapse
|
14
|
Ibarra‐Chávez R, Reboud J, Penadés JR, Cooper JM. Phage-Inducible Chromosomal Islands as a Diagnostic Platform to Capture and Detect Bacterial Pathogens. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2301643. [PMID: 37358000 PMCID: PMC10460865 DOI: 10.1002/advs.202301643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 06/06/2023] [Indexed: 06/27/2023]
Abstract
Phage-inducible chromosomal islands (PICIs) are a family of phage satellites that hijack phage components to facilitate their mobility and spread. Recently, these genetic constructs are repurposed as antibacterial drones, enabling a new toolbox for unorthodox applications in biotechnology. To illustrate a new suite of functions, the authors have developed a user-friendly diagnostic system, based upon PICI transduction to selectively enrich bacteria, allowing the detection and sequential recovery of Escherichia coli and Staphylococcus aureus. The system enables high transfer rates and sensitivities in comparison with phages, with detection down to ≈50 CFU mL-1 . In contrast to conventional detection strategies, which often rely on nucleic acid molecular assays, and cannot differentiate between dead and live organisms, this approach enables visual sensing of viable pathogens only, through the expression of a reporter gene encoded in the PICI. The approach extends diagnostic sensing mechanisms beyond cell-free synthetic biology strategies, enabling new synthetic biology/biosensing toolkits.
Collapse
Affiliation(s)
- Rodrigo Ibarra‐Chávez
- Department of BiologySection of MicrobiologyUniversity of CopenhagenUniversitetsparken 15, bldg. 1CopenhagenDK2100Denmark
- Institute of InfectionImmunity and InflammationCollege of MedicalVeterinary and Life SciencesUniversity of GlasgowGlasgowG12 8TAUK
- Division of Biomedical EngineeringJames Watt School of EngineeringUniversity of GlasgowGlasgowG12 8QQUK
| | - Julien Reboud
- Division of Biomedical EngineeringJames Watt School of EngineeringUniversity of GlasgowGlasgowG12 8QQUK
| | - José R. Penadés
- Institute of InfectionImmunity and InflammationCollege of MedicalVeterinary and Life SciencesUniversity of GlasgowGlasgowG12 8TAUK
- Departamento de Ciencias BiomédicasUniversidad CEU Cardenal HerreraMoncada46113Spain
- Centre for Bacterial Resistance BiologyImperial College LondonSouth KensingtonSW7 2AZUK
| | - Jonathan M. Cooper
- Division of Biomedical EngineeringJames Watt School of EngineeringUniversity of GlasgowGlasgowG12 8QQUK
| |
Collapse
|
15
|
Georjon H, Tesson F, Shomar H, Bernheim A. Genomic characterization of the antiviral arsenal of Actinobacteria. MICROBIOLOGY (READING, ENGLAND) 2023; 169:001374. [PMID: 37531269 PMCID: PMC10482375 DOI: 10.1099/mic.0.001374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 07/18/2023] [Indexed: 08/04/2023]
Abstract
Phages are ubiquitous in nature, and bacteria with very different genomics, metabolisms, and lifestyles are subjected to their predation. Yet, the defence systems that allow bacteria to resist their phages have rarely been explored experimentally outside a very limited number of model organisms. Actinobacteria (Actinomycetota) are a phylum of GC-rich Gram-positive bacteria, which often produce an important diversity of secondary metabolites. Despite being ubiquitous in a wide range of environments, from soil to fresh and sea water but also the gut microbiome, relatively little is known about the anti-phage arsenal of Actinobacteria. In this work, we used DefenseFinder to systematically detect 131 anti-phage defence systems in 22803 fully sequenced prokaryotic genomes, among which are 2253 Actinobacteria of more than 700 species. We show that, like other bacteria, Actinobacteria encode many diverse anti-phage systems that are often encoded on mobile genetic elements. We further demonstrate that most detected defence systems are absent or rarer in Actinobacteria than in other bacteria, while a few rare systems are enriched (notably gp29-gp30 and Wadjet). We characterize the spatial distribution of anti-phage systems on Streptomyces chromosomes and show that some defence systems (e.g. RM systems) tend to be encoded in the core region, while others (e.g. Lamassu and Wadjet) are enriched towards the extremities. Overall, our results suggest that Actinobacteria might be a source of novel anti-phage systems and provide clues to characterize mechanistic aspects of known anti-phage systems.
Collapse
Affiliation(s)
- Héloïse Georjon
- Molecular Diversity of Microbes Lab, Institut Pasteur, Université Paris Cité, Inserm U1284, Paris, France
| | - Florian Tesson
- Molecular Diversity of Microbes Lab, Institut Pasteur, Université Paris Cité, Inserm U1284, Paris, France
- UMR 1137, IAME, Université de Paris, INSERM, Paris, France
| | - Helena Shomar
- Molecular Diversity of Microbes Lab, Institut Pasteur, Université Paris Cité, Inserm U1284, Paris, France
| | - Aude Bernheim
- Molecular Diversity of Microbes Lab, Institut Pasteur, Université Paris Cité, Inserm U1284, Paris, France
| |
Collapse
|
16
|
Rousset F, Sorek R. The evolutionary success of regulated cell death in bacterial immunity. Curr Opin Microbiol 2023; 74:102312. [PMID: 37030143 DOI: 10.1016/j.mib.2023.102312] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 03/08/2023] [Accepted: 03/09/2023] [Indexed: 04/09/2023]
Abstract
Bacteria employ a complex arsenal of immune mechanisms to defend themselves against phages. Recent studies demonstrate that these immune mechanisms frequently involve regulated cell death in response to phage infection. By sacrificing infected cells, this strategy prevents the spread of phages within the surrounding population. In this review, we discuss the principles of regulated cell death in bacterial defense, and show that over 70% of sequenced prokaryotes employ this strategy as part of their defensive arsenals. We highlight the modularity of defense systems involving regulated cell death, explaining how shuffling between phage-sensing and cell-killing protein domains dominates their evolution. Some of these defense systems are the evolutionary ancestors of key components of eukaryotic immunity, highlighting their importance in shaping the evolutionary trajectory of immune systems across the tree of life.
Collapse
|
17
|
Nicholas-Haizelden K, Murphy B, Hoptroff M, Horsburgh MJ. Bioprospecting the Skin Microbiome: Advances in Therapeutics and Personal Care Products. Microorganisms 2023; 11:1899. [PMID: 37630459 PMCID: PMC10456854 DOI: 10.3390/microorganisms11081899] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 07/20/2023] [Accepted: 07/25/2023] [Indexed: 08/27/2023] Open
Abstract
Bioprospecting is the discovery and exploration of biological diversity found within organisms, genetic elements or produced compounds with prospective commercial or therapeutic applications. The human skin is an ecological niche which harbours a rich and compositional diversity microbiome stemming from the multifactorial interactions between the host and microbiota facilitated by exploitable effector compounds. Advances in the understanding of microbial colonisation mechanisms alongside species and strain interactions have revealed a novel chemical and biological understanding which displays applicative potential. Studies elucidating the organismal interfaces and concomitant understanding of the central processes of skin biology have begun to unravel a potential wealth of molecules which can exploited for their proposed functions. A variety of skin-microbiome-derived compounds display prospective therapeutic applications, ranging from antioncogenic agents relevant in skin cancer therapy to treatment strategies for antimicrobial-resistant bacterial and fungal infections. Considerable opportunities have emerged for the translation to personal care products, such as topical agents to mitigate various skin conditions such as acne and eczema. Adjacent compound developments have focused on cosmetic applications such as reducing skin ageing and its associated changes to skin properties and the microbiome. The skin microbiome contains a wealth of prospective compounds with therapeutic and commercial applications; however, considerable work is required for the translation of in vitro findings to relevant in vivo models to ensure translatability.
Collapse
Affiliation(s)
- Keir Nicholas-Haizelden
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool L69 3BX, UK;
| | - Barry Murphy
- Unilever Research & Development, Port Sunlight, Wirral CH63 3JW, UK; (B.M.); (M.H.)
| | - Michael Hoptroff
- Unilever Research & Development, Port Sunlight, Wirral CH63 3JW, UK; (B.M.); (M.H.)
| | - Malcolm J. Horsburgh
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool L69 3BX, UK;
| |
Collapse
|
18
|
Mariano G, Blower TR. Conserved domains can be found across distinct phage defence systems. Mol Microbiol 2023; 120:45-53. [PMID: 36840376 PMCID: PMC10952713 DOI: 10.1111/mmi.15047] [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: 01/05/2023] [Revised: 02/15/2023] [Accepted: 02/16/2023] [Indexed: 02/26/2023]
Abstract
Bacteria are continuously exposed to predation from bacteriophages (phages) and, in response, have evolved a broad range of defence systems. These systems can prevent the replication of phages and other mobile genetic elements (MGE). Defence systems are often encoded together in genomic loci defined as "defence islands", a tendency that has been extensively exploited to identify novel antiphage systems. In the last few years, >100 new antiphage systems have been discovered, and some display homology to components of the immune systems of plants and animals. In many instances, prediction tools have found domains with similar predicted functions present as different combinations within distinct antiphage systems. In this Perspective Article, we review recent reports describing the discovery and the predicted domain composition of several novel antiphage systems. We discuss several examples of similar protein domains adopted by different antiphage systems, including domains of unknown function (DUFs), domains involved in nucleic acid recognition and degradation, and domains involved in NAD+ depletion. We further discuss the potential evolutionary advantages that could have driven the independent acquisition of these domains by different antiphage systems.
Collapse
Affiliation(s)
- Giuseppina Mariano
- Microbes in Health and Disease Theme, Newcastle University Biosciences InstituteNewcastle UniversityNewcastle upon TyneUK
| | | |
Collapse
|
19
|
Mayo-Muñoz D, Pinilla-Redondo R, Birkholz N, Fineran PC. A host of armor: Prokaryotic immune strategies against mobile genetic elements. Cell Rep 2023; 42:112672. [PMID: 37347666 DOI: 10.1016/j.celrep.2023.112672] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 05/22/2023] [Accepted: 06/02/2023] [Indexed: 06/24/2023] Open
Abstract
Prokaryotic adaptation is strongly influenced by the horizontal acquisition of beneficial traits via mobile genetic elements (MGEs), such as viruses/bacteriophages and plasmids. However, MGEs can also impose a fitness cost due to their often parasitic nature and differing evolutionary trajectories. In response, prokaryotes have evolved diverse immune mechanisms against MGEs. Recently, our understanding of the abundance and diversity of prokaryotic immune systems has greatly expanded. These defense systems can degrade the invading genetic material, inhibit genome replication, or trigger abortive infection, leading to population protection. In this review, we highlight these strategies, focusing on the most recent discoveries. The study of prokaryotic defenses not only sheds light on microbial evolution but also uncovers novel enzymatic activities with promising biotechnological applications.
Collapse
Affiliation(s)
- David Mayo-Muñoz
- Department of Microbiology and Immunology, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; Genetics Otago, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
| | - Rafael Pinilla-Redondo
- Department of Microbiology and Immunology, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; Section of Microbiology, University of Copenhagen, Universitetsparken 15, 2100 Copenhagen, Denmark
| | - Nils Birkholz
- Department of Microbiology and Immunology, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; Genetics Otago, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; Bioprotection Aotearoa, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
| | - Peter C Fineran
- Department of Microbiology and Immunology, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; Genetics Otago, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; Bioprotection Aotearoa, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand.
| |
Collapse
|
20
|
Johnson MC, Laderman E, Huiting E, Zhang C, Davidson A, Bondy-Denomy J. Core defense hotspots within Pseudomonas aeruginosa are a consistent and rich source of anti-phage defense systems. Nucleic Acids Res 2023; 51:4995-5005. [PMID: 37140042 PMCID: PMC10250203 DOI: 10.1093/nar/gkad317] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 04/07/2023] [Accepted: 04/13/2023] [Indexed: 05/05/2023] Open
Abstract
Bacteria use a diverse arsenal of anti-phage immune systems, including CRISPR-Cas and restriction enzymes. Recent advances in anti-phage system discovery and annotation tools have unearthed many unique systems, often encoded in horizontally transferred defense islands, which can be horizontally transferred. Here, we developed Hidden Markov Models (HMMs) for defense systems and queried microbial genomes on the NCBI database. Out of the 30 species with >200 completely sequenced genomes, our analysis found Pseudomonas aeruginosa exhibits the greatest diversity of anti-phage systems, as measured by Shannon entropy. Using network analysis to identify the common neighbors of anti-phage systems, we identified two core defense hotspot loci (cDHS1 and cDHS2). cDHS1 is up to 224 kb (median: 26 kb) with varied arrangements of more than 30 distinct immune systems across isolates, while cDHS2 has 24 distinct systems (median: 6 kb). Both cDHS regions are occupied in a majority of P. aeruginosa isolates. Most cDHS genes are of unknown function potentially representing new anti-phage systems, which we validated by identifying a novel anti-phage system (Shango) commonly encoded in cDHS1. Identifying core genes flanking immune islands could simplify immune system discovery and may represent popular landing spots for diverse MGEs carrying anti-phage systems.
Collapse
Affiliation(s)
- Matthew C Johnson
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Eric Laderman
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Erin Huiting
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Chi Zhang
- Departments of Biochemistry and Molecular Genetics, University of Toronto, 661 University Ave, Toronto, ON M5G 1M1, Canada
| | - Alan Davidson
- Departments of Biochemistry and Molecular Genetics, University of Toronto, 661 University Ave, Toronto, ON M5G 1M1, Canada
| | - Joseph Bondy-Denomy
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94158, USA
- Quantitative Biosciences Institute, University of California, San Francisco, San Francisco, CA 94158, USA
- Innovative Genomics Institute, Berkeley, CA 94720, USA
| |
Collapse
|
21
|
Macdonald E, Wright R, Connolly JPR, Strahl H, Brockhurst M, van Houte S, Blower TR, Palmer T, Mariano G. The novel anti-phage system Shield co-opts an RmuC domain to mediate phage defense across Pseudomonas species. PLoS Genet 2023; 19:e1010784. [PMID: 37276233 DOI: 10.1371/journal.pgen.1010784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 05/12/2023] [Indexed: 06/07/2023] Open
Abstract
Competitive bacteria-bacteriophage interactions have resulted in the evolution of a plethora of bacterial defense systems preventing phage propagation. In recent years, computational and bioinformatic approaches have underpinned the discovery of numerous novel bacterial defense systems. Anti-phage systems are frequently encoded together in genomic loci termed defense islands. Here we report the identification and characterisation of a novel anti-phage system, that we have termed Shield, which forms part of the Pseudomonas defensive arsenal. The Shield system comprises the core component ShdA, a membrane-bound protein harboring an RmuC domain. Heterologous production of ShdA alone is sufficient to mediate bacterial immunity against several phages. We demonstrate that Shield and ShdA confer population-level immunity and that they can also decrease transformation efficiency. We further show that ShdA homologues can degrade DNA in vitro and, when expressed in a heterologous host, can alter the organisation of the host chromosomal DNA. Use of comparative genomic approaches identified how Shield can be divided into four subtypes, three of which contain additional components that in some cases can negatively affect the activity of ShdA and/or provide additional lines of phage defense. Collectively, our results identify a new player within the Pseudomonas bacterial immunity arsenal that displays a novel mechanism of protection, and reveals a role for RmuC domains in phage defense.
Collapse
Affiliation(s)
- Elliot Macdonald
- Microbes in Health and Disease Theme, Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Rosanna Wright
- Division of Evolution, Infection and Genomics, School of Biological Sciences, University of Manchester, Manchester, United Kingdom
| | - James P R Connolly
- Microbes in Health and Disease Theme, Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Henrik Strahl
- Centre for Bacterial Cell Biology, Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Michael Brockhurst
- Division of Evolution, Infection and Genomics, School of Biological Sciences, University of Manchester, Manchester, United Kingdom
| | - Stineke van Houte
- Environment and Sustainability Institute, University of Exeter, Penryn Campus, Penryn, Cornwall, United Kingdom
| | - Tim R Blower
- Department of Biosciences, Durham University, Stockton Road, Durham, United Kingdom
| | - Tracy Palmer
- Microbes in Health and Disease Theme, Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Giuseppina Mariano
- Microbes in Health and Disease Theme, Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| |
Collapse
|
22
|
Boyle TA, Hatoum-Aslan A. Recurring and emerging themes in prokaryotic innate immunity. Curr Opin Microbiol 2023; 73:102324. [PMID: 37163858 PMCID: PMC10360293 DOI: 10.1016/j.mib.2023.102324] [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: 02/02/2023] [Revised: 04/06/2023] [Accepted: 04/07/2023] [Indexed: 05/12/2023]
Abstract
A resurgence of interest in the pathways that bacteria use to protect against their viruses (i.e. phages) has led to the discovery of dozens of new antiphage defenses. Given the sheer abundance and diversity of phages - the ever-evolving targets of immunity - it is not surprising that these newly described defenses are also remarkably diverse. However, as their mechanisms slowly come into focus, some common strategies and themes are also beginning to emerge. This review highlights recurring and emerging themes in the mechanisms of innate immunity in bacteria and archaea, with an emphasis on recently described systems that have undergone more thorough mechanistic characterization.
Collapse
Affiliation(s)
- Tori A Boyle
- University of Illinois at Urbana-Champaign, Department of Microbiology, Urbana, IL 61801, USA
| | - Asma Hatoum-Aslan
- University of Illinois at Urbana-Champaign, Department of Microbiology, Urbana, IL 61801, USA.
| |
Collapse
|
23
|
Silpe JE, Duddy OP, Bassler BL. Induction mechanisms and strategies underlying interprophage competition during polylysogeny. PLoS Pathog 2023; 19:e1011363. [PMID: 37200239 DOI: 10.1371/journal.ppat.1011363] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/20/2023] Open
Affiliation(s)
- Justin E Silpe
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America
- Howard Hughes Medical Institute, Chevy Chase, Maryland, United States of America
| | - Olivia P Duddy
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America
| | - Bonnie L Bassler
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America
- Howard Hughes Medical Institute, Chevy Chase, Maryland, United States of America
| |
Collapse
|
24
|
Patel PH, Maxwell KL. Prophages provide a rich source of antiphage defense systems. Curr Opin Microbiol 2023; 73:102321. [PMID: 37121062 DOI: 10.1016/j.mib.2023.102321] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 03/26/2023] [Accepted: 03/27/2023] [Indexed: 05/02/2023]
Abstract
Temperate phages are pervasive in nature, existing within bacterial cells in a form known as prophages. In this state, survival of the phage is intricately tied to the survival of the bacterial host. As a result, prophages often encode genes that increase bacterial fitness. One important way to increase survival is to provide defense against competing phages. Recent work reviewed here reveals that prophages provide a diverse and robust reservoir of antiphage defense systems that likely play a major role in bacterial-phage dynamics.
Collapse
Affiliation(s)
- Pramalkumar H Patel
- Department of Biochemistry, University of Toronto, MaRS West Tower, 661 University Avenue, Toronto, ON M5G 1M1, Canada
| | - Karen L Maxwell
- Department of Biochemistry, University of Toronto, MaRS West Tower, 661 University Avenue, Toronto, ON M5G 1M1, Canada.
| |
Collapse
|
25
|
Moura de Sousa J, Lourenço M, Gordo I. Horizontal gene transfer among host-associated microbes. Cell Host Microbe 2023; 31:513-527. [PMID: 37054673 DOI: 10.1016/j.chom.2023.03.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/15/2023]
Abstract
Horizontal gene transfer is an important evolutionary force, facilitating bacterial diversity. It is thought to be pervasive in host-associated microbiomes, where bacterial densities are high and mobile elements are frequent. These genetic exchanges are also key for the rapid dissemination of antibiotic resistance. Here, we review recent studies that have greatly extended our knowledge of the mechanisms underlying horizontal gene transfer, the ecological complexities of a network of interactions involving bacteria and their mobile elements, and the effect of host physiology on the rates of genetic exchanges. Furthermore, we discuss other, fundamental challenges in detecting and quantifying genetic exchanges in vivo, and how studies have contributed to start overcoming these challenges. We highlight the importance of integrating novel computational approaches and theoretical models with experimental methods where multiple strains and transfer elements are studied, both in vivo and in controlled conditions that mimic the intricacies of host-associated environments.
Collapse
Affiliation(s)
- Jorge Moura de Sousa
- Institut Pasteur, Université Paris Cité, CNRS, UMR3525, Microbial Evolutionary Genomics, Paris, 75015 Paris, France
| | - Marta Lourenço
- Institut Pasteur, Université Paris Cité, Biodiversity and Epidemiology of Bacterial Pathogens, F-75015 Paris, France
| | - Isabel Gordo
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande,6, Oeiras, Portugal.
| |
Collapse
|
26
|
Hossain M, Aslan B, Hatoum-Aslan A. Tandem mobilization of anti-phage defenses alongside SCC mec cassettes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.17.533233. [PMID: 36993521 PMCID: PMC10055296 DOI: 10.1101/2023.03.17.533233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Bacterial viruses (phages) and the immune systems targeted against them significantly impact bacterial survival, evolution, and the emergence of pathogenic strains. While recent research has made spectacular strides towards discovering and validating new defenses in a few model organisms1-3, the inventory of immune systems in clinically-relevant bacteria remains underexplored, and little is known about the mechanisms by which these systems horizontally spread. Such pathways not only impact the evolutionary trajectory of bacterial pathogens, but also threaten to undermine the effectiveness of phage-based therapeutics. Here, we investigate the battery of defenses in staphylococci, opportunistic pathogens that constitute leading causes of antibiotic-resistant infections. We show that these organisms harbor a variety of anti-phage defenses encoded within/near the infamous SCC (staphylococcal cassette chromosome) mec cassettes, mobile genomic islands that confer methicillin resistance. Importantly, we demonstrate that SCCmec-encoded recombinases mobilize not only SCCmec, but also tandem cassettes enriched with diverse defenses. Further, we show that phage infection potentiates cassette mobilization. Taken together, our findings reveal that beyond spreading antibiotic resistance, SCCmec cassettes play a central role in disseminating anti-phage defenses. This work underscores the urgent need for developing adjunctive treatments that target this pathway to save the burgeoning phage therapeutics from suffering the same fate as conventional antibiotics.
Collapse
Affiliation(s)
- Motaher Hossain
- University of Illinois at Urbana-Champaign, Department of Microbiology, Urbana, IL, USA
| | - Barbaros Aslan
- University of Illinois at Urbana-Champaign, Department of Microbiology, Urbana, IL, USA
| | - Asma Hatoum-Aslan
- University of Illinois at Urbana-Champaign, Department of Microbiology, Urbana, IL, USA
| |
Collapse
|
27
|
Horne T, Orr VT, Hall JP. How do interactions between mobile genetic elements affect horizontal gene transfer? Curr Opin Microbiol 2023; 73:102282. [PMID: 36863168 DOI: 10.1016/j.mib.2023.102282] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/20/2023] [Accepted: 01/24/2023] [Indexed: 03/03/2023]
Abstract
Horizontal gene transfer is central to bacterial adaptation and is facilitated by mobile genetic elements (MGEs). Increasingly, MGEs are being studied as agents with their own interests and adaptations, and the interactions MGEs have with one another are recognised as having a powerful effect on the flow of traits between microbes. Collaborations and conflicts between MGEs are nuanced and can both promote and inhibit the acquisition of new genetic material, shaping the maintenance of newly acquired genes and the dissemination of important adaptive traits through microbiomes. We review recent studies that shed light on this dynamic and oftentimes interlaced interplay, highlighting the importance of genome defence systems in mediating MGE-MGE conflicts, and outlining the consequences for evolutionary change, that resonate from the molecular to microbiome and ecosystem levels.
Collapse
Affiliation(s)
- Tanya Horne
- Department of Evolution, Ecology and Behaviour, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Crown Street, Liverpool L69 7ZB, United Kingdom
| | - Victoria T Orr
- Department of Evolution, Ecology and Behaviour, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Crown Street, Liverpool L69 7ZB, United Kingdom
| | - James Pj Hall
- Department of Evolution, Ecology and Behaviour, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Crown Street, Liverpool L69 7ZB, United Kingdom.
| |
Collapse
|
28
|
Disarm The Bacteria: What Temperate Phages Can Do. Curr Issues Mol Biol 2023; 45:1149-1167. [PMID: 36826021 PMCID: PMC9955262 DOI: 10.3390/cimb45020076] [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: 12/28/2022] [Revised: 01/28/2023] [Accepted: 01/29/2023] [Indexed: 02/04/2023] Open
Abstract
In the field of phage applications and clinical treatment, virulent phages have been in the spotlight whereas temperate phages received, relatively speaking, less attention. The fact that temperate phages often carry virulent or drug-resistant genes is a constant concern and drawback in temperate phage applications. However, temperate phages also play a role in bacterial regulation. This review elucidates the biological properties of temperate phages based on their life cycle and introduces the latest work on temperate phage applications, such as on host virulence reduction, biofilm degradation, genetic engineering and phage display. The versatile use of temperate phages coupled with their inherent properties, such as economy, ready accessibility, wide variety and host specificity, make temperate phages a solid candidate in tackling bacterial infections.
Collapse
|
29
|
Schmidt AK, Faith DR, Secor PR. PICI thieves: Molecular piracy and cooperation. Cell Host Microbe 2023; 31:3-5. [PMID: 36634621 DOI: 10.1016/j.chom.2022.12.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Phage-inducible chromosomal islands (PICIs) steal structural proteins from helper phages. In two related studies, Penadés and coworkers reveal that PICIs are not parasites but mutualists. Some PICIs mobilize defense systems that restrict niche competitors, while other PICIs encode their own capsids and steal helper phage tails without affecting their fitness.
Collapse
Affiliation(s)
- Amelia K Schmidt
- Cell, Molecular, and Microbial Biology Graduate Program, Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
| | - Dominick R Faith
- Cell, Molecular, and Microbial Biology Graduate Program, Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
| | - Patrick R Secor
- Cell, Molecular, and Microbial Biology Graduate Program, Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA.
| |
Collapse
|
30
|
Alqurainy N, Miguel-Romero L, Moura de Sousa J, Chen J, Rocha EPC, Fillol-Salom A, Penadés JR. A widespread family of phage-inducible chromosomal islands only steals bacteriophage tails to spread in nature. Cell Host Microbe 2023; 31:69-82.e5. [PMID: 36596306 DOI: 10.1016/j.chom.2022.12.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 10/06/2022] [Accepted: 12/01/2022] [Indexed: 01/03/2023]
Abstract
Phage satellites are genetic elements that couple their life cycle to that of helper phages they parasitize, interfering with phage packaging through the production of small capsids, where only satellites are packaged. So far, in all analyzed systems, the satellite-sized capsids are composed of phage proteins. Here, we report that a family of phage-inducible chromosomal islands (PICIs), a type of satellites, encodes all the proteins required for both the production of small-sized capsids and the exclusive packaging of the PICIs into these capsids. Therefore, this new family, named capsid-forming PICIs (cf-PICIs), only requires phage tails to generate PICI particles. Remarkably, the representative cf-PICIs are produced with no cost from their helper phages, suggesting that the relationship between these elements is not parasitic. Finally, our phylogenomic studies indicate that cf-PICIs are present both in gram-positive and gram-negative bacteria and have evolved at least three times independently to spread in nature.
Collapse
Affiliation(s)
- Nasser Alqurainy
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8TA, UK; Department of Basic Science, College of Science and Health Professions, King Saud bin Abdulaziz University for Health Sciences, Riyadh 11426, Saudi Arabia
| | - Laura Miguel-Romero
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8TA, UK; Centre for Bacterial Resistance Biology, Imperial College London, London SW7 2AZ, UK
| | - Jorge Moura de Sousa
- Institut Pasteur, Université de Paris Cité, CNRS, UMR3525, Microbial Evolutionary Genomics, 75015 Paris, France
| | - John Chen
- Department of Microbiology and Immunology, Infectious Diseases Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore
| | - Eduardo P C Rocha
- Institut Pasteur, Université de Paris Cité, CNRS, UMR3525, Microbial Evolutionary Genomics, 75015 Paris, France
| | - Alfred Fillol-Salom
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8TA, UK; Centre for Bacterial Resistance Biology, Imperial College London, London SW7 2AZ, UK.
| | - José R Penadés
- Centre for Bacterial Resistance Biology, Imperial College London, London SW7 2AZ, UK; Universidad CEU Cardenal Herrera, CEU Universities, Valencia 46115, Spain.
| |
Collapse
|
31
|
Conrad B, Iseli C, Pirovino M. Energy-harnessing problem solving of primordial life: Modeling the emergence of catalytic host-nested parasite life cycles. PLoS One 2023; 18:e0281661. [PMID: 36972235 PMCID: PMC10042343 DOI: 10.1371/journal.pone.0281661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 01/29/2023] [Indexed: 03/29/2023] Open
Abstract
All life forms on earth ultimately descended from a primordial population dubbed the last universal common ancestor or LUCA via Darwinian evolution. Extant living systems share two salient functional features, a metabolism extracting and transforming energy required for survival, and an evolvable, informational polymer-the genome-conferring heredity. Genome replication invariably generates essential and ubiquitous genetic parasites. Here we model the energetic, replicative conditions of LUCA-like organisms and their parasites, as well as adaptive problem solving of host-parasite pairs. We show using an adapted Lotka-Volterra frame-work that three host-parasite pairs-individually a unit of a host and a parasite that is itself parasitized, therefore a nested parasite pair-are sufficient for robust and stable homeostasis, forming a life cycle. This nested parasitism model includes competition and habitat restriction. Its catalytic life cycle efficiently captures, channels and transforms energy, enabling dynamic host survival and adaptation. We propose a Malthusian fitness model for a quasispecies evolving through a host-nested parasite life cycle with two core features, rapid replacement of degenerate parasites and increasing evolutionary stability of host-nested parasite units from one to three pairs.
Collapse
Affiliation(s)
| | - Christian Iseli
- Bioinformatics Competence Center, EPFL and Unil, Lausanne, Switzerland
| | - Magnus Pirovino
- OPIRO Consulting Ltd, Triesen, Principality of Liechtenstein
| |
Collapse
|
32
|
When bacteria are phage playgrounds: interactions between viruses, cells, and mobile genetic elements. Curr Opin Microbiol 2022; 70:102230. [PMID: 36335712 DOI: 10.1016/j.mib.2022.102230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 09/23/2022] [Accepted: 10/06/2022] [Indexed: 11/06/2022]
Abstract
Studies of viral adaptation have focused on the selective pressures imposed by hosts. However, there is increasing evidence that interactions between viruses, cells, and other mobile genetic elements are determinant to the success of infections. These interactions are often associated with antagonism and competition, but sometimes involve cooperation or parasitism. We describe two key types of interactions - defense systems and genetic regulation - that allow the partners of the interaction to destroy or control the others. These interactions evolve rapidly by genetic exchanges, including among competing partners. They are sometimes followed by functional diversification. Gene exchanges also facilitate the emergence of cross-talk between elements in the same bacterium. In the end, these processes produce multilayered networks of interactions that shape the outcome of viral infections.
Collapse
|
33
|
Shi X, Zarkan A. Bacterial survivors: evaluating the mechanisms of antibiotic persistence. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 36748698 DOI: 10.1099/mic.0.001266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Bacteria withstand antibiotic onslaughts by employing a variety of strategies, one of which is persistence. Persistence occurs in a bacterial population where a subpopulation of cells (persisters) survives antibiotic treatment and can regrow in a drug-free environment. Persisters may cause the recalcitrance of infectious diseases and can be a stepping stone to antibiotic resistance, so understanding persistence mechanisms is critical for therapeutic applications. However, current understanding of persistence is pervaded by paradoxes that stymie research progress, and many aspects of this cellular state remain elusive. In this review, we summarize the putative persister mechanisms, including toxin-antitoxin modules, quorum sensing, indole signalling and epigenetics, as well as the reasons behind the inconsistent body of evidence. We highlight present limitations in the field and underscore a clinical context that is frequently neglected, in the hope of supporting future researchers in examining clinically important persister mechanisms.
Collapse
Affiliation(s)
- Xiaoyi Shi
- Cambridge Centre for International Research, Cambridge CB4 0PZ, UK
| | - Ashraf Zarkan
- Department of Genetics, University of Cambridge, Cambridge CB2 3EH, UK
| |
Collapse
|
34
|
Chevallereau A, Westra ER. Bacterial immunity: Mobile genetic elements are hotspots for defence systems. Curr Biol 2022; 32:R923-R926. [PMID: 36099898 DOI: 10.1016/j.cub.2022.07.075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A new study reports that phage-inducible chromosomal islands (PICIs) are hotspots of defence systems against phages, other PICIs and plasmids. This discovery highlights how competition between mobile genetic elements shapes bacterial defence gene repertoires and helps to better understand how defence systems are exchanged among bacteria.
Collapse
Affiliation(s)
- Anne Chevallereau
- Université Paris Cité, CNRS, INSERM, Institut Cochin, F-75014 Paris, France.
| | - Edze R Westra
- Environment and Sustainability Institute, Biosciences, University of Exeter, Penryn, UK.
| |
Collapse
|