1
|
Gerdes K. Diverse genetic contexts of HicA toxin domains propose a role in anti-phage defense. mBio 2024; 15:e0329323. [PMID: 38236063 PMCID: PMC10865869 DOI: 10.1128/mbio.03293-23] [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] [Received: 12/08/2023] [Accepted: 12/11/2023] [Indexed: 01/19/2024] Open
Abstract
Toxin-antitoxin (TA) modules are prevalent in prokaryotic genomes, often in substantial numbers. For instance, the Mycobacterium tuberculosis genome alone harbors close to 100 TA modules, half of which belong to a singular type. Traditionally ascribed multiple biological roles, recent insights challenge these notions and instead indicate a predominant function in phage defense. TAs are often located within Defense Islands, genomic regions that encode various defense systems. The analysis of genes within Defense Islands has unveiled a wide array of systems, including TAs that serve in anti-phage defense. Prokaryotic cells are equipped with anti-phage Viperins that, analogous to their mammalian counterparts, inhibit viral RNA transcription. Additionally, bacterial Structural Maintenance of Chromosome (SMC) proteins combat plasmid intrusion by recognizing foreign DNA signatures. This study undertakes a comprehensive bioinformatics analysis of genetic elements encoding the HicA double-stranded RNA-binding domain, complemented by protein structure modeling. The HicA toxin domains are found in at least 14 distinct contexts and thus exhibit a remarkable genetic diversity. Traditional bicistronic TA operons represent eight of these contexts, while four are characterized by monocistronic operons encoding fused HicA domains. Two contexts involve hicA adjacent to genes that encode bacterial Viperins. Notably, genes encoding RelE toxins are also adjacent to Viperin genes in some instances. This configuration hints at a synergistic enhancement of Viperin-mediated anti-phage action by HicA and RelE toxins. The discovery of a HicA domain merged with an SMC domain is compelling, prompting further investigation into its potential roles.IMPORTANCEProkaryotic organisms harbor a multitude of toxin-antitoxin (TA) systems, which have long puzzled scientists as "genes in search for a function." Recent scientific advancements have shed light on the primary role of TAs as anti-phage defense mechanisms. To gain an overview of TAs it is important to analyze their genetic contexts that can give hints on function and guide future experimental inquiries. This article describes a thorough bioinformatics examination of genes encoding the HicA toxin domain, revealing its presence in no fewer than 14 unique genetic arrangements. Some configurations notably align with anti-phage activities, underscoring potential roles in microbial immunity. These insights robustly reinforce the hypothesis that HicA toxins are integral components of the prokaryotic anti-phage defense repertoire. The elucidation of these genetic contexts not only advances our understanding of TAs but also contributes to a paradigm shift in how we perceive their functionality within the microbial world.
Collapse
Affiliation(s)
- Kenn Gerdes
- Kenn Gerdes is an independent researcher with the residence, Voldmestergade, Copenhagen, Denmark
| |
Collapse
|
2
|
Garcia-Rodriguez G, Girardin Y, Kumar Singh R, Volkov AN, Van Dyck J, Muruganandam G, Sobott F, Charlier D, Loris R. Toxin:antitoxin ratio sensing autoregulation of the Vibrio cholerae parDE2 module. SCIENCE ADVANCES 2024; 10:eadj2403. [PMID: 38181072 PMCID: PMC10776004 DOI: 10.1126/sciadv.adj2403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 12/04/2023] [Indexed: 01/07/2024]
Abstract
The parDE family of toxin-antitoxin (TA) operons is ubiquitous in bacterial genomes and, in Vibrio cholerae, is an essential component to maintain the presence of chromosome II. Here, we show that transcription of the V. cholerae parDE2 (VcparDE) operon is regulated in a toxin:antitoxin ratio-dependent manner using a molecular mechanism distinct from other type II TA systems. The repressor of the operon is identified as an assembly with a 6:2 stoichiometry with three interacting ParD2 dimers bridged by two ParE2 monomers. This assembly docks to a three-site operator containing 5'- GGTA-3' motifs. Saturation of this TA complex with ParE2 toxin results in disruption of the interface between ParD2 dimers and the formation of a TA complex of 2:2 stoichiometry. The latter is operator binding-incompetent as it is incompatible with the required spacing of the ParD2 dimers on the operator.
Collapse
Affiliation(s)
- Gabriela Garcia-Rodriguez
- Structural Biology Brussels, Department of Biotechnology, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium
- Structural Biology Research Center, Vlaams Instituut voor Biotechnologie, Pleinlaan 2, B-1050 Brussel, Belgium
| | - Yana Girardin
- Structural Biology Brussels, Department of Biotechnology, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium
- Structural Biology Research Center, Vlaams Instituut voor Biotechnologie, Pleinlaan 2, B-1050 Brussel, Belgium
| | - Ranjan Kumar Singh
- Structural Biology Brussels, Department of Biotechnology, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium
- Structural Biology Research Center, Vlaams Instituut voor Biotechnologie, Pleinlaan 2, B-1050 Brussel, Belgium
| | - Alexander N. Volkov
- Structural Biology Brussels, Department of Biotechnology, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium
- Structural Biology Research Center, Vlaams Instituut voor Biotechnologie, Pleinlaan 2, B-1050 Brussel, Belgium
- Jean Jeener NMR Centre, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium
| | - Jeroen Van Dyck
- Department of Chemistry, Universiteit Antwerpen, Groenenborgerlaan 171, Antwerpen 2020, Belgium
| | - Gopinath Muruganandam
- Structural Biology Brussels, Department of Biotechnology, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium
- Structural Biology Research Center, Vlaams Instituut voor Biotechnologie, Pleinlaan 2, B-1050 Brussel, Belgium
| | - Frank Sobott
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Daniel Charlier
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium
| | - Remy Loris
- Structural Biology Brussels, Department of Biotechnology, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium
- Structural Biology Research Center, Vlaams Instituut voor Biotechnologie, Pleinlaan 2, B-1050 Brussel, Belgium
| |
Collapse
|
3
|
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
|
4
|
Zamora-Caballero S, Chmielowska C, Quiles-Puchalt N, Brady A, Gallego Del Sol F, Mancheño-Bonillo J, Felipe-Ruíz A, Meijer WJJ, Penadés JR, Marina A. Antagonistic interactions between phage and host factors control arbitrium lysis-lysogeny decision. Nat Microbiol 2024; 9:161-172. [PMID: 38177302 PMCID: PMC10769878 DOI: 10.1038/s41564-023-01550-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 11/07/2023] [Indexed: 01/06/2024]
Abstract
Phages can use a small-molecule communication arbitrium system to coordinate lysis-lysogeny decisions, but the underlying mechanism remains unknown. Here we determined that the arbitrium system in Bacillus subtilis phage phi3T modulates the bacterial toxin-antitoxin system MazE-MazF to regulate the phage life cycle. We show that phi3T expresses AimX and YosL, which bind to and inactivate MazF. AimX also inhibits the function of phi3T_93, a protein that promotes lysogeny by binding to MazE and releasing MazF. Overall, these mutually exclusive interactions promote the lytic cycle of the phage. After several rounds of infection, the phage-encoded AimP peptide accumulates intracellularly and inactivates the phage antiterminator AimR, a process that eliminates aimX expression from the aimP promoter. Therefore, when AimP increases, MazF activity promotes reversion back to lysogeny, since AimX is absent. Altogether, our study reveals the evolutionary strategy used by arbitrium to control lysis-lysogeny by domesticating and fine-tuning a phage-defence mechanism.
Collapse
Grants
- Wellcome Trust
- Ministry of Economy and Competitiveness | Agencia Estatal de Investigación (Spanish Agencia Estatal de Investigación)
- Regional Government of Valencia | Conselleria d'Educació, Investigació, Cultura i Esport (Conselleria d'Educació, Investigació, Cultura i Esport de la Generalitat Valenciana)
- NYSE Euronext
- European Commission NextGenerationEU fund (EU 2020/2094), through CSIC’s Global Health Platform (PTI Salud Global). Block allocation group (BAG) DLS Proposal MX28394, ALBA Proposal 2020074406 and ESRF proposal MX-2452
- grants PID2019-108541GB-I00 and PID2022-137201NB-I00 from Spanish Government (Ministerio de Ciencia e Innovación), PROMETEO/2020/012 by Valencian Government
- MR/M003876/1, MR/V000772/1 and MR/S00940X/1 from the Medical Research Council (UK), BB/N002873/1, BB/V002376/1 and BB/S003835/1 from the Biotechnology and Biological Sciences Research Council (BBSRC, UK), ERC-ADG-2014 Proposal n° 670932 Dut-signal (from EU), and Wellcome Trust 201531/Z/16/Z
- RCUK | Biotechnology and Biological Sciences Research Council (BBSRC)
- RCUK | Medical Research Council (MRC)
- Wellcome Trust (Wellcome)
- EC | EU Framework Programme for Research and Innovation H2020 | H2020 Priority Excellent Science | H2020 European Research Council (H2020 Excellent Science - European Research Council)
Collapse
Affiliation(s)
- Sara Zamora-Caballero
- Instituto de Biomedicina de Valencia (IBV)-CSIC and CIBER de Enfermedades Raras (CIBERER)-ISCIII, Valencia, Spain
| | - Cora Chmielowska
- Centre for Bacterial Resistance Biology, Imperial College London, London, UK
| | - Nuria Quiles-Puchalt
- Centre for Bacterial Resistance Biology, Imperial College London, London, UK
- Department of Biomedical Sciences, Faculty of Health Sciences, Universidad CEU Cardenal Herrera, CEU Universities, Alfara del Patriarca, Spain
| | - Aisling Brady
- Centre for Bacterial Resistance Biology, Imperial College London, London, UK
- Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK
| | - Francisca Gallego Del Sol
- Instituto de Biomedicina de Valencia (IBV)-CSIC and CIBER de Enfermedades Raras (CIBERER)-ISCIII, Valencia, Spain
| | - Javier Mancheño-Bonillo
- Instituto de Biomedicina de Valencia (IBV)-CSIC and CIBER de Enfermedades Raras (CIBERER)-ISCIII, Valencia, Spain
| | - Alonso Felipe-Ruíz
- Instituto de Biomedicina de Valencia (IBV)-CSIC and CIBER de Enfermedades Raras (CIBERER)-ISCIII, Valencia, Spain
| | - Wilfried J J Meijer
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Universidad Autónoma, Cantoblanco, Madrid, Spain
| | - José R Penadés
- Centre for Bacterial Resistance Biology, Imperial College London, London, UK.
| | - Alberto Marina
- Instituto de Biomedicina de Valencia (IBV)-CSIC and CIBER de Enfermedades Raras (CIBERER)-ISCIII, Valencia, Spain.
| |
Collapse
|
5
|
Brady A, Cabello-Yeves E, Gallego Del Sol F, Chmielowska C, Mancheño-Bonillo J, Zamora-Caballero S, Omer SB, Torres-Puente M, Eldar A, Quiles-Puchalt N, Marina A, Penadés JR. Characterization of a unique repression system present in arbitrium phages of the SPbeta family. Cell Host Microbe 2023; 31:2023-2037.e8. [PMID: 38035880 DOI: 10.1016/j.chom.2023.11.003] [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: 04/04/2023] [Revised: 09/25/2023] [Accepted: 11/03/2023] [Indexed: 12/02/2023]
Abstract
Arbitrium-coding phages use peptides to communicate and coordinate the decision between lysis and lysogeny. However, the mechanism by which these phages establish lysogeny remains unknown. Here, focusing on the SPbeta phage family's model phages phi3T and SPβ, we report that a six-gene operon called the "SPbeta phages repressor operon" (sro) expresses not one but two master repressors, SroE and SroF, the latter of which folds like a classical phage integrase. To promote lysogeny, these repressors bind to multiple sites in the phage genome. SroD serves as an auxiliary repressor that, with SroEF, forms the repression module necessary for lysogeny establishment and maintenance. Additionally, the proteins SroABC within the operon are proposed to constitute the transducer module, connecting the arbitrium communication system to the activity of the repression module. Overall, this research sheds light on the intricate and specialized repression system employed by arbitrium SPβ-like phages in making lysis-lysogeny decisions.
Collapse
Affiliation(s)
- Aisling Brady
- Centre for Bacterial Resistance Biology, Imperial College London, London SW7 2AZ, UK; Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow G12 8TA, UK
| | - Elena Cabello-Yeves
- Instituto de Biomedicina de Valencia (IBV-CSIC), 46010 Valencia, Spain; CIBER de Enfermedades Raras (CIBERER), 46010 Valencia, Spain
| | - Francisca Gallego Del Sol
- Instituto de Biomedicina de Valencia (IBV-CSIC), 46010 Valencia, Spain; CIBER de Enfermedades Raras (CIBERER), 46010 Valencia, Spain
| | - Cora Chmielowska
- Centre for Bacterial Resistance Biology, Imperial College London, London SW7 2AZ, UK
| | - Javier Mancheño-Bonillo
- Instituto de Biomedicina de Valencia (IBV-CSIC), 46010 Valencia, Spain; CIBER de Enfermedades Raras (CIBERER), 46010 Valencia, Spain
| | - Sara Zamora-Caballero
- Instituto de Biomedicina de Valencia (IBV-CSIC), 46010 Valencia, Spain; CIBER de Enfermedades Raras (CIBERER), 46010 Valencia, Spain
| | - Shira Bendori Omer
- Shmunis School of Biomedicine and Cancer Research, 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
| | - Nuria Quiles-Puchalt
- Centre for Bacterial Resistance Biology, Imperial College London, London SW7 2AZ, UK; Department of Biomedical Sciences, Faculty of Health Sciences, Universidad CEU Cardenal Herrera, CEU Universities, Alfara del Patriarca 46115, Spain
| | - Alberto Marina
- Instituto de Biomedicina de Valencia (IBV-CSIC), 46010 Valencia, Spain; CIBER de Enfermedades Raras (CIBERER), 46010 Valencia, Spain.
| | - José R Penadés
- Centre for Bacterial Resistance Biology, Imperial College London, London SW7 2AZ, UK.
| |
Collapse
|
6
|
Pizzolato-Cezar LR, Spira B, Machini MT. Bacterial toxin-antitoxin systems: Novel insights on toxin activation across populations and experimental shortcomings. CURRENT RESEARCH IN MICROBIAL SCIENCES 2023; 5:100204. [PMID: 38024808 PMCID: PMC10643148 DOI: 10.1016/j.crmicr.2023.100204] [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: 12/01/2023] Open
Abstract
The alarming rise in hard-to-treat bacterial infections is of great concern to human health. Thus, the identification of molecular mechanisms that enable the survival and growth of pathogens is of utmost urgency for the development of more efficient antimicrobial therapies. In challenging environments, such as presence of antibiotics, or during host infection, metabolic adjustments are essential for microorganism survival and competitiveness. Toxin-antitoxin systems (TASs) consisting of a toxin with metabolic modulating activity and a cognate antitoxin that antagonizes that toxin are important elements in the arsenal of bacterial stress defense. However, the exact physiological function of TA systems is highly debatable and with the exception of stabilization of mobile genetic elements and phage inhibition, other proposed biological functions lack a broad consensus. This review aims at gaining new insights into the physiological effects of TASs in bacteria and exploring the experimental shortcomings that lead to discrepant results in TAS research. Distinct control mechanisms ensure that only subsets of cells within isogenic cultures transiently develop moderate levels of toxin activity. As a result, TASs cause phenotypic growth heterogeneity rather than cell stasis in the entire population. It is this feature that allows bacteria to thrive in diverse environments through the creation of subpopulations with different metabolic rates and stress tolerance programs.
Collapse
Affiliation(s)
- Luis R. Pizzolato-Cezar
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Beny Spira
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - M. Teresa Machini
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| |
Collapse
|
7
|
Kohm K, Jalomo-Khayrova E, Krüger A, Basu S, Steinchen W, Bange G, Frunzke J, Hertel R, Commichau F, Czech L. Structural and functional characterization of MrpR, the master repressor of the Bacillus subtilis prophage SPβ. Nucleic Acids Res 2023; 51:9452-9474. [PMID: 37602373 PMCID: PMC10516654 DOI: 10.1093/nar/gkad675] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 07/11/2023] [Accepted: 08/09/2023] [Indexed: 08/22/2023] Open
Abstract
Prophages control their lifestyle to either be maintained within the host genome or enter the lytic cycle. Bacillus subtilis contains the SPβ prophage whose lysogenic state depends on the MrpR (YopR) protein, a key component of the lysis-lysogeny decision system. Using a historic B. subtilis strain harboring the heat-sensitive SPβ c2 mutant, we demonstrate that the lytic cycle of SPβ c2 can be induced by heat due to a single nucleotide exchange in the mrpR gene, rendering the encoded MrpRG136E protein temperature-sensitive. Structural characterization revealed that MrpR is a DNA-binding protein resembling the overall fold of tyrosine recombinases. MrpR has lost its recombinase function and the G136E exchange impairs its higher-order structure and DNA binding activity. Genome-wide profiling of MrpR binding revealed its association with the previously identified SPbeta repeated element (SPBRE) in the SPβ genome. MrpR functions as a master repressor of SPβ that binds to this conserved element to maintain lysogeny. The heat-inducible excision of the SPβ c2 mutant remains reliant on the serine recombinase SprA. A suppressor mutant analysis identified a previously unknown component of the lysis-lysogeny management system that is crucial for the induction of the lytic cycle of SPβ.
Collapse
Affiliation(s)
- Katharina Kohm
- FG Synthetic Microbiology, Institute for Biotechnology, BTU Cottbus-Senftenberg, Senftenberg, Germany
- FG Molecular Microbiology, Institute for Biology, University of Hohenheim, Stuttgart, Germany
| | - Ekaterina Jalomo-Khayrova
- Center for Synthetic Microbiology (SYNMIKRO) and Department of Chemistry, Phillips-University Marburg, Marburg, Germany
| | - Aileen Krüger
- Institute of Bio- and Geosciences, iBG-1: Biotechnology, FZ Jülich, Germany
| | - Syamantak Basu
- FG Synthetic Microbiology, Institute for Biotechnology, BTU Cottbus-Senftenberg, Senftenberg, Germany
| | - Wieland Steinchen
- Center for Synthetic Microbiology (SYNMIKRO) and Department of Chemistry, Phillips-University Marburg, Marburg, Germany
| | - Gert Bange
- Center for Synthetic Microbiology (SYNMIKRO) and Department of Chemistry, Phillips-University Marburg, Marburg, Germany
- Max-Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Julia Frunzke
- Institute of Bio- and Geosciences, iBG-1: Biotechnology, FZ Jülich, Germany
| | - Robert Hertel
- FG Synthetic Microbiology, Institute for Biotechnology, BTU Cottbus-Senftenberg, Senftenberg, Germany
- Department of Genomic and Applied Microbiology, Institute of Microbiology and Genetics, Georg-August-University of Göttingen, Göttingen, Germany
| | - Fabian M Commichau
- FG Synthetic Microbiology, Institute for Biotechnology, BTU Cottbus-Senftenberg, Senftenberg, Germany
- FG Molecular Microbiology, Institute for Biology, University of Hohenheim, Stuttgart, Germany
| | - Laura Czech
- Center for Synthetic Microbiology (SYNMIKRO) and Department of Chemistry, Phillips-University Marburg, Marburg, Germany
| |
Collapse
|
8
|
Boss L, Kędzierska B. Bacterial Toxin-Antitoxin Systems' Cross-Interactions-Implications for Practical Use in Medicine and Biotechnology. Toxins (Basel) 2023; 15:380. [PMID: 37368681 DOI: 10.3390/toxins15060380] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 05/30/2023] [Accepted: 06/02/2023] [Indexed: 06/29/2023] Open
Abstract
Toxin-antitoxin (TA) systems are widely present in bacterial genomes. They consist of stable toxins and unstable antitoxins that are classified into distinct groups based on their structure and biological activity. TA systems are mostly related to mobile genetic elements and can be easily acquired through horizontal gene transfer. The ubiquity of different homologous and non-homologous TA systems within a single bacterial genome raises questions about their potential cross-interactions. Unspecific cross-talk between toxins and antitoxins of non-cognate modules may unbalance the ratio of the interacting partners and cause an increase in the free toxin level, which can be deleterious to the cell. Moreover, TA systems can be involved in broadly understood molecular networks as transcriptional regulators of other genes' expression or modulators of cellular mRNA stability. In nature, multiple copies of highly similar or identical TA systems are rather infrequent and probably represent a transition stage during evolution to complete insulation or decay of one of them. Nevertheless, several types of cross-interactions have been described in the literature to date. This implies a question of the possibility and consequences of the TA system cross-interactions, especially in the context of the practical application of the TA-based biotechnological and medical strategies, in which such TAs will be used outside their natural context, will be artificially introduced and induced in the new hosts. Thus, in this review, we discuss the prospective challenges of system cross-talks in the safety and effectiveness of TA system usage.
Collapse
Affiliation(s)
- Lidia Boss
- Department of Bacterial Molecular Genetics, Faculty of Biology, University of Gdańsk, 80-309 Gdańsk, Poland
| | - Barbara Kędzierska
- Department of Bacterial Molecular Genetics, Faculty of Biology, University of Gdańsk, 80-309 Gdańsk, Poland
| |
Collapse
|