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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: 24] [Impact Index Per Article: 24.0] [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.
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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.
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2
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Cooke MB, Herman C. Conjugation's Toolkit: the Roles of Nonstructural Proteins in Bacterial Sex. J Bacteriol 2023; 205:e0043822. [PMID: 36847532 PMCID: PMC10029717 DOI: 10.1128/jb.00438-22] [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] [Indexed: 03/01/2023] Open
Abstract
Bacterial conjugation, a form of horizontal gene transfer, relies on a type 4 secretion system (T4SS) and a set of nonstructural genes that are closely linked. These nonstructural genes aid in the mobile lifestyle of conjugative elements but are not part of the T4SS apparatus for conjugative transfer, such as the membrane pore and relaxosome, or the plasmid maintenance and replication machineries. While these nonstructural genes are not essential for conjugation, they assist in core conjugative functions and mitigate the cellular burden on the host. This review compiles and categorizes known functions of nonstructural genes by the stage of conjugation they modulate: dormancy, transfer, and new host establishment. Themes include establishing a commensalistic relationship with the host, manipulating the host for efficient T4SS assembly and function and assisting in conjugative evasion of recipient cell immune functions. These genes, taken in a broad ecological context, play important roles in ensuring proper propagation of the conjugation system in a natural environment.
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Affiliation(s)
- Matthew B. Cooke
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - Christophe Herman
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA
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3
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Pilosof S. Conceptualizing microbe-plasmid communities as complex adaptive systems. Trends Microbiol 2023:S0966-842X(23)00025-2. [PMID: 36822952 DOI: 10.1016/j.tim.2023.01.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 12/29/2022] [Accepted: 01/23/2023] [Indexed: 02/24/2023]
Abstract
Plasmids shape microbial communities' diversity, structure, and function. Nevertheless, we lack a mechanistic understanding of how community structure and dynamics emerge from local microbe-plasmid interactions and coevolution. Addressing this gap is challenging because multiple processes operate simultaneously at multiple levels of organization. For example, immunity operates between a plasmid and a cell, but incompatibility mechanisms regulate coexistence between plasmids. Conceptualizing microbe-plasmid communities as complex adaptive systems is a promising approach to overcoming these challenges. I illustrate how agent-based evolutionary modeling, extended by network analysis, can be used to quantify the relative importance of local processes governing community dynamics. These theoretical developments can advance our understanding of plasmid ecology and evolution, especially when combined with empirical data.
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Affiliation(s)
- Shai Pilosof
- Department of Life Sciences, Ben-Gurion University of the Negev, Be'er-Sheva, Israel.
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4
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Robledo M, Álvarez B, Cuevas A, González S, Ruano-Gallego D, Fernández L, de la Cruz F. Targeted bacterial conjugation mediated by synthetic cell-to-cell adhesions. Nucleic Acids Res 2022; 50:12938-12950. [PMID: 36511856 PMCID: PMC9825185 DOI: 10.1093/nar/gkac1164] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 11/18/2022] [Accepted: 11/23/2022] [Indexed: 12/15/2022] Open
Abstract
Genetic interventions on microbiomes, for clinical or biotechnological purposes, remain challenging. Conjugation-based delivery of genetic cargo is still unspecific and limited by low conjugation rates. Here we report an approach to overcome these problems, based on a synthetic bacterial adhesion system. Mating assemblers consist on a synthetic adhesion formed by the expression on the surface of donor and target cells of specific nanobodies (Nb) and their cognate antigen (Ag). The Nb-Ag bridge increased 1-3 logs transfer of a variety of plasmids, especially in liquid media, confirming that cell-cell docking is a main determinant limiting mating efficiency. Synthetic cell-to-cell adhesion allows efficient conjugation to targeted recipients, enhancing delivery of desired genes to a predefined subset of prey species, or even specific pathogenic strains such as enterohemorrhagic Escherichia coli (EHEC), within a bacterial community. The synthetic conjugation enhancer presented here optimizes plasmid delivery by selecting the target hosts with high selectivity.
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Affiliation(s)
- Marta Robledo
- Correspondence may also be addressed to Marta Robledo.
| | - Beatriz Álvarez
- Department of Microbial Biotechnology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Campus UAM Cantoblanco, 28049 Madrid, Spain
| | - Ana Cuevas
- Intergenomics Group, Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), CSIC-Universidad de Cantabria, 39011, Santander, Spain
| | - Sheila González
- Intergenomics Group, Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC), CSIC-Universidad de Cantabria, 39011, Santander, Spain
| | - David Ruano-Gallego
- Department of Microbial Biotechnology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Campus UAM Cantoblanco, 28049 Madrid, Spain
| | - Luis Ángel Fernández
- Department of Microbial Biotechnology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Campus UAM Cantoblanco, 28049 Madrid, Spain
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5
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Igler C, Huisman JS, Siedentop B, Bonhoeffer S, Lehtinen S. Plasmid co-infection: linking biological mechanisms to ecological and evolutionary dynamics. Philos Trans R Soc Lond B Biol Sci 2022; 377:20200478. [PMID: 34839701 PMCID: PMC8628072 DOI: 10.1098/rstb.2020.0478] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 07/09/2021] [Indexed: 12/27/2022] Open
Abstract
As infectious agents of bacteria and vehicles of horizontal gene transfer, plasmids play a key role in bacterial ecology and evolution. Plasmid dynamics are shaped not only by plasmid-host interactions but also by ecological interactions between plasmid variants. These interactions are complex: plasmids can co-infect the same cell and the consequences for the co-resident plasmid can be either beneficial or detrimental. Many of the biological processes that govern plasmid co-infection-from systems that exclude infection by other plasmids to interactions in the regulation of plasmid copy number-are well characterized at a mechanistic level. Modelling plays a central role in translating such mechanistic insights into predictions about plasmid dynamics and the impact of these dynamics on bacterial evolution. Theoretical work in evolutionary epidemiology has shown that formulating models of co-infection is not trivial, as some modelling choices can introduce unintended ecological assumptions. Here, we review how the biological processes that govern co-infection can be represented in a mathematical model, discuss potential modelling pitfalls, and analyse this model to provide general insights into how co-infection impacts ecological and evolutionary outcomes. In particular, we demonstrate how beneficial and detrimental effects of co-infection give rise to frequency-dependent selection on plasmid variants. This article is part of the theme issue 'The secret lives of microbial mobile genetic elements'.
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Affiliation(s)
- Claudia Igler
- Institute of Integrative Biology, Department of Environmental Systems Science, ETH Zürich, Zurich, Switzerland
| | - Jana S. Huisman
- Institute of Integrative Biology, Department of Environmental Systems Science, ETH Zürich, Zurich, Switzerland
- Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - Berit Siedentop
- Institute of Integrative Biology, Department of Environmental Systems Science, ETH Zürich, Zurich, Switzerland
| | - Sebastian Bonhoeffer
- Institute of Integrative Biology, Department of Environmental Systems Science, ETH Zürich, Zurich, Switzerland
| | - Sonja Lehtinen
- Institute of Integrative Biology, Department of Environmental Systems Science, ETH Zürich, Zurich, Switzerland
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Shen Z, Tang CM, Liu GY. Towards a better understanding of antimicrobial resistance dissemination: what can be learnt from studying model conjugative plasmids? Mil Med Res 2022; 9:3. [PMID: 35012680 PMCID: PMC8744291 DOI: 10.1186/s40779-021-00362-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 12/26/2021] [Indexed: 12/12/2022] Open
Abstract
Bacteria can evolve rapidly by acquiring new traits such as virulence, metabolic properties, and most importantly, antimicrobial resistance, through horizontal gene transfer (HGT). Multidrug resistance in bacteria, especially in Gram-negative organisms, has become a global public health threat often through the spread of mobile genetic elements. Conjugation represents a major form of HGT and involves the transfer of DNA from a donor bacterium to a recipient by direct contact. Conjugative plasmids, a major vehicle for the dissemination of antimicrobial resistance, are selfish elements capable of mediating their own transmission through conjugation. To spread to and survive in a new bacterial host, conjugative plasmids have evolved mechanisms to circumvent both host defense systems and compete with co-resident plasmids. Such mechanisms have mostly been studied in model plasmids such as the F plasmid, rather than in conjugative plasmids that confer antimicrobial resistance (AMR) in important human pathogens. A better understanding of these mechanisms is crucial for predicting the flow of antimicrobial resistance-conferring conjugative plasmids among bacterial populations and guiding the rational design of strategies to halt the spread of antimicrobial resistance. Here, we review mechanisms employed by conjugative plasmids that promote their transmission and establishment in Gram-negative bacteria, by following the life cycle of conjugative plasmids.
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Affiliation(s)
- Zhen Shen
- Sir William Dunn School of Pathology, University of Oxford, Oxford, OX1 3RE, UK.,Department of Laboratory Medicine, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200127, China
| | - Christoph M Tang
- Sir William Dunn School of Pathology, University of Oxford, Oxford, OX1 3RE, UK
| | - Guang-Yu Liu
- Sir William Dunn School of Pathology, University of Oxford, Oxford, OX1 3RE, UK.
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7
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Gama JA, Fredheim EGA, Cléon F, Reis AM, Zilhão R, Dionisio F. Dominance Between Plasmids Determines the Extent of Biofilm Formation. Front Microbiol 2020; 11:2070. [PMID: 32983050 PMCID: PMC7479130 DOI: 10.3389/fmicb.2020.02070] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 08/06/2020] [Indexed: 01/18/2023] Open
Abstract
Bacterial biofilms have an impact in medical and industrial environments because they often confer protection to bacteria against harmful agents, and constitute a source from which microorganisms can disperse. Conjugative plasmids can enhance bacterial ability to form biofilms because conjugative pili act as adhesion factors. However, plasmids may interact with each other, either facilitating or inhibiting plasmid transfer. Accordingly, we asked whether effects on plasmid transfer also impacts biofilm formation. We measured biofilm formation of Escherichia coli cells harboring two plasmid types, or when the two plasmids were present in the same population but carried in different cells. Using eleven natural isolated conjugative plasmids, we confirmed that some indeed promote biofilm formation and, importantly, that this ability is correlated with conjugative efficiency. Further we studied the effect of plasmid pairs on biofilm formation. We observed increased biofilm formation in approximately half of the combinations when both plasmids inhabited the same cell or when the plasmids were carried in different cells. Moreover, in approximately half of the combinations, independent of the co-inhabitation conditions, one of the plasmids alone determined the extent of biofilm formation – thus having a dominant effect over the other plasmid. The molecular mechanisms responsible for these interactions were not evaluated here and future research is required to elucidate them.
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Affiliation(s)
- João Alves Gama
- Department of Pharmacy, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway
| | | | - François Cléon
- Department of Pharmacy, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway
| | - Ana Maria Reis
- Biosystems and Integrative Sciences Institute (BioISI), Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal.,Departamento de Biologia Vegetal, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Rita Zilhão
- Departamento de Biologia Vegetal, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Francisco Dionisio
- Departamento de Biologia Vegetal, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal.,Centre for Ecology, Evolution and Environmental Changes (cE3c), Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
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8
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Garcillán-Barcia MP, Cuartas-Lanza R, Cuevas A, de la Cruz F. Cis-Acting Relaxases Guarantee Independent Mobilization of MOB Q 4 Plasmids. Front Microbiol 2019; 10:2557. [PMID: 31781067 PMCID: PMC6856555 DOI: 10.3389/fmicb.2019.02557] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 10/23/2019] [Indexed: 12/16/2022] Open
Abstract
Plasmids are key vehicles of horizontal gene transfer and contribute greatly to bacterial genome plasticity. In this work, we studied a group of plasmids from enterobacteria that encode phylogenetically related mobilization functions that populate the previously non-described MOBQ4 relaxase family. These plasmids encode two transfer genes: mobA coding for the MOBQ4 relaxase; and mobC, which is non-essential but enhances the plasmid mobilization frequency. The origin of transfer is located between these two divergently transcribed mob genes. We found that MPFI conjugative plasmids were the most efficient helpers for MOBQ4 conjugative dissemination among clinically relevant enterobacteria. While highly similar in their mobilization module, two sub-groups with unrelated replicons (Rep_3 and ColE2) can be distinguished in this plasmid family. These subgroups can stably coexist (are compatible) and transfer independently, despite origin-of-transfer cross-recognition by their relaxases. Specific discrimination among their highly similar oriT sequences is guaranteed by the preferential cis activity of the MOBQ4 relaxases. Such a strategy would be biologically relevant in a scenario of co-residence of non-divergent elements to favor self-dissemination.
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Affiliation(s)
- M Pilar Garcillán-Barcia
- Instituto de Biomedicina y Biotecnología de Cantabria (Universidad de Cantabria - Consejo Superior de Investigaciones Científicas), Santander, Spain
| | - Raquel Cuartas-Lanza
- Instituto de Biomedicina y Biotecnología de Cantabria (Universidad de Cantabria - Consejo Superior de Investigaciones Científicas), Santander, Spain
| | - Ana Cuevas
- Instituto de Biomedicina y Biotecnología de Cantabria (Universidad de Cantabria - Consejo Superior de Investigaciones Científicas), Santander, Spain
| | - Fernando de la Cruz
- Instituto de Biomedicina y Biotecnología de Cantabria (Universidad de Cantabria - Consejo Superior de Investigaciones Científicas), Santander, Spain
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9
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Tymensen L, Booker CW, Hannon SJ, Cook SR, Jokinen CC, Zaheer R, Read R, Boerlin P, McAllister TA. Plasmid Distribution among Escherichia coli from Livestock and Associated Wastewater: Unraveling Factors That Shape the Presence of Genes Conferring Third-Generation Cephalosporin Resistance. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:11666-11674. [PMID: 31532641 DOI: 10.1021/acs.est.9b03486] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
A key concern with agricultural wastewater storage ponds is that they may provide an environment conducive for horizontal exchange of antibiotic resistance genes (ARGs), thereby facilitating the emergence of antibiotic resistant pathogens. Central to this exchange are mobile genetic elements like plasmids; yet, the factors shaping their presence in agricultural environments remain poorly understood. Here, using Escherichia coli as a model bacterium, we examined genetic backgrounds and plasmid profiles of generic fecal and wastewater isolates and those possessing blaCTX-M and blaCMY-2 genes (which confer resistance to third-generation cephalosporins) to delineate factors shaping the environmental persistence of plasmid-associated ARGs in beef cattle feedlots. The wastewater environment exerted minimal influence on plasmid repertoires, as the number of plasmids and distribution of different incompatibility groups did not differ between generic fecal and wastewater isolates. The blaCTX-M and blaCMY-2 genes were associated with IncF and IncA/C plasmids, respectively, and host isolates possessing these ARGs had fewer plasmids than generic isolates, suggesting ARG-bearing plasmids may associate predominantly with such hosts to compensate for the metabolic burden imposed by these plasmids. Phylogeny also appeared to be a factor for blaCTX-M genes, as their bacterial hosts were restricted to particular genetic lineages, including the environmentally adapted ET-1 clade, as noted previously for these genes. Ultimately, these findings have important implications for evaluating human health risks of agricultural wastewater with respect to environmental persistence of ARGs and may help identify options for improving wastewater treatment.
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Affiliation(s)
- Lisa Tymensen
- Irrigation and Farm Water Branch, Alberta Agriculture and Forestry , Lethbridge , Alberta Canada , T1J 4V6
| | - Calvin W Booker
- Feedlot Health Management Services, Ltd. , Okotoks , Alberta Canada , T1S 2A2
| | - Sherry J Hannon
- Feedlot Health Management Services, Ltd. , Okotoks , Alberta Canada , T1S 2A2
| | - Shaun R Cook
- Irrigation and Farm Water Branch, Alberta Agriculture and Forestry , Lethbridge , Alberta Canada , T1J 4V6
- Agriculture and Agri-Food Canada , Lethbridge , Alberta Canada , T1J 4B1
| | - Cassandra C Jokinen
- Irrigation and Farm Water Branch, Alberta Agriculture and Forestry , Lethbridge , Alberta Canada , T1J 4V6
| | - Rahat Zaheer
- Agriculture and Agri-Food Canada , Lethbridge , Alberta Canada , T1J 4B1
| | - Ron Read
- Microbiology, Immunology and Infectious Diseases , University of Calgary , Calgary , Alberta Canada , T1Y 6J4
| | - Patrick Boerlin
- Department of Pathobiology , University of Guelph , 50 Stone Road East , Guelph , Ontario Canada , N1G 2W1
| | - Tim A McAllister
- Agriculture and Agri-Food Canada , Lethbridge , Alberta Canada , T1J 4B1
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10
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Mutai WC, Waiyaki PG, Kariuki S, Muigai AWT. Plasmid profiling and incompatibility grouping of multidrug resistant Salmonella enterica serovar Typhi isolates in Nairobi, Kenya. BMC Res Notes 2019; 12:422. [PMID: 31311578 PMCID: PMC6636098 DOI: 10.1186/s13104-019-4468-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 07/11/2019] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVES Plasmids harbour antibiotic resistance genes which contribute to the emergence of multidrug resistant pathogens. We detected the presence of plasmids in multidrug resistant Salmonella enterica serovar Typhi (S. Typhi) isolates from our previous study and consequently determined their incompatibility groups and possibility of conjugation transmission. Plasmids were extracted from 98 multidrug resistant S. Typhi isolates based on alkaline lysis technique. Plasmid incompatibility grouping was established by PCR replicon typing using 18 pairs of primers to amplify FIA, FIB, FIC, HI1, HI2, I1-Iγ, L/M, N, P, W, T, A/C, K, B/O, X, Y, F and FIIA replicons. Antibiotic resistance phenotypes were conjugally transferred from S. Typhi isolates with plasmids to Escherichia coli K12F strain devoid of plasmids. RESULTS Approximately 79.6% of the MDR S. Typhi isolates were related to the existence of plasmids. We detected 93.6% of plasmids belonging to incompatibility (Inc) group HI1. The other incompatibility groups identified included IncFIC (16.7%), IncP (1.3%), and IncI1 (1.3%) which appeared together with Inc HI1. MDR S. Typhi isolated carried a homologous plasmid of incompatibility group HI1 most of which transferred the resistance phenotypes of ampicillin, tetracycline and chloramphenicol to the transconjugants.
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Affiliation(s)
- Winnie C Mutai
- Department of Medical Microbiology, School of Medicine, University of Nairobi, Nairobi, Kenya.
| | - Peter G Waiyaki
- Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - Samuel Kariuki
- Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - Anne W T Muigai
- School of Biological Sciences, Jomo Kenyatta University of Agriculture and Technology, Juja, Kenya
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Dionisio F, Zilhão R, Gama JA. Interactions between plasmids and other mobile genetic elements affect their transmission and persistence. Plasmid 2019; 102:29-36. [DOI: 10.1016/j.plasmid.2019.01.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 01/24/2019] [Accepted: 01/30/2019] [Indexed: 10/27/2022]
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12
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Goñi-Moreno A, de la Cruz F, Rodríguez-Patón A, Amos M. Dynamical Task Switching in Cellular Computers. Life (Basel) 2019; 9:E14. [PMID: 30691149 PMCID: PMC6463194 DOI: 10.3390/life9010014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 12/23/2018] [Accepted: 01/23/2019] [Indexed: 01/24/2023] Open
Abstract
We present a scheme for implementing a version of task switching in engineered bacteria, based on the manipulation of plasmid copy numbers. Our method allows for the embedding of multiple computations in a cellular population, whilst minimising resource usage inefficiency. We describe the results of computational simulations of our model, and discuss the potential for future work in this area.
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Affiliation(s)
- Angel Goñi-Moreno
- School of Computing, Newcastle University, Newcastle Upon Tyne NE4 5TG, UK.
| | - Fernando de la Cruz
- Instituto de Biomedicina y Biotecnología de Cantabria, Universidad de Cantabria, 39011 Santander, Spain.
| | - Alfonso Rodríguez-Patón
- Departamento de Inteligencia Artificial, Universidad Politécnica de Madrid, 28660 Madrid, Spain.
| | - Martyn Amos
- Department of Computer and Information Sciences, Northumbria University, Newcastle upon Tyne NE1 8ST, UK.
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