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Mancuso CP, Baker JS, Qu E, Tripp AD, Balogun IO, Lieberman TD. Intraspecies warfare restricts strain coexistence in human skin microbiomes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.07.592803. [PMID: 38765968 PMCID: PMC11100718 DOI: 10.1101/2024.05.07.592803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Determining why only a fraction of encountered or applied bacterial strains engraft in a given person's microbiome is crucial for understanding and engineering these communities1. Previous work has established that metabolism can determine colonization success in vivo2-4, but relevance of bacterial warfare in preventing engraftment has been less explored. Here, we demonstrate that intraspecies warfare presents a significant barrier to strain transmission in the skin microbiome by profiling 14,884 pairwise interactions between Staphylococcus epidermidis cultured from eighteen human subjects from six families. We find that intraspecies antagonisms are abundant; these interactions are mechanistically diverse, independent of the relatedness between strains, and consistent with rapid evolution via horizontal gene transfer. Ability to antagonize more strains is associated with reaching a higher fraction of the on-person S. epidermidis community. Moreover, antagonisms are significantly depleted among strains residing on the same person relative to random assemblages. Two notable exceptions, in which bacteria evolved to become sensitive to antimicrobials found on the same host, are explained by mutations that provide phage resistance, contextualizing the importance of warfare among other lethal selective pressures. Taken together, our results emphasize that accounting for intraspecies bacterial warfare is essential to the design of long-lasting probiotic therapeutics.
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Affiliation(s)
- Christopher P. Mancuso
- Institute for Medical Engineering and Sciences, Massachusetts Institute of Technology; Cambridge, MA 02142, USA
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology; Cambridge, MA 02142, USA
| | - Jacob S. Baker
- Institute for Medical Engineering and Sciences, Massachusetts Institute of Technology; Cambridge, MA 02142, USA
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology; Cambridge, MA 02142, USA
| | - Evan Qu
- Institute for Medical Engineering and Sciences, Massachusetts Institute of Technology; Cambridge, MA 02142, USA
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology; Cambridge, MA 02142, USA
| | - A. Delphine Tripp
- Institute for Medical Engineering and Sciences, Massachusetts Institute of Technology; Cambridge, MA 02142, USA
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology; Cambridge, MA 02142, USA
- Department of Systems Biology, Harvard University; Cambridge, MA 02138, USA
| | - Ishaq O. Balogun
- Institute for Medical Engineering and Sciences, Massachusetts Institute of Technology; Cambridge, MA 02142, USA
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology; Cambridge, MA 02142, USA
| | - Tami D. Lieberman
- Institute for Medical Engineering and Sciences, Massachusetts Institute of Technology; Cambridge, MA 02142, USA
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology; Cambridge, MA 02142, USA
- Broad Institute of MIT and Harvard; Cambridge, MA 02142, USA
- Ragon Institute of MGH, MIT, and Harvard; Cambridge, MA 02142, USA
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2
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Reuben RC, Torres C. Bacteriocins: potentials and prospects in health and agrifood systems. Arch Microbiol 2024; 206:233. [PMID: 38662051 PMCID: PMC11045635 DOI: 10.1007/s00203-024-03948-y] [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: 02/02/2024] [Revised: 03/27/2024] [Accepted: 03/28/2024] [Indexed: 04/26/2024]
Abstract
Bacteriocins are highly diverse, abundant, and heterogeneous antimicrobial peptides that are ribosomally synthesized by bacteria and archaea. Since their discovery about a century ago, there has been a growing interest in bacteriocin research and applications. This is mainly due to their high antimicrobial properties, narrow or broad spectrum of activity, specificity, low cytotoxicity, and stability. Though initially used to improve food quality and safety, bacteriocins are now globally exploited for innovative applications in human, animal, and food systems as sustainable alternatives to antibiotics. Bacteriocins have the potential to beneficially modulate microbiota, providing viable microbiome-based solutions for the treatment, management, and non-invasive bio-diagnosis of infectious and non-infectious diseases. The use of bacteriocins holds great promise in the modulation of food microbiomes, antimicrobial food packaging, bio-sanitizers and antibiofilm, pre/post-harvest biocontrol, functional food, growth promotion, and sustainable aquaculture. This can undoubtedly improve food security, safety, and quality globally. This review highlights the current trends in bacteriocin research, especially the increasing research outputs and funding, which we believe may proportionate the soaring global interest in bacteriocins. The use of cutting-edge technologies, such as bioengineering, can further enhance the exploitation of bacteriocins for innovative applications in human, animal, and food systems.
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Affiliation(s)
- Rine Christopher Reuben
- Area of Biochemistry and Molecular Biology, OneHealth-UR Research Group, University of La Rioja, 26006, Logroño, Spain.
| | - Carmen Torres
- Area of Biochemistry and Molecular Biology, OneHealth-UR Research Group, University of La Rioja, 26006, Logroño, Spain
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3
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Goldman AL, Fulk EM, Momper LM, Heider C, Mulligan J, Osburn M, Masiello CA, Silberg JJ. Microbial sensor variation across biogeochemical conditions in the terrestrial deep subsurface. mSystems 2024; 9:e0096623. [PMID: 38059636 PMCID: PMC10805038 DOI: 10.1128/msystems.00966-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 11/08/2023] [Indexed: 12/08/2023] Open
Abstract
Microbes can be found in abundance many kilometers underground. While microbial metabolic capabilities have been examined across different geochemical settings, it remains unclear how changes in subsurface niches affect microbial needs to sense and respond to their environment. To address this question, we examined how microbial extracellular sensor systems vary with environmental conditions across metagenomes at different Deep Mine Microbial Observatory (DeMMO) subsurface sites. Because two-component systems (TCSs) directly sense extracellular conditions and convert this information into intracellular biochemical responses, we expected that this sensor family would vary across isolated oligotrophic subterranean environments that differ in abiotic and biotic conditions. TCSs were found at all six subsurface sites, the service water control, and the surface site, with an average of 0.88 sensor histidine kinases (HKs) per 100 genes across all sites. Abundance was greater in subsurface fracture fluids compared with surface-derived fluids, and candidate phyla radiation (CPR) bacteria presented the lowest HK frequencies. Measures of microbial diversity, such as the Shannon diversity index, revealed that HK abundance is inversely correlated with microbial diversity (r2 = 0.81). Among the geochemical parameters measured, HK frequency correlated most strongly with variance in dissolved organic carbon (r2 = 0.82). Taken together, these results implicate the abiotic and biotic properties of an ecological niche as drivers of sensor needs, and they suggest that microbes in environments with large fluctuations in organic nutrients (e.g., lacustrine, terrestrial, and coastal ecosystems) may require greater TCS diversity than ecosystems with low nutrients (e.g., open ocean).IMPORTANCEThe ability to detect extracellular environmental conditions is a fundamental property of all life forms. Because microbial two-component sensor systems convert information about extracellular conditions into biochemical information that controls their behaviors, we evaluated how two-component sensor systems evolved within the deep Earth across multiple sites where abiotic and biotic properties vary. We show that these sensor systems remain abundant in microbial consortia at all subterranean sampling sites and observe correlations between sensor system abundances and abiotic (dissolved organic carbon variation) and biotic (consortia diversity) properties. These results suggest that multiple environmental properties may drive sensor protein evolution and highlight the need for further studies of metagenomic and geochemical data in parallel to understand the drivers of microbial sensor evolution.
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Affiliation(s)
| | - Emily M. Fulk
- Systems, Synthetic, and Physical Biology Graduate Program, Rice University, Houston, Texas, USA
| | - Lily M. Momper
- Department of Earth and Planetary Sciences, Northwestern University, Evanston, Illinois, USA
| | - Clinton Heider
- Rice University, Center for Research Computing, Houston, Texas, USA
| | - John Mulligan
- Rice University, Center for Research Computing, Houston, Texas, USA
| | - Magdalena Osburn
- Department of Earth and Planetary Sciences, Northwestern University, Evanston, Illinois, USA
| | - Caroline A. Masiello
- Department of Biosciences, Rice University, Houston, Texas, USA
- Department of Earth, Environmental and Planetary Sciences, Rice University, Houston, Texas, USA
- Department of Chemistry, Rice University, Houston, Texas, USA
| | - Jonathan J. Silberg
- Department of Biosciences, Rice University, Houston, Texas, USA
- Department of Bioengineering, Rice University, Houston, Texas, USA
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas, USA
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Verdú M, Alcántara JM, Navarro-Cano JA, Goberna M. Transitivity and intransitivity in soil bacterial networks. THE ISME JOURNAL 2023; 17:2135-2139. [PMID: 37857708 PMCID: PMC10689798 DOI: 10.1038/s41396-023-01540-8] [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: 01/16/2023] [Revised: 10/09/2023] [Accepted: 10/10/2023] [Indexed: 10/21/2023]
Abstract
Competition can lead to the exclusion of bacterial taxa when there is a transitive relationship among competitors with a hierarchy of competitive success. However, competition may not prevent bacterial coexistence if competitors form intransitive loops, in which none is able to outcompete all the rest. Both transitive and intransitive competition have been demonstrated in bacterial model systems. However, in natural soil microbial assemblages competition is typically understood as a dominance relationship leading to the exclusion of weak competitors. Here, we argue that transitive and intransitive interactions concurrently determine the structure of soil microbial communities. We explain why pairwise interactions cannot depict competition correctly in complex communities, and propose an alternative through the detection of strongly connected components (SCCs) in microbial networks. We finally analyse the existence of SCCs in soil bacterial communities in two Mediterranean ecosystems, for illustrative purposes only (rather than with the aim of providing a methodological tool) due to current limitations, and discuss future avenues to experimentally test the existence of SCCs in nature.
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Affiliation(s)
- Miguel Verdú
- Centro de Investigaciones Sobre Desertificación (CIDE), CSIC-UV-GV, Moncada, Spain
| | - Julio M Alcántara
- Departamento de Biología Animal, Biología Vegetal y Ecología, Universidad de Jaén, Jaén, Spain
- Instituto Interuniversitario de Investigación del Sistema Tierra en Andalucía, Granada, Spain
| | - Jose A Navarro-Cano
- Departamento de Medio Ambiente y Agronomía, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), CSIC, Madrid, Spain
| | - Marta Goberna
- Departamento de Medio Ambiente y Agronomía, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), CSIC, Madrid, Spain.
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De Silva PM, Bennett RJ, Kuhn L, Ngondo P, Debande L, Njamkepo E, Ho B, Weill FX, Marteyn BS, Jenkins C, Baker KS. Escherichia coli killing by epidemiologically successful sublineages of Shigella sonnei is mediated by colicins. EBioMedicine 2023; 97:104822. [PMID: 37806286 PMCID: PMC10579285 DOI: 10.1016/j.ebiom.2023.104822] [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: 04/11/2023] [Revised: 09/20/2023] [Accepted: 09/21/2023] [Indexed: 10/10/2023] Open
Abstract
BACKGROUND Shigella sp. are enteric pathogens which causes >125 million cases of shigellosis annually. S. sonnei accounts for about a quarter of those cases and is increasingly prevalent in industrialising nations. Being an enteric pathogen, S. sonnei benefits from outcompeting gut commensals such as Escherichia coli to establish itself and cause disease. There are numerous mechanisms that bacterial pathogens use to outcompete its rivals including molecules called colicins. A Type 6 Secretion System (T6SS) was recently described as contributing to E. coli killing in S. sonnei. METHODS We used Bulk Phenotyping of Epidemiological Replicates (BPER) which combined bacterial Genome Wide Association Studies (bGWAS) and high throughput phenotyping on a collection of S. sonnei surveillance isolates to identify the genetic features associated with E. coli killing and explore their relationship with epidemiological behaviour. We further explored the presence of colicins and T6SS components in the isolates using genomics, laboratory experimentation, and proteomics. FINDINGS Our bGWAS analysis returned known and novel colicin and colicin related genes as significantly associated with E. coli killing. In silico analyses identified key colicin clusters responsible for the killing phenotype associated with epidemiologically successful sub-lineages. The killing phenotype was not associated with the presence of a T6SS. Laboratory analyses confirmed the presence of the key colicin clusters and that killing was contact-independent. INTERPRETATION Colicins are responsible for E. coli killing by S. sonnei, not a T6SS. This phenotype contributes to shaping the observed epidemiology of S. sonnei and may contribute to its increasing prevalence globally. BPER is an epidemiologically relevant approach to phenotypic testing that enables the rapid identification of genetic drivers of phenotypic changes, and assessment of their relevance to epidemiology in natural settings. FUNDING Biotechnology and Biological Sciences Research Council, Biotechnology and Biological Sciences Research Council Doctoral Training Partnership studentship, Wellcome Trust, Medical Research Council (UK), French National Research Agency.
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Affiliation(s)
- P Malaka De Silva
- Department of Clinical Infection, Microbiology, and Immunology, Institute for Infection, Veterinary, and Ecological Sciences (IVES), University of Liverpool, Liverpool, United Kingdom
| | - Rebecca J Bennett
- Department of Clinical Infection, Microbiology, and Immunology, Institute for Infection, Veterinary, and Ecological Sciences (IVES), University of Liverpool, Liverpool, United Kingdom
| | - Lauriane Kuhn
- Plateforme protéomique Strasbourg Esplanade FR1589 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Patryk Ngondo
- Université de Strasbourg, CNRS, Architecture et Réactivité de l'ARN, UPR9002, F-67000, Strasbourg, France
| | - Lorine Debande
- Université de Strasbourg, CNRS, Architecture et Réactivité de l'ARN, UPR9002, F-67000, Strasbourg, France
| | - Elisabeth Njamkepo
- Institut Pasteur, Université Paris Cité, Unité des Bactéries pathogènes entériques, Centre National de Référence des Escherichia coli, Shigella et Salmonella, Paris, F-75015, France
| | - Brian Ho
- Institute of Structural and Molecular Biology, University College London and Birkbeck, London, UK
| | - François-Xavier Weill
- Institut Pasteur, Université Paris Cité, Unité des Bactéries pathogènes entériques, Centre National de Référence des Escherichia coli, Shigella et Salmonella, Paris, F-75015, France
| | - Benoît S Marteyn
- Université de Strasbourg, CNRS, Architecture et Réactivité de l'ARN, UPR9002, F-67000, Strasbourg, France
| | - Claire Jenkins
- Gastro and Food Safety (One Health) Division, UK Health Security Agency, Colindale, London, UK
| | - Kate S Baker
- Department of Clinical Infection, Microbiology, and Immunology, Institute for Infection, Veterinary, and Ecological Sciences (IVES), University of Liverpool, Liverpool, United Kingdom; Department of Genetics, University of Cambridge, Downing Place, Cambridge, UK.
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6
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Chepsergon J, Moleleki LN. Rhizosphere bacterial interactions and impact on plant health. Curr Opin Microbiol 2023; 73:102297. [PMID: 37002974 DOI: 10.1016/j.mib.2023.102297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 01/30/2023] [Accepted: 02/24/2023] [Indexed: 04/01/2023]
Abstract
The rhizosphere is a chemically complex environment that harbors a strikingly diverse microbial community. The past few decades have seen a rapid growth in the body of literature on plant-microbe-microbe interactions and plant health. Thus, the aim of this paper is to review current knowledge on plant-microbe-microbe (specifically bacteria) interactions in the rhizosphere and how these influence rhizosphere microbiomes and impact plant health. This article discusses (i) how the plant recruits beneficial rhizosphere bacteria and ii) how competition between rhizosphere bacteria and mechanisms/weapons employed in bacteria-bacteria competition shapes rhizosphere microbiome and in turn affects plant heath. The discussion mainly focuses on interference competition, characterized by production of specialized metabolites (antibacterial compounds) and exploitative competition where a bacterial strain restricts the competitor's access to nutrients such as through secretion of siderophores that could allude to cooperation. Understanding mechanisms employed in bacteria-bacteria and plant-bacteria interactions could provide insights into how to manipulate microbiomes for improved agricultural outcomes.
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7
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Castillo-Ruiz M, Daille LK, Machuca P, Bittner M. Antibacterial activity of a complex bacteriocin secreted by Staphylococcus epidermidis against Porphyromonas gingivalis. Arch Oral Biol 2023; 152:105730. [PMID: 37209589 DOI: 10.1016/j.archoralbio.2023.105730] [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: 12/21/2022] [Revised: 03/24/2023] [Accepted: 05/15/2023] [Indexed: 05/22/2023]
Abstract
OBJECTIVE To characterize the inhibitory activity of a novel bacteriocin produced by Staphylococcus epidermidis against this periodontal pathogen. DESIGN The bacteriocin activity was evaluated by the agar diffusion method over a lawn of P. gingivalis ATCC 33277. The bacteriocin was purified by Reverse Phase-High Performance Liquid Chromatography (RP-HPLC) and Matrix Assisted Laser Desorption Ionization -Time of Flight Mass Spectrometry (MALDI-TOF-MS). In addition, the bacteriocin host specificity, production on different media cultures and susceptibility to enzymes, pH, and heat treatment were determined. RESULTS The bacteriocin BAC 14990 was selective to P. gingivalis, suggesting a narrow activity range. The production during the growth curve indicated that S. epidermidis had a continued production of this antimicrobial, showing the highest concentration in the stationary phase. The purification of BAC 14990 showed that bacteriocin had a molecular mass of 5795 Da. BAC 14990 was partially resistant to the treatment with proteinase K and papain, however, was fully susceptible to amylase treatment indicating the presence of sugar residues in the protein, suggesting a conjugated type of bacteriocin. Also, this diffusible inhibitory substance was heat and pH treatment resistant. CONCLUSIONS The results indicate the isolation of a new staphylococcal complex bacteriocin that is able to eliminate a Gram-negative bacterium. These results could contribute to the development of treatments directed against pathogens in mixed communities, as is the case with oral diseases.
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Affiliation(s)
- Mario Castillo-Ruiz
- Departamento de Ciencias Químicas y Biológicas, Facultad de Ciencias de la Salud, Universidad Bernardo O'Higgins, General Gana 1702, Santiago 8370854, Chile; Chile Escuela de Química y Farmacia, Facultad de Medicina, Universidad Andres Bello, Sazié 2320, Santiago 8370134, Chile
| | - Leslie K Daille
- Centro GEMA-Genómica, Ecología & Medio Ambiente, Universidad Mayor, Camino La Pirámide 5750, Santiago 8580745, Chile
| | - Pamela Machuca
- Laboratorio de Microbiología y Biotecnología Oral, Facultad de Ciencias de la Vida, Universidad Andres Bello, Echaurren 237, 8370133 Santiago, Chile
| | - Mauricio Bittner
- Laboratorio de Microbiología y Biotecnología Oral, Facultad de Ciencias de la Vida, Universidad Andres Bello, Echaurren 237, 8370133 Santiago, Chile; Facultad de Odontología, Universidad Andres Bello, Echaurren 237, Santiago 8370133, Chile.
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8
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Kuhn T, Junier P, Bshary R, Terrettaz C, Gonzalez D, Richter XYL. Nutrients and flow shape the cyclic dominance games between Escherichia coli strains. Philos Trans R Soc Lond B Biol Sci 2023; 378:20210503. [PMID: 36934746 PMCID: PMC10024984 DOI: 10.1098/rstb.2021.0503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/20/2023] Open
Abstract
Evolutionary game theory has provided various models to explain the coexistence of competing strategies, one of which is the rock-paper-scissors (RPS) game. A system of three Escherichia coli strains-a toxin-producer, a resistant and a sensitive-has become a classic experimental model for studying RPS games. Previous experimental and theoretical studies, however, often ignored the influence of ecological factors such as nutrients and toxin dynamics on the evolutionary game dynamics. In this work, we combine experiments and modelling to study how these factors affect competition dynamics. Using three-dimensional printed mini-bioreactors, we tracked the frequency of the three strains in different culturing media and under different flow regimes. Although our experimental system fulfilled the requirements of cyclic dominance, we did not observe clear cycles or long-term coexistence between strains. We found that both nutrients and flow rates strongly impacted population dynamics. In our simulations, we explicitly modelled the release, removal and diffusion of toxin. We showed that the amount of toxin that is retained in the system is a simple indicator that can predict competition outcomes across broad parameter space. Moreover, our simulation results suggest that high rates of toxin diffusion might have prevented cyclic patterns from emerging in our experimental system. This article is part of the theme issue 'Half a century of evolutionary games: a synthesis of theory, application and future directions'.
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Affiliation(s)
- Thierry Kuhn
- Institute of Biology, University of Neuchâtel, Rue Emile-Argand 11, 2000 Neuchâtel, Switzerland
| | - Pilar Junier
- Institute of Biology, University of Neuchâtel, Rue Emile-Argand 11, 2000 Neuchâtel, Switzerland
| | - Redouan Bshary
- Institute of Biology, University of Neuchâtel, Rue Emile-Argand 11, 2000 Neuchâtel, Switzerland
| | - Céline Terrettaz
- Institute of Biology, University of Neuchâtel, Rue Emile-Argand 11, 2000 Neuchâtel, Switzerland
| | - Diego Gonzalez
- Institute of Biology, University of Neuchâtel, Rue Emile-Argand 11, 2000 Neuchâtel, Switzerland
| | - Xiang-Yi Li Richter
- Institute of Biology, University of Neuchâtel, Rue Emile-Argand 11, 2000 Neuchâtel, Switzerland
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Laganenka L, Lee JW, Malfertheiner L, Dieterich CL, Fuchs L, Piel J, von Mering C, Sourjik V, Hardt WD. Chemotaxis and autoinducer-2 signalling mediate colonization and contribute to co-existence of Escherichia coli strains in the murine gut. Nat Microbiol 2023; 8:204-217. [PMID: 36624229 DOI: 10.1038/s41564-022-01286-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 11/09/2022] [Indexed: 01/11/2023]
Abstract
Bacteria communicate and coordinate their behaviour at the intra- and interspecies levels by producing and sensing diverse extracellular small molecules called autoinducers. Autoinducer 2 (AI-2) is produced and detected by a variety of bacteria and thus plays an important role in interspecies communication and chemotaxis. Although AI-2 is a major autoinducer molecule present in the mammalian gut and can influence the composition of the murine gut microbiota, its role in bacteria-bacteria and bacteria-host interactions during gut colonization remains unclear. Combining competitive infections in C57BL/6 mice with microscopy and bioinformatic approaches, we show that chemotaxis (cheY) and AI-2 signalling (via lsrB) promote gut colonization by Escherichia coli, which is in turn connected to the ability of the bacteria to utilize fructoselysine (frl operon). We further show that the genomic diversity of E. coli strains with respect to AI-2 signalling allows ecological niche segregation and stable co-existence of different E. coli strains in the mammalian gut.
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Affiliation(s)
- Leanid Laganenka
- Institute of Microbiology, D-BIOL, ETH Zurich, Zurich, Switzerland
| | - Jae-Woo Lee
- Max Planck Institute for Terrestrial Microbiology and Center for Synthetic Microbiology, Marburg, Germany
| | - Lukas Malfertheiner
- Department of Molecular Life Sciences and Swiss Institute of Bioinformatics, University of Zurich, Zurich, Switzerland
| | | | - Lea Fuchs
- Institute of Microbiology, D-BIOL, ETH Zurich, Zurich, Switzerland
| | - Jörn Piel
- Institute of Microbiology, D-BIOL, ETH Zurich, Zurich, Switzerland
| | - Christian von Mering
- Department of Molecular Life Sciences and Swiss Institute of Bioinformatics, University of Zurich, Zurich, Switzerland
| | - Victor Sourjik
- Max Planck Institute for Terrestrial Microbiology and Center for Synthetic Microbiology, Marburg, Germany
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Yun HS, Kim DH, Kim JG, Kim YS, Yoon HS. The microbial communities (bacteria, algae, zooplankton, and fungi) improved biofloc technology including the nitrogen-related material cycle in Litopenaeus vannamei farms. Front Bioeng Biotechnol 2022; 10:883522. [PMID: 36507271 PMCID: PMC9727081 DOI: 10.3389/fbioe.2022.883522] [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: 02/25/2022] [Accepted: 11/08/2022] [Indexed: 11/24/2022] Open
Abstract
Microbes are essential in biofloc technology for controlling nitrogen levels in water. The composition and function of microorganisms with biofloc systems were reported; however, data on microorganisms other than bacteria, such as algae (which are essential in the nitrogen cycle) and zooplankton (which are bacterial and algal predators), remain limited. The microbial communities (including bacteria, algae, zooplankton, and fungi) were investigated in shrimp farms using biofloc technology. Using Illumina MiSeq sequencing, the V4 region of 18S rRNA and the V3-V4 region of 16S rRNA were utilized for the analysis of the eukaryotic and prokaryotic microbial communities. As a result, it was found that the biofloc in the shrimp farm consisted of 48.73%-73.04% eukaryotic organisms and 26.96%-51.27% prokaryotic organisms. In these shrimp farms, prokaryotic microbial communities had higher specie richness and diversity than eukaryotic microbial communities. However, the eukaryotic microbial communities were more abundant than their prokaryotic counterparts, while algae and zooplankton dominated them. It was discovered that the structures of the microbial communities in the shrimp farms seemed to depend on the effects of predation by zooplankton and other related organisms. The results provided the nitrogen cycle in biofloc systems by the algal and bacterial groups in microbial communities.
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Affiliation(s)
- Hyun-Sik Yun
- Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, South Korea
| | - Dong-Hyun Kim
- School of Applied Biosciences, Kyungpook National University, Daegu, South Korea
| | - Jong-Guk Kim
- School of Applied Biosciences, Kyungpook National University, Daegu, South Korea,School of Life Sciences and Biotechnology, BK21 Plus KNU Creative BioResearch Group, Kyungpook National University, Daegu, South Korea,*Correspondence: Jong-Guk Kim, ; Young-Saeng Kim, ; Ho-Sung Yoon,
| | - Young-Saeng Kim
- Research Institute of Ulleung-do & Dok-do, Kyungpook National University, Daegu, South Korea,*Correspondence: Jong-Guk Kim, ; Young-Saeng Kim, ; Ho-Sung Yoon,
| | - Ho-Sung Yoon
- Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, South Korea,School of Life Sciences and Biotechnology, BK21 Plus KNU Creative BioResearch Group, Kyungpook National University, Daegu, South Korea,Advanced Bio-Resource Research Center, Kyungpook National University, Daegu, South Korea,*Correspondence: Jong-Guk Kim, ; Young-Saeng Kim, ; Ho-Sung Yoon,
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11
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Alloul A, Van Kampen W, Cerruti M, Wittouck S, Pabst M, Weissbrodt D. Exploring the role of antimicrobials in the selective growth of purple phototrophic bacteria through genome mining and agar spot assays. Lett Appl Microbiol 2022; 75:1275-1285. [PMID: 35938312 PMCID: PMC9804395 DOI: 10.1111/lam.13795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 06/30/2022] [Accepted: 07/19/2022] [Indexed: 01/05/2023]
Abstract
Purple non-sulphur bacteria (PNSB) are an emerging group of microbes attractive for applied microbiology applications such as wastewater treatment, plant biostimulants, microbial protein, polyhydroxyalkanoates and H2 production. These photoorganoheterotrophic microbes have the unique ability to grow selectively on organic carbon in anaerobic photobioreactors. This so-called selectivity implies that the microbial community will have a low diversity and a high abundance of a particular PNSB species. Recently, it has been shown that certain PNSB strains can produce antimicrobials, yet it remains unclear whether these contribute to competitive inhibition. This research aimed to understand which type of antimicrobial PNSB produce and identify whether these compounds contribute to their selective growth. Mining 166 publicly-available PNSB genomes using the computational tool BAGEL showed that 59% contained antimicrobial encoding regions, more specifically biosynthetic clusters of bacteriocins and non-ribosomal peptide synthetases. Inter- and intra-species inhibition was observed in agar spot assays for Rhodobacter blasticus EBR2 and Rhodopseudomonas palustris EBE1 with inhibition zones of, respectively, 5.1 and 1.5-5.7 mm. Peptidomic analysis detected a peptide fragment in the supernatant (SVLQLLR) that had a 100% percentage identity match with a known non-ribosomal peptide synthetase with antimicrobial activity.
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Affiliation(s)
- A. Alloul
- Department of BiotechnologyDelft University of TechnologyDelftthe Netherlands,Department of Bioscience EngineeringUniversity of AntwerpAntwerpenBelgium
| | - W. Van Kampen
- Department of BiotechnologyDelft University of TechnologyDelftthe Netherlands
| | - M. Cerruti
- Department of BiotechnologyDelft University of TechnologyDelftthe Netherlands
| | - S. Wittouck
- Department of Bioscience EngineeringUniversity of AntwerpAntwerpenBelgium
| | - M. Pabst
- Department of BiotechnologyDelft University of TechnologyDelftthe Netherlands
| | - D.G. Weissbrodt
- Department of BiotechnologyDelft University of TechnologyDelftthe Netherlands
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12
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Ehau‐Taumaunu H, Hockett KL. The plant host environment influences competitive interactions between bacterial pathogens. ENVIRONMENTAL MICROBIOLOGY REPORTS 2022; 14:785-794. [PMID: 35700743 PMCID: PMC9796116 DOI: 10.1111/1758-2229.13103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 05/31/2022] [Accepted: 06/02/2022] [Indexed: 06/15/2023]
Abstract
Bacteria compete for resources in diverse environments using an array of antagonistic strategies, including the production of narrow-spectrum protein antibacterials termed bacteriocins. Although significant research has focused on bacteriocin-mediated dynamics in culture environments, little research has explored bacteriocin-mediated dynamics within a host context, particularly in plant environments. Here, we show that a bacterial plant pathogen, Pseudomonas syringae pv. syringae (Psy), expresses a bacteriocin both in culture and in leaf apoplast when co-inoculated with a bacteriocin-sensitive competitor, P. syringae pv. phaseolicola (Pph). Although there is an observable negative effect of the bacteriocin on the Pph population at most time points both in culture and in the leaf apoplast, a bacteriocin-mediated benefit to Psy was only observed when the producing strain was co-infiltrated at a low population frequency (1:9) into the leaf apoplast. At 6 days post-infiltration, Psy achieved an eightfold population increase compared to a bacteriocin-deficient mutant in the apoplast. No bacteriocin-mediated benefit for Psy was observed under the culture conditions tested. Additionally, we found that the bacteriocin-mediated benefit for Psy was dependent on the Type III Secretion System. Taken together, our results demonstrate that the fitness benefit of bacteriocin-mediated antagonism is influenced by interactions within the host plant.
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Affiliation(s)
- Hanareia Ehau‐Taumaunu
- Department of Plant Pathology and Environmental MicrobiologyThe Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA
| | - Kevin L. Hockett
- Department of Plant Pathology and Environmental MicrobiologyThe Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA
- Center for Infectious Diseases DynamicsThe Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA
- The Huck Institutes of the Life SciencesThe Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA
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13
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Jautzus T, van Gestel J, Kovács ÁT. Complex extracellular biology drives surface competition during colony expansion in Bacillus subtilis. THE ISME JOURNAL 2022; 16:2320-2328. [PMID: 35790818 PMCID: PMC9477810 DOI: 10.1038/s41396-022-01279-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 06/13/2022] [Accepted: 06/20/2022] [Indexed: 04/29/2023]
Abstract
Many bacteria grow on surfaces in nature, where they form cell collectives that compete for space. Within these collectives, cells often secrete molecules that benefit surface spreading by, for example, reducing surface tension or promoting filamentous growth. Although we have a detailed understanding of how these molecules are produced, much remains unknown about their role in surface competition. Here we examine sliding motility in Bacillus subtilis and compare how secreted molecules, essential for sliding, affect intraspecific cooperation and competition on a surface. We specifically examine (i) the lipopeptide surfactin, (ii) the hydrophobin protein BslA, and (iii) exopolysaccharides (EPS). We find that these molecules have a distinct effect on surface competition. Whereas surfactin acts like a common good, which is costly to produce and benefits cells throughout the surface, BslA and EPS are cost-free and act locally. Accordingly, surfactin deficient mutants can exploit the wild-type strain in competition for space, while BslA and EPS mutants cannot. Supported by a mathematical model, we show that three factors are important in predicting the outcome of surface competition: the costs of molecule synthesis, the private benefits of molecule production, and the diffusion rate. Our results underscore the intricate extracellular biology that can drive bacterial surface competition.
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Affiliation(s)
- Theresa Jautzus
- Terrestrial Biofilms Group, Institute of Microbiology, Friedrich Schiller University Jena, 07743, Jena, Germany
| | - Jordi van Gestel
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA, 94158, USA
| | - Ákos T Kovács
- Terrestrial Biofilms Group, Institute of Microbiology, Friedrich Schiller University Jena, 07743, Jena, Germany.
- Bacterial Interactions and Evolution Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800, Kgs. Lyngby, Denmark.
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14
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Palmer JD, Foster KR. The evolution of spectrum in antibiotics and bacteriocins. Proc Natl Acad Sci U S A 2022; 119:e2205407119. [PMID: 36099299 PMCID: PMC9499554 DOI: 10.1073/pnas.2205407119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 08/05/2022] [Indexed: 12/02/2022] Open
Abstract
A key property of many antibiotics is that they will kill or inhibit a diverse range of microbial species. This broad-spectrum of activity has its evolutionary roots in ecological competition, whereby bacteria and other microbes use antibiotics to suppress other strains and species. However, many bacteria also use narrow-spectrum toxins, such as bacteriocins, that principally target conspecifics. Why has such a diversity in spectrum evolved? Here, we develop an evolutionary model to understand antimicrobial spectrum. Our first model recapitulates the intuition that broad-spectrum is best, because it enables a microbe to kill a wider diversity of competitors. However, this model neglects an important property of antimicrobials: They are commonly bound, sequestered, or degraded by the cells they target. Incorporating this toxin loss reveals a major advantage to narrow-spectrum toxins: They target the strongest ecological competitor and avoid being used up on less important species. Why then would broad-spectrum toxins ever evolve? Our model predicts that broad-spectrum toxins will be favored by natural selection if a strain is highly abundant and can overpower both its key competitor and other species. We test this prediction by compiling and analyzing a database of the regulation and spectrum of toxins used in inter-bacterial competition. This analysis reveals a strong association between broad-spectrum toxins and density-dependent regulation, indicating that they are indeed used when strains are abundant. Our work provides a rationale for why bacteria commonly evolve narrow-spectrum toxins such as bacteriocins and suggests that the evolution of antibiotics proper is a signature of ecological dominance.
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Affiliation(s)
- Jacob D. Palmer
- Department of Biology, University of Oxford, Oxford, OX1 3RB, United Kingdom
- Department of Biochemistry, University of Oxford, Oxford, OX1 3QU, United Kingdom
| | - Kevin R. Foster
- Department of Biology, University of Oxford, Oxford, OX1 3RB, United Kingdom
- Department of Biochemistry, University of Oxford, Oxford, OX1 3QU, United Kingdom
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15
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Cavallaro A, Rhoads WJ, Huwiler SG, Stachler E, Hammes F. Potential probiotic approaches to control Legionella in engineered aquatic ecosystems. FEMS Microbiol Ecol 2022; 98:6604835. [PMID: 35679082 PMCID: PMC9333994 DOI: 10.1093/femsec/fiac071] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 05/20/2022] [Accepted: 06/07/2022] [Indexed: 11/25/2022] Open
Abstract
Opportunistic pathogens belonging to the genus Legionella are among the most reported waterborne-associated pathogens in industrialized countries. Legionella colonize a variety of engineered aquatic ecosystems and persist in biofilms where they interact with a multitude of other resident microorganisms. In this review, we assess how some of these interactions could be used to develop a biological-driven “probiotic” control approach against Legionella. We focus on: (i) mechanisms limiting the ability of Legionella to establish and replicate within some of their natural protozoan hosts; (ii) exploitative and interference competitive interactions between Legionella and other microorganisms; and (iii) the potential of predatory bacteria and phages against Legionella. This field is still emergent, and we therefore specifically highlight research for future investigations, and propose perspectives on the feasibility and public acceptance of a potential probiotic approach.
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Affiliation(s)
- Alessio Cavallaro
- Department of Environmental Microbiology, Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland.,Department of Environmental Systems Science, Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, 8092 Zurich, Switzerland
| | - William J Rhoads
- Department of Environmental Microbiology, Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland
| | - Simona G Huwiler
- Department of Plant and Microbial Biology, University of Zurich, 8008 Zurich, Switzerland
| | - Elyse Stachler
- Department of Environmental Microbiology, Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland
| | - Frederik Hammes
- Department of Environmental Microbiology, Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland
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16
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De Wit G, Svet L, Lories B, Steenackers HP. Microbial Interspecies Interactions and Their Impact on the Emergence and Spread of Antimicrobial Resistance. Annu Rev Microbiol 2022; 76:179-192. [PMID: 35609949 DOI: 10.1146/annurev-micro-041320-031627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Bacteria are social organisms that commonly live in dense communities surrounded by a multitude of other species. The competitive and cooperative interactions between these species not only shape the bacterial communities but also influence their susceptibility to antimicrobials. While several studies have shown that mixed-species communities are more tolerant toward antimicrobials than their monospecies counterparts, only limited empirical data are currently available on how interspecies interactions influence resistance development. We here propose a theoretic framework outlining the potential impact of interspecies social behavior on different aspects of resistance development. We identify factors by which interspecies interactions might influence resistance evolution and distinguish between their effect on (a) the emergence of a resistant mutant and (b) the spread of this resistance throughout the population. Our analysis indicates that considering the social life of bacteria is imperative to the rational design of more effective antibiotic treatment strategies with a minimal hazard for resistance development. Expected final online publication date for the Annual Review of Microbiology, Volume 76 is September 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Gitta De Wit
- Centre of Microbial and Plant Genetics (CMPG), Department of Microbial and Molecular Systems, KU Leuven, 3001 Leuven, Belgium; , , ,
| | - Luka Svet
- Centre of Microbial and Plant Genetics (CMPG), Department of Microbial and Molecular Systems, KU Leuven, 3001 Leuven, Belgium; , , ,
| | - Bram Lories
- Centre of Microbial and Plant Genetics (CMPG), Department of Microbial and Molecular Systems, KU Leuven, 3001 Leuven, Belgium; , , ,
| | - Hans P Steenackers
- Centre of Microbial and Plant Genetics (CMPG), Department of Microbial and Molecular Systems, KU Leuven, 3001 Leuven, Belgium; , , ,
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17
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Abstract
Nematode predation plays an essential role in determining changes in the rhizosphere microbiome. These changes affect the local nutrient balance and cycling of essential nutrients by selectively structuring interactions across functional taxa in the system. Currently, it is largely unknown to what extent nematode predation induces shifts in the microbiome associated with different rates of soil phosphorous (P) mineralization. Here, we performed an 7-year field experiment to investigate the importance of nematode predation influencing P availability and cycling. These were tracked via the changes in the alkaline phosphomonoesterase (ALP)-producing bacterial community and ALP activity in the rhizosphere of rapeseed. Here, we found that the nematode addition led to high predation pressure and thereby caused shifts in the abundance and composition of the ALP-producing bacterial community. Further analyses based on cooccurrence networks and metabolomics consistently showed that nematode addition induced competitive interactions between potentially keystone ALP-producing bacteria and other members within the community. Structural equation modeling revealed that the outcome of this competition induced by stronger predation pressure of nematodes was significantly associated with higher diversity of ALP-producing bacteria, thereby enhancing ALP activity and P availability. Taken together, our results provide evidence for the importance of predator-prey and competitive interactions in soil biology and their direct influences on nutrient cycling dynamics.
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18
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TisB Protein Protects Escherichia coli Cells Suffering Massive DNA Damage from Environmental Toxic Compounds. mBio 2022; 13:e0038522. [PMID: 35377167 PMCID: PMC9040746 DOI: 10.1128/mbio.00385-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Toxin-antitoxin systems are genetic elements that are widespread in prokaryotes. Although molecular mode of action of many of these toxins has been identified, their biological functions are mostly unknown. We investigated the functional integration of the TisB/IstR toxin-antitoxin system in the Escherichia coli SOS genotoxic stress response network. We showed that the tisB gene is induced in cells exposed to high doses of the genotoxic antibiotic trimethoprim. However, we also found that TisB contributes to trimethoprim-induced lethality. This is a consequence of the TisB-induced drop in the proton motive force (PMF), which results in blocking the thymine import and therefore the functioning of the pyrimidine salvage pathway. Conversely, a TisB-induced PMF drop protects cells by preventing the import of some other toxic compounds, like the aminoglycoside antibiotic gentamicin and colicin M, in the SOS-induced cells. Colicins are cytotoxic molecules produced by Enterobacterales when they are exposed to strong genotoxic stresses in order to compete with other microbiota members. We indeed found that TisB contributes to E. coli’s fitness during mouse gut colonization. Based on the results obtained here, we propose that the primary biological role of the TisB toxin is to increase the probability of survival and maintenance in the mammalian gut of their bacterial hosts when they have to simultaneously deal with massive DNA damages and a fierce chemical warfare with other microbiota members.
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19
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Wu Y, Pang X, Wu Y, Liu X, Zhang X. Enterocins: Classification, Synthesis, Antibacterial Mechanisms and Food Applications. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27072258. [PMID: 35408657 PMCID: PMC9000605 DOI: 10.3390/molecules27072258] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Revised: 03/23/2022] [Accepted: 03/28/2022] [Indexed: 01/15/2023]
Abstract
Enterococci, a type of lactic acid bacteria, are widely distributed in various environments and are part of the normal flora in the intestinal tract of humans and animals. Although enterococci have gradually evolved pathogenic strains causing nosocomial infections in recent years, the non-pathogenic strains have still been widely used as probiotics and feed additives. Enterococcus can produce enterocin, which are bacteriocins considered as ribosomal peptides that kill or inhibit the growth of other microorganisms. This paper reviews the classification, synthesis, antibacterial mechanisms and applications of enterocins, and discusses the prospects for future research.
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Affiliation(s)
- Yajing Wu
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou 310058, China; (Y.W.); (X.P.); (Y.W.); (X.L.)
| | - Xinxin Pang
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou 310058, China; (Y.W.); (X.P.); (Y.W.); (X.L.)
| | - Yansha Wu
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou 310058, China; (Y.W.); (X.P.); (Y.W.); (X.L.)
| | - Xiayu Liu
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou 310058, China; (Y.W.); (X.P.); (Y.W.); (X.L.)
| | - Xinglin Zhang
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou 310058, China; (Y.W.); (X.P.); (Y.W.); (X.L.)
- College of Agriculture and Forestry, Linyi University, Linyi 276005, China
- Correspondence: ; Tel.: +86-571-86984316
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20
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LAMBERTI MÓNICAFTORREZ, LÓPEZ FABIÁNE, PESCARETTI MARÍADELASMERCEDES, DELGADO MÓNICAA. Characterization of a bacteriocin produced by a clinical isolate of Shigella flexneri 2. AN ACAD BRAS CIENC 2022. [DOI: 10.1590/0001-3765202220200982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
| | - FABIÁN E. LÓPEZ
- Instituto Superior de Investigaciones Biológicas (INSIBIO), Argentina; Universidad Nacional de Chilecito (UNdeC), Argentina
| | | | - MÓNICA A. DELGADO
- Instituto Superior de Investigaciones Biológicas (INSIBIO), Argentina
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21
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Li Q, Liu L, Guo A, Zhang X, Liu W, Ruan Y. Formation of Multispecies Biofilms and Their Resistance to Disinfectants in Food Processing Environments: A Review. J Food Prot 2021; 84:2071-2083. [PMID: 34324690 DOI: 10.4315/jfp-21-071] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Accepted: 07/16/2021] [Indexed: 11/11/2022]
Abstract
ABSTRACT In food processing environments, various microorganisms can adhere and aggregate on the surface of equipment, resulting in the formation of multispecies biofilms. Complex interactions among microorganisms may affect the formation of multispecies biofilms and resistance to disinfectants, which are food safety and quality concerns. This article reviews the various interactions among microorganisms in multispecies biofilms, including competitive, cooperative, and neutral interactions. Then, the preliminary mechanisms underlying the formation of multispecies biofilms are discussed in relation to factors, such as quorum-sensing signal molecules, extracellular polymeric substances, and biofilm-regulated genes. Finally, the resistance mechanisms of common contaminating microorganisms to disinfectants in food processing environments are also summarized. This review is expected to facilitate a better understanding of interspecies interactions and provide some implications for the control of multispecies biofilms in food processing. HIGHLIGHTS
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Affiliation(s)
- Qun Li
- College of Food Science and Technology, Huazhong Agriculture University, Wuhan, Hubei 430070, People's Republic of China
| | - Ling Liu
- College of Food Science and Technology, Huazhong Agriculture University, Wuhan, Hubei 430070, People's Republic of China
| | - Ailing Guo
- College of Food Science and Technology, Huazhong Agriculture University, Wuhan, Hubei 430070, People's Republic of China.,National Research and Development Center for Egg Processing, Wuhan, Hubei 430070, People's Republic of China
| | - Xinshuai Zhang
- College of Food Science and Technology, Huazhong Agriculture University, Wuhan, Hubei 430070, People's Republic of China
| | - Wukang Liu
- College of Food Science and Technology, Huazhong Agriculture University, Wuhan, Hubei 430070, People's Republic of China
| | - Yao Ruan
- College of Food Science and Technology, Huazhong Agriculture University, Wuhan, Hubei 430070, People's Republic of China
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22
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Abram F, Arcari T, Guerreiro D, O'Byrne CP. Evolutionary trade-offs between growth and survival: The delicate balance between reproductive success and longevity in bacteria. Adv Microb Physiol 2021; 79:133-162. [PMID: 34836610 DOI: 10.1016/bs.ampbs.2021.07.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
All living cells strive to allocate cellular resources in a way that promotes maximal evolutionary fitness. While there are many competing demands for resources the main decision making process centres on whether to proceed with growth and reproduction or to "hunker down" and invest in protection and survival (or to strike an optimal balance between these two processes). The transcriptional programme active at any given time largely determines which of these competing processes is dominant. At the top of the regulatory hierarchy are the sigma factors that commandeer the transcriptional machinery and determine which set of promoters are active at any given time. The regulatory inputs controlling their activity are therefore often highly complex, with multiple layers of regulation, allowing relevant environmental information to produce the most beneficial response. The tension between growth and survival is also evident in the developmental programme necessary to promote biofilm formation, which is typically associated with low growth rates and enhanced long-term survival. Nucleotide second messengers and energy pools (ATP/ADP levels) play critical roles in determining the fate of individual cells. Regulatory small RNAs frequently play important roles in the decision making processes too. In this review we discuss the trade-off that exists between reproduction and persistence in bacteria and discuss some of the recent advances in this fascinating field.
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Affiliation(s)
- Florence Abram
- Microbiology & Ryan Institute, School of Natural Sciences, National University of Ireland, Galway, Ireland
| | - Talia Arcari
- Microbiology & Ryan Institute, School of Natural Sciences, National University of Ireland, Galway, Ireland
| | - Duarte Guerreiro
- Microbiology & Ryan Institute, School of Natural Sciences, National University of Ireland, Galway, Ireland
| | - Conor P O'Byrne
- Microbiology & Ryan Institute, School of Natural Sciences, National University of Ireland, Galway, Ireland.
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23
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Heilbronner S, Krismer B, Brötz-Oesterhelt H, Peschel A. The microbiome-shaping roles of bacteriocins. Nat Rev Microbiol 2021; 19:726-739. [PMID: 34075213 DOI: 10.1038/s41579-021-00569-w] [Citation(s) in RCA: 106] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/26/2021] [Indexed: 02/05/2023]
Abstract
The microbiomes on human body surfaces affect health in multiple ways. They include not only commensal or mutualistic bacteria but also potentially pathogenic bacteria, which can enter sterile tissues to cause invasive infection. Many commensal bacteria produce small antibacterial molecules termed bacteriocins that have the capacity to eliminate specific colonizing pathogens; as such, bacteriocins have attracted increased attention as potential microbiome-editing tools. Metagenome-based and activity-based screening approaches have strongly expanded our knowledge of the abundance and diversity of bacteriocin biosynthetic gene clusters and the properties of a continuously growing list of bacteriocin classes. The dynamic acquisition, diversification or loss of bacteriocin genes can shape the fitness of a bacterial strain that is in competition with bacteriocin-susceptible bacteria. However, a bacteriocin can only provide a competitive advantage if its fitness benefit exceeds the metabolic cost of production, if it spares crucial mutualistic partner strains and if major competitors cannot develop resistance. In contrast to most currently available antibiotics, many bacteriocins have only narrow activity ranges and could be attractive agents for precision therapy and prevention of infections. A common scientific strategy involving multiple disciplines is needed to uncover the immense potential of microbiome-shaping bacteriocins.
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Affiliation(s)
- Simon Heilbronner
- Interfaculty Institute of Microbiology and Infection Medicine, Department of Infection Biology, University of Tübingen, Tübingen, Germany. .,Cluster of Excellence EXC 2124 Controlling Microbes to Fight Infections, University of Tübingen, Tübingen, Germany.
| | - Bernhard Krismer
- Interfaculty Institute of Microbiology and Infection Medicine, Department of Infection Biology, University of Tübingen, Tübingen, Germany.,Cluster of Excellence EXC 2124 Controlling Microbes to Fight Infections, University of Tübingen, Tübingen, Germany
| | - Heike Brötz-Oesterhelt
- Cluster of Excellence EXC 2124 Controlling Microbes to Fight Infections, University of Tübingen, Tübingen, Germany.,Interfaculty Institute of Microbiology and Infection Medicine, Department of Microbial Bioactive Compounds, University of Tübingen, Tübingen, Germany
| | - Andreas Peschel
- Interfaculty Institute of Microbiology and Infection Medicine, Department of Infection Biology, University of Tübingen, Tübingen, Germany. .,Cluster of Excellence EXC 2124 Controlling Microbes to Fight Infections, University of Tübingen, Tübingen, Germany.
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24
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Early development of the skin microbiome: therapeutic opportunities. Pediatr Res 2021; 90:731-737. [PMID: 32919387 PMCID: PMC7952468 DOI: 10.1038/s41390-020-01146-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 07/23/2020] [Accepted: 08/16/2020] [Indexed: 02/06/2023]
Abstract
As human skin hosts a diverse microbiota in health and disease, there is an emerging consensus that dysregulated interactions between host and microbiome may contribute to chronic inflammatory disease of the skin. Neonatal skin is a unique habitat, structurally similar to the adult but with a different profile of metabolic substrates, environmental stressors, and immune activity. The surface is colonized within moments of birth with a bias toward maternal strains. Initial colonists are outcompeted as environmental exposures increase and host skin matures. Nonetheless, early life microbial acquisitions may have long-lasting effects on health through modulation of host immunity and competitive interactions between bacteria. Microbial ecology and its influence on health have been of interest to dermatologists for >50 years, and an explosion of recent interest in the microbiome has prompted ongoing investigations of several microbial therapeutics for dermatological disease. In this review, we consider how recent insight into the host and microbial factors driving development of the skin microbiome in early life offers new opportunities for therapeutic intervention. IMPACT: Advancement in understanding molecular mechanisms of bacterial competition opens new avenues of investigation into dermatological disease. Primary development of the skin microbiome is determined by immunological features of the cutaneous habitat. Understanding coordinated microbial and immunological development in the pediatric patient requires a multidisciplinary synthesis of primary literature.
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25
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Sibinelli-Sousa S, de Araújo-Silva AL, Hespanhol JT, Bayer-Santos E. Revisiting the steps of Salmonella gut infection with a focus on antagonistic interbacterial interactions. FEBS J 2021; 289:4192-4211. [PMID: 34546626 DOI: 10.1111/febs.16211] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 09/12/2021] [Accepted: 09/20/2021] [Indexed: 12/20/2022]
Abstract
A commensal microbial community is established in the mammalian gut during its development, and these organisms protect the host against pathogenic invaders. The hallmark of noninvasive Salmonella gut infection is the induction of inflammation via effector proteins secreted by the type III secretion system, which modulate host responses to create a new niche in which the pathogen can overcome the colonization resistance imposed by the microbiota. Several studies have shown that endogenous microbes are important to control Salmonella infection by competing for resources. However, there is limited information about antimicrobial mechanisms used by commensals and pathogens during these in vivo disputes for niche control. This review aims to revisit the steps that Salmonella needs to overcome during gut colonization-before and after the induction of inflammation-to achieve an effective infection. We focus on a series of reported and hypothetical antagonistic interbacterial interactions in which both contact-independent and contact-dependent mechanisms might define the outcome of the infection.
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Affiliation(s)
| | | | - Julia Takuno Hespanhol
- Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, Brazil
| | - Ethel Bayer-Santos
- Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, Brazil
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26
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Worsley SF, Innocent TM, Holmes NA, Al-Bassam MM, Schiøtt M, Wilkinson B, Murrell JC, Boomsma JJ, Yu DW, Hutchings MI. Competition-based screening helps to secure the evolutionary stability of a defensive microbiome. BMC Biol 2021; 19:205. [PMID: 34526023 PMCID: PMC8444595 DOI: 10.1186/s12915-021-01142-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 09/03/2021] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND The cuticular microbiomes of Acromyrmex leaf-cutting ants pose a conundrum in microbiome biology because they are freely colonisable, and yet the prevalence of the vertically transmitted bacteria Pseudonocardia, which contributes to the control of Escovopsis fungus garden disease, is never compromised by the secondary acquisition of other bacterial strains. Game theory suggests that competition-based screening can allow the selective recruitment of antibiotic-producing bacteria from the environment, by providing abundant resources to foment interference competition between bacterial species and by using Pseudonocardia to bias the outcome of competition in favour of antibiotic producers. RESULTS Here, we use RNA-stable isotope probing (RNA-SIP) to confirm that Acromyrmex ants can maintain a range of microbial symbionts on their cuticle by supplying public resources. We then used RNA sequencing, bioassays, and competition experiments to show that vertically transmitted Pseudonocardia strains produce antibacterials that differentially reduce the growth rates of other microbes, ultimately biassing the bacterial competition to allow the selective establishment of secondary antibiotic-producing strains while excluding non-antibiotic-producing strains that would parasitise the symbiosis. CONCLUSIONS Our findings are consistent with the hypothesis that competition-based screening is a plausible mechanism for maintaining the integrity of the co-adapted mutualism between the leaf-cutting ant farming symbiosis and its defensive microbiome. Our results have broader implications for explaining the stability of other complex symbioses involving horizontal acquisition.
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Affiliation(s)
- Sarah F Worsley
- School of Biological Sciences, Norwich Research Park, University of East Anglia, Norwich, Norfolk, NR4 7TJ, UK
| | - Tabitha M Innocent
- Centre for Social Evolution, Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Neil A Holmes
- School of Biological Sciences, Norwich Research Park, University of East Anglia, Norwich, Norfolk, NR4 7TJ, UK
- Department of Molecular Microbiology, John Innes Centre, Norwich Research Park, Norwich, Norfolk, NR4 7UH, UK
| | - Mahmoud M Al-Bassam
- School of Biological Sciences, Norwich Research Park, University of East Anglia, Norwich, Norfolk, NR4 7TJ, UK
| | - Morten Schiøtt
- Centre for Social Evolution, Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Barrie Wilkinson
- Department of Molecular Microbiology, John Innes Centre, Norwich Research Park, Norwich, Norfolk, NR4 7UH, UK
| | - J Colin Murrell
- School of Environmental Sciences, Norwich Research Park, University of East Anglia, Norwich, Norfolk, NR4 7TJ, UK
| | - Jacobus J Boomsma
- Centre for Social Evolution, Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
| | - Douglas W Yu
- School of Biological Sciences, Norwich Research Park, University of East Anglia, Norwich, Norfolk, NR4 7TJ, UK.
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650223, Yunnan, China.
- Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming, 650223, Yunnan, China.
| | - Matthew I Hutchings
- School of Biological Sciences, Norwich Research Park, University of East Anglia, Norwich, Norfolk, NR4 7TJ, UK.
- Department of Molecular Microbiology, John Innes Centre, Norwich Research Park, Norwich, Norfolk, NR4 7UH, UK.
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27
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Fields B, Moffat EK, Harrison E, Andersen SU, Young JPW, Friman VP. Genetic variation is associated with differences in facilitative and competitive interactions in the Rhizobium leguminosarum species complex. Environ Microbiol 2021; 24:3463-3485. [PMID: 34398510 DOI: 10.1111/1462-2920.15720] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 07/08/2021] [Accepted: 08/10/2021] [Indexed: 12/01/2022]
Abstract
Competitive and facilitative interactions influence bacterial community composition, diversity and functioning. However, the role of genetic diversity for determining interactions between coexisting strains of the same, or closely related, species remains poorly understood. Here, we investigated the type (facilitative/inhibitory) and potential underlying mechanisms of pairwise interactions between 24 genetically diverse bacterial strains belonging to three genospecies (gsA,C,E) of the Rhizobium leguminosarum species complex. Interactions were determined indirectly, based on secreted compounds in cell-free supernatants, and directly, as growth inhibition in cocultures. We found supernatants mediated both facilitative and inhibitory interactions that varied greatly between strains and genospecies. Overall, gsE strains indirectly suppressed growth of gsA strains, while their own growth was facilitated by other genospecies' supernatants. Similar genospecies-level patterns were observed in direct competition, where gsA showed the highest susceptibility and gsE the highest inhibition capacity. At the genetic level, increased gsA susceptibility was associated with a non-random distribution of quorum sensing and secondary metabolite genes across genospecies. Together, our results suggest that genetic variation is associated with facilitative and competitive interactions, which could be important ecological mechanisms explaining R. leguminosarum diversity.
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Affiliation(s)
| | - Emma K Moffat
- Department of Biology, University of York, York, UK.,Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK
| | - Ellie Harrison
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK
| | - Stig U Andersen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
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28
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Gjini E, Madec S. The ratio of single to co-colonization is key to complexity in interacting systems with multiple strains. Ecol Evol 2021; 11:8456-8474. [PMID: 34257910 PMCID: PMC8258234 DOI: 10.1002/ece3.7259] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 12/16/2020] [Accepted: 01/12/2021] [Indexed: 11/06/2022] Open
Abstract
The high number and diversity of microbial strains circulating in host populations have motivated extensive research on the mechanisms that maintain biodiversity. However, much of this work focuses on strain-specific and cross-immunity interactions. Another less explored mode of pairwise interaction is via altered susceptibilities to co-colonization in hosts already colonized by one strain. Diversity in such interaction coefficients enables strains to create dynamically their niches for growth and persistence, and "engineer" their common environment. How such a network of interactions with others mediates collective coexistence remains puzzling analytically and computationally difficult to simulate. Furthermore, the gradients modulating stability-complexity regimes in such multi-player endemic systems remain poorly understood. In a recent study (Madec & Gjini, Bulletin of Mathematical Biology, 82), we obtained an analytic representation for N-type coexistence in an SIS epidemiological model with co-colonization. We mapped multi-strain dynamics to a replicator equation using timescale separation. Here, we examine what drives coexistence regimes in such co-colonization system. We find the ratio of single to co-colonization, µ, critically determines the type of equilibrium and number of coexisting strains, and encodes a trade-off between overall transmission intensity R 0 and mean interaction coefficient in strain space, k. Preserving a given coexistence regime, under fixed trait variation, requires balancing between higher mean competition in favorable environments, and higher cooperation in harsher environments, and is consistent with the stress gradient hypothesis. Multi-strain coexistence tends to steady-state attractors for small µ, whereas as µ increases, dynamics tend to more complex attractors. Following strain frequencies, evolutionary dynamics in the system also display contrasting patterns with µ, interpolating between multi-stable and fluctuating selection for cooperation and mean invasion fitness, in the two extremes. This co-colonization framework could be applied more generally, to study invariant principles in collective coexistence, and to quantify how critical shifts in community dynamics get potentiated by mean-field and environmental gradients.
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Affiliation(s)
- Erida Gjini
- Instituto Gulbenkian de CiênciaOeirasPortugal
- Center for Computational and Stochastic MathematicsInstituto Superior TécnicoUniversity of LisbonLisbonPortugal
| | - Sten Madec
- Institut Denis PoissonUniversity of ToursToursFrance
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29
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Alster CJ, Allison SD, Glassman SI, Martiny AC, Treseder KK. Exploring Trait Trade-Offs for Fungal Decomposers in a Southern California Grassland. Front Microbiol 2021; 12:655987. [PMID: 33995318 PMCID: PMC8118720 DOI: 10.3389/fmicb.2021.655987] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 03/05/2021] [Indexed: 11/14/2022] Open
Abstract
Fungi are important decomposers in terrestrial ecosystems, so their responses to climate change might influence carbon (C) and nitrogen (N) dynamics. We investigated whether growth and activity of fungi under drought conditions were structured by trade-offs among traits in 15 fungal isolates from a Mediterranean Southern California grassland. We inoculated fungi onto sterilized litter that was incubated at three moisture levels (4, 27, and 50% water holding capacity, WHC). For each isolate, we characterized traits that described three potential lifestyles within the newly proposed “YAS” framework: growth yield, resource acquisition, and stress tolerance. Specifically, we measured fungal hyphal length per unit litter decomposition for growth yield; the potential activities of the extracellular enzymes cellobiohydrolase (CBH), β-glucosidase (BG), β-xylosidase (BX), and N-acetyl-β-D-glucosaminidase (NAG) for resource acquisition; and ability to grow in drought vs. higher moisture levels for drought stress tolerance. Although, we had hypothesized that evolutionary and physiological trade-offs would elicit negative relationships among traits, we found no supporting evidence for this hypothesis. Across isolates, growth yield, drought stress tolerance, and extracellular enzyme activities were not significantly related to each other. Thus, it is possible that drought-induced shifts in fungal community composition may not necessarily lead to changes in fungal biomass or decomposer ability in this arid grassland.
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Affiliation(s)
- Charlotte J Alster
- Ecology and Evolutionary Biology, University of California Irvine, Irvine, CA, United States
| | - Steven D Allison
- Ecology and Evolutionary Biology, University of California Irvine, Irvine, CA, United States.,Department of Earth System Science, University of California Irvine, Irvine, CA, United States
| | - Sydney I Glassman
- Ecology and Evolutionary Biology, University of California Irvine, Irvine, CA, United States.,Department of Microbiology and Plant Pathology, University of California, Riverside, CA, United States
| | - Adam C Martiny
- Ecology and Evolutionary Biology, University of California Irvine, Irvine, CA, United States.,Department of Earth System Science, University of California Irvine, Irvine, CA, United States
| | - Kathleen K Treseder
- Ecology and Evolutionary Biology, University of California Irvine, Irvine, CA, United States
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30
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Orevi T, Kashtan N. Life in a Droplet: Microbial Ecology in Microscopic Surface Wetness. Front Microbiol 2021; 12:655459. [PMID: 33927707 PMCID: PMC8076497 DOI: 10.3389/fmicb.2021.655459] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 03/19/2021] [Indexed: 12/16/2022] Open
Abstract
While many natural and artificial surfaces may appear dry, they are in fact covered by thin liquid films and microdroplets invisible to the naked eye known as microscopic surface wetness (MSW). Central to the formation and the retention of MSW are the deliquescent properties of hygroscopic salts that prevent complete drying of wet surfaces or that drive the absorption of water until dissolution when the relative humidity is above a salt-specific level. As salts are ubiquitous, MSW occurs in many microbial habitats, such as soil, rocks, plant leaf, and root surfaces, the built environment, and human and animal skin. While key properties of MSW, including very high salinity and segregation into droplets, greatly affect microbial life therein, it has been scarcely studied, and systematic studies are only in their beginnings. Based on recent findings, we propose that the harsh micro-environment that MSW imposes, which is very different from bulk liquid, affects key aspects of bacterial ecology including survival traits, antibiotic response, competition, motility, communication, and exchange of genetic material. Further research is required to uncover the fundamental principles that govern microbial life and ecology in MSW. Such research will require multidisciplinary science cutting across biology, physics, and chemistry, while incorporating approaches from microbiology, genomics, microscopy, and computational modeling. The results of such research will be critical to understand microbial ecology in vast terrestrial habitats, affecting global biogeochemical cycles, as well as plant, animal, and human health.
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Affiliation(s)
- Tomer Orevi
- Department of Plant Pathology and Microbiology, Robert H. Smith Faculty of Agriculture, Food, and Environment, Institute of Environmental Sciences, Hebrew University, Rehovot, Israel
| | - Nadav Kashtan
- Department of Plant Pathology and Microbiology, Robert H. Smith Faculty of Agriculture, Food, and Environment, Institute of Environmental Sciences, Hebrew University, Rehovot, Israel
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31
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Duman M, Mulet M, Altun S, Burcin Saticioglu I, Gomila M, Lalucat J, García-Valdés E. Pseudomonas anatoliensis sp. nov and Pseudomonas iridis sp. nov. isolated from fish. Syst Appl Microbiol 2021; 44:126198. [PMID: 33838437 DOI: 10.1016/j.syapm.2021.126198] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 03/05/2021] [Accepted: 03/09/2021] [Indexed: 11/16/2022]
Abstract
In a study carried out between 2013 and 2018 in fish farms in Turkey, several putative novel species were isolated. The 16S rRNA nucleotide sequences of fourteen strains of Gram-negative rods, which were isolated from asymptomatic and symptomatic rainbow trouts (Onchorhynchus mykiss), placed them under the genus Pseudomonas. The similarity values of the concatenated nucleotide sequences of the rpoD, rpoB, gyrB and 16S rRNA genes clustered these isolates into the P. fluorescens phylogenetic group of species and into the Pseudomonas koreensis subgroup, close to Pseudomonas helmanticensis and Pseudomonas baetica. An isolate of a totally different origin, strain CCUG 67011, clustered with these isolates. Phenotypic characterization, together with the chemotaxonomic data, whole-cell MALDI-TOF MS and fatty acids methyl esters analyses were performed. The DNA G + C content was 58.7 mol% for isolate P9T and 58.8 mol% for isolate P42T. The phylogenomic analysis and whole genome nucleotide sequences of four of these isolates confirmed that the isolates P9T, P25 and P141, represent a novel species for which the name Pseudomonas anatoliensis sp. nov. is proposed, with P9T as the type strain (=CCUG 74755T = CECT 3172T). The isolates P1, P2, P10, P27, P30, P24a, P42T, P117, P139, P152 and CCUG 67011 represent another novel sècies, for which the name Pseudomonas iridis sp. nov. is proposed, with P42T as the type strain (=CCUG 74870T = CECT 3174T).
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Affiliation(s)
- Muhammed Duman
- Department of Aquatic Animal Diseases, Faculty of Veterinary Medicine, Bursa Uludag University, 16059 Bursa, Turkey
| | - Magdalena Mulet
- Microbiologia, Departament de Biologia, Edifici Guillem Colom, Universitat de les Illes Balears, Campus UIB, 07122 Palma de Mallorca, Spain
| | - Soner Altun
- Department of Aquatic Animal Diseases, Faculty of Veterinary Medicine, Bursa Uludag University, 16059 Bursa, Turkey
| | - Izzet Burcin Saticioglu
- Department of Aquatic Animal Diseases, Faculty of Veterinary Medicine, Erciyes University, 38280 Kayseri, Turkey
| | - Margarita Gomila
- Microbiologia, Departament de Biologia, Edifici Guillem Colom, Universitat de les Illes Balears, Campus UIB, 07122 Palma de Mallorca, Spain
| | - Jorge Lalucat
- Microbiologia, Departament de Biologia, Edifici Guillem Colom, Universitat de les Illes Balears, Campus UIB, 07122 Palma de Mallorca, Spain; Institut Mediterrani d'Estudis Avançats (IMEDEA, CSIC-UIB), Campus UIB, 07122 Palma de Mallorca, Spain
| | - Elena García-Valdés
- Microbiologia, Departament de Biologia, Edifici Guillem Colom, Universitat de les Illes Balears, Campus UIB, 07122 Palma de Mallorca, Spain; Institut Mediterrani d'Estudis Avançats (IMEDEA, CSIC-UIB), Campus UIB, 07122 Palma de Mallorca, Spain.
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32
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Gorter FA, Tabares-Mafla C, Kassen R, Schoustra SE. Experimental Evolution of Interference Competition. Front Microbiol 2021; 12:613450. [PMID: 33841345 PMCID: PMC8027309 DOI: 10.3389/fmicb.2021.613450] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 02/28/2021] [Indexed: 01/21/2023] Open
Abstract
The importance of interference competition, where individuals compete through antagonistic traits such as the production of toxins, has long been recognized by ecologists, yet understanding how these types of interactions evolve remains limited. Toxin production is thought to be beneficial when competing with a competitor. Here, we explore if antagonism can evolve by long-term selection of the toxin (pyocin) producing strain Pseudomonas aeruginosa PAO1 in the presence (or absence) of one of three clinical isolates of the same species (Recipient) over ten serial transfers. We find that inhibition decreases in the absence of a recipient. In the presence of a recipient, antagonism evolved to be different depending on the recipient used. Our study shows that the evolution of interference competition by toxins can decrease or increase, experimentally demonstrating the importance of this type of interaction for the evolution of species interactions.
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Affiliation(s)
- Florien A Gorter
- Laboratory of Genetics, Wageningen University & Research, Wageningen, Netherlands.,Department of Environmental Systems Science, Eidgenössische Technische Hochschule, Zurich, Switzerland.,Department of Environmental Microbiology, Eawag, Dübendorf, Switzerland
| | | | - Rees Kassen
- Department of Biology, University of Ottawa, Ottawa, ON, Canada
| | - Sijmen E Schoustra
- Laboratory of Genetics, Wageningen University & Research, Wageningen, Netherlands.,Department of Biology, University of Ottawa, Ottawa, ON, Canada
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33
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Barrett LG, Zala M, Mikaberidze A, Alassimone J, Ahmad M, McDonald BA, Sánchez-Vallet A. Mixed infections alter transmission potential in a fungal plant pathogen. Environ Microbiol 2021; 23:2315-2330. [PMID: 33538383 PMCID: PMC8248022 DOI: 10.1111/1462-2920.15417] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 01/12/2021] [Accepted: 01/28/2021] [Indexed: 01/08/2023]
Abstract
Infections by more than one strain of a pathogen predominate under natural conditions. Mixed infections can have significant, though often unpredictable, consequences for overall virulence, pathogen transmission and evolution. However, effects of mixed infection on disease development in plants often remain unclear and the critical factors that determine the outcome of mixed infections remain unknown. The fungus Zymoseptoria tritici forms genetically diverse infections in wheat fields. Here, for a range of pathogen traits, we experimentally decompose the infection process to determine how the outcomes and consequences of mixed infections are mechanistically realized. Different strains of Z. tritici grow in close proximity and compete in the wheat apoplast, resulting in reductions in growth of individual strains and in pathogen reproduction. We observed different outcomes of competition at different stages of the infection. Overall, more virulent strains had higher competitive ability during host colonization, and less virulent strains had higher transmission potential. We showed that within‐host competition can have a major effect on infection dynamics and pathogen population structure in a pathogen and host genotype‐specific manner. Consequently, mixed infections likely have a major effect on the development of septoria tritici blotch epidemics and the evolution of virulence in Z. tritici.
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Affiliation(s)
- Luke G Barrett
- CSIRO Agriculture and Food, GPO BOX 1700, Canberra, ACT, 2601, Australia
| | - Marcello Zala
- Plant Pathology, Institute of Integrative Biology, ETH Zurich, Universitätstrasse 2, Zurich, 8092, Switzerland
| | - Alexey Mikaberidze
- Plant Pathology, Institute of Integrative Biology, ETH Zurich, Universitätstrasse 2, Zurich, 8092, Switzerland
| | - Julien Alassimone
- Plant Pathology, Institute of Integrative Biology, ETH Zurich, Universitätstrasse 2, Zurich, 8092, Switzerland
| | - Muhammad Ahmad
- Plant Pathology, Institute of Integrative Biology, ETH Zurich, Universitätstrasse 2, Zurich, 8092, Switzerland
| | - Bruce A McDonald
- Plant Pathology, Institute of Integrative Biology, ETH Zurich, Universitätstrasse 2, Zurich, 8092, Switzerland
| | - Andrea Sánchez-Vallet
- Plant Pathology, Institute of Integrative Biology, ETH Zurich, Universitätstrasse 2, Zurich, 8092, Switzerland.,Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM)-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Pozuelo de Alarcón, Madrid, Spain
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34
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Millar JA, Raghavan R. Modulation of Bacterial Fitness and Virulence Through Antisense RNAs. Front Cell Infect Microbiol 2021; 10:596277. [PMID: 33747974 PMCID: PMC7968456 DOI: 10.3389/fcimb.2020.596277] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 12/30/2020] [Indexed: 01/22/2023] Open
Abstract
Regulatory RNAs contribute to gene expression control in bacteria. Antisense RNAs (asRNA) are a class of regulatory RNAs that are transcribed from opposite strands of their target genes. Typically, these untranslated transcripts bind to cognate mRNAs and rapidly regulate gene expression at the post-transcriptional level. In this article, we review asRNAs that modulate bacterial fitness and increase virulence. We chose examples that underscore the variety observed in nature including, plasmid- and chromosome-encoded asRNAs, a riboswitch-regulated asRNA, and asRNAs that require other RNAs or RNA-binding proteins for stability and activity. We explore how asRNAs improve bacterial fitness and virulence by modulating plasmid acquisition and maintenance, regulating transposon mobility, increasing resistance against bacteriophages, controlling flagellar production, and regulating nutrient acquisition. We conclude with a brief discussion on how this knowledge is helping to inform current efforts to develop new therapeutics.
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Affiliation(s)
- Jess A Millar
- Department of Epidemiology, University of Michigan, Ann Arbor, MI, United States.,Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, United States
| | - Rahul Raghavan
- Department of Biology and Center for Life in Extreme Environments, Portland State University, Portland, OR, United States.,Department of Biology, University of Texas at San Antonio, San Antonio, TX, United States
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35
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Droplet printing reveals the importance of micron-scale structure for bacterial ecology. Nat Commun 2021; 12:857. [PMID: 33558498 PMCID: PMC7870943 DOI: 10.1038/s41467-021-20996-w] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 01/06/2021] [Indexed: 12/30/2022] Open
Abstract
Bacteria often live in diverse communities where the spatial arrangement of strains and species is considered critical for their ecology. However, a test of this hypothesis requires manipulation at the fine scales at which spatial structure naturally occurs. Here we develop a droplet-based printing method to arrange bacterial genotypes across a sub-millimetre array. We print strains of the gut bacterium Escherichia coli that naturally compete with one another using protein toxins. Our experiments reveal that toxin-producing strains largely eliminate susceptible non-producers when genotypes are well-mixed. However, printing strains side-by-side creates an ecological refuge where susceptible strains can persist in large numbers. Moving to competitions between toxin producers reveals that spatial structure can make the difference between one strain winning and mutual destruction. Finally, we print different potential barriers between competing strains to understand how ecological refuges form, which shows that cells closest to a toxin producer mop up the toxin and protect their clonemates. Our work provides a method to generate customised bacterial communities with defined spatial distributions, and reveals that micron-scale changes in these distributions can drive major shifts in ecology. The spatial arrangement of bacterial strains and species within microbial communities is considered crucial for their ecology. Here, Krishna Kumar et al. use a droplet-based printing method to arrange different bacterial genotypes across a sub-millimetre array, and show that micron-scale changes in spatial distributions can drive major shifts in ecology.
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36
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Natural bacterial isolates as an inexhaustible source of new bacteriocins. Appl Microbiol Biotechnol 2021; 105:477-492. [PMID: 33394148 DOI: 10.1007/s00253-020-11063-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 12/10/2020] [Accepted: 12/15/2020] [Indexed: 12/12/2022]
Abstract
Microorganisms isolated from various traditionally fermented food products prepared in households without commercial starter cultures are designated as natural isolates. In addition, this term is also used for microorganisms collected from various natural habitats or products (silage, soil, manure, plant and animal material, etc.) that do not contain any commercial starters or bacterial formulations. They are characterized by unique traits that are the result of the selective pressure of environmental conditions, as well as interactions with other organisms. The synthesis of antimicrobial molecules, including bacteriocins, is an evolutionary advantage and an adaptive feature that sets them apart from other microorganisms from a common environment. This review aims to underline the knowledge of bacteriocins produced by natural isolates, with a particular emphasis on the most common location of their genes and operons, plasmids, and the importance of the relationship between the plasmidome and the adaptive potential of the isolate. Applications of bacteriocins, ranging from natural food preservatives to supplements and drugs in pharmacology and medicine, will also be addressed. The latest challenges faced by researchers in isolating new natural isolates with desired characteristics will be discussed, as well as the production of new antimicrobials, nearly one century since the first discovery of colicins in 1925. KEY POINTS: • Natural bacterial isolates harbor unique properties shaped by diverse interactions. • Horizontal gene transfer enables constant engineering of new antimicrobials. • Fermented food products are important source of bacteriocin-producing natural isolates.
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37
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Liao MJ, Miano A, Nguyen CB, Chao L, Hasty J. Survival of the weakest in non-transitive asymmetric interactions among strains of E. coli. Nat Commun 2020; 11:6055. [PMID: 33247128 PMCID: PMC7699631 DOI: 10.1038/s41467-020-19963-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 10/23/2020] [Indexed: 11/22/2022] Open
Abstract
Hierarchical organization in ecology, whereby interactions are nested in a manner that leads to a dominant species, naturally result in the exclusion of all but the dominant competitor. Alternatively, non-hierarchical competitive dynamics, such as cyclical interactions, can sustain biodiversity. Here, we designed a simple microbial community with three strains of E. coli that cyclically interact through (i) the inhibition of protein production, (ii) the digestion of genomic DNA, and (iii) the disruption of the cell membrane. We find that intrinsic differences in these three major mechanisms of bacterial warfare lead to an unbalanced community that is dominated by the weakest strain. We also use a computational model to describe how the relative toxin strengths, initial fractional occupancies, and spatial patterns affect the maintenance of biodiversity. The engineering of active warfare between microbial species establishes a framework for exploration of the underlying principles that drive complex ecological interactions. The maintenance of ecological diversity depends on the strength and direction of competitive interactions, but these interactions are difficult to study in microbial communities. Here the authors use engineered E. coli strains to show that competitively weak strains can persist when pairwise interactions are asymmetrical.
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Affiliation(s)
- Michael J Liao
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA.,BioCircuits Institute, University of California, San Diego, La Jolla, CA, USA
| | - Arianna Miano
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA.,BioCircuits Institute, University of California, San Diego, La Jolla, CA, USA
| | - Chloe B Nguyen
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA
| | - Lin Chao
- Section of Ecology, Behavior and Evolution, Division of Biological Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Jeff Hasty
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA. .,BioCircuits Institute, University of California, San Diego, La Jolla, CA, USA. .,Molecular Biology Section, Division of Biological Science, University of California, San Diego, La Jolla, CA, USA.
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38
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Terán LC, Distefano M, Bellich B, Petrosino S, Bertoncin P, Cescutti P, Sblattero D. Proteomic Studies of the Biofilm Matrix including Outer Membrane Vesicles of Burkholderia multivorans C1576, a Strain of Clinical Importance for Cystic Fibrosis. Microorganisms 2020; 8:E1826. [PMID: 33228110 PMCID: PMC7699398 DOI: 10.3390/microorganisms8111826] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 11/16/2020] [Accepted: 11/17/2020] [Indexed: 12/28/2022] Open
Abstract
Biofilms are aggregates of microbial cells encased in a highly hydrated matrix made up of self-produced extracellular polymeric substances (EPS) which consist of polysaccharides, proteins, nucleic acids, and lipids. While biofilm matrix polysaccharides are unraveled, there is still poor knowledge about the identity and function of matrix-associated proteins. With this work, we performed a comprehensive proteomic approach to disclose the identity of proteins associated with the matrix of biofilm-growing Burkholderia multivorans C1576 reference strain, a cystic fibrosis clinical isolate. Transmission electron microscopy showed that B. multivorans C1576 also releases outer membrane vesicles (OMVs) in the biofilm matrix, as already demonstrated for other Gram-negative species. The proteomic analysis revealed that cytoplasmic and membrane-bound proteins are widely represented in the matrix, while OMVs are highly enriched in outer membrane proteins and siderophores. Our data suggest that cell lysis and OMVs production are the most important sources of proteins for the B. multivorans C1576 biofilm matrix. Of note, some of the identified proteins are lytic enzymes, siderophores, and proteins involved in reactive oxygen species (ROS) scavenging. These proteins might help B. multivorans C1576 in host tissue invasion and defense towards immune system assaults.
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Affiliation(s)
| | | | | | | | | | | | - Daniele Sblattero
- Department of Life Sciences, University of Trieste, 34127 Trieste, Italy; (L.C.T.); (M.D.); (B.B.); (S.P.); (P.B.); (P.C.)
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Stimulation of Bovicin HC5 Production and Selection of Improved Bacteriocin-Producing Streptococcus equinus HC5 Variants. Probiotics Antimicrob Proteins 2020; 13:899-913. [PMID: 32865761 DOI: 10.1007/s12602-020-09703-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Bovicin HC5 is a peptide that has inhibitory activity against various pathogenic microorganisms and food spoilage bacteria. Aiming to improve the productivity of this bacteriocin, we evaluated several potential factors that could stimulate the synthesis of bovicin HC5 and selected variants of Streptococcus equinus (Streptococcus bovis) HC5 with enhanced bacteriocin production by adaptive laboratory evolution (ALE). The highest production of the bacteriocin (1.5-fold) was observed when Strep. equinus HC5 was cultivated with lactic acid (100 mmol/L). For the ALE experiment, Strep. equinus HC5 cells were subjected to acid-shock (pH 3.0 for 2 h) and maintained in continuous culture for approximately 140 generations (40 days) in media with lactic acid (100 mmol/L) and pH-controlled at 5.5 ± 0.2. An adapted variant was selected showing a distinct phenotype (sedimentation, pigmentation) compared with the parental strain. Bacteriocin production increased 2-fold in this adapted Strep. equinus HC5 variant, which appears to be associated with changes in the cell envelope of the adapted variant and enhanced bacteriocin release into the culture media. In addition, the adapted variant showed higher levels of expression of all bovicin HC5 biosynthetic genes compared with the parental strain during the early and late stages of growth. Results presented here indicate that ALE is a promising strategy for selecting strains of lactic acid bacteria with increased production of bacteriocins.
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40
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Hao M, Qiao H, Gao Y, Wang Z, Qiao X, Chen X, Qi H. A mixed culture of bacterial cells enables an economic DNA storage on a large scale. Commun Biol 2020; 3:416. [PMID: 32737399 PMCID: PMC7395121 DOI: 10.1038/s42003-020-01141-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 07/02/2020] [Indexed: 11/25/2022] Open
Abstract
DNA emerged as a novel potential material for mass data storage, offering the possibility to cheaply solve a great data storage problem. Large oligonucleotide pools demonstrated high potential of large-scale data storage in test tube, meanwhile, living cell with high fidelity in information replication. Here we show a mixed culture of bacterial cells carrying a large oligo pool that was assembled in a high-copy-number plasmid was presented as a stable material for large-scale data storage. The underlying principle was explored by deep bioinformatic analysis. Although homology assembly showed sequence context dependent bias, the large oligonucleotide pools in the mixed culture were constant over multiple successive passages. Finally, over ten thousand distinct oligos encompassing 2304 Kbps encoding 445 KB digital data, were stored in cells, the largest storage in living cells reported so far and present a previously unreported approach for bridging the gap between in vitro and in vivo systems. Hao, Qiao, Gao et al. show that over ten thousand oligonucleotides encoding 445 KB of digital data can be stored in cultured bacterial cells. Data storage in living cells increases the information storage capacity while enabling its economical propagation.
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Affiliation(s)
- Min Hao
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China
| | - Hongyan Qiao
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China
| | - Yanmin Gao
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China
| | - Zhaoguan Wang
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China
| | - Xin Qiao
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China
| | - Xin Chen
- Center for Applied Mathematics, Tianjin University, Tianjin, China
| | - Hao Qi
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, China. .,Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China.
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Gorter FA, Manhart M, Ackermann M. Understanding the evolution of interspecies interactions in microbial communities. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190256. [PMID: 32200743 DOI: 10.1098/rstb.2019.0256] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Microbial communities are complex multi-species assemblages that are characterized by a multitude of interspecies interactions, which can range from mutualism to competition. The overall sign and strength of interspecies interactions have important consequences for emergent community-level properties such as productivity and stability. It is not well understood how interspecies interactions change over evolutionary timescales. Here, we review the empirical evidence that evolution is an important driver of microbial community properties and dynamics on timescales that have traditionally been regarded as purely ecological. Next, we briefly discuss different modelling approaches to study evolution of communities, emphasizing the similarities and differences between evolutionary and ecological perspectives. We then propose a simple conceptual model for the evolution of interspecies interactions in communities. Specifically, we propose that to understand the evolution of interspecies interactions, it is important to distinguish between direct and indirect fitness effects of a mutation. We predict that in well-mixed environments, traits will be selected exclusively for their direct fitness effects, while in spatially structured environments, traits may also be selected for their indirect fitness effects. Selection of indirectly beneficial traits should result in an increase in interaction strength over time, while selection of directly beneficial traits should not have such a systematic effect. We tested our intuitions using a simple quantitative model and found support for our hypotheses. The next step will be to test these hypotheses experimentally and provide input for a more refined version of the model in turn, thus closing the scientific cycle of models and experiments. This article is part of the theme issue 'Conceptual challenges in microbial community ecology'.
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Affiliation(s)
- Florien A Gorter
- Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, ETH Zürich, Zürich, Switzerland.,Department of Environmental Microbiology, Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf, Switzerland
| | - Michael Manhart
- Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, ETH Zürich, Zürich, Switzerland.,Institute of Integrative Biology, Department of Environmental Systems Science, ETH Zürich, Zürich, Switzerland.,Department of Environmental Microbiology, Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf, Switzerland
| | - Martin Ackermann
- Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, ETH Zürich, Zürich, Switzerland.,Department of Environmental Microbiology, Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf, Switzerland
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42
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Ratzke C, Barrere J, Gore J. Strength of species interactions determines biodiversity and stability in microbial communities. Nat Ecol Evol 2020; 4:376-383. [PMID: 32042124 DOI: 10.1101/671008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 01/06/2020] [Indexed: 05/18/2023]
Abstract
Organisms-especially microbes-tend to live together in ecosystems. While some of these ecosystems are very biodiverse, others are not, and while some are very stable over time, others undergo strong temporal fluctuations. Despite a long history of research and a plethora of data, it is not fully understood what determines the biodiversity and stability of ecosystems. Theory and experiments suggest a connection between species interaction, biodiversity and the stability of ecosystems, where an increase in ecosystem stability with biodiversity could be observed in several cases. However, what causes these connections remains unclear. Here, we show in microbial ecosystems in the laboratory that the concentrations of available nutrients can set the strength of interactions between bacteria. High nutrient concentrations allowed the bacteria to strongly alter the chemical environment, causing on average more negative interactions between species. These stronger interactions excluded more species from the community, resulting in a loss of biodiversity. At the same time, the stronger interactions also decreased the stability of the microbial communities, providing a mechanistic link between species interaction, biodiversity and stability in microbial ecosystems.
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Affiliation(s)
- Christoph Ratzke
- Physics of Living Systems, Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA.
| | - Julien Barrere
- Physics of Living Systems, Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, USA
| | - Jeff Gore
- Physics of Living Systems, Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA.
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43
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Ratzke C, Barrere J, Gore J. Strength of species interactions determines biodiversity and stability in microbial communities. Nat Ecol Evol 2020; 4:376-383. [DOI: 10.1038/s41559-020-1099-4] [Citation(s) in RCA: 151] [Impact Index Per Article: 37.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 01/06/2020] [Indexed: 12/18/2022]
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Mullis MM, Rambo IM, Baker BJ, Reese BK. Diversity, Ecology, and Prevalence of Antimicrobials in Nature. Front Microbiol 2019; 10:2518. [PMID: 31803148 PMCID: PMC6869823 DOI: 10.3389/fmicb.2019.02518] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 10/18/2019] [Indexed: 12/15/2022] Open
Abstract
Microorganisms possess a variety of survival mechanisms, including the production of antimicrobials that function to kill and/or inhibit the growth of competing microorganisms. Studies of antimicrobial production have largely been driven by the medical community in response to the rise in antibiotic-resistant microorganisms and have involved isolated pure cultures under artificial laboratory conditions neglecting the important ecological roles of these compounds. The search for new natural products has extended to biofilms, soil, oceans, coral reefs, and shallow coastal sediments; however, the marine deep subsurface biosphere may be an untapped repository for novel antimicrobial discovery. Uniquely, prokaryotic survival in energy-limited extreme environments force microbial populations to either adapt their metabolism to outcompete or produce novel antimicrobials that inhibit competition. For example, subsurface sediments could yield novel antimicrobial genes, while at the same time answering important ecological questions about the microbial community.
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Affiliation(s)
- Megan M Mullis
- Department of Life Sciences, Texas A&M University Corpus Christi, Corpus Christi, TX, United States
| | - Ian M Rambo
- Department of Marine Science, University of Texas Marine Science Institute, Port Aransas, TX, United States
| | - Brett J Baker
- Department of Marine Science, University of Texas Marine Science Institute, Port Aransas, TX, United States
| | - Brandi Kiel Reese
- Department of Life Sciences, Texas A&M University Corpus Christi, Corpus Christi, TX, United States
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45
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Shyntum DY, Nkomo NP, Shingange NL, Gricia AR, Bellieny-Rabelo D, Moleleki LN. The Impact of Type VI Secretion System, Bacteriocins and Antibiotics on Bacterial Competition of Pectobacterium carotovorum subsp. brasiliense and the Regulation of Carbapenem Biosynthesis by Iron and the Ferric-Uptake Regulator. Front Microbiol 2019; 10:2379. [PMID: 31681235 PMCID: PMC6813493 DOI: 10.3389/fmicb.2019.02379] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 09/30/2019] [Indexed: 12/17/2022] Open
Abstract
The complexity of plant microbial communities provides a rich model for investigating biochemical and regulatory strategies involved in interbacterial competition. Within these niches, the soft rot Enterobacteriaceae (SRE) represents an emerging group of plant-pathogens causing soft rot/blackleg diseases resulting in economic losses worldwide in a variety of crops. A preliminary screening using next-generation sequencing of 16S rRNA comparatively analyzing healthy and diseased potato tubers, identified several taxa from Proteobacteria to Firmicutes as potential potato endophytes/plant pathogens. Subsequent to this, a range of molecular and computational techniques were used to determine the contribution of antimicrobial factors such as bacteriocins, carbapenem and type VI secretion system (T6SS), found in an aggressive SRE (Pectobacterium carotovorum subsp. brasiliense strain PBR1692 - Pcb1692) against these endophytes/plant pathogens. The results showed growth inhibition of several Proteobacteria by Pcb1692 depends either on carbapenem or pyocin production. Whereas for targeted Firmicutes, only the Pcb1692 pyocin seems to play a role in growth inhibition. Furthermore, production of carbapenem by Pcb1692 was observably dependent on the presence of environmental iron and oxygen. Additionally, upon deletion of fur, slyA and expI regulators, carbapenem production ceased, implying a complex regulatory mechanism involving these three genes. Finally, the results demonstrated that although T6SS confers no relevant advantage during in vitro competition, a significant attenuation in competition by the mutant strain lacking a functional T6SS was observed in planta. IMPORTANCE Soft rot Enterobacteriaceae (SRE) represents important phytopathogens causing soft rot/blackleg diseases in a variety of crops leading to huge economic losses worldwide. These pathogens have been isolated alongside other bacteria from different environments such as potato tubers, stems, roots and from the soil. In these environments, SREs coexist with other bacteria where they have to compete for scarce nutrients and other resources. In this report, we show that Pectobacterium carotovorum subsp. brasiliense strain PBR1692 - Pcb1692, which represents one of the SREs, inhibits growth of several different bacteria by producing different antimicrobial compounds. These antimicrobial compounds can be secreted inside or outside the plant host, allowing Pcb1692 to effectively colonize different types of ecological niches. By analyzing the genome sequences of several SREs, we show that other SREs likely deploy similar antimicrobials to target other bacteria.
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Affiliation(s)
- Divine Yufetar Shyntum
- Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
- Forestry, Agriculture and Biotechnology Institute, University of Pretoria, Pretoria, South Africa
| | - Ntombikayise Precious Nkomo
- Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
- Forestry, Agriculture and Biotechnology Institute, University of Pretoria, Pretoria, South Africa
| | - Ntwanano Luann Shingange
- Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
| | - Alessandro Rino Gricia
- Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
- Forestry, Agriculture and Biotechnology Institute, University of Pretoria, Pretoria, South Africa
| | - Daniel Bellieny-Rabelo
- Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
- Forestry, Agriculture and Biotechnology Institute, University of Pretoria, Pretoria, South Africa
| | - Lucy Novungayo Moleleki
- Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
- Forestry, Agriculture and Biotechnology Institute, University of Pretoria, Pretoria, South Africa
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46
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Redero M, López-Causapé C, Aznar J, Oliver A, Blázquez J, Prieto AI. Susceptibility to R-pyocins of Pseudomonas aeruginosa clinical isolates from cystic fibrosis patients. J Antimicrob Chemother 2019; 73:2770-2776. [PMID: 30052973 DOI: 10.1093/jac/dky261] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 06/08/2018] [Indexed: 12/15/2022] Open
Abstract
Background The appearance and dissemination of MDR among pathogenic bacteria has forced the search for new antimicrobials. Bacteriocins have been proposed as potential alternatives for the treatment of infections due to multiresistant strains. Objectives To analyse the activity of R-pyocins against clinical isolates of Pseudomonas aeruginosa from patients with cystic fibrosis and other sources and evaluate them as a potential adjuvant or alternative to the current antibiotic treatment. Methods The activity of R-pyocins against 150 strains of P. aeruginosa isolated from patients with cystic fibrosis or bacteraemia was studied through spot assay. Interactions between R-pyocins and antipseudomonal agents were quantitatively studied by the chequerboard method. Results The proportion of P. aeruginosa isolates susceptible to R-pyocins was found to be higher in cystic fibrosis isolates compared with bacteraemia isolates (79.41% versus 50%). Moreover, no interactions were found between common antipseudomonal agents and R-pyocin susceptibility, except for the ST175 high-risk clone. Conclusions Our results highlight the possibility of using R-pyocins as therapeutic agents, alone or as adjuvants, against P. aeruginosa in cystic fibrosis.
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Affiliation(s)
- Mar Redero
- Instituto de Biomedicina de Sevilla (IBIS), Avda. Manuel Siurot s/n, Seville, Spain.,Unidad de Enfermedades Infecciosas, Microbiología y Medicina Preventiva, Hospital Universitario Virgen del Rocío, Seville, Spain.,Universidad de Sevilla, Seville, Spain
| | - Carla López-Causapé
- Servicio de Microbiología y Unidad de Investigación, Hospital Universitario Son Espases, Palma de Mallorca, Spain
| | - Javier Aznar
- Instituto de Biomedicina de Sevilla (IBIS), Avda. Manuel Siurot s/n, Seville, Spain.,Unidad de Enfermedades Infecciosas, Microbiología y Medicina Preventiva, Hospital Universitario Virgen del Rocío, Seville, Spain.,Universidad de Sevilla, Seville, Spain
| | - Antonio Oliver
- Servicio de Microbiología y Unidad de Investigación, Hospital Universitario Son Espases, Palma de Mallorca, Spain
| | - Jesús Blázquez
- Instituto de Biomedicina de Sevilla (IBIS), Avda. Manuel Siurot s/n, Seville, Spain.,Unidad de Enfermedades Infecciosas, Microbiología y Medicina Preventiva, Hospital Universitario Virgen del Rocío, Seville, Spain.,Centro Nacional de Biotecnología (CNB), Madrid, Spain
| | - Ana I Prieto
- Instituto de Biomedicina de Sevilla (IBIS), Avda. Manuel Siurot s/n, Seville, Spain.,Unidad de Enfermedades Infecciosas, Microbiología y Medicina Preventiva, Hospital Universitario Virgen del Rocío, Seville, Spain
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47
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Essarioui A, LeBlanc N, Otto-Hanson L, Schlatter DC, Kistler HC, Kinkel LL. Inhibitory and nutrient use phenotypes among coexisting Fusarium and Streptomyces populations suggest local coevolutionary interactions in soil. Environ Microbiol 2019; 22:976-985. [PMID: 31424591 DOI: 10.1111/1462-2920.14782] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 06/22/2019] [Accepted: 08/14/2019] [Indexed: 11/29/2022]
Abstract
Bacteria and fungi are key components of virtually all natural habitats, yet the significance of fungal-bacterial inhibitory interactions for the ecological and evolutionary dynamics of specific bacterial and fungal populations in natural habitats have been overlooked. More specifically, despite the broad consensus that antibiotics play a key role in providing a fitness advantage to competing microbes, the significance of antibiotic production in mediating cross-kingdom coevolutionary interactions has received relatively little attention. Here, we characterize reciprocal inhibition among Streptomyces and Fusarium populations from prairie soil, and explore antibiotic inhibition in relation to niche overlap among sympatric and allopatric populations. We found evidence for local adaptation between Fusarium and Streptomyces populations as indicated by significantly greater inhibition among sympatric than allopatric populations. Additionally, for both taxa, there was a significant positive correlation between the strength of inhibition against the other taxon and the intensity of resource competition from that taxon among sympatric but not allopatric populations. These data suggest that coevolutionary antagonistic interactions between Fusarium and Streptomyces are driven by resource competition, and support the hypothesis that antibiotics act as weapons in mediating bacterial-fungal interactions in soil.
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Affiliation(s)
- Adil Essarioui
- National Institute of Agronomic Research, Regional Center of Errachidia, Errachidia, Morocco.,Department of plant pathology, University of Minnesota, Minneapolis, MN, USA
| | - Nicholas LeBlanc
- Department of plant pathology, University of Minnesota, Minneapolis, MN, USA
| | - Lindsey Otto-Hanson
- Department of plant pathology, University of Minnesota, Minneapolis, MN, USA
| | | | - Harold Corby Kistler
- USDA-ARS Cereal Disease Laboratory, Department of Plant Pathology, University of Minnesota, Minneapolis, MN, USA
| | - Linda L Kinkel
- Department of plant pathology, University of Minnesota, Minneapolis, MN, USA
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48
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Westhoff S, Otto SB, Swinkels A, Bode B, van Wezel GP, Rozen DE. Spatial structure increases the benefits of antibiotic production in Streptomyces. Evolution 2019; 74:179-187. [PMID: 31393002 PMCID: PMC6973283 DOI: 10.1111/evo.13817] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Revised: 06/28/2019] [Accepted: 07/02/2019] [Indexed: 12/17/2022]
Abstract
Bacteria in the soil compete for limited resources. One of the ways they might do this is by producing antibiotics, but the metabolic costs of antibiotics and their low concentrations have caused uncertainty about the ecological role of these products for the bacteria that produce them. Here, we examine the benefits of streptomycin production by the filamentous bacterium Streptomyces griseus. We first provide evidence that streptomycin production enables S. griseus to kill and invade the susceptible species, S. coelicolor, but not a streptomycin‐resistant mutant of this species. Next, we show that the benefits of streptomycin production are density dependent, because production scales positively with cell number, and frequency dependent, with a threshold of invasion of S. griseus at around 1%. Finally, using serial transfer experiments where spatial structure is either maintained or destroyed, we show that spatial structure reduces the threshold frequency of invasion by more than 100‐fold, indicating that antibiotic production can permit invasion from extreme rarity. Our results show that streptomycin is both an offensive and defensive weapon that facilitates invasion into occupied habitats and also protects against invasion by competitors. They also indicate that the benefits of antibiotic production rely on ecological interactions occurring at small local scales.
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Affiliation(s)
- Sanne Westhoff
- Institute of Biology, Leiden University, Sylviusweg 72, 2333, BE, Leiden, The Netherlands
| | - Simon B Otto
- Institute of Biology, Leiden University, Sylviusweg 72, 2333, BE, Leiden, The Netherlands
| | - Aram Swinkels
- Institute of Biology, Leiden University, Sylviusweg 72, 2333, BE, Leiden, The Netherlands
| | - Bo Bode
- Institute of Biology, Leiden University, Sylviusweg 72, 2333, BE, Leiden, The Netherlands
| | - Gilles P van Wezel
- Institute of Biology, Leiden University, Sylviusweg 72, 2333, BE, Leiden, The Netherlands
| | - Daniel E Rozen
- Institute of Biology, Leiden University, Sylviusweg 72, 2333, BE, Leiden, The Netherlands
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49
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Choyam S, Srivastava AK, Shin JH, Kammara R. Ocins for Food Safety. Front Microbiol 2019; 10:1736. [PMID: 31428063 PMCID: PMC6687839 DOI: 10.3389/fmicb.2019.01736] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 07/15/2019] [Indexed: 02/06/2023] Open
Abstract
The food industry produces highly perishable products. Food spoilage represents a severe problem for food manufacturers. Therefore, it is important to identify effective preservation solutions to prevent food spoilage. Ocins (e.g., bacteriocins, lactocins, and enterocins) are antibacterial proteins synthesized by bacteria that destroy or suppress the growth of related or unrelated bacterial strains. Ocins represent a promising strategy for food preservation, because of their antagonist effects toward food spoilage microorganisms, high potency, and low toxicity. Additionally, they can be bioengineered. The most common and commercially available ocins are nisin, plantaracin, sakacin P, and pediocin. Several ocins have been characterized and studied biochemically and genetically; however, their structure-function relationship, biosynthesis, and mechanism of action are not understood. This narrative review focuses primarily on ocins and their relevance to the food industry to help prevent food spoilage. In particular, the applications and limitations of ocins in the food industry are highlighted.
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Affiliation(s)
- Shilja Choyam
- Affiliated to AcSIR for Ph.D. Thesis, CSIR-CFTRI, Mysuru, India
- Department of Protein Chemistry and Technology, CSIR-CFTRI, Mysuru, India
| | | | - Jae-Ho Shin
- School of Applied Biosciences, Kyungpook National University, Daegu, South Korea
| | - Rajagopal Kammara
- Affiliated to AcSIR for Ph.D. Thesis, CSIR-CFTRI, Mysuru, India
- Department of Protein Chemistry and Technology, CSIR-CFTRI, Mysuru, India
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Colicin Z, a structurally and functionally novel colicin type that selectively kills enteroinvasive Escherichia coli and Shigella strains. Sci Rep 2019; 9:11127. [PMID: 31366939 PMCID: PMC6668396 DOI: 10.1038/s41598-019-47488-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 07/16/2019] [Indexed: 01/14/2023] Open
Abstract
Colicin production in Escherichia coli (E. coli) strains represents an important trait with regard to microbial survival and competition in the complex intestinal environment. A novel colicin type, colicin Z (26.3 kDa), was described as a product of an original producer, extraintestinal E. coli B1356 strain, isolated from the anorectal abscess of a 17 years-old man. The 4,007 bp plasmid (pColZ) was completely sequenced and colicin Z activity (cza) and colicin Z immunity (czi) genes were identified. The cza and czi genes are transcribed in opposite directions and encode for 237 and 151 amino acid-long proteins, respectively. Colicin Z shows a narrow inhibitory spectrum, being active only against enteroinvasive E. coli (EIEC) and Shigella strains via CjrC receptor recognition and CjrB- and ExbB-, ExbD-mediated colicin translocation. All tested EIEC and Shigella strains isolated between the years 1958–2010 were sensitive to colicin Z. The lethal effect of colicin Z was found to be directed against cell wall peptidoglycan (PG) resulting in PG degradation, as revealed by experiments with Remazol Brilliant Blue-stained purified peptidoglycans and with MALDI-TOF MS analyses of treated PG. Colicin Z represents a new class of colicins that is structurally and functionally distinct from previously studied colicin types.
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