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Hesse E, Luján AM, O'Brien S, Newbury A, McAvoy T, Soria Pascual J, Bayer F, Hodgson DJ, Buckling A. Parallel ecological and evolutionary responses to selection in a natural bacterial community. Proc Natl Acad Sci U S A 2024; 121:e2403577121. [PMID: 39190353 DOI: 10.1073/pnas.2403577121] [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: 02/20/2024] [Accepted: 07/09/2024] [Indexed: 08/28/2024] Open
Abstract
Evolution can occur over ecological timescales, suggesting a potentially important role for rapid evolution in shaping community trait distributions. However, evidence of concordant eco-evolutionary dynamics often comes from in vitro studies of highly simplified communities, and measures of ecological and evolutionary dynamics are rarely directly comparable. Here, we quantified how ecological species sorting and rapid evolution simultaneously shape community trait distributions by tracking within- and between-species changes in a key trait in a complex bacterial community. We focused on the production of siderophores; bacteria use these costly secreted metabolites to scavenge poorly soluble iron and to detoxify environments polluted with toxic nonferrous metals. We found that responses to copper-imposed selection within and between species were ultimately the same-intermediate siderophore levels were favored-and occurred over similar timescales. Despite being a social trait, this level of siderophore production was selected regardless of whether species evolved in isolation or in a community context. Our study suggests that evolutionary selection can play a pivotal role in shaping community trait distributions within natural, highly complex, bacterial communities. Furthermore, trait evolution may not always be qualitatively affected by interactions with other community members.
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Affiliation(s)
- Elze Hesse
- Centre for Ecology and Conservation & Environment and Sustainability Institute, Faculty of Environment, Science and Economy, University of Exeter, Cornwall TR10 9FE, United Kingdom
| | - Adela M Luján
- Centre for Ecology and Conservation & Environment and Sustainability Institute, Faculty of Environment, Science and Economy, University of Exeter, Cornwall TR10 9FE, United Kingdom
- Centro de Investigación y Desarrollo en Inmunología y Enfermedades Infecciosas, Consejo Nacional de Investigaciones Científicas y Técnicas/Universidad Católica de Córdoba, Córdoba X5016DHK, Argentina
- Facultad de Ciencias de la Salud, Universidad Católica de Córdoba (UCC), Córdoba X5004ASK, Argentina
| | - Siobhan O'Brien
- Centre for Ecology and Conservation & Environment and Sustainability Institute, Faculty of Environment, Science and Economy, University of Exeter, Cornwall TR10 9FE, United Kingdom
| | - Arthur Newbury
- Centre for Ecology and Conservation & Environment and Sustainability Institute, Faculty of Environment, Science and Economy, University of Exeter, Cornwall TR10 9FE, United Kingdom
| | - Terence McAvoy
- Centre for Ecology and Conservation & Environment and Sustainability Institute, Faculty of Environment, Science and Economy, University of Exeter, Cornwall TR10 9FE, United Kingdom
| | - Jesica Soria Pascual
- Centre for Ecology and Conservation & Environment and Sustainability Institute, Faculty of Environment, Science and Economy, University of Exeter, Cornwall TR10 9FE, United Kingdom
| | - Florian Bayer
- Centre for Ecology and Conservation & Environment and Sustainability Institute, Faculty of Environment, Science and Economy, University of Exeter, Cornwall TR10 9FE, United Kingdom
| | - David J Hodgson
- Centre for Ecology and Conservation, Faculty of Environment, Science and Economy, University of Exeter, Cornwall TR10 9FE, United Kingdom
| | - Angus Buckling
- Centre for Ecology and Conservation & Environment and Sustainability Institute, Faculty of Environment, Science and Economy, University of Exeter, Cornwall TR10 9FE, United Kingdom
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2
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Seručnik M, Dogsa I, Zadravec LJ, Mandic-Mulec I, Žnidaršič-Plazl P. Development of a Microbioreactor for Bacillus subtilis Biofilm Cultivation. MICROMACHINES 2024; 15:1037. [PMID: 39203688 PMCID: PMC11356062 DOI: 10.3390/mi15081037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 08/08/2024] [Accepted: 08/09/2024] [Indexed: 09/03/2024]
Abstract
To improve our understanding of Bacillus subtilis growth and biofilm formation under different environmental conditions, two versions of a microfluidic reactor with two channels separated by a polydimethylsiloxane (PDMS) membrane were developed. The gas phase was introduced into the channel above the membrane, and oxygen transfer from the gas phase through the membrane was assessed by measuring the dissolved oxygen concentration in the liquid phase using a miniaturized optical sensor and oxygen-sensitive nanoparticles. B. subtilis biofilm formation was monitored in the growth channels of the microbioreactors, which were designed in two shapes: one with circular extensions and one without. The volumes of these microbioreactors were (17 ± 4) μL for the reactors without extensions and (28 ± 4) μL for those with extensions. The effect of microbioreactor geometry and aeration on B. subtilis biofilm growth was evaluated by digital image analysis. In both microbioreactor geometries, stable B. subtilis biofilm formation was achieved after 72 h of incubation at a growth medium flow rate of 1 μL/min. The amount of oxygen significantly influenced biofilm formation. When the culture was cultivated with a continuous air supply, biofilm surface coverage and biomass concentration were higher than in cultivations without aeration or with a 100% oxygen supply. The channel geometry with circular extensions did not lead to a higher total biomass in the microbioreactor compared to the geometry without extensions.
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Affiliation(s)
- Mojca Seručnik
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI-1000 Ljubljana, Slovenia; (M.S.); (L.J.Z.)
| | - Iztok Dogsa
- Biotechnical Faculty, University of Ljubljana, Večna pot 111, SI-1000 Ljubljana, Slovenia; (I.D.); (I.M.-M.)
| | - Lan Julij Zadravec
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI-1000 Ljubljana, Slovenia; (M.S.); (L.J.Z.)
| | - Ines Mandic-Mulec
- Biotechnical Faculty, University of Ljubljana, Večna pot 111, SI-1000 Ljubljana, Slovenia; (I.D.); (I.M.-M.)
- Chair of Micro Process Engineering and Technology—COMPETE, University of Ljubljana, Večna pot 113, SI-1000 Ljubljana, Slovenia
| | - Polona Žnidaršič-Plazl
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI-1000 Ljubljana, Slovenia; (M.S.); (L.J.Z.)
- Chair of Micro Process Engineering and Technology—COMPETE, University of Ljubljana, Večna pot 113, SI-1000 Ljubljana, Slovenia
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3
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Richter A, Blei F, Hu G, Schwitalla JW, Lozano-Andrade CN, Xie J, Jarmusch SA, Wibowo M, Kjeldgaard B, Surabhi S, Xu X, Jautzus T, Phippen CBW, Tyc O, Arentshorst M, Wang Y, Garbeva P, Larsen TO, Ram AFJ, van den Hondel CAM, Maróti G, Kovács ÁT. Enhanced surface colonisation and competition during bacterial adaptation to a fungus. Nat Commun 2024; 15:4486. [PMID: 38802389 PMCID: PMC11130161 DOI: 10.1038/s41467-024-48812-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 05/13/2024] [Indexed: 05/29/2024] Open
Abstract
Bacterial-fungal interactions influence microbial community performance of most ecosystems and elicit specific microbial behaviours, including stimulating specialised metabolite production. Here, we use a co-culture experimental evolution approach to investigate bacterial adaptation to the presence of a fungus, using a simple model of bacterial-fungal interactions encompassing the bacterium Bacillus subtilis and the fungus Aspergillus niger. We find in one evolving population that B. subtilis was selected for enhanced production of the lipopeptide surfactin and accelerated surface spreading ability, leading to inhibition of fungal expansion and acidification of the environment. These phenotypes were explained by specific mutations in the DegS-DegU two-component system. In the presence of surfactin, fungal hyphae exhibited bulging cells with delocalised secretory vesicles possibly provoking an RlmA-dependent cell wall stress. Thus, our results indicate that the presence of the fungus selects for increased surfactin production, which inhibits fungal growth and facilitates the competitive success of the bacterium.
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Affiliation(s)
- Anne Richter
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, Kgs Lyngby, Denmark
- Terrestrial Biofilms Group, Institute of Microbiology, Friedrich Schiller University Jena, Jena, Germany
| | - Felix Blei
- Terrestrial Biofilms Group, Institute of Microbiology, Friedrich Schiller University Jena, Jena, Germany
- Department Pharmaceutical Microbiology, Hans-Knöll-Institute, Friedrich-Schiller-Universität, Jena, Germany
| | - Guohai Hu
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, Kgs Lyngby, Denmark
- China National GeneBank, BGI-Shenzhen, Shenzhen, China
- BGI-Shenzhen, Shenzhen, China
- Shenzhen Key Laboratory of Environmental Microbial Genomics and Application, BGI-Shenzhen, Shenzhen, China
| | - Jan W Schwitalla
- Terrestrial Biofilms Group, Institute of Microbiology, Friedrich Schiller University Jena, Jena, Germany
| | - Carlos N Lozano-Andrade
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, Kgs Lyngby, Denmark
| | - Jiyu Xie
- Institute of Biology, Leiden University, Leiden, The Netherlands
| | - Scott A Jarmusch
- Natural Product Discovery Group, DTU Bioengineering, Technical University of Denmark, Kgs Lyngby, Denmark
| | - Mario Wibowo
- Natural Product Discovery Group, DTU Bioengineering, Technical University of Denmark, Kgs Lyngby, Denmark
- Singapore Institute of Food and Biotechnology Innovation (SIFBI), Agency for Science, Technology and Research, Singapore, Republic of Singapore
| | - Bodil Kjeldgaard
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, Kgs Lyngby, Denmark
| | - Surabhi Surabhi
- Terrestrial Biofilms Group, Institute of Microbiology, Friedrich Schiller University Jena, Jena, Germany
| | - Xinming Xu
- Institute of Biology, Leiden University, Leiden, The Netherlands
| | - Theresa Jautzus
- Terrestrial Biofilms Group, Institute of Microbiology, Friedrich Schiller University Jena, Jena, Germany
| | - Christopher B W Phippen
- Natural Product Discovery Group, DTU Bioengineering, Technical University of Denmark, Kgs Lyngby, Denmark
| | - Olaf Tyc
- Netherlands Institute of Ecology, Wageningen, The Netherlands
- Department of Internal Medicine I, Goethe University Hospital, Frankfurt, Germany
| | - Mark Arentshorst
- Institute of Biology, Leiden University, Leiden, The Netherlands
| | - Yue Wang
- China National GeneBank, BGI-Shenzhen, Shenzhen, China
- BGI-Shenzhen, Shenzhen, China
| | - Paolina Garbeva
- Netherlands Institute of Ecology, Wageningen, The Netherlands
| | - Thomas Ostenfeld Larsen
- Natural Product Discovery Group, DTU Bioengineering, Technical University of Denmark, Kgs Lyngby, Denmark
| | - Arthur F J Ram
- Institute of Biology, Leiden University, Leiden, The Netherlands
| | | | - Gergely Maróti
- Institute of Plant Biology, Biological Research Centre, Eötvös Loránd Research Network (ELKH), Szeged, Hungary
| | - Ákos T Kovács
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, Kgs Lyngby, Denmark.
- Terrestrial Biofilms Group, Institute of Microbiology, Friedrich Schiller University Jena, Jena, Germany.
- Institute of Biology, Leiden University, Leiden, The Netherlands.
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4
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Hu G, Wang Y, Liu X, Strube ML, Wang B, Kovács ÁT. Species and condition shape the mutational spectrum in experimentally evolved biofilms. mSystems 2023; 8:e0054823. [PMID: 37768063 PMCID: PMC10654089 DOI: 10.1128/msystems.00548-23] [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: 05/27/2023] [Accepted: 08/11/2023] [Indexed: 09/29/2023] Open
Abstract
IMPORTANCE Biofilm formation is a vital factor for the survival and adaptation of bacteria in diverse environmental niches. Experimental evolution combined with the advancement of whole-population genome sequencing provides us a powerful tool to understand the genomic dynamic of evolutionary adaptation to different environments, such as during biofilm development. Previous studies described the genetic and phenotypic changes of selected clones from experimentally evolved Bacillus thuringiensis and Bacillus subtilis that were adapted under abiotic and biotic biofilm conditions. However, the full understanding of the dynamic evolutionary landscapes was lacking. Furthermore, the differences and similarities of adaptive mechanisms in B. thuringiensis and B. subtilis were not identified. To overcome these limitations, we performed longitudinal whole-population genome sequencing to study the underlying genetic dynamics at high resolution. Our study provides the first comprehensive mutational landscape of two bacterial species' biofilms that is adapted to an abiotic and biotic surface.
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Affiliation(s)
- Guohai Hu
- China National GeneBank, BGI, Shenzhen, China
- BGI Research, Shenzhen, China
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, Lyngby, Denmark
| | - Yue Wang
- China National GeneBank, BGI, Shenzhen, China
- BGI Research, Shenzhen, China
- BGI Research, Beijing, China
| | - Xin Liu
- China National GeneBank, BGI, Shenzhen, China
- BGI Research, Shenzhen, China
- BGI Research, Beijing, China
| | - Mikael Lenz Strube
- Bacterial Ecophysiology and Biotechnology Group, DTU Bioengineering, Technical University of Denmark, Lyngby, Denmark
| | - Bo Wang
- China National GeneBank, BGI, Shenzhen, China
- BGI Research, Shenzhen, China
- Shenzhen Key Laboratory of Environmental Microbial Genomics and Application, BGI Research, Shenzhen, China
| | - Ákos T. Kovács
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, Lyngby, Denmark
- Institute of Biology, Leiden University, Leiden, The Netherlands
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5
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Hu G, Wang Y, Blake C, Nordgaard M, Liu X, Wang B, Kovács ÁT. Parallel genetic adaptation of Bacillus subtilis to different plant species. Microb Genom 2023; 9:mgen001064. [PMID: 37466402 PMCID: PMC10438812 DOI: 10.1099/mgen.0.001064] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 06/16/2023] [Indexed: 07/20/2023] Open
Abstract
Plant growth-promoting rhizobacteria benefit plants by stimulating their growth or protecting them against phytopathogens. Rhizobacteria must colonize and persist on plant roots to exert their benefits. However, little is known regarding the processes by which rhizobacteria adapt to different plant species, or behave under alternating host plant regimes. Here, we used experimental evolution and whole-population whole-genome sequencing to analyse how Bacillus subtilis evolves on Arabidopsis thaliana and tomato seedlings, and under an alternating host plant regime, in a static hydroponic setup. We observed parallel evolution across multiple levels of biological organization in all conditions, which was greatest for the two heterogeneous, multi-resource, spatially structured environments at the genetic level. Species-specific adaptation at the genetic level was also observed, possibly caused by the selection stress imposed by different host plants. Furthermore, a trade-off between motility and biofilm development was supported by mutational changes in motility- and biofilm-related genes. Finally, we identified several condition-specific and common targeted genes in different environments by comparing three different B. subtilis biofilm adaptation settings. The results demonstrate a common evolutionary pattern when B. subtilis is adapting to the plant rhizosphere in similar conditions, and reveal differences in genetic mechanisms between different host plants. These findings will likely support strain improvements for sustainable agriculture.
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Affiliation(s)
- Guohai Hu
- China National GeneBank, BGI-Shenzhen, Shenzhen 518120, PR China
- BGI-Shenzhen, Shenzhen 518083, PR China
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Yue Wang
- China National GeneBank, BGI-Shenzhen, Shenzhen 518120, PR China
- BGI-Shenzhen, Shenzhen 518083, PR China
- BGI-Beijing, Beijing 102601, PR China
| | - Christopher Blake
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Mathilde Nordgaard
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Xin Liu
- China National GeneBank, BGI-Shenzhen, Shenzhen 518120, PR China
- BGI-Shenzhen, Shenzhen 518083, PR China
- BGI-Beijing, Beijing 102601, PR China
| | - Bo Wang
- China National GeneBank, BGI-Shenzhen, Shenzhen 518120, PR China
- BGI-Shenzhen, Shenzhen 518083, PR China
- Shenzhen Key Laboratory of Environmental Microbial Genomics and Application, BGI Shenzhen, 518083 Shenzhen, PR China
| | - Ákos T. Kovács
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, 2800 Lyngby, Denmark
- Institute of Biology Leiden, Leiden University, 2333BE Leiden, Netherlands
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6
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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: 12] [Impact Index Per Article: 6.0] [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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7
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Nordgaard M, Blake C, Maróti G, Hu G, Wang Y, Strube ML, Kovács ÁT. Experimental evolution of Bacillus subtilis on Arabidopsis thaliana roots reveals fast adaptation and improved root colonization. iScience 2022; 25:104406. [PMID: 35663012 PMCID: PMC9157203 DOI: 10.1016/j.isci.2022.104406] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 01/22/2022] [Accepted: 05/05/2022] [Indexed: 12/16/2022] Open
Abstract
Bacillus subtilis is known to promote plant growth and protect plants against disease. B. subtilis rapidly adapts to Arabidopsis thaliana root colonization, as evidenced by improved root colonizers already after 12 consecutive transfers between seedlings in a hydroponic setup. Re-sequencing of single evolved isolates and endpoint populations revealed mutations in genes related to different bacterial traits, in accordance with evolved isolates displaying increased root colonization associated with robust biofilm formation in response to the plant polysaccharide xylan and impaired motility. Interestingly, evolved isolates suffered a fitness disadvantage in a non-selective environment, demonstrating an evolutionary cost of adaptation to the plant root. Finally, increased root colonization by an evolved isolate was also demonstrated in the presence of resident soil microbes. Our findings highlight how a plant growth-promoting rhizobacterium rapidly adapts to an ecologically relevant environment and reveal evolutionary consequences that are fundamental to consider when evolving strains for biocontrol purposes. Bacillus subtilis shows fast adaptation to Arabidopsis thaliana roots in a hydroponic setup Evolved isolates exhibit robust biofilms in response to xylan and impaired motility Adaptation to A. thaliana roots is accompanied by an evolutionary cost An evolved isolate shows higher root colonization in the presence of soil bacteria
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Affiliation(s)
- Mathilde Nordgaard
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Christopher Blake
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Gergely Maróti
- Institute of Plant Biology, Biological Research Centre, Eötvös Loránd Research Network (ELKH), 6726 Szeged, Hungary
| | - Guohai Hu
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark.,China National GeneBank, BGI-Shenzhen, 518120 Shenzhen, China
| | - Yue Wang
- China National GeneBank, BGI-Shenzhen, 518120 Shenzhen, China.,BGI-Beijing, BGI-Shenzhen, 100101 Beijing, China
| | - Mikael Lenz Strube
- Bacterial Ecophysiology and Biotechnology Group, DTU Bioengineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Ákos T Kovács
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
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8
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Zeng Z, Lin S, Li Q, Wang W, Wang Y, Xiao T, Guo Y. Molecular Basis of Wrinkled Variants Isolated From Pseudoalteromonas lipolytica Biofilms. Front Microbiol 2022; 13:797197. [PMID: 35295294 PMCID: PMC8919034 DOI: 10.3389/fmicb.2022.797197] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 01/31/2022] [Indexed: 11/13/2022] Open
Abstract
Many Pseudoalteromonas species are dominant biofilm-forming Gammaproteobacteria in the ocean. The formation of Pseudoalteromonas biofilms is often accompanied by the occurrence of variants with different colony morphologies that may exhibit increased marine antifouling or anticorrosion activities. However, the genetic basis of the occurrence of these variants remains largely unexplored. In this study, we identified that wrinkled variants of P. lipolytica mainly arose due to mutations in the AT00_08765, a wspF-like gene, that are associated with decreased swimming motility and increased cellulose production. Moreover, we found that the spontaneous mutation in flhA, encoding a flagellar biosynthesis protein, also caused a wrinkled colony morphology that is associated with cellulose overproduction, indicating that flhA plays a dual role in controlling flagellar assembly and polysaccharide production in P. lipolytica. Investigation of wrinkled variants harboring spontaneous mutation in dgcB, encoding a GGDEF domain protein, also demonstrated dgcB plays an important role in regulating cellulose production and swimming motility. In addition, by screening the suppressor of the AT00_08765 variant strain, we also identified that the spontaneous mutation in cheR and bcsC directly abolished the wrinkled phenotype of the AT00_08765 variant strain, suggesting that the chemosensory signaling transduction and cellulose production are crucial for the determination of the wrinkled phenotype in P. lipolytica. Taken together, this study provides insights into the genetic variation within biofilms of P. lipolytica.
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Affiliation(s)
- Zhenshun Zeng
- Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, School of Environmental Science and Engineering, Guangzhou University, Guangzhou, China
| | - Shituan Lin
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Qian Li
- Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, School of Environmental Science and Engineering, Guangzhou University, Guangzhou, China
| | - Weiquan Wang
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yuqi Wang
- Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, School of Environmental Science and Engineering, Guangzhou University, Guangzhou, China
| | - Tangfu Xiao
- Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, School of Environmental Science and Engineering, Guangzhou University, Guangzhou, China
- State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu, China
| | - Yuexue Guo
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Sciences, Beijing, China
- *Correspondence: Yuexue Guo,
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9
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Xu A, Zhang X, Wang T, Xin F, Ma LZ, Zhou J, Dong W, Jiang M. Rugose small colony variant and its hyper-biofilm in Pseudomonas aeruginosa: Adaption, evolution, and biotechnological potential. Biotechnol Adv 2021; 53:107862. [PMID: 34718136 DOI: 10.1016/j.biotechadv.2021.107862] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 10/23/2021] [Accepted: 10/24/2021] [Indexed: 12/16/2022]
Abstract
One of the hallmarks of the environmental bacterium Pseudomonas aeruginosa is its excellent ecological flexibility, which can thrive in diverse ecological niches. In different ecosystems, P. aeruginosa may use different strategies to survive, such as forming biofilms in crude oil environment, converting to mucoid phenotype in the cystic fibrosis (CF) lung, or becoming persisters when treated with antibiotics. Rugose small colony variants (RSCVs) are the adaptive mutants of P. aeruginosa, which can be frequently isolated from chronic infections. During the past years, there has been a renewed interest in using P. aeruginosa as a model organism to investigate the RSCVs formation, persistence and pathogenesis, as RSCVs represent a hyper-biofilm formation, high adaptability, high-tolerance sub-population in biofilms. This review will briefly summarize recent advances regarding the phenotypic, genetic and host interaction associated with RSCVs, with an emphasis on P. aeruginosa. Meanwhile, some non-pathogenic bacteria such as Pseudomonas fluorescence, Pseudomonas putida and Bacillus subtilis will be also included. Remarkable emphasis is given on intrinsic functions of such hyper-biofilm formation characteristic as well as its potential applications in several biocatalytic transformations including wastewater treatment, microbial fermentation, and plastic degradation. Hopefully, this review will attract the interest of researchers in various fields and shape future research focused not only on evolutionary biology but also on biotechnological applications related to RSCVs.
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Affiliation(s)
- Anming Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, China.
| | - Xiaoxiao Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, China
| | - Tong Wang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, China
| | - Fengxue Xin
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, China
| | - Luyan Z Ma
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Jie Zhou
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, China.
| | - Weiliang Dong
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, China.
| | - Min Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, China
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10
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Lin Y, Alstrup M, Pang JKY, Maróti G, Er-Rafik M, Tourasse N, Økstad OA, Kovács ÁT. Adaptation of Bacillus thuringiensis to Plant Colonization Affects Differentiation and Toxicity. mSystems 2021; 6:e0086421. [PMID: 34636664 PMCID: PMC8510532 DOI: 10.1128/msystems.00864-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 09/27/2021] [Indexed: 01/11/2023] Open
Abstract
The Bacillus cereus group (Bacillus cereus sensu lato) has a diverse ecology, including various species that are vertebrate or invertebrate pathogens. Few isolates from the B. cereus group have however been demonstrated to benefit plant growth. Therefore, it is crucial to explore how bacterial development and pathogenesis evolve during plant colonization. Herein, we investigated Bacillus thuringiensis (Cry-) adaptation to the colonization of Arabidopsis thaliana roots and monitored changes in cellular differentiation in experimentally evolved isolates. Isolates from two populations displayed improved iterative ecesis on roots and increased virulence against insect larvae. Molecular dissection and recreation of a causative mutation revealed the importance of a nonsense mutation in the rho transcription terminator gene. Transcriptome analysis revealed how Rho impacts various B. thuringiensis genes involved in carbohydrate metabolism and virulence. Our work suggests that evolved multicellular aggregates have a fitness advantage over single cells when colonizing plants, creating a trade-off between swimming and multicellularity in evolved lineages, in addition to unrelated alterations in pathogenicity. IMPORTANCE Biologicals-based plant protection relies on the use of safe microbial strains. During application of biologicals to the rhizosphere, microbes adapt to the niche, including genetic mutations shaping the physiology of the cells. Here, the experimental evolution of Bacillus thuringiensis lacking the insecticide crystal toxins was examined on the plant root to reveal how adaptation shapes the differentiation of this bacterium. Interestingly, evolution of certain lineages led to increased hemolysis and insect larva pathogenesis in B. thuringiensis driven by transcriptional rewiring. Further, our detailed study reveals how inactivation of the transcription termination protein Rho promotes aggregation on the plant root in addition to altered differentiation and pathogenesis in B. thuringiensis.
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Affiliation(s)
- Yicen Lin
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, Lyngby, Denmark
| | - Monica Alstrup
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, Lyngby, Denmark
| | - Janet Ka Yan Pang
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, Lyngby, Denmark
| | - Gergely Maróti
- Institute of Plant Biology, Biological Research Centre of the Hungarian Academy of Sciences, Szeged, Hungary
| | - Mériem Er-Rafik
- National Centre for Nano Fabrication and Characterization, Technical University of Denmark, Lyngby, Denmark
| | - Nicolas Tourasse
- Université Bordeaux, CNRS, INSERM, ARNA, UMR 5320, U1212, Bordeaux, France
| | - Ole Andreas Økstad
- Centre for Integrative Microbial Evolution, University of Oslo, Oslo, Norway
- Section for Pharmacology and Pharmaceutical Biosciences, Department of Pharmacy, University of Oslo, Oslo, Norway
| | - Ákos T. Kovács
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, Lyngby, Denmark
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11
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Predatory Bacteria Select for Sustained Prey Diversity. Microorganisms 2021; 9:microorganisms9102079. [PMID: 34683400 PMCID: PMC8540638 DOI: 10.3390/microorganisms9102079] [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: 07/17/2021] [Revised: 09/22/2021] [Accepted: 09/23/2021] [Indexed: 11/17/2022] Open
Abstract
Predator impacts on prey diversity are often studied among higher organisms over short periods, but microbial predator-prey systems allow examination of prey-diversity dynamics over evolutionary timescales. We previously showed that Escherichia coli commonly evolved minority mucoid phenotypes in response to predation by the bacterial predator Myxococcus xanthus by one time point of a coevolution experiment now named MyxoEE-6. Here we examine mucoid frequencies across several MyxoEE-6 timepoints to discriminate between the hypotheses that mucoids were increasing to fixation, stabilizing around equilibrium frequencies, or heading to loss toward the end of MyxoEE-6. In four focal coevolved prey populations, mucoids rose rapidly early in the experiment and then fluctuated within detectable minority frequency ranges through the end of MyxoEE-6, generating frequency dynamics suggestive of negative frequency-dependent selection. However, a competition experiment between mucoid and non-mucoid clones found a predation-specific advantage of the mucoid clone that was insensitive to frequency over the examined range, leaving the mechanism that maintains minority mucoidy unresolved. The advantage of mucoidy under predation was found to be associated with reduced population size after growth (productivity) in the absence of predators, suggesting a tradeoff between productivity and resistance to predation that we hypothesize may reverse mucoid vs non-mucoid fitness ranks within each MyxoEE-6 cycle. We also found that mucoidy was associated with diverse colony phenotypes and diverse candidate mutations primarily localized in the exopolysaccharide operon yjbEFGH. Collectively, our results show that selection from predatory bacteria can generate apparently stable sympatric phenotypic polymorphisms within coevolving prey populations and also allopatric diversity across populations by selecting for diverse mutations and colony phenotypes associated with mucoidy. More broadly, our results suggest that myxobacterial predation increases long-term diversity within natural microbial communities.
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12
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Blake C, Nordgaard M, Maróti G, Kovács ÁT. Diversification of Bacillus subtilis during experimental evolution on Arabidopsis thaliana and the complementarity in root colonization of evolved subpopulations. Environ Microbiol 2021; 23:6122-6136. [PMID: 34296794 DOI: 10.1111/1462-2920.15680] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Revised: 07/16/2021] [Accepted: 07/19/2021] [Indexed: 12/17/2022]
Abstract
The soil bacterium Bacillus subtilis is known to suppress pathogens as well as promote plant growth. However, in order to fully exploit the potential as natural fertilizer, we need a better understanding of the interactions between B. subtilis and plants. Here, B. subtilis was examined for root colonization through experimental evolution on Arabidopsis thaliana. The populations evolved rapidly, improved in root colonization and diversified into three distinct morphotypes. In order to better understand the adaptation that had taken place, single evolved isolates from the final transfer were randomly selected for further characterization, revealing changes in growth and pellicle formation in medium supplemented with plant polysaccharides. Intriguingly, certain evolved isolates showed improved root colonization only on the plant species they evolved on, but not on another plant species, namely tomato, suggesting A. thaliana specific adaption paths. Finally, the mix performed better than the sum of its constituents in monoculture, which was demonstrated to be caused by complementarity effects. Our results suggest that genetic diversification occurs in an ecological relevant setting on plant roots and proves to be a stable strategy for root colonization.
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Affiliation(s)
- Christopher Blake
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, Kongens Lyngby, 2800, Denmark
| | - Mathilde Nordgaard
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, Kongens Lyngby, 2800, Denmark
| | - Gergely Maróti
- Institute of Plant Biology, Biological Research Centre of the Hungarian Academy of Sciences, Szeged, 6726, Hungary
| | - Ákos T Kovács
- Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, Kongens Lyngby, 2800, Denmark
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13
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Dragoš A, Priyadarshini B, Hasan Z, Strube ML, Kempen PJ, Maróti G, Kaspar C, Bose B, Burton BM, Bischofs IB, Kovács ÁT. Pervasive prophage recombination occurs during evolution of spore-forming Bacilli. ISME JOURNAL 2020; 15:1344-1358. [PMID: 33343000 DOI: 10.1038/s41396-020-00854-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 11/12/2020] [Accepted: 11/20/2020] [Indexed: 02/06/2023]
Abstract
Phages are the main source of within-species bacterial diversity and drivers of horizontal gene transfer, but we know little about the mechanisms that drive genetic diversity of these mobile genetic elements (MGEs). Recently, we showed that a sporulation selection regime promotes evolutionary changes within SPβ prophage of Bacillus subtilis, leading to direct antagonistic interactions within the population. Herein, we reveal that under a sporulation selection regime, SPβ recombines with low copy number phi3Ts phage DNA present within the B. subtilis population. Recombination results in a new prophage occupying a different integration site, as well as the spontaneous release of virulent phage hybrids. Analysis of Bacillus sp. strains suggests that SPβ and phi3T belong to a distinct cluster of unusually large phages inserted into sporulation-related genes that are equipped with a spore-related genetic arsenal. Comparison of Bacillus sp. genomes indicates that similar diversification of SPβ-like phages takes place in nature. Our work is a stepping stone toward empirical studies on phage evolution, and understanding the eco-evolutionary relationships between bacteria and their phages. By capturing the first steps of new phage evolution, we reveal striking relationship between survival strategy of bacteria and evolution of their phages.
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Affiliation(s)
- Anna Dragoš
- Bacterial Interactions and Evolution Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800, Kongens Lyngby, Denmark.
| | - B Priyadarshini
- Bacterial Interactions and Evolution Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - Zahraa Hasan
- Bacterial Interactions and Evolution Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - Mikael Lenz Strube
- Bacterial Ecophysiology and Biotechnology Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - Paul J Kempen
- Department of Health Technology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - Gergely Maróti
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, H-6701, Hungary
| | - Charlotte Kaspar
- BioQuant Center of the University of Heidelberg, 69120, Heidelberg, Germany.,Max-Planck-Institute for Terrestrial Microbiology, 35043, Marburg, Germany
| | | | - Briana M Burton
- Department of Bacteriology, University of Wisconsin, Madison, WI, 53706, USA
| | - Ilka B Bischofs
- BioQuant Center of the University of Heidelberg, 69120, Heidelberg, Germany.,Max-Planck-Institute for Terrestrial Microbiology, 35043, Marburg, Germany
| | - Ákos T Kovács
- Bacterial Interactions and Evolution Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800, Kongens Lyngby, Denmark.
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14
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Otto SB, Martin M, Schäfer D, Hartmann R, Drescher K, Brix S, Dragoš A, Kovács ÁT. Privatization of Biofilm Matrix in Structurally Heterogeneous Biofilms. mSystems 2020; 5:e00425-20. [PMID: 32753507 PMCID: PMC7406226 DOI: 10.1128/msystems.00425-20] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 07/13/2020] [Indexed: 12/19/2022] Open
Abstract
The self-produced biofilm provides beneficial protection for the enclosed cells, but the costly production of matrix components makes producer cells susceptible to cheating by nonproducing individuals. Despite detrimental effects of nonproducers, biofilms can be heterogeneous, with isogenic nonproducers being a natural consequence of phenotypic differentiation processes. For instance, in Bacillus subtilis biofilm cells differ in production of the two major matrix components, the amyloid fiber protein TasA and exopolysaccharides (EPS), demonstrating different expression levels of corresponding matrix genes. This raises questions regarding matrix gene expression dynamics during biofilm development and the impact of phenotypic nonproducers on biofilm robustness. Here, we show that biofilms are structurally heterogeneous and can be separated into strongly and weakly associated clusters. We reveal that spatiotemporal changes in structural heterogeneity correlate with matrix gene expression, with TasA playing a key role in biofilm integrity and timing of development. We show that the matrix remains partially privatized by the producer subpopulation, where cells tightly stick together even when exposed to shear stress. Our results support previous findings on the existence of "weak points" in seemingly robust biofilms as well as on the key role of linkage proteins in biofilm formation. Furthermore, we provide a starting point for investigating the privatization of common goods within isogenic populations.IMPORTANCE Biofilms are communities of bacteria protected by a self-produced extracellular matrix. The detrimental effects of nonproducing individuals on biofilm development raise questions about the dynamics between community members, especially when isogenic nonproducers exist within wild-type populations. We asked ourselves whether phenotypic nonproducers impact biofilm robustness, and where and when this heterogeneity of matrix gene expression occurs. Based on our results, we propose that the matrix remains partly privatized by the producing subpopulation, since producing cells stick together when exposed to shear stress. The important role of linkage proteins in robustness and development of the structurally heterogeneous biofilm provides an entry into studying the privatization of common goods within isogenic populations.
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Affiliation(s)
- Simon B Otto
- Bacterial Interactions and Evolution Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Marivic Martin
- Bacterial Interactions and Evolution Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
- Terrestrial Biofilms Group, Institute of Microbiology, Friedrich Schiller University Jena, Jena, Germany
| | - Daniel Schäfer
- Terrestrial Biofilms Group, Institute of Microbiology, Friedrich Schiller University Jena, Jena, Germany
| | - Raimo Hartmann
- Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Knut Drescher
- Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
- Department of Physics, Philipps-Universität Marburg, Marburg, Germany
| | - Susanne Brix
- Disease Systems Immunology Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Anna Dragoš
- Bacterial Interactions and Evolution Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Ákos T Kovács
- Bacterial Interactions and Evolution Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
- Terrestrial Biofilms Group, Institute of Microbiology, Friedrich Schiller University Jena, Jena, Germany
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15
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Koza A, Jerdan R, Cameron S, Spiers AJ. Three biofilm types produced by a model pseudomonad are differentiated by structural characteristics and fitness advantage. MICROBIOLOGY-SGM 2020; 166:707-716. [PMID: 32520698 DOI: 10.1099/mic.0.000938] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Model bacterial biofilm systems suggest that bacteria produce one type of biofilm, which is then modified by environmental and physiological factors, although the diversification of developing populations might result in the appearance of adaptive mutants producing altered structures with improved fitness advantage. Here we compare the air-liquid (A-L) interface viscous mass (VM) biofilm produced by Pseudomonas fluorescens SBW25 and the wrinkly spreader (WS) and complementary biofilm-forming strain (CBFS) biofilm types produced by adaptive SBW25 mutants in order to better understand the link between these physical structures and the fitness advantage they provide in experimental microcosms. WS, CBFS and VM biofilms can be differentiated by strength, attachment levels and rheology, as well as by strain characteristics associated with biofilm formation. Competitive fitness assays demonstrate that they provide similar advantages under static growth conditions but respond differently to increasing levels of physical disturbance. Pairwise competitions between biofilms suggest that these strains must be competing for at least two growth-limiting resources at the A-L interface, most probably O2 and nutrients, although VM and CBFS cells located lower down in the liquid column might provide an additional fitness advantage through the colonization of a less competitive zone below the biofilm. Our comparison of different SBW25 biofilm types illustrates more generally how varied biofilm characteristics and fitness advantage could become among adaptive mutants arising from an ancestral biofilm-forming strain and raises the question of how significant these changes might be in a range of medical, biotechnological and industrial contexts where diversification and change may be problematic.
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Affiliation(s)
- Anna Koza
- School of Applied Sciences, Abertay University, Bell Street, Dundee DD1 1HG, UK
| | - Robyn Jerdan
- School of Applied Sciences, Abertay University, Bell Street, Dundee DD1 1HG, UK
| | - Scott Cameron
- School of Applied Sciences, Abertay University, Bell Street, Dundee DD1 1HG, UK
| | - Andrew J Spiers
- School of Applied Sciences, Abertay University, Bell Street, Dundee DD1 1HG, UK
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16
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Martin M, Dragoš A, Otto SB, Schäfer D, Brix S, Maróti G, Kovács ÁT. Cheaters shape the evolution of phenotypic heterogeneity in Bacillus subtilis biofilms. ISME JOURNAL 2020; 14:2302-2312. [PMID: 32483306 PMCID: PMC7608354 DOI: 10.1038/s41396-020-0685-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 05/06/2020] [Accepted: 05/13/2020] [Indexed: 01/18/2023]
Abstract
Biofilms are closely packed cells held and shielded by extracellular matrix composed of structural proteins and exopolysaccharides (EPS). As matrix components are costly to produce and shared within the population, EPS-deficient cells can act as cheaters by gaining benefits from the cooperative nature of EPS producers. Remarkably, genetically programmed EPS producers can also exhibit phenotypic heterogeneity at single-cell level. Previous studies have shown that spatial structure of biofilms limits the spread of cheaters, but the long-term influence of cheating on biofilm evolution is not well understood. Here, we examine the influence of EPS nonproducers on evolution of matrix production within the populations of EPS producers in a model biofilm-forming bacterium, Bacillus subtilis. We discovered that general adaptation to biofilm lifestyle leads to an increase in phenotypical heterogeneity of eps expression. However, prolonged exposure to EPS-deficient cheaters may result in different adaptive strategy, where eps expression increases uniformly within the population. We propose a molecular mechanism behind such adaptive strategy and demonstrate how it can benefit the EPS producers in the presence of cheaters. This study provides additional insights on how biofilms adapt and respond to stress caused by exploitation in long-term scenario.
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Affiliation(s)
- Marivic Martin
- Bacterial Interactions and Evolution Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800, Kongens Lyngby, Denmark.,Terrestrial Biofilms Group, Friedrich Schiller University Jena, 07743, Jena, Germany
| | - Anna Dragoš
- Bacterial Interactions and Evolution Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - Simon B Otto
- Bacterial Interactions and Evolution Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - Daniel Schäfer
- Terrestrial Biofilms Group, Friedrich Schiller University Jena, 07743, Jena, Germany
| | - Susanne Brix
- Disease Systems Immunology Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - Gergely Maróti
- Institute of Plant Biology, Biological Research Center of the Hungarian Academy of Sciences, Szeged, 6726, Hungary
| | - Ákos T Kovács
- Bacterial Interactions and Evolution Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800, Kongens Lyngby, Denmark. .,Terrestrial Biofilms Group, Friedrich Schiller University Jena, 07743, Jena, Germany.
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17
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Polonca S. Environment Shapes the Intra-species Diversity of Bacillus subtilis Isolates. MICROBIAL ECOLOGY 2020; 79:853-864. [PMID: 31707464 DOI: 10.1007/s00248-019-01455-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Accepted: 10/23/2019] [Indexed: 06/10/2023]
Abstract
Cosmopolitan bacteria are those that are found practically everywhere in the world. One of them is Bacillus subtilis, which can travel around the world through dust storms rising from various deserts. Upon landing, bacterial survival is determined by the ability to adjust to the heterogonous environments and bacteria isolated from extremely different environments, such as desert and riverbank soil, are expected to be less related due to the environmental pressure of each region. However, little is known about the influence of soil and habitat on B. subtilis evolution. Here, we show that desert and riverbank B. subtilis strains differ in genetic relatedness and physiological traits, such as biofilm morphology and utilisation of carbon sources. Desert strains showed more diversity at the genetic level and were able to utilise more carbon sources than riverbank strains which were highly genetically conserved. Biofilm morphologies of desert and riverbank strains generally segregated and both groups formed different morphology clusters despite the astonishing diversity observed among riverbank strains. We also show that relatedness of B. subtilis strains does not decrease with distance inside the same habitat, which, together with diversity data implies that the difference in environmental selection pressures plays a fundamental role in the evolution of this species.
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Affiliation(s)
- Stefanic Polonca
- Biotechnical Faculty, University of Ljubljana, 1000, Ljubljana, Slovenia.
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18
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Falcón García C, Kretschmer M, Lozano-Andrade CN, Schönleitner M, Dragoŝ A, Kovács ÁT, Lieleg O. Metal ions weaken the hydrophobicity and antibiotic resistance of Bacillus subtilis NCIB 3610 biofilms. NPJ Biofilms Microbiomes 2020; 6:1. [PMID: 31908831 PMCID: PMC6941983 DOI: 10.1038/s41522-019-0111-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 12/03/2019] [Indexed: 02/06/2023] Open
Abstract
Surface superhydrophobicity makes bacterial biofilms very difficult to fight, and it is a combination of their matrix composition and complex surface roughness which synergistically protects these biomaterials from wetting. Although trying to eradicate biofilms with aqueous (antibiotic) solutions is common practice, this can be a futile approach if the biofilms have superhydrophobic properties. To date, there are not many options available to reduce the liquid repellency of biofilms or to prevent this material property from developing. Here, we present a solution to this challenge. We demonstrate how the addition of metal ions such as copper and zinc during or after biofilm formation can render the surface of otherwise superhydrophobic B. subtilis NCIB 3610 biofilms completely wettable. As a result of this procedure, these smoother, hydrophilic biofilms are more susceptible to aqueous antibiotics solutions. Our strategy proposes a scalable and widely applicable step in a multi-faceted approach to eradicate biofilms.
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Affiliation(s)
- Carolina Falcón García
- Department of Mechanical Engineering and Munich School of Bioengineering, Technical University of Munich, Boltzmannstraße 11, 85748 Garching, Germany
| | - Martin Kretschmer
- Department of Mechanical Engineering and Munich School of Bioengineering, Technical University of Munich, Boltzmannstraße 11, 85748 Garching, Germany
| | - Carlos N. Lozano-Andrade
- Bacterial Interactions and Evolution Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 221, 2800 Kongens Lyngby, Denmark
| | - Markus Schönleitner
- Department of Mechanical Engineering and Munich School of Bioengineering, Technical University of Munich, Boltzmannstraße 11, 85748 Garching, Germany
| | - Anna Dragoŝ
- Bacterial Interactions and Evolution Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 221, 2800 Kongens Lyngby, Denmark
| | - Ákos T. Kovács
- Bacterial Interactions and Evolution Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 221, 2800 Kongens Lyngby, Denmark
| | - Oliver Lieleg
- Department of Mechanical Engineering and Munich School of Bioengineering, Technical University of Munich, Boltzmannstraße 11, 85748 Garching, Germany
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19
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Influence of Phenotypic Dissociation in Bacillus subtilis Strain ET-1 on Iturin A Production. Curr Microbiol 2019; 76:1487-1494. [PMID: 31494740 DOI: 10.1007/s00284-019-01764-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 08/26/2019] [Indexed: 10/26/2022]
Abstract
Iturin A is a very important cyclic lipopeptide produced by several B. subtilis strains and has large commercial and therapeutic application potentials but its production on industrial scale has not been realized yet. In the present study, we have observed that the strain ET-1 of Bacillus subtilis, a producer of Iturin A, can present at least three different colony morphologies, which we arbitrarily called Rough, Smooth, and Mucoid morphotypes (R-, S-, and M-form). Performing HPLC analysis, a significant difference between the amounts of Iturin A produced by the three morphotypes was found. The morphotype R-form showed the highest productivity with yields about 10 and 100 times higher than morphotypes S and M, respectively. The results show that the production of Iturin A by B. subtilis could be strongly influenced by the phenotypic heterogeneity of cells within the inoculum. Indeed, we have observed that, pasteurizing the inoculum before seeding in order to improve the homogeneity removing the phenotypes less able to synthesize the Iturin A, its yields in a bench-scale production could be significantly improved. This can represent an important control factor also at industrial scale to improve the Iturin A yields, the robustness, the replicability, and consequently the cost-effectiveness of fermentation processes.
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20
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Zeng Z, Zhan W, Wang W, Wang P, Tang K, Wang X. Biofilm formation in Pseudoalteromonas lipolytica is related to IS5-like insertions in the capsular polysaccharide operon. FEMS Microbiol Ecol 2019; 95:5488432. [PMID: 31077283 DOI: 10.1093/femsec/fiz065] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Accepted: 05/10/2019] [Indexed: 11/14/2022] Open
Abstract
Bacterial capsular polysaccharides (CPSs) participate in environmental adaptation in diverse bacteria species. However, the role and regulation of CPS production in marine bacteria have remained largely unexplored. We previously reported that both wrinkled and translucent Pseudoalteromonas lipolytica variants with altered polysaccharide production were generated in pellicle biofilm-associated cells. In this study, we observed that translucent variants were generated at a rate of ∼20% in colony biofilms of P. lipolytica cultured on HSLB agar plates for 12 days. The DNA sequencing results revealed that nearly 90% of these variants had an IS5-like element inserted within the coding or promoter regions of nine genes in the cps operon. In contrast, IS5 insertion into the cps operon was not detected in planktonic cells. Furthermore, we demonstrated that the IS5 insertion event inactivated CPS production, which leads to a translucent colony morphology. The CPS-deficient variants showed an increased ability to form attached biofilms but exhibited reduced resistance to sublethal concentrations of antibiotics. Moreover, deleting the DNA repair gene recA significantly decreased the frequency of occurrence of CPS-deficient variants during biofilm formation. Thus, IS insertion into the cps operon is an important mechanism for the production of genetic variants during biofilm formation of marine bacteria.
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Affiliation(s)
- Zhenshun Zeng
- Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, School of Environmental Science and Engineering, Guangzhou University, Guangzhou 510006, China
| | - Waner Zhan
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Weiquan Wang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Pengxia Wang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Kaihao Tang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Xiaoxue Wang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China.,University of Chinese Academy of Sciences, Beijing 100049, China
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21
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Kovács ÁT, Dragoš A. Evolved Biofilm: Review on the Experimental Evolution Studies of Bacillus subtilis Pellicles. J Mol Biol 2019; 431:4749-4759. [PMID: 30769118 DOI: 10.1016/j.jmb.2019.02.005] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Revised: 01/21/2019] [Accepted: 02/04/2019] [Indexed: 12/25/2022]
Abstract
For several decades, laboratory evolution has served as a powerful method to manipulate microorganisms and to explore long-term dynamics in microbial populations. Next to canonical Escherichia coli planktonic cultures, experimental evolution has expanded into alternative cultivation methods and species, opening the doors to new research questions. Bacillus subtilis, the spore-forming and root-colonizing bacterium, can easily develop in the laboratory as a liquid-air interface colonizing pellicle biofilm. Here, we summarize recent findings derived from this tractable experimental model. Clonal pellicle biofilms of B. subtilis can rapidly undergo morphological and genetic diversification creating new ecological interactions, for example, exploitation by biofilm non-producers. Moreover, long-term exposure to such matrix non-producers can modulate cooperation in biofilms, leading to different phenotypic heterogeneity pattern of matrix production with larger subpopulation of "ON" cells. Alternatively, complementary variants of biofilm non-producers, each lacking a distinct matrix component, can engage in a genetic division of labor, resulting in superior biofilm productivity compared to the "generalist" wild type. Nevertheless, inter-genetic cooperation appears to be evanescent and rapidly vanquished by individual biofilm formation strategies altering the amount or the properties of the remaining matrix component. Finally, fast-evolving mobile genetic elements can unpredictably shift intra-species interactions in B. subtilis biofilms. Understanding evolution in clonal biofilm populations will facilitate future studies in complex multispecies biofilms that are more representative of nature.
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Affiliation(s)
- Ákos T Kovács
- Bacterial Interactions and Evolution Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800 Kongens Lyngby, Denmark.
| | - Anna Dragoš
- Bacterial Interactions and Evolution Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800 Kongens Lyngby, Denmark.
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Falcón García C, Stangl F, Götz A, Zhao W, Sieber SA, Opitz M, Lieleg O. Topographical alterations render bacterial biofilms susceptible to chemical and mechanical stress. Biomater Sci 2019; 7:220-232. [DOI: 10.1039/c8bm00987b] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Treatment with concentrated ethanol, saline or glucose solutions smoothens biofilm surface topography and initially superhydrophobic/omniphobic biofilms are rendered hydrophilic.
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Affiliation(s)
- Carolina Falcón García
- Department of Mechanical Engineering and Munich School of Bioengineering
- Technical University of Munich
- 85748 Garching
- Germany
| | - Felix Stangl
- Department of Mechanical Engineering and Munich School of Bioengineering
- Technical University of Munich
- 85748 Garching
- Germany
| | - Alexandra Götz
- Center for NanoScience
- Faculty of Physics
- Ludwig-Maximilians-Universität München
- Munich
- Germany
| | - Weining Zhao
- Department of Chemistry
- Chair for Organic Chemistry II
- Technical University of Munich
- 85748 Garching
- Germany
| | - Stephan A. Sieber
- Department of Chemistry
- Chair for Organic Chemistry II
- Technical University of Munich
- 85748 Garching
- Germany
| | - Madeleine Opitz
- Center for NanoScience
- Faculty of Physics
- Ludwig-Maximilians-Universität München
- Munich
- Germany
| | - Oliver Lieleg
- Department of Mechanical Engineering and Munich School of Bioengineering
- Technical University of Munich
- 85748 Garching
- Germany
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23
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Collapse of genetic division of labour and evolution of autonomy in pellicle biofilms. Nat Microbiol 2018; 3:1451-1460. [PMID: 30297741 DOI: 10.1038/s41564-018-0263-y] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 09/05/2018] [Indexed: 11/08/2022]
Abstract
Closely related microorganisms often cooperate, but the prevalence and stability of cooperation between different genotypes remain debatable. Here, we track the evolution of pellicle biofilms formed through genetic division of labour and ask whether partially deficient partners can evolve autonomy. Pellicles of Bacillus subtilis rely on an extracellular matrix composed of exopolysaccharide (EPS) and the fibre protein TasA. In monocultures, ∆eps and ∆tasA mutants fail to form pellicles, but, facilitated by cooperation, they succeed in co-culture. Interestingly, cooperation collapses on an evolutionary timescale and ∆tasA gradually outcompetes its partner ∆eps. Pellicle formation can evolve independently from division of labour in ∆eps and ∆tasA monocultures, by selection acting on the residual matrix component, TasA or EPS, respectively. Using a set of interdisciplinary tools, we unravel that the TasA producer (∆eps) evolves via an unconventional but reproducible substitution in TasA that modulates the biochemical properties of the protein. Conversely, the EPS producer (ΔtasA) undergoes genetically variable adaptations, all leading to enhanced EPS secretion and biofilms with different biomechanical properties. Finally, we revisit the collapse of division of labour between Δeps and ΔtasA in light of a strong frequency versus exploitability trade-off that manifested in the solitarily evolving partners. We propose that such trade-off differences may represent an additional barrier to evolution of division of labour between genetically distinct microorganisms.
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A single mutation in rapP induces cheating to prevent cheating in Bacillus subtilis by minimizing public good production. Commun Biol 2018; 1:133. [PMID: 30272012 PMCID: PMC6123732 DOI: 10.1038/s42003-018-0136-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 08/10/2018] [Indexed: 12/30/2022] Open
Abstract
Cooperation is beneficial to group behaviors like multicellularity, but is vulnerable to exploitation by cheaters. Here we analyze mechanisms that protect against exploitation of extracellular surfactin in swarms of Bacillus subtilis. Unexpectedly, the reference strain NCIB 3610 displays inherent resistance to surfactin-non-producing cheaters, while a different wild isolate is susceptible. We trace this interstrain difference down to a single amino acid change in the plasmid-borne regulator RapP, which is necessary and sufficient for cheater mitigation. This allele, prevalent in many Bacillus species, optimizes transcription of the surfactin operon to the minimum needed for full cooperation. When combined with a strain lacking rapP, NCIB 3610 acts as a cheater itself—except it does not harm the population at high proportions since it still produces enough surfactin. This strategy of minimal production is thus a doubly advantageous mechanism to limit exploitation of public goods, and is readily evolved from existing regulatory networks. Lyons and Kolter describe a single-point mutation in the plasmid-borne gene rapP of Bacillus subtilis that optimizes surfactin transcription to express the minimum required for cooperation. The decrease in the production of this public good significantly prevented the exploitation of cooperative traits by cheaters.
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25
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Wojciech J, Kamila M, Wojciech B. Investigation of the population dynamics within a Pseudomonas aeruginosa biofilm using a flow based biofilm model system and flow cytometric evaluation of cellular physiology. BIOFOULING 2018; 34:835-850. [PMID: 30332894 DOI: 10.1080/08927014.2018.1508569] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Revised: 07/16/2018] [Accepted: 07/25/2018] [Indexed: 06/08/2023]
Abstract
In this study a flow based biofilm model system was used to simulate the formation of Pseudomonas aeruginosa biofilms on a stainless steel surface. To investigate the complexity of biofilm-associated P. aeruginosa populations a combination of microscopic observations and flow cytometric analysis (FCM) was adopted. Biofilm-associated P. aeruginosa cells were evaluated (1) under optimal vs reduced nutrient-availability at the initial adhesion stage, and (2) irrespective of nutrient-availability within a mature biofilm. Microscopic estimation of the extent of attachment revealed more effective colonization upon optimal vs starvation conditions. FCM allowed an in situ evaluation of P. aeruginosa vitality, using cellular redox potential measurements to discriminate active, mid-active and non-active sub-populations. Samples from recently attached cells and mature biofilms showed significant differences in the percentages of bacterial cells from the defined sub-populations. The approach demonstrated that distribution of individual P. aeruginosa sub-populations was influenced by the stage of the biofilm life-cycle and nutrient availability.
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Affiliation(s)
- Juzwa Wojciech
- a Department of Biotechnology and Food Microbiology , Poznan University of Life Sciences , Poznan , Poland
| | - Myszka Kamila
- a Department of Biotechnology and Food Microbiology , Poznan University of Life Sciences , Poznan , Poland
| | - Białas Wojciech
- a Department of Biotechnology and Food Microbiology , Poznan University of Life Sciences , Poznan , Poland
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Dragoš A, Kiesewalter H, Martin M, Hsu CY, Hartmann R, Wechsler T, Eriksen C, Brix S, Drescher K, Stanley-Wall N, Kümmerli R, Kovács ÁT. Division of Labor during Biofilm Matrix Production. Curr Biol 2018; 28:1903-1913.e5. [PMID: 29887307 DOI: 10.1016/j.cub.2018.04.046] [Citation(s) in RCA: 135] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2018] [Revised: 03/13/2018] [Accepted: 04/13/2018] [Indexed: 01/06/2023]
Abstract
Organisms as simple as bacteria can engage in complex collective actions, such as group motility and fruiting body formation. Some of these actions involve a division of labor, where phenotypically specialized clonal subpopulations or genetically distinct lineages cooperate with each other by performing complementary tasks. Here, we combine experimental and computational approaches to investigate potential benefits arising from division of labor during biofilm matrix production. We show that both phenotypic and genetic strategies for a division of labor can promote collective biofilm formation in the soil bacterium Bacillus subtilis. In this species, biofilm matrix consists of two major components, exopolysaccharides (EPSs) and TasA. We observed that clonal groups of B. subtilis phenotypically segregate into three subpopulations composed of matrix non-producers, EPS producers, and generalists, which produce both EPSs and TasA. This incomplete phenotypic specialization was outperformed by a genetic division of labor, where two mutants, engineered as specialists, complemented each other by exchanging EPSs and TasA. The relative fitness of the two mutants displayed a negative frequency dependence both in vitro and on plant roots, with strain frequency reaching a stable equilibrium at 30% TasA producers, corresponding exactly to the population composition where group productivity is maximized. Using individual-based modeling, we show that asymmetries in strain ratio can arise due to differences in the relative benefits that matrix compounds generate for the collective and that genetic division of labor can be favored when it breaks metabolic constraints associated with the simultaneous production of two matrix components.
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Affiliation(s)
- Anna Dragoš
- Bacterial Interactions and Evolution Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs Lyngby 2800, Denmark; Terrestrial Biofilms Group, Institute of Microbiology, Friedrich Schiller University Jena, Jena 07743, Germany
| | - Heiko Kiesewalter
- Bacterial Interactions and Evolution Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs Lyngby 2800, Denmark
| | - Marivic Martin
- Bacterial Interactions and Evolution Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs Lyngby 2800, Denmark; Terrestrial Biofilms Group, Institute of Microbiology, Friedrich Schiller University Jena, Jena 07743, Germany
| | - Chih-Yu Hsu
- School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Raimo Hartmann
- Max Planck Institute for Terrestrial Microbiology, Marburg 35043, Germany
| | - Tobias Wechsler
- Department of Plant and Microbial Biology, University of Zürich, Zürich 8057, Switzerland
| | - Carsten Eriksen
- Disease Systems Immunology Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs Lyngby 2800, Denmark
| | - Susanne Brix
- Disease Systems Immunology Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs Lyngby 2800, Denmark
| | - Knut Drescher
- Max Planck Institute for Terrestrial Microbiology, Marburg 35043, Germany; Department of Physics, Philipps University, Marburg 35037, Germany
| | | | - Rolf Kümmerli
- Department of Plant and Microbial Biology, University of Zürich, Zürich 8057, Switzerland
| | - Ákos T Kovács
- Bacterial Interactions and Evolution Group, Department of Biotechnology and Biomedicine, Technical University of Denmark, Kgs Lyngby 2800, Denmark; Terrestrial Biofilms Group, Institute of Microbiology, Friedrich Schiller University Jena, Jena 07743, Germany.
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