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Gilhar O, Ben-Navi LR, Olender T, Aharoni A, Friedman J, Kolodkin-Gal I. Multigenerational inheritance drives symbiotic interactions of the bacterium Bacillus subtilis with its plant host. Microbiol Res 2024; 286:127814. [PMID: 38954993 DOI: 10.1016/j.micres.2024.127814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2024] [Revised: 06/04/2024] [Accepted: 06/18/2024] [Indexed: 07/04/2024]
Abstract
Bacillus subtilis is a beneficial bacterium that supports plant growth and protects plants from bacterial, fungal, and viral infections. Using a simplified system of B. subtilis and Arabidopsis thaliana interactions, we studied the fitness and transcriptome of bacteria detached from the root over generations of growth in LB medium. We found that bacteria previously associated with the root or exposed to its secretions had greater stress tolerance and were more competitive in root colonization than bacteria not previously exposed to the root. Furthermore, our transcriptome results provide evidence that plant secretions induce a microbial stress response and fundamentally alter signaling by the cyclic nucleotide c-di-AMP, a signature maintained by their descendants. The changes in cellular physiology due to exposure to plant exudates were multigenerational, as they allowed not only the bacterial cells that colonized a new plant but also their descendants to have an advance over naive competitors of the same species, while the overall plasticity of gene expression and rapid adaptation were maintained. These changes were hereditary but not permanent. Our work demonstrates a bacterial memory manifested by multigenerational reversible adaptation to plant hosts in the form of activation of the stressosome, which confers an advantage to symbiotic bacteria during competition.
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Affiliation(s)
- Omri Gilhar
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel; Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | | | - Tsviya Olender
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Asaph Aharoni
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Jonathan Friedman
- Department of Plant Pathology and Microbiology, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Ilana Kolodkin-Gal
- Scojen Institute for Synthetic Biology, Reichman University, Herzliya, Israel.
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Liang B, Wang H, Yang C, Wang L, Qi L, Guo Z, Chen X. Salicylic Acid Is Required for Broad-Spectrum Disease Resistance in Rice. Int J Mol Sci 2022; 23:ijms23031354. [PMID: 35163275 PMCID: PMC8836234 DOI: 10.3390/ijms23031354] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 01/21/2022] [Accepted: 01/22/2022] [Indexed: 02/04/2023] Open
Abstract
Rice plants contain high basal levels of salicylic acid (SA), but some of their functions remain elusive. To elucidate the importance of SA homeostasis in rice immunity, we characterized four rice SA hydroxylase genes (OsSAHs) and verified their roles in SA metabolism and disease resistance. Recombinant OsSAH proteins catalyzed SA in vitro, while OsSAH3 protein showed only SA 5-hydroxylase (SA5H) activity, which was remarkably higher than that of other OsSAHs that presented both SA3H and SA5H activities. Amino acid substitutions revealed that three amino acids in the binding pocket affected SAH enzyme activity and/or specificity. Knockout OsSAH2 and OsSAH3 (sahKO) genes conferred enhanced resistance to both hemibiotrophic and necrotrophic pathogens, whereas overexpression of each OsSAH gene increased susceptibility to the pathogens. sahKO mutants showed increased SA and jasmonate levels compared to those of the wild type and OsSAH-overexpressing plants. Analysis of the OsSAH3 promoter indicated that its induction was mainly restricted around Magnaporthe oryzae infection sites. Taken together, our findings indicate that SA plays a vital role in immune signaling. Moreover, fine-tuning SA homeostasis through suppression of SA metabolism is an effective approach in studying broad-spectrum disease resistance in rice.
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Zhao L, Liu Q, Huang Q, Liu F, Liu H, Wang G. Isocitrate dehydrogenase of Bacillus cereus is involved in biofilm formation. World J Microbiol Biotechnol 2021; 37:207. [PMID: 34719734 DOI: 10.1007/s11274-021-03175-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 10/19/2021] [Indexed: 11/25/2022]
Abstract
Isocitrate dehydrogenase (IDH), a key enzyme in the TCA cycle, participates in the formation of biofilms in Staphylococcus aureus, but it remains to be clarified whether it is involved in the formation of Bacillus cereus biofilms. In this study, we scanned the genome of B. cereus 0-9 and found a gene encoding isocitrate dehydrogenase (FRY47_22620) named icdH. The IcdH protein was expressed and purified. The enzyme activity assay showed that the protein had IDH activity dependent on NADP+, indicating that this gene encoded an IDH. The ΔicdH mutant and its complemented strains were obtained by a homologous recombination strategy, and crystal violet data and CLSM were measured. The results showed that the biofilm yield of the mutant ΔicdH decreased, and the biofilm morphology also changed, while the growth of ΔicdH was not affected. The extracellular pH and citric acid content results showed that the ΔicdH mutant exhibited citric acid accumulation and acidification of the extracellular matrix. In addition, the addition of excess Fe3+ restored the biofilm formation of the ΔicdH mutant. It is speculated that IDH in B. cereus may regulate biofilm formation by modulating intracellular redox homeostasis. In addition, we found that the icdH deletion of B. cereus 0-9 could result in a reduced sporulation rate, which was significantly different from sporulation in B. subtilis caused by interruption of the stage I sporulation process due to icdH loss. All the above results provide us with new insights for further research on IDH.
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Affiliation(s)
- Linlin Zhao
- Institute of Microbial Engineering, School of Life Science, Hennan Univeristy, Jinming Street, Kaifeng, 475004, Henan, People's Republic of China
| | - Qing Liu
- Institute of Microbial Engineering, School of Life Science, Hennan Univeristy, Jinming Street, Kaifeng, 475004, Henan, People's Republic of China
| | - Qiubin Huang
- Institute of Microbial Engineering, School of Life Science, Hennan Univeristy, Jinming Street, Kaifeng, 475004, Henan, People's Republic of China
- Engineering Research Center for Applied Microbiology, Hennan Province, Kaifeng, Hennan, 475004, People's Republic of China
| | - Fengying Liu
- Institute of Microbial Engineering, School of Life Science, Hennan Univeristy, Jinming Street, Kaifeng, 475004, Henan, People's Republic of China
- Engineering Research Center for Applied Microbiology, Hennan Province, Kaifeng, Hennan, 475004, People's Republic of China
| | - Huiping Liu
- Institute of Microbial Engineering, School of Life Science, Hennan Univeristy, Jinming Street, Kaifeng, 475004, Henan, People's Republic of China
| | - Gang Wang
- Institute of Microbial Engineering, School of Life Science, Hennan Univeristy, Jinming Street, Kaifeng, 475004, Henan, People's Republic of China.
- Engineering Research Center for Applied Microbiology, Hennan Province, Kaifeng, Hennan, 475004, People's Republic of China.
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Above and below-ground involvement in cyclic energy transformation that helps in the establishment of rhizosphere microbial communities. Symbiosis 2021. [DOI: 10.1007/s13199-021-00791-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Synergistic effects of pomegranate and rosemary extracts in combination with antibiotics against antibiotic resistance and biofilm formation of Pseudomonas aeruginosa. Braz J Microbiol 2020; 51:1079-1092. [PMID: 32394240 DOI: 10.1007/s42770-020-00284-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 04/22/2020] [Indexed: 12/20/2022] Open
Abstract
The combination of plant extract and antibiotic represents a template for developing of antibiofilm drugs. This study investigated the synergistic effects of pomegranate/rosemary/antibiotic combinations against antibiotic resistance and biofilm formation of Pseudomonas aeruginosa. The results showed that 17 (85%) of total P. aeruginosa isolates were biofilm producers; however, 5 (25%) isolates were demonstrated as a strong biofilm producer. The highest MIC level (1024 μg/ml) of tested antibiotics against strong biofilm producer isolates was observed with piperacillin, however the MIC ranges of ceftazidime, gentamycin, imipenem, and levofloxacin against these isolates were reached to (256-1024 μg/ml), (32-1024 μg/ml), (8-1024 μg/ml), and (8-512 μg/ml), respectively. PS-1 was the representative isolate for strong biofilm formation and high antibiotic resistance. 16S rRNA gene analysis suggested that PS-1 (accession No. MN619678) was identified as a strain of P. aeruginosa POA1. Pomegranate and rosemary extracts were the most effective extracts in biofilm inhibition, which significantly inhibited 91.93 and 90.83% of PS-1 biofilm, respectively. Notably, the synergism between both plant extracts and antibiotics has significantly reduced the MICs of used antibiotics at the level lower than the susceptibility breakpoints. Pomegranate/rosemary/antibiotic combinations achieved the highest biofilm eradication, which ranging from 90.0 to 99.6%, followed by the eradication ranges of pomegranate/rosemary combination, rosemary, and pomegranate extracts, which reached to (76.5-85.4%), (53.1-73.7%), and (41.2-71.5%), respectively. The findings suggest that pomegranate/rosemary/antibiotic combinations may be an effective therapeutic agent for antibiotic resistance and biofilm formation of P. aeruginosa.
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Odelade KA, Babalola OO. Bacteria, Fungi and Archaea Domains in Rhizospheric Soil and Their Effects in Enhancing Agricultural Productivity. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2019; 16:E3873. [PMID: 31614851 PMCID: PMC6843647 DOI: 10.3390/ijerph16203873] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 09/19/2019] [Accepted: 10/04/2019] [Indexed: 12/24/2022]
Abstract
The persistent and undiscriminating application of chemicals as means to improve crop growth, development and yields for several years has become problematic to agricultural sustainability because of the adverse effects these chemicals have on the produce, consumers and beneficial microbes in the ecosystem. Therefore, for agricultural productivity to be sustained there are needs for better and suitable preferences which would be friendly to the ecosystem. The use of microbial metabolites has become an attractive and more feasible preference because they are versatile, degradable and ecofriendly, unlike chemicals. In order to achieve this aim, it is then imperative to explore microbes that are very close to the root of a plant, especially where they are more concentrated and have efficient activities called the rhizosphere. Extensive varieties of bacteria, archaea, fungi and other microbes are found inhabiting the rhizosphere with various interactions with the plant host. Therefore, this review explores various beneficial microbes such as bacteria, fungi and archaea and their roles in the environment in terms of acquisition of nutrients for plants for the purposes of plant growth and health. It also discusses the effect of root exudate on the rhizosphere microbiome and compares the three domains at molecular levels.
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Affiliation(s)
- Kehinde Abraham Odelade
- Food Security and Safety Niche Area, Faculty of Natural and Agricultural Science, North-West University, Private Bag X2046, Mmabatho 2735, South Africa.
| | - Olubukola Oluranti Babalola
- Food Security and Safety Niche Area, Faculty of Natural and Agricultural Science, North-West University, Private Bag X2046, Mmabatho 2735, South Africa.
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Malinich EA, Wang K, Mukherjee PK, Kolomiets M, Kenerley CM. Differential expression analysis of Trichoderma virens RNA reveals a dynamic transcriptome during colonization of Zea mays roots. BMC Genomics 2019; 20:280. [PMID: 30971198 PMCID: PMC6458689 DOI: 10.1186/s12864-019-5651-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Accepted: 03/27/2019] [Indexed: 12/16/2022] Open
Abstract
Background Trichoderma spp. are majorly composed of plant-beneficial symbionts widely used in agriculture as bio-control agents. Studying the mechanisms behind Trichoderma-derived plant benefits has yielded tangible bio-industrial products. To better take advantage of this fungal-plant symbiosis it is necessary to obtain detailed knowledge of which genes Trichoderma utilizes during interaction with its plant host. In this study, we explored the transcriptional activity undergone by T. virens during two phases of symbiosis with maize; recognition of roots and after ingress into the root cortex. Results We present a model of T. virens – maize interaction wherein T. virens experiences global repression of transcription upon recognition of maize roots and then induces expression of a broad spectrum of genes during colonization of maize roots. The genes expressed indicate that, during colonization of maize roots, T. virens modulates biosynthesis of phytohormone-like compounds, secretes a plant-environment specific array of cell wall degrading enzymes and secondary metabolites, remodels both actin-based and cell membrane structures, and shifts metabolic activity. We also highlight transcription factors and signal transduction genes important in future research seeking to unravel the molecular mechanisms of T. virens activity in maize roots. Conclusions T. virens displays distinctly different transcriptional profiles between recognizing the presence of maize roots and active colonization of these roots. A though understanding of these processes will allow development of T. virens as a bio-control agent. Further, the publication of these datasets will target future research endeavors specifically to genes of interest when considering T. virens – maize symbiosis. Electronic supplementary material The online version of this article (10.1186/s12864-019-5651-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Elizabeth A Malinich
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX, USA
| | - Ken Wang
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX, USA
| | - Prasun K Mukherjee
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX, USA
| | - Michael Kolomiets
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX, USA
| | - Charles M Kenerley
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX, USA.
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Al-Ali A, Deravel J, Krier F, Béchet M, Ongena M, Jacques P. Biofilm formation is determinant in tomato rhizosphere colonization by Bacillus velezensis FZB42. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:29910-29920. [PMID: 29063401 DOI: 10.1007/s11356-017-0469-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Accepted: 10/10/2017] [Indexed: 06/07/2023]
Abstract
In this work, the behavior in tomato rhizosphere of Bacillus velezensis FZB42 was analyzed taking into account the surfactin production, the use of tomato roots exudate as substrates, and the biofilm formation. B. velezensis FZB42 and B. amyloliquefaciens S499 have a similar capability to colonize tomato rhizosphere. Little difference in this colonization was observed with surfactin non producing B. velezensis FZB42 mutant strains. B. velezensis is able to grow in the presence of root exudate and used preferentially sucrose, maltose, glutamic, and malic acids as carbon sources. A mutant enable to produce exopolysaccharide (EPS-) was constructed to demonstrate the main importance of biofilm formation on rhizosphere colonization. This mutant had completely lost its ability to form biofilm whatever the substrate present in the culture medium and was unable to efficiently colonize tomato rhizosphere.
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Affiliation(s)
- Ameen Al-Ali
- Université Lille, INRA, ISA, Université Artois, Université Littoral Côte d'Opale, EA 7394-ICV Institut Charles Viollette, F-59000, Lille, France
- College of Agriculture-Soil, Water and Environmental Research Department, Al-Qasim Green University, Babylon, Iraq
| | - Jovana Deravel
- Université Lille, INRA, ISA, Université Artois, Université Littoral Côte d'Opale, EA 7394-ICV Institut Charles Viollette, F-59000, Lille, France
| | - François Krier
- Université Lille, INRA, ISA, Université Artois, Université Littoral Côte d'Opale, EA 7394-ICV Institut Charles Viollette, F-59000, Lille, France.
| | - Max Béchet
- Université Lille, INRA, ISA, Université Artois, Université Littoral Côte d'Opale, EA 7394-ICV Institut Charles Viollette, F-59000, Lille, France
| | - Marc Ongena
- Terra Teaching and Research Centre, Microbial Processes and Interactions (MiPI), Gembloux Agro-Bio Tech, University of Liege, B 5030, Gembloux, Belgium
| | - Philippe Jacques
- Université Lille, INRA, ISA, Université Artois, Université Littoral Côte d'Opale, EA 7394-ICV Institut Charles Viollette, F-59000, Lille, France
- Terra Teaching and Research Centre, Microbial Processes and Interactions (MiPI), Gembloux Agro-Bio Tech, University of Liege, B 5030, Gembloux, Belgium
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Dell'orto S, Cattò C, Villa F, Forlani F, Vassallo E, Morra M, Cappitelli F, Villa S, Gelain A. Low density polyethylene functionalized with antibiofilm compounds inhibits Escherichia coli cell adhesion. J Biomed Mater Res A 2017; 105:3251-3261. [PMID: 28795783 DOI: 10.1002/jbm.a.36183] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 06/29/2017] [Accepted: 08/01/2017] [Indexed: 12/18/2022]
Abstract
The present work concerns an efficient strategy to obtain novel medical devices materials able to inhibit biofilm formation. The new materials were achieved by covalent grafting of p-aminocinnamic or p-aminosalicylic acids on low density polyethylene coupons. The polyethylene surface, previously activated by oxygen plasma treatment, was functionalized using 2-hydroxymethylmetacrylate as linker. The latter was reacted with succinic anhydride affording the carboxylic end useful for the immobilization of the antibiofilm molecules. The modified surface was characterized by scanning electron microscope, X-ray photoelectron spectroscopy, attenuated total reflectance Fourier transform infrared and fluorescence analyses. The antibiofilm activity of the modified materials were tested against Escherichia coli biofilm grown in the Center of Disease Control biofilm reactor. The results revealed that the grafted cinnamic and salicylic acid derivatives reduced biofilm biomass, in comparison with the control, by 73.7 ± 10.7% and 63.4 ± 7.1%, respectively. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 3251-3261, 2017.
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Affiliation(s)
- Silvia Dell'orto
- Department of Pharmaceutical Sciences, Università degli Studi di Milano, Via L. Mangiagalli 25, 20133, Milano, Italy
| | - Cristina Cattò
- Department of Food Environmental and Nutritional Sciences, Università degli Studi di Milano, Via Celoria 2, 20133, Milano, Italy
| | - Federica Villa
- Department of Food Environmental and Nutritional Sciences, Università degli Studi di Milano, Via Celoria 2, 20133, Milano, Italy
| | - Fabio Forlani
- Department of Food Environmental and Nutritional Sciences, Università degli Studi di Milano, Via Celoria 2, 20133, Milano, Italy
| | - Espedito Vassallo
- Institute of Plasma Physics «Piero Caldirola», National Research Council (CNR), Via Roberto Cozzi 53, 20125, Milano, Italy
| | - Marco Morra
- Nobil Bio Ricerche S.r.l, Via Valcastellana 28, 14037, Portacomaro, (AT), Italy
| | - Francesca Cappitelli
- Department of Food Environmental and Nutritional Sciences, Università degli Studi di Milano, Via Celoria 2, 20133, Milano, Italy
| | - Stefania Villa
- Department of Pharmaceutical Sciences, Università degli Studi di Milano, Via L. Mangiagalli 25, 20133, Milano, Italy
| | - Arianna Gelain
- Department of Pharmaceutical Sciences, Università degli Studi di Milano, Via L. Mangiagalli 25, 20133, Milano, Italy
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Zúñiga A, Donoso RA, Ruiz D, Ruz GA, González B. Quorum-Sensing Systems in the Plant Growth-Promoting Bacterium Paraburkholderia phytofirmans PsJN Exhibit Cross-Regulation and Are Involved in Biofilm Formation. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2017; 30:557-565. [PMID: 28548604 DOI: 10.1094/mpmi-01-17-0008-r] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Quorum-sensing systems play important roles in host colonization and host establishment of Burkholderiales species. Beneficial Paraburkholderia species share a conserved quorum-sensing (QS) system, designated BraI/R, that controls different phenotypes. In this context, the plant growth-promoting bacterium Paraburkholderia phytofirmans PsJN possesses two different homoserine lactone QS systems BpI.1/R.1 and BpI.2/R.2 (BraI/R-like QS system). The BpI.1/R.1 QS system was previously reported to be important to colonize and produce beneficial effects in Arabidopsis thaliana plants. Here, we analyzed the temporal variations of the QS gene transcript levels in the wild-type strain colonizing plant roots. The gene expression patterns showed relevant differences in both QS systems compared with the wild-type strain in the unplanted control treatment. The gene expression data were used to reconstruct a regulatory network model of QS systems in P. phytofirmans PsJN, using a Boolean network model. Also, we examined the phenotypic traits and transcript levels of genes involved in QS systems, using P. phytofirmans mutants in homoserine lactone synthases genes. We observed that the BpI.1/R.1 QS system regulates biofilm formation production in strain PsJN and this phenotype was associated with the lower expression of a specific extracytoplasmic function sigma factor ecf26.1 gene (implicated in biofilm formation) in the bpI.1 mutant strain.
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Affiliation(s)
- Ana Zúñiga
- Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Millennium Nucleus Center for Plant Systems and Synthetic Biology, and Center of Applied Ecology and Sustainability (CAPES), Santiago, Chile
| | - Raúl A Donoso
- Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Millennium Nucleus Center for Plant Systems and Synthetic Biology, and Center of Applied Ecology and Sustainability (CAPES), Santiago, Chile
| | - Daniela Ruiz
- Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Millennium Nucleus Center for Plant Systems and Synthetic Biology, and Center of Applied Ecology and Sustainability (CAPES), Santiago, Chile
| | - Gonzalo A Ruz
- Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Millennium Nucleus Center for Plant Systems and Synthetic Biology, and Center of Applied Ecology and Sustainability (CAPES), Santiago, Chile
| | - Bernardo González
- Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Millennium Nucleus Center for Plant Systems and Synthetic Biology, and Center of Applied Ecology and Sustainability (CAPES), Santiago, Chile
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Cattò C, Grazioso G, Dell'Orto S, Gelain A, Villa S, Marzano V, Vitali A, Villa F, Cappitelli F, Forlani F. The response of Escherichia coli biofilm to salicylic acid. BIOFOULING 2017; 33:235-251. [PMID: 28270055 DOI: 10.1080/08927014.2017.1286649] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 01/18/2017] [Indexed: 06/06/2023]
Abstract
In this research, salicylic acid is proposed as an alternative biocide-free agent suitable for a preventive or integrative anti-biofilm approach. Salicylic acid has been proved to: (1) reduce bacterial adhesion up to 68.1 ± 5.6%; (2) affect biofilm structural development, reducing viable biomass by 97.0 ± 0.7% and extracellular proteins and polysaccharides by 83.9 ± 2.5% and 49.5 ± 5.5% respectively; and (3) promote biofilm detachment 3.4 ± 0.6-fold. Moreover, salicylic acid treated biofilm showed an increased amount of intracellular (2.3 ± 0.2-fold) and extracellular (2.1 ± 0.3-fold) reactive oxygen species, and resulted in increased production of the quorum sensing signal indole (7.6 ± 1.4-fold). For the first time, experiments revealed that salicylic acid interacts with proteins that play a role in quorum sensing, reactive oxygen species accumulation, motility, extracellular polymeric matrix components, transport and metabolism.
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Affiliation(s)
- Cristina Cattò
- a Department of Food Environmental and Nutritional Sciences , Università degli Studi di Milano , Milan , Italy
| | - Giovanni Grazioso
- b Department of Pharmaceutical Sciences , Università degli Studi di Milano , Milan , Italy
| | - Silvia Dell'Orto
- b Department of Pharmaceutical Sciences , Università degli Studi di Milano , Milan , Italy
| | - Arianna Gelain
- b Department of Pharmaceutical Sciences , Università degli Studi di Milano , Milan , Italy
| | - Stefania Villa
- b Department of Pharmaceutical Sciences , Università degli Studi di Milano , Milan , Italy
| | - Valeria Marzano
- c Institute of Biochemistry and Clinical Biochemistry , Catholic University , Rome , Italy
| | - Alberto Vitali
- d Institute of Chemistry of Molecular Recognition-UOS Roma , CNR , Rome , Italy
| | - Federica Villa
- a Department of Food Environmental and Nutritional Sciences , Università degli Studi di Milano , Milan , Italy
| | - Francesca Cappitelli
- a Department of Food Environmental and Nutritional Sciences , Università degli Studi di Milano , Milan , Italy
| | - Fabio Forlani
- a Department of Food Environmental and Nutritional Sciences , Università degli Studi di Milano , Milan , Italy
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Paolinelli-Alfonso M, Villalobos-Escobedo JM, Rolshausen P, Herrera-Estrella A, Galindo-Sánchez C, López-Hernández JF, Hernandez-Martinez R. Global transcriptional analysis suggests Lasiodiplodia theobromae pathogenicity factors involved in modulation of grapevine defensive response. BMC Genomics 2016; 17:615. [PMID: 27514986 PMCID: PMC4981995 DOI: 10.1186/s12864-016-2952-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2016] [Accepted: 07/19/2016] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Lasiodiplodia theobromae is a fungus of the Botryosphaeriaceae that causes grapevine vascular disease, especially in regions with hot climates. Fungi in this group often remain latent within their host and become virulent under abiotic stress. Transcriptional regulation analysis of L. theobromae exposed to heat stress (HS) was first carried out in vitro in the presence of grapevine wood (GW) to identify potential pathogenicity genes that were later evaluated for in planta expression. RESULTS A total of 19,860 de novo assembled transcripts were obtained, forty-nine per cent of which showed homology to the Botryosphaeriaceae fungi, Neofusicoccum parvum or Macrophomina phaseolina. Three hundred ninety-nine have homology with genes involved in pathogenic processes and several belonged to expanded gene families in others fungal grapevine vascular pathogens. Gene expression analysis showed changes in fungal metabolism of phenolic compounds; where genes encoding for enzymes, with the ability to degrade salicylic acid (SA) and plant phenylpropanoid precursors, were up-regulated during in vitro HS response, in the presence of GW. These results suggest that the fungal L-tyrosine catabolism pathway could help the fungus to remove phenylpropanoid precursors thereby evading the host defense response. The in planta up-regulation of salicylate hydroxylase, intradiol ring cleavage dioxygenase and fumarylacetoacetase encoding genes, further supported this hypothesis. Those genes were even more up-regulated in HS-stressed plants, suggesting that fungus takes advantage of the increased phenylpropanoid precursors produced under stress. Pectate lyase was up-regulated while a putative amylase was down-regulated in planta, this could be associated with an intercellular growth strategy during the first stages of colonization. CONCLUSIONS L. theobromae transcriptome was established and validated. Its usefulness was demonstrated through the identification of genes expressed during the infection process. Our results support the hypothesis that heat stress facilitates fungal colonization, because of the fungus ability to use the phenylpropanoid precursors and SA, both compounds known to control host defense.
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Affiliation(s)
- Marcos Paolinelli-Alfonso
- Departamento de Microbiología, Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE), Ensenada, BC 22860 Mexico
| | - José Manuel Villalobos-Escobedo
- Laboratorio Nacional de Genómica para la Biodiversidad (LANGEBIO), Centro de Investigación y de Estudios Avanzados del I. P. N., Irapuato, Gto 36821 Mexico
| | - Philippe Rolshausen
- Department of Botany and Plant Sciences,University of California Riverside, Riverside, 92521 CA USA
| | - Alfredo Herrera-Estrella
- Laboratorio Nacional de Genómica para la Biodiversidad (LANGEBIO), Centro de Investigación y de Estudios Avanzados del I. P. N., Irapuato, Gto 36821 Mexico
| | - Clara Galindo-Sánchez
- Departamento de Biotecnología Marina, Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE), Ensenada, BC 22860 Mexico
| | - José Fabricio López-Hernández
- Laboratorio Nacional de Genómica para la Biodiversidad (LANGEBIO), Centro de Investigación y de Estudios Avanzados del I. P. N., Irapuato, Gto 36821 Mexico
| | - Rufina Hernandez-Martinez
- Departamento de Microbiología, Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE), Ensenada, BC 22860 Mexico
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13
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Yu X, Yang J, Wang E, Li B, Yuan H. Effects of growth stage and fulvic acid on the diversity and dynamics of endophytic bacterial community in Stevia rebaudiana Bertoni leaves. Front Microbiol 2015; 6:867. [PMID: 26379644 PMCID: PMC4548236 DOI: 10.3389/fmicb.2015.00867] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Accepted: 08/10/2015] [Indexed: 01/12/2023] Open
Abstract
The aim of this study was to learn the interactions among the endophytic bacteria, the plant growth, the foliar spray of fulvic acid, and the accumulation of steviol glycosides in the leaves of Stevia rebaudiana. Metagenomic DNA was extracted from the Stevia leaves at different growth stages with or without the fulvic acid treatment; and the diversity of endophytic bacteria in Stevia leaves was estimated by pyrosequencing of 16S rRNA genes. As results, Proteobacteria, Actinobacteria, Bacteroidetes, and Firmicutes were found to be the dominant phyla despite the growth stages and fulvic acid application. Stevia growth stages strongly regulated composition of endophytic community. The genera Agrobacterium (12.3%) and Erwinia (7.2%) dominated in seedling stage were apparently declined in the vegetable and initial flowering stages, while Sphingomonas and Methylobacterium increased in mature leaves at harvest time, which showed that the mature leaves of Stevia preferred to accumulate some certain endophytic bacteria. Sphingomonas and Methylobacterium constituted an important part of the core endophytic community and were positively correlated with the stevioside content and UGT74G1 gene expression, respectively; while Erwinia, Agrobacterium, and Bacillus were negatively correlated with the stevioside accumulation. Fulvic acid treatment accelerated the variation of endophytes along the growth stages and increased the steviol glycosides content. This is the first study to reveal the community composition of endophytic bacteria in the Stevia leaves, to evidence the strong effects of growth stage and fulvic acid application on the endophytes of Stevia, and to demonstrate the correlation between the endophytic bacteria and the steviol glycosides accumulation.
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Affiliation(s)
- Xuejian Yu
- State Key Laboratory of Agrobiotechnology, MOA Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University Beijing, China
| | - Jinshui Yang
- State Key Laboratory of Agrobiotechnology, MOA Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University Beijing, China
| | - Entao Wang
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional Mexico City, Mexico
| | - Baozhen Li
- State Key Laboratory of Agrobiotechnology, MOA Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University Beijing, China
| | - Hongli Yuan
- State Key Laboratory of Agrobiotechnology, MOA Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University Beijing, China
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14
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Hobley L, Harkins C, MacPhee CE, Stanley-Wall NR. Giving structure to the biofilm matrix: an overview of individual strategies and emerging common themes. FEMS Microbiol Rev 2015; 39:649-69. [PMID: 25907113 PMCID: PMC4551309 DOI: 10.1093/femsre/fuv015] [Citation(s) in RCA: 344] [Impact Index Per Article: 38.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/09/2015] [Indexed: 01/24/2023] Open
Abstract
Biofilms are communities of microbial cells that underpin diverse processes including sewage bioremediation, plant growth promotion, chronic infections and industrial biofouling. The cells resident in the biofilm are encased within a self-produced exopolymeric matrix that commonly comprises lipids, proteins that frequently exhibit amyloid-like properties, eDNA and exopolysaccharides. This matrix fulfils a variety of functions for the community, from providing structural rigidity and protection from the external environment to controlling gene regulation and nutrient adsorption. Critical to the development of novel strategies to control biofilm infections, or the capability to capitalize on the power of biofilm formation for industrial and biotechnological uses, is an in-depth knowledge of the biofilm matrix. This is with respect to the structure of the individual components, the nature of the interactions between the molecules and the three-dimensional spatial organization. We highlight recent advances in the understanding of the structural and functional role that carbohydrates and proteins play within the biofilm matrix to provide three-dimensional architectural integrity and functionality to the biofilm community. We highlight, where relevant, experimental techniques that are allowing the boundaries of our understanding of the biofilm matrix to be extended using Escherichia coli, Staphylococcus aureus, Vibrio cholerae, and Bacillus subtilis as exemplars. Examining the structure and function of the biofilm extracellular matrix.
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Affiliation(s)
- Laura Hobley
- Division of Molecular Microbiology, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Catriona Harkins
- Division of Molecular Microbiology, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Cait E MacPhee
- James Clerk Maxwell Building, School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, UK
| | - Nicola R Stanley-Wall
- Division of Molecular Microbiology, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
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15
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Vaikuntapu PR, Dutta S, Samudrala RB, Rao VRVN, Kalam S, Podile AR. Preferential Promotion of Lycopersicon esculentum (Tomato) Growth by Plant Growth Promoting Bacteria Associated with Tomato. Indian J Microbiol 2014; 54:403-12. [PMID: 25320438 PMCID: PMC4186933 DOI: 10.1007/s12088-014-0470-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Accepted: 05/03/2014] [Indexed: 10/25/2022] Open
Abstract
A total of 74 morphologically distinct bacterial colonies were selected during isolation of bacteria from different parts of tomato plant (rhizoplane, phylloplane and rhizosphere) as well as nearby bulk soil. The isolates were screened for plant growth promoting (PGP) traits such as production of indole acetic acid, siderophore, chitinase and hydrogen cyanide as well as phosphate solubilization. Seven isolates viz., NR4, NR6, RP3, PP1, RS4, RP6 and NR1 that exhibited multiple PGP traits were identified, based on morphological, biochemical and 16S rRNA gene sequence analysis, as species that belonged to four genera Aeromonas, Pseudomonas, Bacillus and Enterobacter. All the seven isolates were positive for 1-aminocyclopropane-1-carboxylate deaminase. Isolate NR6 was antagonistic to Fusarium solani and Fusarium moniliforme, and both PP1 and RP6 isolates were antagonistic to F. moniliforme. Except RP6, all isolates adhered significantly to glass surface suggestive of biofilm formation. Seed bacterization of tomato, groundnut, sorghum and chickpea with the seven bacterial isolates resulted in varied growth response in laboratory assay on half strength Murashige and Skoog medium. Most of the tomato isolates positively influenced tomato growth. The growth response was either neutral or negative with groundnut, sorghum and chickpea. Overall, the results suggested that bacteria with PGP traits do not positively influence the growth of all plants, and certain PGP bacteria may exhibit host-specificity. Among the isolates that positively influenced growth of tomato (NR1, RP3, PP1, RS4 and RP6) only RS4 was isolated from tomato rhizosphere. Therefore, the best PGP bacteria can also be isolated from zones other than rhizosphere or rhizoplane of a plant.
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Affiliation(s)
- Papa Rao Vaikuntapu
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500 046 AP India
| | - Swarnalee Dutta
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500 046 AP India
| | - Ram Babu Samudrala
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500 046 AP India
| | - Vukanti R. V. N. Rao
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500 046 AP India
| | - Sadaf Kalam
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500 046 AP India
| | - Appa Rao Podile
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500 046 AP India
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16
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Moor H, Teppo A, Lahesaare A, Kivisaar M, Teras R. Fis overexpression enhances Pseudomonas putida biofilm formation by regulating the ratio of LapA and LapF. MICROBIOLOGY-SGM 2014; 160:2681-2693. [PMID: 25253613 DOI: 10.1099/mic.0.082503-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Bacteria form biofilm as a response to a number of environmental signals that are mediated by global transcription regulators and alarmones. Here we report the involvement of the global transcription regulator Fis in Pseudomonas putida biofilm formation through regulation of lapA and lapF genes. The major component of P. putida biofilm is proteinaceous and two large adhesive proteins, LapA and LapF, are known to play a key role in its formation. We have previously shown that Fis overexpression enhances P. putida biofilm formation. In this study, we used mini-Tn5 transposon mutagenesis to select potential Fis-regulated genes involved in biofilm formation. A total of 90 % of the studied transposon mutants carried insertions in the lap genes. Since our experiments showed that Fis-enhanced biofilm is mostly proteinaceous, the amounts of LapA and LapF from P. putida cells lysates were quantified using SDS-PAGE. Fis overexpression increases the quantity of LapA 1.6 times and decreases the amount of LapF at least 4 times compared to the wild-type cells. The increased LapA expression caused by Fis overexpression was confirmed by FACS analysis measuring the amount of LapA-GFP fusion protein. Our results suggest that the profusion of LapA in the Fis-overexpressed cells causes enhanced biofilm formation in mature stages of P. putida biofilm and LapF has a minor role in P. putida biofilm formation.
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Affiliation(s)
- Hanna Moor
- Institute of Molecular and Cell Biology, University of Tartu, Riia 23, 51010 Tartu, Estonia
| | - Annika Teppo
- Institute of Molecular and Cell Biology, University of Tartu, Riia 23, 51010 Tartu, Estonia
| | - Andrio Lahesaare
- Institute of Molecular and Cell Biology, University of Tartu, Riia 23, 51010 Tartu, Estonia
| | - Maia Kivisaar
- Institute of Molecular and Cell Biology, University of Tartu, Riia 23, 51010 Tartu, Estonia
| | - Riho Teras
- Institute of Molecular and Cell Biology, University of Tartu, Riia 23, 51010 Tartu, Estonia
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17
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Budiharjo A, Chowdhury SP, Dietel K, Beator B, Dolgova O, Fan B, Bleiss W, Ziegler J, Schmid M, Hartmann A, Borriss R. Transposon mutagenesis of the plant-associated Bacillus amyloliquefaciens ssp. plantarum FZB42 revealed that the nfrA and RBAM17410 genes are involved in plant-microbe-interactions. PLoS One 2014; 9:e98267. [PMID: 24847778 PMCID: PMC4029887 DOI: 10.1371/journal.pone.0098267] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Accepted: 04/29/2014] [Indexed: 11/18/2022] Open
Abstract
Bacillus amyloliquefaciens ssp. plantarum FZB42 represents the prototype of Gram-positive plant growth promoting and biocontrol bacteria. In this study, we applied transposon mutagenesis to generate a transposon library, which was screened for genes involved in multicellular behavior and biofilm formation on roots as a prerequisite of plant growth promoting activity. Transposon insertion sites were determined by rescue-cloning followed by DNA sequencing. As in B. subtilis, the global transcriptional regulator DegU was identified as an activator of genes necessary for swarming and biofilm formation, and the DegU-mutant of FZB42 was found impaired in efficient root colonization. Direct screening of 3,000 transposon insertion mutants for plant-growth-promotion revealed the gene products of nfrA and RBAM_017140 to be essential for beneficial effects exerted by FZB42 on plants. We analyzed the performance of GFP-labeled wild-type and transposon mutants in the colonization of lettuce roots using confocal laser scanning microscopy. While the wild-type strain heavily colonized root surfaces, the nfrA mutant did not colonize lettuce roots, although it was not impaired in growth in laboratory cultures, biofilm formation and swarming motility on agar plates. The RBAM17410 gene, occurring in only a few members of the B. subtilis species complex, was directly involved in plant growth promotion. None of the mutant strains were affected in producing the plant growth hormone auxin. We hypothesize that the nfrA gene product is essential for overcoming the stress caused by plant response towards bacterial root colonization.
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Affiliation(s)
- Anto Budiharjo
- Bakteriengenetik, Institut für Biologie, Humboldt Universität Berlin, Berlin, Germany
| | - Soumitra Paul Chowdhury
- Research Unit Microbe-Plant Interactions, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | | | - Barbara Beator
- Bakteriengenetik, Institut für Biologie, Humboldt Universität Berlin, Berlin, Germany
| | | | - Ben Fan
- Bakteriengenetik, Institut für Biologie, Humboldt Universität Berlin, Berlin, Germany
| | - Wilfrid Bleiss
- Molekulare Parasitologie, Institut für Biologie, Humboldt Universität Berlin, Berlin, Germany
| | - Jörg Ziegler
- Abteilung Molekulare Signalverarbeitung, Leibniz-Institut für Pflanzenbiochemie, Halle/Saale, Germany
| | - Michael Schmid
- Research Unit Microbe-Plant Interactions, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - Anton Hartmann
- Research Unit Microbe-Plant Interactions, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - Rainer Borriss
- Bakteriengenetik, Institut für Biologie, Humboldt Universität Berlin, Berlin, Germany
- ABiTEP GmbH, Berlin, Germany
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18
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Lo J, Lange D, Chew BH. Ureteral Stents and Foley Catheters-Associated Urinary Tract Infections: The Role of Coatings and Materials in Infection Prevention. Antibiotics (Basel) 2014; 3:87-97. [PMID: 27025736 PMCID: PMC4790349 DOI: 10.3390/antibiotics3010087] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 03/01/2014] [Accepted: 03/04/2014] [Indexed: 01/20/2023] Open
Abstract
Urinary tract infections affect many patients, especially those who are admitted to hospital and receive a bladder catheter for drainage. Catheter associated urinary tract infections are some of the most common hospital infections and cost the health care system billions of dollars. Early removal is one of the mainstays of prevention as 100% of catheters become colonized. Patients with ureteral stents are also affected by infection and antibiotic therapy alone may not be the answer. We will review the current evidence on how to prevent infections of urinary biomaterials by using different coatings, new materials, and drug eluting technologies to decrease infection rates of ureteral stents and catheters.
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Affiliation(s)
- Joey Lo
- Department of Urologic Sciences, University of British Columbia, 2660 Oak Street, Vancouver, BC, V6H 3Z6, Canada.
| | - Dirk Lange
- Department of Urologic Sciences, University of British Columbia, 2660 Oak Street, Vancouver, BC, V6H 3Z6, Canada.
| | - Ben H Chew
- Department of Urologic Sciences, University of British Columbia, 2660 Oak Street, Vancouver, BC, V6H 3Z6, Canada.
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19
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Rabe F, Ajami-Rashidi Z, Doehlemann G, Kahmann R, Djamei A. Degradation of the plant defence hormone salicylic acid by the biotrophic fungus Ustilago maydis. Mol Microbiol 2013; 89:179-88. [PMID: 23692401 DOI: 10.1111/mmi.12269] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/17/2013] [Indexed: 12/01/2022]
Abstract
Salicylic acid (SA) is a key plant defence hormone which plays an important role in local and systemic defence responses against biotrophic pathogens like the smut fungus Ustilago maydis. Here we identified Shy1, a cytoplasmic U. maydis salicylate hydroxylase which has orthologues in the closely related smuts Ustilago hordei and Sporisorium reilianum. shy1 is transcriptionally induced during the biotrophic stages of development but not required for virulence during seedling infection. Shy1 activity is needed for growth on plates with SA as a sole carbon source. The trigger for shy1 transcriptional induction is SA, suggesting the possibility of a SA sensing mechanism in this fungus.
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Affiliation(s)
- Franziska Rabe
- Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Strasse 10, D-35043, Marburg, Germany
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20
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Domingues PM, Louvado A, Oliveira V, Coelho FJCR, Almeida A, Gomes NCM, Cunha A. SELECTIVE CULTURES FOR THE ISOLATION OF BIOSURFACTANT PRODUCING BACTERIA: COMPARISON OF DIFFERENT COMBINATIONS OF ENVIRONMENTAL INOCULA AND HYDROPHOBIC CARBON SOURCES. Prep Biochem Biotechnol 2013; 43:237-55. [DOI: 10.1080/10826068.2012.719848] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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21
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Vlamakis H, Chai Y, Beauregard P, Losick R, Kolter R. Sticking together: building a biofilm the Bacillus subtilis way. Nat Rev Microbiol 2013; 11:157-68. [PMID: 23353768 DOI: 10.1038/nrmicro2960] [Citation(s) in RCA: 599] [Impact Index Per Article: 54.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Biofilms are ubiquitous communities of tightly associated bacteria encased in an extracellular matrix. Bacillus subtilis has long served as a robust model organism to examine the molecular mechanisms of biofilm formation, and a number of studies have revealed that this process is regulated by several integrated pathways. In this Review, we focus on the molecular mechanisms that control B. subtilis biofilm assembly, and then briefly summarize the current state of knowledge regarding biofilm disassembly. We also discuss recent progress that has expanded our understanding of B. subtilis biofilm formation on plant roots, which are a natural habitat for this soil bacterium.
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Affiliation(s)
- Hera Vlamakis
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts 02115, USA
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22
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Nowatzki PJ, Koepsel RR, Stoodley P, Min K, Harper A, Murata H, Donfack J, Hortelano ER, Ehrlich GD, Russell AJ. Salicylic acid-releasing polyurethane acrylate polymers as anti-biofilm urological catheter coatings. Acta Biomater 2012; 8:1869-80. [PMID: 22342353 DOI: 10.1016/j.actbio.2012.01.032] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2011] [Revised: 01/23/2012] [Accepted: 01/26/2012] [Indexed: 01/20/2023]
Abstract
Biofilm-associated infections are a major complication of implanted and indwelling medical devices like urological and venous catheters. They commonly persist even in the presence of an oral or intravenous antibiotic regimen, often resulting in chronic illness. We have developed a new approach to inhibiting biofilm growth on synthetic materials through controlled release of salicylic acid from a polymeric coating. Herein we report the synthesis and testing of a ultraviolet-cured polyurethane acrylate polymer composed, in part, of salicyl acrylate, which hydrolyzes upon exposure to aqueous conditions, releasing salicylic acid while leaving the polymer backbone intact. The salicylic acid release rate was tuned by adjusting the polymer composition. Anti-biofilm performance of the coatings was assessed under several biofilm forming conditions using a novel combination of the MBEC Assay™ biofilm multi-peg growth system and bioluminescence monitoring for live cell quantification. Films of the salicylic acid-releasing polymers were found to inhibit biofilm formation, as shown by bioluminescent and GFP reporter strains of Pseudomonas aeruginosa and Escherichia coli. Urinary catheters coated on their inner lumens with the salicylic acid-releasing polymer significantly reduced biofilm formation by E. coli for up to 5 days under conditions that simulated physiological urine flow.
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23
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Time-resolved transcriptomics and bioinformatic analyses reveal intrinsic stress responses during batch culture of Bacillus subtilis. PLoS One 2011; 6:e27160. [PMID: 22087258 PMCID: PMC3210768 DOI: 10.1371/journal.pone.0027160] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Accepted: 10/11/2011] [Indexed: 12/15/2022] Open
Abstract
We have determined the time-resolved transcriptome of the model gram-positive organism B. subtilis during growth in a batch fermentor on rich medium. DNA microarrays were used to monitor gene transcription using 10-minute intervals at 40 consecutive time points. From the growth curve and analysis of all gene expression levels, we identified 4 distinct growth phases and one clear transition point: a lag phase, an exponential growth phase, the transition point and the very clearly separated early and late stationary growth phases. The gene expression profiles suggest the occurrence of stress responses at specific times although no external stresses were applied. The first one is a small induction of the SigB regulon that occurs at the transition point. Remarkably, a very strong response is observed for the SigW regulon, which is highly upregulated at the onset of the late stationary phase. Bioinformatic analyses that were performed on our data set suggest several novel putative motifs for regulator binding. In addition, the expression profiles of several genes appeared to correlate with the oxygen concentration. This data set of the expression profiles of all B. subtilis genes during the entire growth curve on rich medium constitutes a rich repository that can be further mined by the scientific community.
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24
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Huang B, Lv C, Zhuang P, Zhang H, Fan L. Endophytic colonisation of Bacillus subtilis in the roots of Robinia pseudoacacia L. PLANT BIOLOGY (STUTTGART, GERMANY) 2011; 13:925-31. [PMID: 21972966 DOI: 10.1111/j.1438-8677.2011.00456.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The endophytic colonisation of Bacillus subtilis strain GXJM08, isolated from roots of Podocarpus imbricatus B1. Enum. P1. Jav., in roots of the leguminous plant Robinia pseudoacacia L. was investigated. Ultrastructure observations showed that B. subtilis caused morphological changes in the root hair and colonised the plant through infected root hairs. The structure of the infection thread was similar to that of rhizobia, but the structure of infected cells was different. B. subtilis is also different from rhizobia and plant pathogens in terms of the formation of a peribacteroid membrane and the mode of penetration through the host cell wall. Our results provide a basis for studying development of the mutualistic symbiotic relationship between B. subtilis and plants, and a basis for studying the mechanism of the B. subtilis-plant interaction.
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Affiliation(s)
- B Huang
- College of Forestry, Guangxi University, Nanning, Guangxi, China.
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25
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Stark JL, Mercier KA, Mueller GA, Acton TB, Xiao R, Montelione GT, Powers R. Solution structure and function of YndB, an AHSA1 protein from Bacillus subtilis. Proteins 2011; 78:3328-40. [PMID: 20818668 DOI: 10.1002/prot.22840] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The solution structure of the Bacillus subtilis protein YndB has been solved using NMR to investigate proposed biological functions. The YndB structure exhibits the helix-grip fold, which consists of a β-sheet with two small and one long α-helix, forming a hydrophobic cavity that preferentially binds lipid-like molecules. Sequence and structure comparisons with proteins from eukaryotes, prokaryotes, and archaea suggest that YndB is very similar to the eukaryote protein Aha1, which binds to the middle domain of Hsp90 and induces ATPase activity. On the basis of these similarities, YndB has been classified as a member of the activator of Hsp90 ATPase homolog 1-like protein (AHSA1) family with a function that appears to be related to stress response. An in silico screen of a compound library of ∼ 18,500 lipids was used to identify classes of lipids that preferentially bind YndB. The in silico screen identified, in order of affinity, the chalcone/hydroxychalcone, flavanone, and flavone/flavonol classes of lipids, which was further verified by 2D (1) H-(15) N HSQC NMR titration experiments with trans-chalcone, flavanone, flavone, and flavonol. All of these compounds are typically found in plants as precursors to various flavonoid antibiotics and signaling molecules. The sum of the data suggests an involvement of YndB with the stress response of B. subtilis to chalcone-like flavonoids released by plants due to a pathogen infection. The observed binding of chalcone-like molecules by YndB is likely related to the symbiotic relationship between B. subtilis and plants.
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Affiliation(s)
- Jaime L Stark
- Department of Chemistry, University of Nebraska Lincoln, Lincoln, Nebraska 68588-0304, USA
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26
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Matilla MA, Ramos JL, Bakker PAHM, Doornbos R, Badri DV, Vivanco JM, Ramos-González MI. Pseudomonas putida KT2440 causes induced systemic resistance and changes in Arabidopsis root exudation. ENVIRONMENTAL MICROBIOLOGY REPORTS 2010; 2:381-8. [PMID: 23766110 DOI: 10.1111/j.1758-2229.2009.00091.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Pseudomonas putida KT2440 is an efficient colonizer of the rhizosphere of plants of agronomical and basic interest. We have demonstrated that KT2440 can protect the model plant Arabidopsis thaliana against infection by the phytopathogen Pseudomonas syringae pv. tomato DC3000. P. putida extracellular haem-peroxidase (PP2561) was found to be important for competitive colonization and essential for the induction of plant systemic resistance. Root exudates of plants elicited by KT2440 exhibited distinct patterns of metabolites compared with those of non-elicited plants. The levels of some of these compounds were dramatically reduced in axenic plants or plants colonized by a mutant defective in PP2561, which has increased sensitiveness to oxidative stress with respect to the wild type. Thus high-level oxidative stress resistance is a bacterial driving force in the rhizosphere for efficient colonization and to induce systemic resistance. These results provide important new insight into the complex events that occur in order for plants to attain resistance against foliar pathogens.
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Affiliation(s)
- Miguel A Matilla
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Profesor Albareda 1, Granada 18008, Spain. Plant-Microbe Interactions, Department of Biology, Utrecht University, The Netherlands. Department of Horticulture and Landscape Architecture, Colorado State University, 217 Shepardson Building, Fort Collins, CO 80523, USA
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Rudrappa T, Biedrzycki ML, Kunjeti SG, Donofrio NM, Czymmek KJ, Paré PW, Bais HP. The rhizobacterial elicitor acetoin induces systemic resistance in Arabidopsis thaliana. Commun Integr Biol 2010; 3:130-8. [PMID: 20585504 PMCID: PMC2889968 DOI: 10.4161/cib.3.2.10584] [Citation(s) in RCA: 128] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2009] [Revised: 11/09/2009] [Accepted: 11/09/2009] [Indexed: 01/09/2023] Open
Abstract
The majority of plant growth promoting rhizobacteria (PGPR) confer plant immunity against a wide range of foliar diseases by activating plant defences that reduce a plant's susceptibility to pathogen attack. Here we show that Arabidopsis thaliana (Col-0) plants exposed to Bacillus subtilis strain FB17 (hereafter FB17), results in reduced disease severity against Pseudomonas syringae pv. tomato DC3000 (hereafter DC3000) compared to plants without FB17 treatment. Exogenous application of the B. subtilis derived elicitor, acetoin (3-hydroxy-2-butanone), was found to trigger induced systemic resistance (ISR) and protect plants against DC3000 pathogenesis. Moreover, B. subtilis acetoin biosynthetic mutants that emitted reduced levels of acetoin conferred reduced protection to A. thaliana against pathogen infection. Further analysis using FB17 and defense-compromised mutants of A. thaliana indicated that resistance to DC3000 occurs via NPR1 and requires salicylic acid (SA)/ethylene (ET) whereas jasmonic acid (JA) is not essential. This study provides new insight into the role of rhizo-bacterial volatile components as elicitors of defense responses in plants.
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Micallef SA, Shiaris MP, Colón-Carmona A. Influence of Arabidopsis thaliana accessions on rhizobacterial communities and natural variation in root exudates. JOURNAL OF EXPERIMENTAL BOTANY 2009; 60:1729-42. [PMID: 19342429 PMCID: PMC2671628 DOI: 10.1093/jxb/erp053] [Citation(s) in RCA: 218] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2008] [Accepted: 02/03/2009] [Indexed: 05/18/2023]
Abstract
Plant species is considered to be one of the most important factors in shaping rhizobacterial communities, but specific plant-microbe interactions in the rhizosphere are still not fully understood. Arabidopsis thaliana, for which a large number of naturally occurring ecotype accessions exist, lacks mycorrhizal associations and is hence an ideal model for rhizobacterial studies. Eight Arabidopsis accessions were found to exert a marked selective influence on bacteria associated with their roots, as determined by terminal-restriction fragment length polymorphism (T-RFLP) and ribosomal intergenic spacer analysis (RISA). Community differences in species composition and relative abundance were both significant (P <0.001). The eight distinct and reproducible accession-dependent community profiles also differed from control bulk soil. Root exudates of these variants were analysed by high performance liquid chromatography (HPLC) to try to establish whether the unique rhizobacterial assemblages among accessions could be attributed to plant-regulated chemical changes in the rhizosphere. Natural variation in root exudation patterns was clearly exhibited, suggesting that differences in exudation patterns among accessions could be influencing bacterial assemblages. Other factors such as root system architecture are also probably involved. Finally, to investigate the Arabidopsis rhizosphere further, the phylogenetic diversity of rhizobacteria from accession Cvi-0 is described.
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Affiliation(s)
| | | | - Adán Colón-Carmona
- Department of Biology, University of Massachusetts Boston, 100 Morrissey Boulevard, Boston, MA 02125, USA
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Li SM, Hua GG, Liu HX, Guo JH. Analysis of defence enzymes induced by antagonistic bacteriumBacillus subtilis strain AR12 towardsRalstonia solanacearum in tomato. ANN MICROBIOL 2008. [DOI: 10.1007/bf03175560] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Rudrappa T, Bais HP. Rhizospheric pseudomonads: Friends or foes? PLANT SIGNALING & BEHAVIOR 2008; 3:1132-1133. [PMID: 19704457 PMCID: PMC2634478 DOI: 10.4161/psb.3.12.7093] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2008] [Accepted: 10/01/2008] [Indexed: 05/28/2023]
Abstract
Of the different groups of soil microorganisms, pseudomonads are one of the important class, playing various roles in the plants growth and development. Although they have been reported to inflict both beneficial and harmful effect on plants, they act through various mechanisms. Among the different mechanisms, cyanogenesis is one of the important factors used by pseudomonads to cause positive and less studied negative effects in the rhizosphere. By employing a bioassay driven approach, we dissected the direct effect of pseudomonad cyanogenesis on host plants and also its indirect effect through the inhibition of beneficial biofilm formation by B. subtilis. This study may further our understanding on the multi-tropic rhizospheric interactions mediated by rhizospheric pseudomonads.
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Affiliation(s)
- Thimmaraju Rudrappa
- Department of Plant and Soil Sciences; Delaware Biotechnology Institute; Newark, Delaware USA
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Rudrappa T, Czymmek KJ, Paré PW, Bais HP. Root-secreted malic acid recruits beneficial soil bacteria. PLANT PHYSIOLOGY 2008; 148:1547-56. [PMID: 18820082 PMCID: PMC2577262 DOI: 10.1104/pp.108.127613] [Citation(s) in RCA: 479] [Impact Index Per Article: 29.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Beneficial soil bacteria confer immunity against a wide range of foliar diseases by activating plant defenses, thereby reducing a plant's susceptibility to pathogen attack. Although bacterial signals have been identified that activate these plant defenses, plant metabolites that elicit rhizobacterial responses have not been demonstrated. Here, we provide biochemical evidence that the tricarboxylic acid cycle intermediate L-malic acid (MA) secreted from roots of Arabidopsis (Arabidopsis thaliana) selectively signals and recruits the beneficial rhizobacterium Bacillus subtilis FB17 in a dose-dependent manner. Root secretions of L-MA are induced by the foliar pathogen Pseudomonas syringae pv tomato (Pst DC3000) and elevated levels of L-MA promote binding and biofilm formation of FB17 on Arabidopsis roots. The demonstration that roots selectively secrete L-MA and effectively signal beneficial rhizobacteria establishes a regulatory role of root metabolites in recruitment of beneficial microbes, as well as underscores the breadth and sophistication of plant-microbial interactions.
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Affiliation(s)
- Thimmaraju Rudrappa
- Department of Plant and Soil Sciences, University of Delaware, Newark, Delaware 19716, USA
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32
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Earl AM, Losick R, Kolter R. Ecology and genomics of Bacillus subtilis. Trends Microbiol 2008; 16:269-75. [PMID: 18467096 DOI: 10.1016/j.tim.2008.03.004] [Citation(s) in RCA: 272] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2007] [Revised: 03/27/2008] [Accepted: 03/28/2008] [Indexed: 01/26/2023]
Abstract
Bacillus subtilis is a remarkably diverse bacterial species that is capable of growth within many environments. Recent microarray-based comparative genomic analyses have revealed that members of this species also exhibit considerable genomic diversity. The identification of strain-specific genes might explain how B. subtilis has become so broadly adapted. The goal of identifying ecologically adaptive genes could soon be realized with the imminent release of several new B. subtilis genome sequences. As we embark upon this exciting new era of B. subtilis comparative genomics we review what is currently known about the ecology and evolution of this species.
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Affiliation(s)
- Ashlee M Earl
- Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, MA 02115, USA
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Rudrappa T, Splaine RE, Biedrzycki ML, Bais HP. Cyanogenic pseudomonads influence multitrophic interactions in the rhizosphere. PLoS One 2008; 3:e2073. [PMID: 18446201 PMCID: PMC2315799 DOI: 10.1371/journal.pone.0002073] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2008] [Accepted: 03/21/2008] [Indexed: 11/18/2022] Open
Abstract
In the rhizosphere, plant roots cope with both pathogenic and beneficial bacterial interactions. The exometabolite production in certain bacterial species may regulate root growth and other root-microbe interactions in the rhizosphere. Here, we elucidated the role of cyanide production in pseudomonad virulence affecting plant root growth and other rhizospheric processes. Exposure of Arabidopsis thaliana Col-0 seedlings to both direct (with KCN) and indirect forms of cyanide from different pseudomonad strains caused significant inhibition of primary root growth. Further, we report that this growth inhibition was caused by the suppression of an auxin responsive gene, specifically at the root tip region by pseudomonad cyanogenesis. Additionally, pseudomonad cyanogenesis also affected other beneficial rhizospheric processes such as Bacillus subtilis colonization by biofilm formation on A. thaliana Col-0 roots. The effect of cyanogenesis on B. subtilis biofilm formation was further established by the down regulation of important B. subtilis biofilm operons epsA and yqxM. Our results show, the functional significance of pseudomonad cyanogenesis in regulating multitrophic rhizospheric interactions.
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Affiliation(s)
- Thimmaraju Rudrappa
- Department of Plant and Soil Sciences, University of Delaware, Newark, Delaware, United States of America
- Delaware Biotechnology Institute, Newark, Delaware, United States of America
| | - Robert E. Splaine
- Department of Plant and Soil Sciences, University of Delaware, Newark, Delaware, United States of America
- Delaware Biotechnology Institute, Newark, Delaware, United States of America
| | - Meredith L. Biedrzycki
- Department of Plant and Soil Sciences, University of Delaware, Newark, Delaware, United States of America
- Delaware Biotechnology Institute, Newark, Delaware, United States of America
| | - Harsh P. Bais
- Department of Plant and Soil Sciences, University of Delaware, Newark, Delaware, United States of America
- Delaware Biotechnology Institute, Newark, Delaware, United States of America
- * E-mail:
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Rudrappa T, Biedrzycki ML, Bais HP. Causes and consequences of plant-associated biofilms. FEMS Microbiol Ecol 2008; 64:153-66. [PMID: 18355294 DOI: 10.1111/j.1574-6941.2008.00465.x] [Citation(s) in RCA: 139] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The rhizosphere is the critical interface between plant roots and soil where beneficial and harmful interactions between plants and microorganisms occur. Although microorganisms have historically been studied as planktonic (or free-swimming) cells, most are found attached to surfaces, in multicellular assemblies known as biofilms. When found in association with plants, certain bacteria such as plant growth promoting rhizobacteria not only induce plant growth but also protect plants from soil-borne pathogens in a process known as biocontrol. Contrastingly, other rhizobacteria in a biofilm matrix may cause pathogenesis in plants. Although research suggests that biofilm formation on plants is associated with biological control and pathogenic response, little is known about how plants regulate this association. Here, we assess the biological importance of biofilm association on plants.
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Affiliation(s)
- Thimmaraju Rudrappa
- Department of Plant and Soil Sciences, University of Delaware, Newark, DE 19711, USA
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Rudrappa T, Bais HP. Arabidopsis thaliana Root Surface Chemistry Regulates in Planta Biofilm Formation of Bacillus subtilis. PLANT SIGNALING & BEHAVIOR 2007; 2:349-50. [PMID: 19704655 PMCID: PMC2634208 DOI: 10.4161/psb.2.5.4117] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2007] [Accepted: 03/07/2007] [Indexed: 05/15/2023]
Abstract
Among the various rhizospheric interactions, plant root-microbe interactions are very important both economically and ecologically. The interaction of plant roots with plant growth promoting rhizobacteria (PGPR) have been studied in case of symbiotic organisms. However, the knowledge on interaction with other PGPRs such as biocontrol Bacillus sps. is vastly unexplored. Especially the complex root surface chemistry and its effect on modulating the bacterial growth and association with the root system has not been investigated. Recently, by adopting a systematic stepwise experimental approach we unraveled the importance of root plane chemistry on the colonization and biofilm formation by B. subtilis, an important biocontrol-PGPR. This study may further increase our understanding in the field of rhizosphere biology and area of root secretions and their possible role in plant microbe interactions.
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Affiliation(s)
- Thimmaraju Rudrappa
- Department of Plant and Soil Sciences; Delaware Biotechnology Institute; Newark, Delaware USA
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