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Thomas VE, Antony-Babu S. Core hyphosphere microbiota of Fusarium oxysporum f. sp. niveum. ENVIRONMENTAL MICROBIOME 2024; 19:14. [PMID: 38461269 PMCID: PMC10924372 DOI: 10.1186/s40793-024-00558-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 02/22/2024] [Indexed: 03/11/2024]
Abstract
BACKGROUND Bacteria and fungi are dynamically interconnected, leading to beneficial or antagonistic relationships with plants. Within this interkingdom interaction, the microbial community directly associated with the pathogen make up the pathobiome. While the overall soil bacterial community associated with Fusarium wilt diseases has been widely examined, the specific bacterial populations that directly interact with the Fusarium wilt pathogens are yet to be discovered. In this study, we define the bacterial community associated with the hyphae of Fusarium oxysporum f. sp. niveum race 2 (FON2). Using the 16S rRNA gene metabarcoding, we describe the hyphosphere pathobiome of three isolates of FON2. RESULTS Our results show a core microbiome that is shared among the three tested hyphospheres. The core hyphosphere community was made up of 15 OTUs (Operational Taxonomic Units) that were associated with all three FON2 isolates. This core consisted of bacterial members of the families, Oxalobacteraceae, Propionibacteriaceae, Burkholderiaceae, Micrococcaceae, Bacillaceae, Comamonadaceae, Pseudomonadaceae and unclassified bacteria. The hyphosphere of FON2 was dominated by order Burkholderiales. While all three isolate hyphospheres were dominated by these taxa, the specific OTU differed. We also note that while the dominant OTU of one hyphosphere might not be the largest OTU for other hyphospheres, they were still present across all the three isolate hyphospheres. Additionally, in the correlation and co-occurrence analysis the most abundant OTU was negatively correlated with most of the other OTU populations within the hyphosphere. CONCLUSIONS The study indicates a core microbiota associated with FON2. These results provide insights into the microbe-microbe dynamic of the pathogen's success and its ability to recruit a core pathobiome. Our research promotes the concept of pathogens not being lone invaders but recruits from the established host microbiome to form a pathobiome.
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Affiliation(s)
- Vanessa E Thomas
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX, 77843, USA
| | - Sanjay Antony-Babu
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX, 77843, USA.
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2
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Rutkowska N, Drożdżyński P, Ryngajłło M, Marchut-Mikołajczyk O. Plants as the Extended Phenotype of Endophytes-The Actual Source of Bioactive Compounds. Int J Mol Sci 2023; 24:10096. [PMID: 37373241 DOI: 10.3390/ijms241210096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 06/07/2023] [Accepted: 06/12/2023] [Indexed: 06/29/2023] Open
Abstract
For thousands of years, plants have been used for their medicinal properties. The industrial production of plant-beneficial compounds is facing many drawbacks, such as seasonal dependence and troublesome extraction and purification processes, which have led to many species being on the edge of extinction. As the demand for compounds applicable to, e.g., cancer treatment, is still growing, there is a need to develop sustainable production processes. The industrial potential of the endophytic microorganisms residing within plant tissues is undeniable, as they are often able to produce, in vitro, similar to or even the same compounds as their hosts. The peculiar conditions of the endophytic lifestyle raise questions about the molecular background of the biosynthesis of these bioactive compounds in planta, and the actual producer, whether it is the plant itself or its residents. Extending this knowledge is crucial to overcoming the current limitations in the implementation of endophytes for larger-scale production. In this review, we focus on the possible routes of the synthesis of host-specific compounds in planta by their endophytes.
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Affiliation(s)
- Natalia Rutkowska
- Institute of Molecular and Industrial Biotechnology, Lodz University of Technology, Stefanowskiego 2/22, 90-537 Lodz, Poland
| | - Piotr Drożdżyński
- Institute of Molecular and Industrial Biotechnology, Lodz University of Technology, Stefanowskiego 2/22, 90-537 Lodz, Poland
| | - Małgorzata Ryngajłło
- Institute of Molecular and Industrial Biotechnology, Lodz University of Technology, Stefanowskiego 2/22, 90-537 Lodz, Poland
| | - Olga Marchut-Mikołajczyk
- Institute of Molecular and Industrial Biotechnology, Lodz University of Technology, Stefanowskiego 2/22, 90-537 Lodz, Poland
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3
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Basiru S, Ait Si Mhand K, Hijri M. Disentangling arbuscular mycorrhizal fungi and bacteria at the soil-root interface. MYCORRHIZA 2023; 33:119-137. [PMID: 36961605 DOI: 10.1007/s00572-023-01107-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 02/21/2023] [Indexed: 06/08/2023]
Abstract
Arbuscular mycorrhizal fungi (AMF) are essential components of the plant root mycobiome and are found in approximately 80% of land plants. As obligate plant symbionts, AMF harbor their own microbiota, both inside and outside the plant root system. AMF-associated bacteria (AAB) possess various functional traits, including nitrogen fixation, organic and inorganic phosphate mobilization, growth hormone production, biofilm production, enzymatic capabilities, and biocontrol against pathogen attacks, which not only contribute to the health of the arbuscular mycorrhizal symbiosis but also promote plant growth. Because of this, there is increasing interest in the diversity, functioning, and mechanisms that underlie the complex interactions between AMF, AAB, and plant hosts. This review critically examines AMF-associated bacteria, focusing on AAB diversity, the factors driving richness and community composition of these bacteria across various ecosystems, along with the physical, chemical, and biological connections that enable AMF to select and recruit beneficial bacterial symbionts on and within their structures and hyphospheres. Additionally, potential applications of these bacteria in agriculture are discussed, emphasizing the potential importance of AMF fungal highways in engineering plant rhizosphere and endophyte bacteria communities, and the importance of a functional core of AAB taxa as a promising tool to improve plant and soil productivity. Thus, AMF and their highly diverse bacterial taxa represent important tools that could be efficiently explored in sustainable agriculture, carbon sequestration, and reduction of greenhouse gas emissions related to nitrogen fertilizer applications. Nevertheless, future studies adopting integrated multidisciplinary approaches are crucial to better understand AAB functional diversity and the mechanisms that govern these tripartite relationships.
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Affiliation(s)
- Sulaimon Basiru
- African Genome Center, Mohammed VI Polytechnic University (UM6P), Lot 660, Hay Moulay Rachid, Ben Guerir, 43150, Morocco
| | - Khadija Ait Si Mhand
- African Genome Center, Mohammed VI Polytechnic University (UM6P), Lot 660, Hay Moulay Rachid, Ben Guerir, 43150, Morocco
| | - Mohamed Hijri
- African Genome Center, Mohammed VI Polytechnic University (UM6P), Lot 660, Hay Moulay Rachid, Ben Guerir, 43150, Morocco.
- Institut de recherche en biologie végétale (IRBV), Département de Sciences Biologiques, Université de Montréal, QC, Montréal, Canada.
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4
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Zhou ZY, Liu X, Cui JL, Wang JH, Wang ML, Zhang G. Endophytic fungi and their bioactive secondary metabolites in medicinal leguminosae plants: Nearly untapped medical resources. FEMS Microbiol Lett 2022; 369:6615458. [PMID: 35746878 DOI: 10.1093/femsle/fnac052] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 06/07/2022] [Indexed: 11/12/2022] Open
Abstract
There are many species of Chinese traditional leguminosae family plants that are well known for their medicinal applications, such as Astragalus membranaceus, Catsia tora, Glycyrrhiza uralensis, Sophora flavescens and Albacia acacia. Their unique bioactive composition and internal phenological environment contribute to the formation of specific and unique endophytic fungal communities, which are important resources for new compounds used in a variety of pharmacological activities. Nonetheless, they have not been systematically studied. In the last decade, nearly 64 genera and thousands of species of endophytic fungi have been discovered from leguminosae plants, as well as 138 secondary metabolites (with 34 new compounds) including flavonoid, alkaloids, phenol, anthraquinone, macrolide, terpenoid, phytohormone and many more. They were shown to have diverse applications and benefits, such as antibacterial, antitumor, antioxidative, immunoregulatory and neuroprotective properties. Here, we provide a summarized overview with the aim of raising awareness of endophytic fungi from medicinal leguminosae plants and providing a comprehensive review of the discoveries of new natural products that may be of medicinal and pharmaceutical importance.
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Affiliation(s)
- Zhong-Ya Zhou
- Institute of Applied Chemistry, Shanxi University, Taiyuan, Shanxi 030006, People's Republic of China.,Modern Research Center for Traditional Chinese Medicine, the Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Shanxi University, Taiyuan, Shanxi 030006, People's Republic of China
| | - Xi Liu
- Institute of Applied Chemistry, Shanxi University, Taiyuan, Shanxi 030006, People's Republic of China.,Modern Research Center for Traditional Chinese Medicine, the Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Shanxi University, Taiyuan, Shanxi 030006, People's Republic of China
| | - Jin-Long Cui
- Institute of Applied Chemistry, Shanxi University, Taiyuan, Shanxi 030006, People's Republic of China
| | - Jun-Hong Wang
- Institute of Applied Chemistry, Shanxi University, Taiyuan, Shanxi 030006, People's Republic of China
| | - Meng-Liang Wang
- Institute of Applied Chemistry, Shanxi University, Taiyuan, Shanxi 030006, People's Republic of China
| | - Gang Zhang
- College of Pharmacy, Shaanxi University of Chinese Medicine, Century Avenue, Xianyang 712046, China
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Cheng S, Jiang JW, Tan LT, Deng JX, Liang PY, Su H, Sun ZX, Zhou Y. Plant Growth-Promoting Ability of Mycorrhizal Fusarium Strain KB-3 Enhanced by Its IAA Producing Endohyphal Bacterium, Klebsiella aerogenes. Front Microbiol 2022; 13:855399. [PMID: 35495715 PMCID: PMC9051524 DOI: 10.3389/fmicb.2022.855399] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Accepted: 03/15/2022] [Indexed: 11/29/2022] Open
Abstract
Fusarium oxysporum KB-3 had been reported as a mycorrhizal fungus of Bletilla striata, which can promote the seed germination and vegetative growth. Endohyphal bacteria were demonstrated in the hyphae of the KB-3 by 16S rDNA PCR amplification and SYTO-9 fluorescent nucleic acid staining. A strain Klebsiella aerogenes KE-1 was isolated and identified based on the multilocus sequence analysis. The endohyphal bacterium was successfully removed from the wild strain KB-3 (KB-3−), and GFP-labeled KE-1 was also transferred to the cured strain KB-3− (KB-3+). The production of indole-3-acetic acid (IAA) in the culturing broths of strains of KE-1, KB-3, KB-3−, and KB-3+ was examined by HPLC. Their IAA productions were estimated using Salkowski colorimetric technique. The highest concentrations of IAA were 76.9 (at 48 h after inoculation), 31.4, 9.6, and 19.4 μg/ml (at 60 h after inoculation), respectively. Similarly, the three fungal cultural broths exhibited plant promoting abilities on the tomato root and stem growth. The results indicated that the ability of mycorrhizal Fusarium strain KB-3 to promote plant growth was enhanced because its endohyphal bacterium, Klebsiella aerogenes KE-1, produced a certain amount of IAA.
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Del Frari G, Ferreira RB. Microbial Blends: Terminology Overview and Introduction of the Neologism "Skopobiota". Front Microbiol 2021; 12:659592. [PMID: 34276594 PMCID: PMC8283781 DOI: 10.3389/fmicb.2021.659592] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 06/07/2021] [Indexed: 11/30/2022] Open
Affiliation(s)
- Giovanni Del Frari
- LEAF-Linking Landscape, Environment, Agriculture and Food-Research Center, Instituto Superior de Agronomia, Universidade de Lisboa, Lisbon, Portugal
| | - Ricardo Boavida Ferreira
- LEAF-Linking Landscape, Environment, Agriculture and Food-Research Center, Instituto Superior de Agronomia, Universidade de Lisboa, Lisbon, Portugal
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Aghdam SA, Brown AMV. Deep learning approaches for natural product discovery from plant endophytic microbiomes. ENVIRONMENTAL MICROBIOME 2021; 16:6. [PMID: 33758794 PMCID: PMC7972023 DOI: 10.1186/s40793-021-00375-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 02/21/2021] [Indexed: 05/10/2023]
Abstract
Plant microbiomes are not only diverse, but also appear to host a vast pool of secondary metabolites holding great promise for bioactive natural products and drug discovery. Yet, most microbes within plants appear to be uncultivable, and for those that can be cultivated, their metabolic potential lies largely hidden through regulatory silencing of biosynthetic genes. The recent explosion of powerful interdisciplinary approaches, including multi-omics methods to address multi-trophic interactions and artificial intelligence-based computational approaches to infer distribution of function, together present a paradigm shift in high-throughput approaches to natural product discovery from plant-associated microbes. Arguably, the key to characterizing and harnessing this biochemical capacity depends on a novel, systematic approach to characterize the triggers that turn on secondary metabolite biosynthesis through molecular or genetic signals from the host plant, members of the rich 'in planta' community, or from the environment. This review explores breakthrough approaches for natural product discovery from plant microbiomes, emphasizing the promise of deep learning as a tool for endophyte bioprospecting, endophyte biochemical novelty prediction, and endophyte regulatory control. It concludes with a proposed pipeline to harness global databases (genomic, metabolomic, regulomic, and chemical) to uncover and unsilence desirable natural products. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1186/s40793-021-00375-0.
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Affiliation(s)
- Shiva Abdollahi Aghdam
- Department of Biological Sciences, Texas Tech University, 2901 Main St, Lubbock, TX 79409 USA
| | - Amanda May Vivian Brown
- Department of Biological Sciences, Texas Tech University, 2901 Main St, Lubbock, TX 79409 USA
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Arora P, Kumar A, A Vishwakarma R, Riyaz-Ul-Hassan S. A natural association of a yeast with Aspergillus terreus and its impact on the host fungal biology. FEMS Microbiol Lett 2021; 368:6169704. [PMID: 33713123 DOI: 10.1093/femsle/fnab032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 03/10/2021] [Indexed: 12/27/2022] Open
Abstract
Several fungi have been shown to harbor microorganisms that regulate the key components of fungal metabolism. We explored the symbiotic association of an endophyte, Aspergillus terreus, which led to the isolation of a yeast, Meyerozyma caribbica, as its symbiont. An axenic fungal culture, free of the symbiont, was developed to study the effect of this association on the endophytic fungus. The symbiotic yeast partner was found to play an important role in the adaptation of A. terreus to thermal as well as osmotic stress. Under these stress conditions, the symbiont enhanced the production of lovastatin and the growth of the host fungus. The symbiotic yeast was found to induce the expression of the global regulator gene, the key genes involved in the lovastatin biosynthetic pathway as well as those involved in general growth and development, under stress conditions, in the fungal partner. Analysis by PCR and fluorescent in situ hybridization microscopy indicated that the yeast may be present inside the hyphae of the fungus. However, a direct method like transmission electron microscopy may help to better understand the dynamics of this association, including the distribution of the yeast cells in/on the fungal hyphae and spores.
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Affiliation(s)
- Palak Arora
- Microbial Biotechnology Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, Jammu and Kashmir 180001, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Amit Kumar
- Instrumentation Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, Jammu and Kashmir 180001, India
| | - Ram A Vishwakarma
- Microbial Biotechnology Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, Jammu and Kashmir 180001, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Syed Riyaz-Ul-Hassan
- Microbial Biotechnology Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, Jammu and Kashmir 180001, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
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10
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Rudgers JA, Afkhami ME, Bell-Dereske L, Chung YA, Crawford KM, Kivlin SN, Mann MA, Nuñez MA. Climate Disruption of Plant-Microbe Interactions. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2020. [DOI: 10.1146/annurev-ecolsys-011720-090819] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Interactions between plants and microbes have important influences on evolutionary processes, population dynamics, community structure, and ecosystem function. We review the literature to document how climate change may disrupt these ecological interactions and develop a conceptual framework to integrate the pathways of plant-microbe responses to climate over different scales in space and time. We then create a blueprint to aid generalization that categorizes climate effects into changes in the context dependency of plant-microbe pairs, temporal mismatches and altered feedbacks over time, or spatial mismatches that accompany species range shifts. We pair a new graphical model of how plant-microbe interactions influence resistance to climate change with a statistical approach to predictthe consequences of increasing variability in climate. Finally, we suggest pathways through which plant-microbe interactions can affect resilience during recovery from climate disruption. Throughout, we take a forward-looking perspective, highlighting knowledge gaps and directions for future research.
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Affiliation(s)
- Jennifer A. Rudgers
- Department of Biology, University of New Mexico, Albuquerque, New Mexico 87131, USA;,
| | - Michelle E. Afkhami
- Department of Biology, University of Miami, Coral Gables, Florida 33157, USA
| | - Lukas Bell-Dereske
- Kellogg Biological Station, Michigan State University, Hickory Corners, Michigan 49060, USA
| | - Y. Anny Chung
- Departments of Plant Biology and Plant Pathology, University of Georgia, Athens, Georgia 30602, USA
| | - Kerri M. Crawford
- Department of Biology and Biochemistry, University of Houston, Houston, Texas 77204, USA
| | - Stephanie N. Kivlin
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Michael A. Mann
- Department of Biology, University of New Mexico, Albuquerque, New Mexico 87131, USA;,
| | - Martin A. Nuñez
- Grupo de Ecología de Invasiones, Instituto de Investigaciones en Biodiversidad y Medioambiente, CONICET/Universidad Nacional del Comahue, Bariloche 8400, Argentina
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Bastías DA, Johnson LJ, Card SD. Symbiotic bacteria of plant-associated fungi: friends or foes? CURRENT OPINION IN PLANT BIOLOGY 2020; 56:1-8. [PMID: 31786411 DOI: 10.1016/j.pbi.2019.10.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 10/21/2019] [Accepted: 10/30/2019] [Indexed: 06/10/2023]
Abstract
Many bacteria form symbiotic associations with plant-associated fungi. The effects of these symbionts on host fitness usually depend on symbiont or host genotypes and environmental conditions. However, bacterial endosymbionts, that is those living within fungal cells, may positively regulate host performance as their survival is often heavily dependent on host fitness. Contrary to this, bacteria that establish ectosymbiotic associations with fungi, that is those located on the hyphal surface or in close vicinity to fungal mycelia, may not have an apparent net effect on fungal performance due to the low level of fitness dependency on their host. Our analysis supports the hypothesis that endosymbiotic bacteria of fungi are beneficial symbionts, and that effects of ectosymbiotic bacteria on fungal performance depends on the bacterial type involved in the interaction (e.g. helper versus pathogen of fungi). Ecological scenarios, where the presence of beneficial bacterial endosymbionts of fungi could be compromised, are also discussed.
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Affiliation(s)
- Daniel A Bastías
- Forage Science, AgResearch Limited, Grasslands Research Centre, Palmerston North, New Zealand.
| | - Linda J Johnson
- Forage Science, AgResearch Limited, Grasslands Research Centre, Palmerston North, New Zealand
| | - Stuart D Card
- Forage Science, AgResearch Limited, Grasslands Research Centre, Palmerston North, New Zealand
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A TAL effector-like protein of an endofungal bacterium increases the stress tolerance and alters the transcriptome of the host. Proc Natl Acad Sci U S A 2020; 117:17122-17129. [PMID: 32632014 PMCID: PMC7382252 DOI: 10.1073/pnas.2003857117] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Endosymbiotic bacteria are found in diverse fungi, but little is known about how they communicate with their hosts. Some plant pathogenic bacteria use type III-translocated TAL effectors to control host transcription, and TAL-like proteins are encoded in genomes of the fungal endosymbiotic bacterium Mycetohabitans rhizoxinica. In this paper, we present evidence that these proteins are, like TAL effectors, type III-secreted, nuclear-localizing effectors that perturb host transcription and show that one enhances tolerance of the fungal host to cell membrane stress. Our characterization of an effector in a bacterial–fungal symbiosis opens a new door to molecular understanding of these interkingdom partnerships. Our findings also provide insight into the functional diversity and evolution of the TAL effector protein family. Symbioses of bacteria with fungi have only recently been described and are poorly understood. In the symbiosis of Mycetohabitans (formerly Burkholderia) rhizoxinica with the fungus Rhizopus microsporus, bacterial type III (T3) secretion is known to be essential. Proteins resembling T3-secreted transcription activator-like (TAL) effectors of plant pathogenic bacteria are encoded in the three sequenced Mycetohabitans spp. genomes. TAL effectors nuclear-localize in plants, where they bind and activate genes important in disease. The Burkholderia TAL-like (Btl) proteins bind DNA but lack the N- and C-terminal regions, in which TAL effectors harbor their T3 and nuclear localization signals, and activation domain. We characterized a Btl protein, Btl19-13, and found that, despite the structural differences, it can be T3-secreted and can nuclear-localize. A btl19-13 gene knockout did not prevent the bacterium from infecting the fungus, but the fungus became less tolerant to cell membrane stress. Btl19-13 did not alter transcription in a plant-based reporter assay, but 15 R. microsporus genes were differentially expressed in comparisons both of the fungus infected with the wild-type bacterium vs. the mutant and with the mutant vs. a complemented strain. Southern blotting revealed btl genes in 14 diverse Mycetohabitans isolates. However, banding patterns and available sequences suggest variation, and the btl19-13 phenotype could not be rescued by a btl gene from a different strain. Our findings support the conclusion that Btl proteins are effectors that act on host DNA and play important but varied or possibly host genotype-specific roles in the M. rhizoxinica–R. microsporus symbiosis.
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Fungal Epigenetic Engineering. Fungal Biol 2020. [DOI: 10.1007/978-3-030-41870-0_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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