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Chávez-González JD, Flores-Núñez VM, Merino-Espinoza IU, Partida-Martínez LP. Desert plants, arbuscular mycorrhizal fungi and associated bacteria: Exploring the diversity and role of symbiosis under drought. ENVIRONMENTAL MICROBIOLOGY REPORTS 2024; 16:e13300. [PMID: 38979873 PMCID: PMC11231939 DOI: 10.1111/1758-2229.13300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Accepted: 05/08/2024] [Indexed: 07/10/2024]
Abstract
Desert plants, such as Agave tequilana, A. salmiana and Myrtillocactus geometrizans, can survive harsh environmental conditions partly due to their symbiotic relationships with microorganisms, including arbuscular mycorrhizal fungi (AMF). Interestingly, some of these fungi also harbour endosymbiotic bacteria. Our research focused on investigating the diversity of these AMFs and their associated bacteria in these plants growing in arid soil. We found that agaves have a threefold higher AMF colonization than M. geometrizans. Metabarcoding techniques revealed that the composition of AMF communities was primarily influenced by the plant host, while the bacterial communities were more affected by the specific plant compartment or niche they inhabited. We identified both known and novel endofungal bacterial taxa, including Burkholderiales, and confirmed their presence within AMF spores using multiphoton microscopy. Our study also explored the effects of drought on the symbiosis between A. tequilana and AMF. We discovered that the severity of drought conditions could modulate the strength of this symbiosis and its outcomes for the plant holobiont. Severe drought conditions prevented the formation of this symbiosis, while moderate drought conditions promoted it, thereby conferring drought tolerance in A. tequilana. This research sheds light on the diversity of AMF and associated bacteria in Crassulacean Acid Metabolism (CAM) plants and underscores the crucial role of drought as a factor modulating the symbiosis between A. tequilana and AMF. Further research is needed to understand the role of endofungal bacteria in this response.
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Affiliation(s)
- Jose Daniel Chávez-González
- Departamento de Ingeniería Genética, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (Cinvestav), Irapuato, Mexico
| | - Víctor M Flores-Núñez
- Departamento de Ingeniería Genética, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (Cinvestav), Irapuato, Mexico
| | - Irving U Merino-Espinoza
- Departamento de Ingeniería Genética, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (Cinvestav), Irapuato, Mexico
| | - Laila Pamela Partida-Martínez
- Departamento de Ingeniería Genética, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (Cinvestav), Irapuato, Mexico
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2
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Pawlowska TE. Symbioses between fungi and bacteria: from mechanisms to impacts on biodiversity. Curr Opin Microbiol 2024; 80:102496. [PMID: 38875733 PMCID: PMC11323152 DOI: 10.1016/j.mib.2024.102496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 05/20/2024] [Accepted: 05/31/2024] [Indexed: 06/16/2024]
Abstract
Symbiotic interactions between fungi and bacteria range from positive to negative. They are ubiquitous in free-living as well as host-associated microbial communities worldwide. Yet, the impact of fungal-bacterial symbioses on the organization and dynamics of microbial communities is uncertain. There are two reasons for this uncertainty: (1) knowledge gaps in the understanding of the genetic mechanisms underpinning fungal-bacterial symbioses and (2) prevailing interpretations of ecological theory that favor antagonistic interactions as drivers stabilizing biological communities despite the existence of models emphasizing contributions of positive interactions. This review synthesizes information on fungal-bacterial symbioses common in the free-living microbial communities of the soil as well as in host-associated polymicrobial biofilms. The interdomain partnerships are considered in the context of the relevant community ecology models, which are discussed critically.
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Affiliation(s)
- Teresa E Pawlowska
- School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, USA.
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3
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Baltrus DA, Carter M, Clark M, Smith C, Spraker J, Inderbitzin P, Arnold AE. Luteibacter mycovicinus sp. nov., a yellow-pigmented gammaproteobacterium found as an endohyphal symbiont of endophytic Ascomycota. Int J Syst Evol Microbiol 2024; 74:006240. [PMID: 38695275 PMCID: PMC11165876 DOI: 10.1099/ijsem.0.006240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 01/08/2024] [Indexed: 06/13/2024] Open
Abstract
We isolated and described a yellow-pigmented strain of bacteria (strain 9143T), originally characterized as an endohyphal inhabitant of an endophytic fungus in the Ascomycota. Although the full-length sequence of its 16S rRNA gene displays 99 % similarity to Luteibacter pinisoli, genomic hybridization demonstrated <30 % genomic similarity between 9143T and its closest named relatives, further supported by average nucleotide identity results. This and related endohyphal strains form a well-supported clade separate from L. pinisoli and other validly named species including the most closely related Luteibacter rhizovicinus. The name Luteibacter mycovicinus sp. nov. is proposed, with type strain 9143T (isolate DBL433), for which a genome has been sequenced and is publicly available from the American Type Culture Collection (ATCC TSD-257T) and from the Leibniz Institute DSMZ (DSM 112764T). The type strain reliably forms yellow colonies across diverse media and growth conditions (lysogeny broth agar, King's Medium B, potato dextrose agar, trypticase soy agar and Reasoner's 2A (R2A) agar). It forms colonies readily at 27 °C on agar with a pH of 6-8, and on salt (NaCl) concentrations up to 2 %. It lacks the ability to utilize sulphate as a sulphur source and thus only forms colonies on minimal media if supplemented with alternative sulphur sources. It is catalase-positive and oxidase-negative. Although it exhibits a single polar flagellum, motility was only clearly visible on R2A agar. Its host range and close relatives, which share the endohyphal lifestyle, are discussed.
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Affiliation(s)
- David A. Baltrus
- School of Plant Sciences, The University of Arizona, Tucson, AZ 85721, USA
- School of Animal and Comparative Biomedical Sciences, The University of Arizona, Tucson, AZ 85721, USA
| | - Morgan Carter
- School of Plant Sciences, The University of Arizona, Tucson, AZ 85721, USA
| | - Meara Clark
- School of Plant Sciences, The University of Arizona, Tucson, AZ 85721, USA
| | - Caitlin Smith
- School of Plant Sciences, The University of Arizona, Tucson, AZ 85721, USA
| | - Joseph Spraker
- School of Plant Sciences, The University of Arizona, Tucson, AZ 85721, USA
| | | | - A. Elizabeth Arnold
- School of Plant Sciences, The University of Arizona, Tucson, AZ 85721, USA
- Department of Ecology and Evolutionary Biology, The University of Arizona, Tucson, AZ 85721, USA
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4
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Zhang P, Huguet-Tapia J, Peng Z, Liu S, Obasa K, Block AK, White FF. Genome analysis and hyphal movement characterization of the hitchhiker endohyphal Enterobacter sp. from Rhizoctonia solani. Appl Environ Microbiol 2024; 90:e0224523. [PMID: 38319098 PMCID: PMC10952491 DOI: 10.1128/aem.02245-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 01/05/2024] [Indexed: 02/07/2024] Open
Abstract
Bacterial-fungal interactions are pervasive in the rhizosphere. While an increasing number of endohyphal bacteria have been identified, little is known about their ecology and impact on the associated fungal hosts and the surrounding environment. In this study, we characterized the genome of an Enterobacter sp. Crenshaw (En-Cren), which was isolated from the generalist fungal pathogen Rhizoctonia solani, and examined the genetic potential of the bacterium with regard to the phenotypic traits associated with the fungus. Overall, the En-Cren genome size was typical for members of the genus and was capable of free-living growth. The genome was 4.6 MB in size, and no plasmids were detected. Several prophage regions and genomic islands were identified that harbor unique genes in comparison with phylogenetically closely related Enterobacter spp. Type VI secretion system and cyanate assimilation genes were identified from the bacterium, while some common heavy metal resistance genes were absent. En-Cren contains the key genes for indole-3-acetic acid (IAA) and phenylacetic acid (PAA) biosynthesis, and produces IAA and PAA in vitro, which may impact the ecology or pathogenicity of the fungal pathogen in vivo. En-Cren was observed to move along hyphae of R. solani and on other basidiomycetes and ascomycetes in culture. The bacterial flagellum is essential for hyphal movement, while other pathways and genes may also be involved.IMPORTANCEThe genome characterization and comparative genomics analysis of Enterobacter sp. Crenshaw provided the foundation and resources for a better understanding of the ecology and evolution of this endohyphal bacteria in the rhizosphere. The ability to produce indole-3-acetic acid and phenylacetic acid may provide new angles to study the impact of phytohormones during the plant-pathogen interactions. The hitchhiking behavior of the bacterium on a diverse group of fungi, while inhibiting the growth of some others, revealed new areas of bacterial-fungal signaling and interaction, which have yet to be explored.
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Affiliation(s)
- Peiqi Zhang
- Department of Plant Pathology, University of Florida, Gainesville, Florida, USA
| | - Jose Huguet-Tapia
- Department of Plant Pathology, University of Florida, Gainesville, Florida, USA
| | - Zhao Peng
- Department of Plant Pathology, University of Florida, Gainesville, Florida, USA
- College of Plant Protection, Jilin Agricultural University, Changchun, Jilin, China
| | - Sanzhen Liu
- Department of Plant Pathology, Kansas State University, Manhattan, Kansas, USA
| | - Ken Obasa
- Department of Plant Pathology, University of Florida, Gainesville, Florida, USA
- High Plains Plant Disease Diagnostic Lab, Texas A&M AgriLife Extension Service, Amarillo, Texas, USA
| | - Anna K. Block
- Chemistry Research Unit, US Department of Agriculture-Agricultural Research Service, Gainesville, Florida, USA
| | - Frank F. White
- Department of Plant Pathology, University of Florida, Gainesville, Florida, USA
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Liang P, Jiang J, Sun Z, Li Y, Yang C, Zhou Y. Klebsiella michiganensis: a nitrogen-fixing endohyphal bacterium from Ustilago maydis. AMB Express 2023; 13:146. [PMID: 38112810 PMCID: PMC10730499 DOI: 10.1186/s13568-023-01618-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 10/03/2023] [Indexed: 12/21/2023] Open
Abstract
Ustilago maydis is a pathogenic fungus in Basidiomycota causing corn smut disease. A strain of U. maydis YZZF202006 was isolated from the tumor of corn smut collected from Jingzhou city in China. The intracellular bacteria were confirmed inner hyphal of the strain YZZF202006 by PCR amplification and fluorescence in situ hybridization (FISH) and SYTO-9. An endohyphal bacterium YZUMF202001 was isolated from the protoplasts of the strain YZZF202006. It was gram-negative, short rod-shaped with smooth light yellow colony. The endohyphal bacterium was genomic evidenced as Klebsiella michiganensis on the basis of average nucleotide identity (ANI) analysis and the phylogram. Then K. michiganensis was GFP-Labeled and reintroduced into U. maydis, which confirmed the bacterium can live in hyphae of U.maydis. The bacterium can grow on N-free culture media. Its nitrogenase activity was reached av. 646.25 ± 38.61 nmol·mL- 1·h- 1 C2H4 by acetylene reduction assay. A cluster of nitrogen fixation genes (nifJHDKTXENXUSVWZMFLABQ) was found from its genome. The endohyphal K. michiganensis may play an important role to help nitrogen fixation for fungi in the future.
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Affiliation(s)
- Pengyu Liang
- Department of Plant Protection, College of Agriculture, Yangtze University, Jingzhou, 434025, China
| | - Jianwei Jiang
- Department of Plant Protection, College of Agriculture, Yangtze University, Jingzhou, 434025, China
| | - Zhengxiang Sun
- Department of Plant Protection, College of Agriculture, Yangtze University, Jingzhou, 434025, China
| | - Yanyan Li
- Tobacco Research Institute of Hubei Province, Wuhan, 430000, China
| | - Chunlei Yang
- Tobacco Research Institute of Hubei Province, Wuhan, 430000, China.
| | - Yi Zhou
- Department of Plant Protection, College of Agriculture, Yangtze University, Jingzhou, 434025, China.
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6
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Njovu IK, Nalumaga PP, Ampaire L, Nuwagira E, Mwesigye J, Musinguzi B, Kassaza K, Taseera K, Kiguli Mukasa J, Bazira J, Iramiot JS, Baguma A, Bongomin F, Kwizera R, Achan B, Cox MJ, King JS, May R, Ballou ER, Itabangi H. Investigating Metabolic and Molecular Ecological Evolution of Opportunistic Pulmonary Fungal Coinfections: Protocol for a Laboratory-Based Cross-Sectional Study. JMIR Res Protoc 2023; 12:e48014. [PMID: 37581914 PMCID: PMC10466149 DOI: 10.2196/48014] [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: 04/09/2023] [Revised: 05/25/2023] [Accepted: 05/26/2023] [Indexed: 08/16/2023] Open
Abstract
BACKGROUND Fungal-bacterial cocolonization and coinfections pose an emerging challenge among patients suspected of having pulmonary tuberculosis (PTB); however, the underlying pathogenic mechanisms and microbiome interactions are poorly understood. Understanding how environmental microbes, such as fungi and bacteria, coevolve and develop traits to evade host immune responses and resist treatment is critical to controlling opportunistic pulmonary fungal coinfections. In this project, we propose to study the coexistence of fungal and bacterial microbial communities during chronic pulmonary diseases, with a keen interest in underpinning fungal etiological evolution and the predominating interactions that may exist between fungi and bacteria. OBJECTIVE This is a protocol for a study aimed at investigating the metabolic and molecular ecological evolution of opportunistic pulmonary fungal coinfections through determining and characterizing the burden, etiological profiles, microbial communities, and interactions established between fungi and bacteria as implicated among patients with presumptive PTB. METHODS This will be a laboratory-based cross-sectional study, with a sample size of 406 participants. From each participant, 2 sputa samples (one on-spot and one early morning) will be collected. These samples will then be analyzed for both fungal and bacterial etiology using conventional metabolic and molecular (intergenic transcribed spacer and 16S ribosomal DNA-based polymerase chain reaction) approaches. We will also attempt to design a genome-scale metabolic model for pulmonary microbial communities to analyze the composition of the entire microbiome (ie, fungi and bacteria) and investigate host-microbial interactions under different patient conditions. This analysis will be based on the interplays of genes (identified by metagenomics) and inferred from amplicon data and metabolites (identified by metabolomics) by analyzing the full data set and using specific computational tools. We will also collect baseline data, including demographic and clinical history, using a patient-reported questionnaire. Altogether, this approach will contribute to a diagnostic-based observational study. The primary outcome will be the overall fungal and bacterial diagnostic profile of the study participants. Other diagnostic factors associated with the etiological profile, such as incidence and prevalence, will also be analyzed using univariate and multivariate schemes. Odds ratios with 95% CIs will be presented with a statistical significance set at P<.05. RESULTS The study has been approved by the Mbarara University Research Ethic Committee (MUREC1/7-07/09/20) and the Uganda National Council of Science and Technology (HS1233ES). Following careful scrutiny, the protocol was designed to enable patient enrollment, which began in March 2022 at Mbarara University Teaching Hospital. Data collection is ongoing and is expected to be completed by August 2023, and manuscripts will be submitted for publication thereafter. CONCLUSIONS Through this protocol, we will explore the metabolic and molecular ecological evolution of opportunistic pulmonary fungal coinfections among patients with presumptive PTB. Establishing key fungal-bacterial cross-kingdom synergistic relationships is crucial for instituting fungal bacterial coinfecting etiology. TRIAL REGISTRATION ISRCTN Registry ISRCTN33572982; https://tinyurl.com/caa2nw69. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID) DERR1-10.2196/48014.
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Affiliation(s)
- Israel Kiiza Njovu
- Medical Mycology Unit, Department of Microbiology, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Pauline Petra Nalumaga
- Medical Mycology Unit, Department of Microbiology, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Lucas Ampaire
- Department of Medical Laboratory Sciences, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Edwin Nuwagira
- Department of Internal Medicine, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - James Mwesigye
- Medical Mycology Unit, Department of Microbiology, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Benson Musinguzi
- Department of Medical Laboratory Science, Faculty of Health Sciences, Muni University, Arua, Uganda
| | - Kennedy Kassaza
- Medical Mycology Unit, Department of Microbiology, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Kabanda Taseera
- Medical Mycology Unit, Department of Microbiology, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - James Kiguli Mukasa
- Department of Microbiology and Immunology, School of Health Sciences, Soroti University, Soroti, Uganda
| | - Joel Bazira
- Medical Mycology Unit, Department of Microbiology, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Jacob Stanley Iramiot
- Mycology Unit, Department of Microbiology and Immunology, Busitema University, Mbale, Uganda
| | - Andrew Baguma
- Department of Microbiology, School of Medicine, Kabale University, Kabale, Uganda
| | - Felix Bongomin
- Department of Microbiology and Immunology, Faculty of Medicine, Gulu University, Gulu, Uganda
| | - Richard Kwizera
- Infectious Diseases Institute, College of Health Sciences, Makerere University, Kampala, Uganda
| | - Beatrice Achan
- Department of Microbiology, School of Biomedical Sciences, College of Health Sciences, Makerere University, Kampala, Uganda
| | - Michael J Cox
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Jason S King
- School of Biosciences, Sheffield University, Sheffield, United Kingdom
| | - Robin May
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Elizabeth R Ballou
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Herbert Itabangi
- Medical Mycology Unit, Department of Microbiology, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
- Mycology Unit, Department of Microbiology and Immunology, Busitema University, Mbale, Uganda
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7
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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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Arnold AE. Bacterial-fungal interactions: Bacteria take up residence in the house that Fungi built. Curr Biol 2022; 32:R327-R328. [PMID: 35413262 DOI: 10.1016/j.cub.2022.02.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Interactions between bacteria and fungi are widespread in nature. New work shows that bacteria not known to have an endofungal lifestyle can take advantage of environmentally resistant fungal structures that are induced by lipopeptides from other bacteria. Diverse bacterial communities can flourish in these refugia to survive stressful conditions.
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Affiliation(s)
- A Elizabeth Arnold
- School of Plant Sciences and Department of Ecology and Evolutionary Biology, The University of Arizona, Tucson, AZ 85721, USA.
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9
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Transcriptional Profiles of a Foliar Fungal Endophyte ( Pestalotiopsis, Ascomycota) and Its Bacterial Symbiont ( Luteibacter, Gammaproteobacteria) Reveal Sulfur Exchange and Growth Regulation during Early Phases of Symbiotic Interaction. mSystems 2022; 7:e0009122. [PMID: 35293790 PMCID: PMC9040847 DOI: 10.1128/msystems.00091-22] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Symbiosis with bacteria is widespread among eukaryotes, including fungi. Bacteria that live within fungal mycelia (endohyphal bacteria) occur in many plant-associated fungi, including diverse Mucoromycota and Dikarya. Pestalotiopsis sp. strain 9143 is a filamentous ascomycete isolated originally as a foliar endophyte of Platycladus orientalis (Cupressaceae). It is infected naturally with the endohyphal bacterium Luteibacter sp. strain 9143, which influences auxin and enzyme production by its fungal host. Previous studies have used transcriptomics to examine similar symbioses between endohyphal bacteria and root-associated fungi such as arbuscular mycorrhizal fungi and plant pathogens. However, currently there are no gene expression studies of endohyphal bacteria of Ascomycota, the most species-rich fungal phylum. To begin to understand such symbioses, we developed methods for assessing gene expression by Pestalotiopsis sp. and Luteibacter sp. when grown in coculture and when each was grown axenically. Our assays showed that the density of Luteibacter sp. in coculture was greater than in axenic culture, but the opposite was true for Pestalotiopsis sp. Dual-transcriptome sequencing (RNA-seq) data demonstrate that growing in coculture modulates developmental and metabolic processes in both the fungus and bacterium, potentially through changes in the balance of organic sulfur via methionine acquisition. Our analyses also suggest an unexpected, potential role of the bacterial type VI secretion system in symbiosis establishment, expanding current understanding of the scope and dynamics of fungal-bacterial symbioses. IMPORTANCE Interactions between microbes and their hosts have important outcomes for host and environmental health. Foliar fungal endophytes that infect healthy plants can harbor facultative endosymbionts called endohyphal bacteria, which can influence the outcome of plant-fungus interactions. These bacterial-fungal interactions can be influential but are poorly understood, particularly from a transcriptome perspective. Here, we report on a comparative, dual-RNA-seq study examining the gene expression patterns of a foliar fungal endophyte and a facultative endohyphal bacterium when cultured together versus separately. Our findings support a role for the fungus in providing organic sulfur to the bacterium, potentially through methionine acquisition, and the potential involvement of a bacterial type VI secretion system in symbiosis establishment. This work adds to the growing body of literature characterizing endohyphal bacterial-fungal interactions, with a focus on a model facultative bacterial-fungal symbiosis in two species-rich lineages, the Ascomycota and Proteobacteria.
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10
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Itabangi H, Sephton-Clark PCS, Tamayo DP, Zhou X, Starling GP, Mahamoud Z, Insua I, Probert M, Correia J, Moynihan PJ, Gebremariam T, Gu Y, Ibrahim AS, Brown GD, King JS, Ballou ER, Voelz K. A bacterial endosymbiont of the fungus Rhizopus microsporus drives phagocyte evasion and opportunistic virulence. Curr Biol 2022; 32:1115-1130.e6. [PMID: 35134329 PMCID: PMC8926845 DOI: 10.1016/j.cub.2022.01.028] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 11/04/2021] [Accepted: 01/11/2022] [Indexed: 02/07/2023]
Abstract
Opportunistic infections by environmental fungi are a growing clinical problem, driven by an increasing population of people with immunocompromising conditions. Spores of the Mucorales order are ubiquitous in the environment but can also cause acute invasive infections in humans through germination and evasion of the mammalian host immune system. How they achieve this and the evolutionary drivers underlying the acquisition of virulence mechanisms are poorly understood. Here, we show that a clinical isolate of Rhizopus microsporus contains a Ralstonia pickettii bacterial endosymbiont required for virulence in both zebrafish and mice and that this endosymbiosis enables the secretion of factors that potently suppress growth of the soil amoeba Dictyostelium discoideum, as well as their ability to engulf and kill other microbes. As amoebas are natural environmental predators of both bacteria and fungi, we propose that this tri-kingdom interaction contributes to establishing endosymbiosis and the acquisition of anti-phagocyte activity. Importantly, we show that this activity also protects fungal spores from phagocytosis and clearance by human macrophages, and endosymbiont removal renders the fungal spores avirulent in vivo. Together, these findings describe a new role for a bacterial endosymbiont in Rhizopus microsporus pathogenesis in animals and suggest a mechanism of virulence acquisition through environmental interactions with amoebas.
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Affiliation(s)
- Herbert Itabangi
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Poppy C S Sephton-Clark
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Diana P Tamayo
- MRC Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK
| | - Xin Zhou
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Georgina P Starling
- School of Biosciences, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK
| | - Zamzam Mahamoud
- School of Biosciences, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK
| | - Ignacio Insua
- School of Chemistry, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Mark Probert
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Joao Correia
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Patrick J Moynihan
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Teclegiorgis Gebremariam
- The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, CA, USA
| | - Yiyou Gu
- The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, CA, USA
| | - Ashraf S Ibrahim
- The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, CA, USA; David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
| | - Gordon D Brown
- MRC Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK
| | - Jason S King
- School of Biosciences, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK.
| | - Elizabeth R Ballou
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK; MRC Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK.
| | - Kerstin Voelz
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
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11
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Friends or Foes-Microbial Interactions in Nature. BIOLOGY 2021; 10:biology10060496. [PMID: 34199553 PMCID: PMC8229319 DOI: 10.3390/biology10060496] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 05/27/2021] [Accepted: 05/31/2021] [Indexed: 12/16/2022]
Abstract
Simple Summary Microorganisms like bacteria, archaea, fungi, microalgae, and viruses mostly form complex interactive networks within the ecosystem rather than existing as single planktonic cells. Interactions among microorganisms occur between the same species, with different species, or even among entirely different genera, families, or even domains. These interactions occur after environmental sensing, followed by converting those signals to molecular and genetic information, including many mechanisms and classes of molecules. Comprehensive studies on microbial interactions disclose key strategies of microbes to colonize and establish in a variety of different environments. Knowledge of the mechanisms involved in the microbial interactions is essential to understand the ecological impact of microbes and the development of dysbioses. It might be the key to exploit strategies and specific agents against different facing challenges, such as chronic and infectious diseases, hunger crisis, pollution, and sustainability. Abstract Microorganisms are present in nearly every niche on Earth and mainly do not exist solely but form communities of single or mixed species. Within such microbial populations and between the microbes and a eukaryotic host, various microbial interactions take place in an ever-changing environment. Those microbial interactions are crucial for a successful establishment and maintenance of a microbial population. The basic unit of interaction is the gene expression of each organism in this community in response to biotic or abiotic stimuli. Differential gene expression is responsible for producing exchangeable molecules involved in the interactions, ultimately leading to community behavior. Cooperative and competitive interactions within bacterial communities and between the associated bacteria and the host are the focus of this review, emphasizing microbial cell–cell communication (quorum sensing). Further, metagenomics is discussed as a helpful tool to analyze the complex genomic information of microbial communities and the functional role of different microbes within a community and to identify novel biomolecules for biotechnological applications.
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12
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Muller LAH, Ballhausen MB, Andrade-Linares DR, Pinek L, Golubeva P, Rillig MC. Fungus-bacterium associations are widespread in fungal cultures isolated from a semi-arid natural grassland in Germany. FEMS Microbiol Ecol 2021; 97:6228834. [PMID: 33861336 DOI: 10.1093/femsec/fiab059] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 04/14/2021] [Indexed: 01/18/2023] Open
Abstract
We report on a study that aimed at establishing a large soil-fungal culture collection spanning a wide taxonomic diversity and systematically screening the collection for bacterial associations. Fungal cultures were isolated from soil samples obtained from a natural grassland in eastern Germany and bacterial associations were assessed by PCR-amplification and sequencing of bacterial 16S rRNA. In addition, intraspecies genetic diversities of a subset of the isolated species were estimated by double-digest restriction associated DNA sequencing. A total of 688 fungal cultures, representing at least 106 fungal species from 36 different families, were obtained and even though clonal isolates were identified in almost all fungal species subjected to ddRAD-seq, relatively high genetic diversities could be observed in some of the isolated species. A total of 69% of the fungal isolates in our collection were found to be associated with bacteria and the most commonly identified bacterial genera were Pelomonas, Enterobacter and Burkholderia. Our results indicate that bacterial associations commonly occur in soil fungi, even if antibiotics are being applied during the isolation process, and provide a basis for the use of our culture collection in ecological experiments that want to acknowledge the importance of intraspecies genetic diversity.
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Affiliation(s)
- L A H Muller
- Institut für Biologie - Ökologie der Pflanzen, Freie Universität Berlin, Altensteinstr. 6, 14195 Berlin, Germany.,Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 6, 14195 Berlin, Germany
| | - M-B Ballhausen
- Institut für Biologie - Ökologie der Pflanzen, Freie Universität Berlin, Altensteinstr. 6, 14195 Berlin, Germany.,Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 6, 14195 Berlin, Germany
| | - D R Andrade-Linares
- Research Unit Comparative Microbiome Analysis, Helmholtz Zentrum München, Ingolstaedter Landstraße 1, 85764 Neuherberg, Germany
| | - L Pinek
- Institut für Biologie - Ökologie der Pflanzen, Freie Universität Berlin, Altensteinstr. 6, 14195 Berlin, Germany.,Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 6, 14195 Berlin, Germany
| | - P Golubeva
- Institut für Biologie - Ökologie der Pflanzen, Freie Universität Berlin, Altensteinstr. 6, 14195 Berlin, Germany.,Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 6, 14195 Berlin, Germany
| | - M C Rillig
- Institut für Biologie - Ökologie der Pflanzen, Freie Universität Berlin, Altensteinstr. 6, 14195 Berlin, Germany.,Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 6, 14195 Berlin, Germany
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13
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Alibrandi P, Schnell S, Perotto S, Cardinale M. Diversity and Structure of the Endophytic Bacterial Communities Associated With Three Terrestrial Orchid Species as Revealed by 16S rRNA Gene Metabarcoding. Front Microbiol 2020; 11:604964. [PMID: 33519751 PMCID: PMC7839077 DOI: 10.3389/fmicb.2020.604964] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 11/23/2020] [Indexed: 01/13/2023] Open
Abstract
The endophytic microbiota can establish mutualistic or commensalistic interactions within the host plant tissues. We investigated the bacterial endophytic microbiota in three species of Mediterranean orchids (Neottia ovata, Serapias vomeracea, and Spiranthes spiralis) by metabarcoding of the 16S rRNA gene. We examined whether the different orchid species and organs, both underground and aboveground, influenced the endophytic bacterial communities. A total of 1,930 operational taxonomic units (OTUs) were obtained, mainly Proteobacteria and Actinobacteria, whose distribution model indicated that the plant organ was the main determinant of the bacterial community structure. The co-occurrence network was not modular, suggesting a relative homogeneity of the microbiota between both plant species and organs. Moreover, the decrease in species richness and diversity in the aerial vegetative organs may indicate a filtering effect by the host plant. We identified four hub OTUs, three of them already reported as plant-associated taxa (Pseudoxanthomonas, Rhizobium, and Mitsuaria), whereas Thermus was an unusual member of the plant microbiota. Core microbiota analysis revealed a selective and systemic ascent of bacterial communities from the vegetative to the reproductive organs. The core microbiota was also maintained in the S. spiralis seeds, suggesting a potential vertical transfer of the microbiota. Surprisingly, some S. spiralis seed samples displayed a very rich endophytic microbiota, with a large number of OTUs shared with the roots, a situation that may lead to a putative restoring process of the root-associated microbiota in the progeny. Our results indicate that the bacterial community has adapted to colonize the orchid organs selectively and systemically, suggesting an active involvement in the orchid holobiont.
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Affiliation(s)
- Pasquale Alibrandi
- Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy
- Institute of Applied Microbiology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Sylvia Schnell
- Institute of Applied Microbiology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Silvia Perotto
- Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy
| | - Massimiliano Cardinale
- Institute of Applied Microbiology, Justus-Liebig-University Giessen, Giessen, Germany
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Lecce, Italy
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14
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Abstract
All multicellular organisms are associated with a diverse and specific community of microorganisms; consequently, the microbiome is of fundamental importance for health and fitness of the multicellular host. However, studies on microbiome contribution to host fitness are in their infancy, in particular, for less well-established hosts such as the moon jellyfish Aurelia aurita. Here, we studied the impact of the native microbiome on the asexual reproduction and on further fitness traits (health, growth, and feeding) of the basal metazoan due to induced changes in its microbiome. We observed significant impact on all fitness traits analyzed, in particular, in the absence of the protective microbial shield and when challenged with marine potentially pathogenic bacterial isolates. Notable is the identified crucial importance of the native microbiome for the generation of offspring, consequently affecting life cycle decisions. Thus, we conclude that the microbiome is essential for the maintenance of a healthy metaorganism. All multicellular organisms are associated with microbial communities, ultimately forming a metaorganism. Several studies conducted on well-established model organisms point to immunological, metabolic, and behavioral benefits of the associated microbiota for the host. Consequently, a microbiome can influence the physiology of a host; moreover, microbial community shifts can affect host health and fitness. The present study aimed to evaluate the significance and functional role of the native microbiota for life cycle transitions and fitness of the cnidarian moon jellyfish Aurelia aurita. A comprehensive host fitness experiment was conducted studying the polyp life stage and integrating 12 combinations of treatments with microbiota modification (sterile conditions, foreign food bacteria, and potential pathogens). Asexual reproduction, e.g., generation of daughter polyps, and the formation and release of ephyrae were highly affected in the absence of the native microbiota, ultimately resulting in a halt of strobilation and ephyra release. Assessment of further fitness traits showed that health, growth, and feeding rate were decreased in the absence and upon community changes of the native microbiota, e.g., when challenged with selected bacteria. Moreover, changes in microbial community patterns were detected by 16S rRNA amplicon sequencing during the course of the experiment. This demonstrated that six operational taxonomic units (OTUs) significantly correlated and explained up to 97% of fitness data variability, strongly supporting the association of impaired fitness with the absence/presence of specific bacteria. Conclusively, our study provides new insights into the importance and function of the microbiome for asexual reproduction, health, and fitness of the basal metazoan A. aurita.
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15
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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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16
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Abstract
Diverse strains of Luteibacter (Gammaproteobacteria) have been isolated from a variety of environments, most frequently in association with both plants and fungi. Motivated by the lack of genomic information for strains throughout the genus Luteibacter, we report here a complete genome sequence for Luteibacter pinisoli strain MAH-14. Diverse strains of Luteibacter (Gammaproteobacteria) have been isolated from a variety of environments, most frequently in association with both plants and fungi. Motivated by the lack of genomic information for strains throughout the genus Luteibacter, we report here a complete genome sequence for Luteibacter pinisoli strain MAH-14.
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17
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Chang Y, Desirò A, Na H, Sandor L, Lipzen A, Clum A, Barry K, Grigoriev IV, Martin FM, Stajich JE, Smith ME, Bonito G, Spatafora JW. Phylogenomics of Endogonaceae and evolution of mycorrhizas within Mucoromycota. THE NEW PHYTOLOGIST 2019; 222:511-525. [PMID: 30485448 DOI: 10.1111/nph.15613] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Accepted: 10/29/2018] [Indexed: 06/09/2023]
Abstract
Endogonales (Mucoromycotina), composed of Endogonaceae and Densosporaceae, is the only known non-Dikarya order with ectomycorrhizal members. They also form mycorrhizal-like association with some nonspermatophyte plants. It has been recently proposed that Endogonales were among the earliest mycorrhizal partners with land plants. It remains unknown whether Endogonales possess genomes with mycorrhizal-lifestyle signatures and whether Endogonales originated around the same time as land plants did. We sampled sporocarp tissue from four Endogonaceae collections and performed shotgun genome sequencing. After binning the metagenome data, we assembled and annotated the Endogonaceae genomes. We performed comparative analysis on plant-cell-wall-degrading enzymes (PCWDEs) and small secreted proteins (SSPs). We inferred phylogenetic placement of Endogonaceae and estimated the ages of Endogonaceae and Endogonales with expanded taxon sampling. Endogonaceae have large genomes with high repeat content, low diversity of PCWDEs, but without elevated SSP/secretome ratios. Dating analysis estimated that Endogonaceae originated in the Permian-Triassic boundary and Endogonales originated in the mid-late Silurian. Mycoplasma-related endobacterium sequences were identified in three Endogonaceae genomes. Endogonaceae genomes possess typical signatures of mycorrhizal lifestyle. The early origin of Endogonales suggests that the mycorrhizal association between Endogonales and plants might have played an important role during the colonization of land by plants.
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Affiliation(s)
- Ying Chang
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, 97331, USA
| | - Alessandro Desirò
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, 48824, USA
| | - Hyunsoo Na
- US Department of Energy Joint Genome Institute, Walnut Creek, CA, 94598, USA
| | - Laura Sandor
- US Department of Energy Joint Genome Institute, Walnut Creek, CA, 94598, USA
| | - Anna Lipzen
- US Department of Energy Joint Genome Institute, Walnut Creek, CA, 94598, USA
| | - Alicia Clum
- US Department of Energy Joint Genome Institute, Walnut Creek, CA, 94598, USA
| | - Kerrie Barry
- US Department of Energy Joint Genome Institute, Walnut Creek, CA, 94598, USA
| | - Igor V Grigoriev
- US Department of Energy Joint Genome Institute, Walnut Creek, CA, 94598, USA
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, CA, 94720, USA
| | - Francis M Martin
- Institut national de la recherche agronomique, Laboratoire d'excellence ARBRE, Centre INRA-Grand Est, Unité mixte de recherche Inra-Université de Lorraine "Interactions Arbres/Microorganismes", 54280, Champenoux, France
| | - Jason E Stajich
- Department of Microbiology and Plant Pathology, University of California, Riverside, CA, 92521, USA
| | - Matthew E Smith
- Department of Plant Pathology, University of Florida, Gainesville, FL, 32611, USA
| | - Gregory Bonito
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, 48824, USA
| | - Joseph W Spatafora
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, 97331, USA
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18
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Jaspers C, Fraune S, Arnold AE, Miller DJ, Bosch TCG, Voolstra CR. Resolving structure and function of metaorganisms through a holistic framework combining reductionist and integrative approaches. ZOOLOGY 2019; 133:81-87. [PMID: 30979392 DOI: 10.1016/j.zool.2019.02.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 02/20/2019] [Accepted: 02/27/2019] [Indexed: 02/07/2023]
Abstract
Current research highlights the importance of associated microbes in contributing to the functioning, health, and even adaptation of their animal, plant, and fungal hosts. As such, we are witnessing a shift in research that moves away from focusing on the eukaryotic host sensu stricto to research into the complex conglomerate of the host and its associated microorganisms (i.e., microbial eukaryotes, archaea, bacteria, and viruses), the so-called metaorganism, as the biological entity. While recent research supports and encourages the adoption of such an integrative view, it must be understood that microorganisms are not involved in all host processes and not all associated microorganisms are functionally important. As such, our intention here is to provide a critical review and evaluation of perspectives and limitations relevant to studying organisms in a metaorganism framework and the functional toolbox available to do so. We note that marker gene-guided approaches that primarily characterize microbial diversity are a first step in delineating associated microbes but are not sufficient to establish proof of their functional relevance. More sophisticated tools and experiments are necessary to reveal the specific functions of associated microbes. This can be accomplished through the study of metaorganisms in less complex environments, the targeted manipulation of microbial associates, or work at the mechanistic level with the toolbox available in model systems. We conclude that the metaorganism framework is a powerful new concept to help provide answers to longstanding biological questions such as the evolution and ecology of organismal complexity and the importance of organismal symbioses to ecosystem functioning. The intricacy of the metaorganism requires a holistic framework combining reductionist and integrative approaches to resolve the structure and function of its member species and to disclose the various roles that microorganisms play in the biology of their hosts.
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Affiliation(s)
- Cornelia Jaspers
- GEOMAR - Helmholtz Centre for Ocean Research Kiel, Evolutionary Ecology of Marine Fishes, Düsternbrooker Weg 20, 24105 Kiel, Germany; National Institute of Aquatic Resources, Technical University of Denmark, DTU Aqua, Kemitorvet, Building 202, 2800 Kgs. Lyngby, Denmark
| | - Sebastian Fraune
- Zoological Institute, Kiel University, Am Botanischen Garten 9, 24118 Kiel, Germany
| | - A Elizabeth Arnold
- School of Plant Sciences and the Department of Ecology and Evolutionary Biology, The University of Arizona, Tucson, AZ 85719, USA
| | - David J Miller
- ARC Centre of Excellence for Coral Reef Studies and Department of Molecular and Cell Biology, James Cook University, Townsville, Queensland 4811, Australia
| | - Thomas C G Bosch
- Zoological Institute, Kiel University, Am Botanischen Garten 9, 24118 Kiel, Germany
| | - Christian R Voolstra
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia.
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19
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Davis WJ, Amses KR, Benny GL, Carter-House D, Chang Y, Grigoriev I, Smith ME, Spatafora JW, Stajich JE, James TY. Genome-scale phylogenetics reveals a monophyletic Zoopagales (Zoopagomycota, Fungi). Mol Phylogenet Evol 2019; 133:152-163. [PMID: 30639767 DOI: 10.1016/j.ympev.2019.01.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 12/25/2018] [Accepted: 01/04/2019] [Indexed: 11/26/2022]
Abstract
Previous genome-scale phylogenetic analyses of Fungi have under sampled taxa from Zoopagales; this order contains many predacious or parasitic genera, and most have never been grown in pure culture. We sequenced the genomes of 4 zoopagalean taxa that are predators of amoebae, nematodes, or rotifers and the genome of one taxon that is a parasite of amoebae using single cell sequencing methods with whole genome amplification. Each genome was a metagenome, which was assembled and binned using multiple techniques to identify the target genomes. We inferred phylogenies with both super matrix and coalescent approaches using 192 conserved proteins mined from the target genomes and performed ancestral state reconstructions to determine the ancestral trophic lifestyle of the clade. Our results indicate that Zoopagales is monophyletic. Ancestral state reconstructions provide moderate support for mycoparasitism being the ancestral state of the clade.
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Affiliation(s)
- William J Davis
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, United States
| | - Kevin R Amses
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, United States
| | - Gerald L Benny
- Department of Plant Pathology, University of Florida, Gainesville, FL, United States
| | - Derreck Carter-House
- Department of Microbiology and Plant Pathology, University of California-Riverside, United States
| | - Ying Chang
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, United States
| | - Igor Grigoriev
- United States of America Department of Energy Joint Genome Institute, Walnut Creek, CA, United States
| | - Matthew E Smith
- Department of Plant Pathology, University of Florida, Gainesville, FL, United States
| | - Joseph W Spatafora
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, United States
| | - Jason E Stajich
- Department of Microbiology and Plant Pathology, University of California-Riverside, United States
| | - Timothy Y James
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, United States.
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Shaffer JP, Zalamea PC, Sarmiento C, Gallery RE, Dalling JW, Davis AS, Baltrus DA, Arnold AE. Context-dependent and variable effects of endohyphal bacteria on interactions between fungi and seeds. FUNGAL ECOL 2018. [DOI: 10.1016/j.funeco.2018.08.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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21
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Baltrus DA, Spraker J, Arnold AE. Quantifying Re-association of a Facultative Endohyphal Bacterium with a Filamentous Fungus. Methods Mol Biol 2018; 1848:1-11. [PMID: 30182224 DOI: 10.1007/978-1-4939-8724-5_1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We present here a method to quantify reassociation between facultative endohyphal bacteria and filamentous fungal hosts. Our method takes advantage of the capabilities of fungal cell walls to selectively protect internal bacteria from gentamicin treatment, an assay adapted from studies of internalized bacterial pathogens in cell culture. We report the efficacy of gentamicin to kill planktonic bacteria treated during fungal coculture, and also describe and characterize a sampling scheme to recover and quantify culturable bacteria from the growing edge of fungal mycelium in vitro. This assay enables qualitative and quantitative tests of reassociation capabilities for facultative endohyphal bacteria with host fungi and provides a means to investigate the genetic basis for these associations in a repeatable way.
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Affiliation(s)
- David A Baltrus
- School of Plant Sciences, University of Arizona, Tucson, AZ, USA.
- School of Animal and Comparative Biomedical Sciences, University of Arizona, Tucson, AZ, USA.
| | - Joseph Spraker
- School of Plant Sciences, University of Arizona, Tucson, AZ, USA
| | - A Elizabeth Arnold
- School of Plant Sciences, University of Arizona, Tucson, AZ, USA
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, USA
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22
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James TY, Seifert KA. Description of Bifiguratus adelaidae: The hunt ends for one of the "Top 50 Most Wanted Fungi". Mycologia 2017; 109:361-362. [PMID: 28876180 DOI: 10.1080/00275514.2017.1372667] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Timothy Y James
- a Department of Ecology and Evolutionary Biology , University of Michigan , Ann Arbor , Michigan 48109
| | - Keith A Seifert
- b Ottawa Research and Development Centre , Agriculture and Agri-Food Canada , Ottawa , Ontario K1A 0C6 , Canada
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