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Marine Fungi Select and Transport Aerobic and Anaerobic Bacterial Populations from Polycyclic Aromatic Hydrocarbon-Contaminated Sediments. mBio 2023; 14:e0276122. [PMID: 36786561 PMCID: PMC10127579 DOI: 10.1128/mbio.02761-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
The organization of microbial communities in marine sediment relies on complex biotic and abiotic interactions. Among them, the interaction between fungi and bacteria plays a crucial role building specific microbial assemblages, resulting in metabolic networks adapted to environmental conditions. The fungal-bacterial interaction (FBI) includes bacterial translocation via fungal mycelia, allowing bacterial dispersion, and ecological niche colonization. In order to demonstrate that the translocation of bacteria through fungal mycelia involves bacterial selection, the mycelia of two fungi isolated from marine coastal sediment, Alternaria destruens F10.81 and Fusarium pseudonygamai F5.76, showing different strategies for uptake of polycyclic aromatic hydrocarbon (PAH), homogenous internalization and vacuole forming respectively, were used to translocate bacteria through hydrophobic hydrocarbon contaminated sediments. A. destruens F10.81 selected four specific bacteria, while bacterial selection by F. pseudonygamai F5.76 was not evident. Among the bacteria selected by A. destruens F10.81, Spirochaeta litoralis, known as strictly anaerobic bacterium, was identified, indicating that A. destruens F10.81 selects and transports both aerobic and anaerobic bacteria. Such a result is consistent with the observed formation of anoxic micro-niches in areas surrounding and affected by fungal hyphae. Our findings provide new insights on the selection and dispersion of bacterial communities by fungi, which are crucial for the organization of microbial communities and their functioning in coastal PAH-contaminated sediments. IMPORTANCE The study provides advances for understanding fungal-bacterial relationships, particularly on the selection and dispersion of bacterial communities by fungi, which are crucial for the organization of microbial communities and their functioning in coastal PAH-contaminated sediments. The transportation of bacteria via fungal hyphae (fungal highway) results in bacterial selection; in particular, fungal hyphae offer adequate conditions for the transport of both aerobic and anaerobic bacteria through hydrophobic patches for the colonization of novel niches.
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The Wheat Head Blight Pathogen Fusarium graminearum Can Recruit Collaborating Bacteria from Soil. Cells 2022; 11:cells11193004. [PMID: 36230966 PMCID: PMC9563980 DOI: 10.3390/cells11193004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 09/15/2022] [Accepted: 09/21/2022] [Indexed: 11/17/2022] Open
Abstract
In nature, fungal endophytes often have facultative endohyphal bacteria (FEB). Can a model plant pathogenic fungus have them, and does it affect their phenotype? We constructed a growth system/microcosm to allow an F. graminearum isolate to grow through natural soil and then re-isolated it on a gentamicin-containing medium, allowing endohyphal growth of bacteria while killing other bacteria. F. graminearum PH-1 labelled with a His1mCherry gene staining the fungal nuclei fluorescent red was used to confirm the re-isolation of the fungus. Most new re-isolates contained about 10 16SrRNA genes per fungal mCherry gene determined by qPCR. The F. graminearum + FEB holobiont isolates containing the bacteria were sub-cultured several times, and their bacterial contents were stable. Sequencing the bacterial 16SrRNA gene from several Fg-FEB holobiont isolates revealed endophytic bacteria known to be capable of nitrogen fixation. We tested the pathogenicity of one common Fg-FEB holobiont association, F. graminearum + Stenatrophomonas maltophilia, and found increased pathogenicity. The 16SrRNA gene load per fungal His1mCherry gene inside the wheat stayed the same as previously found in vitro. Finally, strong evidence was found for Fg-S. maltophilia symbiotic nitrogen fixation benefitting the fungus.
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3
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Yang T, Tang G, Li L, Ma L, Zhao Y, Guo Z. Interactions between bacteria and eukaryotic microorganisms and their response to soil properties and heavy metal exchangeability nearby a coal-fired power plant. CHEMOSPHERE 2022; 302:134829. [PMID: 35523290 DOI: 10.1016/j.chemosphere.2022.134829] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 04/27/2022] [Accepted: 04/29/2022] [Indexed: 06/14/2023]
Abstract
Persistent heavy metal (HM) contaminated soil provides special habitat for microorganisms, HM stress and complex abiotic factors bring great uncertainty for the development of bacteria and eukaryotic microbes. Despite numerous studies about HMs' effect on soil microorganisms, the key factors affecting microbial communities in severe HM contaminated soil and their interactions are still not definite. In this study, the effect of HM fractions and soil properties on the interaction between bacterial communities and eukaryotic microorganisms was studied by high-throughput Illumina sequencing and simplified continuous extraction of HM in severe HM contaminated soil. Based on amplification and sequencing of the 18S rRNA gene, this study revealed that protists and algae were the most predominant eukaryotic microorganisms, and the dominant phyla were SAR, Opisthokonta and Archaeplastida in HM seriously polluted soil. These results also showed that exchangeable As was negatively correlated with bacterial Shannon and Simpson indexes, while exchangeable Zn was positively correlated with Shannon and Simpson indexes of eukaryotic microbes. Moreover, the structural equation model illustrated that pH, moisture content, available potassium and phosphorus, and exchangeable Cd, As and Zn were the dominant factors shaping bacterial communities, while total organic carbon and exchangeable Zn made the predominant contributions to variations in eukaryotic microbes. In addition, eukaryotic microbes were intensely affected by the bacterial communities, with a standardized regression weight of 0.53, which exceeded the influence of other abiotic factors. It was suggested that community-level adaptions through cooperative interactions under serious HM stress in soil.
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Affiliation(s)
- Tongyi Yang
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, PR China.
| | - Guoteng Tang
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, PR China
| | - Ling Li
- Zhenjiang Customs District, Integrated Technology Center, Zhenjiang 212000, PR China
| | - Liuchang Ma
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, PR China
| | - Yuyuan Zhao
- Zhenjiang Key Laboratory of Functional Chemistry, Institute of Medicine & Chemical Engineering, Zhenjiang College, Zhenjiang 212000, China
| | - Zechong Guo
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, PR China
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4
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Snelders NC, Rovenich H, Thomma BPHJ. Microbiota manipulation through the secretion of effector proteins is fundamental to the wealth of lifestyles in the fungal kingdom. FEMS Microbiol Rev 2022; 46:6590816. [PMID: 35604874 PMCID: PMC9438471 DOI: 10.1093/femsre/fuac022] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 05/19/2022] [Indexed: 11/13/2022] Open
Abstract
Fungi are well-known decomposers of organic matter that thrive in virtually any environment on earth where they encounter wealths of other microbes. Some fungi evolved symbiotic lifestyles, including pathogens and mutualists, that have mostly been studied in binary interactions with their hosts. However, we now appreciate that such interactions are greatly influenced by the ecological context in which they take place. While establishing their symbioses, fungi not only interact with their hosts, but also with the host-associated microbiota. Thus, they target the host and its associated microbiota as a single holobiont. Recent studies have shown that fungal pathogens manipulate the host microbiota by means of secreted effector proteins with selective antimicrobial activity to stimulate disease development. In this review we discuss the ecological contexts in which such effector-mediated microbiota manipulation is relevant for the fungal lifestyle and argue that this is not only relevant for pathogens of plants and animals, but beneficial in virtually any niche where fungi occur. Moreover, we reason that effector-mediated microbiota manipulation likely evolved already in fungal ancestors that encountered microbial competition long before symbiosis with land plants and mammalian animals evolved. Thus, we claim that effector-mediated microbiota manipulation is fundamental to fungal biology.
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Affiliation(s)
- Nick C Snelders
- Institute for Plant Sciences, University of Cologne, Cologne, Germany.,Theoretical Biology & Bioinformatics Group, Department of Biology, Utrecht University, Utrecht, The Netherlands
| | - Hanna Rovenich
- Institute for Plant Sciences, University of Cologne, Cologne, Germany
| | - Bart P H J Thomma
- Institute for Plant Sciences, University of Cologne, Cologne, Germany.,Cluster of Excellence on Plant Sciences, Institute for Plant Sciences, University of Cologne, CologneGermany
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5
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You X, Kallies R, Kühn I, Schmidt M, Harms H, Chatzinotas A, Wick LY. Phage co-transport with hyphal-riding bacteria fuels bacterial invasion in a water-unsaturated microbial model system. THE ISME JOURNAL 2022; 16:1275-1283. [PMID: 34903848 PMCID: PMC9039081 DOI: 10.1038/s41396-021-01155-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 11/09/2021] [Accepted: 11/11/2021] [Indexed: 11/09/2022]
Abstract
Nonmotile microorganisms often enter new habitats by co-transport with motile microorganisms. Here, we report that also lytic phages can co-transport with hyphal-riding bacteria and facilitate bacterial colonization of a new habitat. This is comparable to the concept of biological invasions in macroecology. In analogy to invasion frameworks in plant and animal ecology, we tailored spatially organized, water-unsaturated model microcosms using hyphae of Pythium ultimum as invasion paths and flagellated soil-bacterium Pseudomonas putida KT2440 as carrier for co-transport of Escherichia virus T4. P. putida KT2440 efficiently dispersed along P. ultimum to new habitats and dispatched T4 phages across air gaps transporting ≈0.6 phages bacteria−1. No T4 displacement along hyphae was observed in the absence of carrier bacteria. If E. coli occupied the new habitat, T4 co-transport fueled the fitness of invading P. putida KT2440, while the absence of phage co-transport led to poor colonization followed by extinction. Our data emphasize the importance of hyphal transport of bacteria and associated phages in regulating fitness and composition of microbial populations in water-unsaturated systems. As such co-transport seems analogous to macroecological invasion processes, hyphosphere systems with motile bacteria and co-transported phages could be useful models for testing hypotheses in invasion ecology.
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Affiliation(s)
- Xin You
- Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Microbiology, Permoserstr. 15, 04318, Leipzig, Germany
| | - René Kallies
- Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Microbiology, Permoserstr. 15, 04318, Leipzig, Germany
| | - Ingolf Kühn
- Helmholtz Centre for Environmental Research - UFZ, Department of Community Ecology, Theodor-Lieser-Str. 4, 06120, Halle, Germany.,Institute of Biology/Geobotany and Botanical Garden, Martin Luther University Halle-Wittenberg, Halle, Germany.,German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, 04103, Leipzig, Germany
| | - Matthias Schmidt
- Helmholtz Centre for Environmental Research - UFZ, Department of Isotope Biogeochemistry, Permoserstr. 15, 04318, Leipzig, Germany
| | - Hauke Harms
- Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Microbiology, Permoserstr. 15, 04318, Leipzig, Germany.,German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, 04103, Leipzig, Germany
| | - Antonis Chatzinotas
- Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Microbiology, Permoserstr. 15, 04318, Leipzig, Germany.,German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, 04103, Leipzig, Germany.,Institute of Biology, Leipzig University, Talstr. 33, Leipzig, 04103, Germany
| | - Lukas Y Wick
- Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Microbiology, Permoserstr. 15, 04318, Leipzig, Germany.
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6
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Mycelia-Assisted Isolation of Non-Host Bacteria Able to Co-Transport Phages. Viruses 2022; 14:v14020195. [PMID: 35215789 PMCID: PMC8877629 DOI: 10.3390/v14020195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 01/14/2022] [Accepted: 01/17/2022] [Indexed: 11/27/2022] Open
Abstract
Recent studies have demonstrated that phages can be co-transported with motile non-host bacteria, thereby enabling their invasion of biofilms and control of biofilm composition. Here, we developed a novel approach to isolate non-host bacteria able to co-transport phages from soil. It is based on the capability of phage-carrying non-host bacteria to move along mycelia out of soil and form colonies in plaques of their co-transported phages. The approach was tested using two model phages of differing surface hydrophobicity, i.e., hydrophobic Escherichia virus T4 (T4) and hydrophilic Pseudoalteromonas phage HS2 (HS2). The phages were mixed into soil and allowed to be transported by soil bacteria along the mycelia of Pythium ultimum. Five phage-carrying bacterial species were isolated (Viridibacillus sp., Enterobacter sp., Serratia sp., Bacillus sp., Janthinobacterium sp.). These bacteria exhibited phage adsorption efficiencies of ≈90–95% for hydrophobic T4 and 30–95% for hydrophilic HS2. The phage adsorption efficiency of Viridibacillus sp. was ≈95% for both phages and twofold higher than T4-or HS2-adsorption to their respective hosts, qualifying Viridibacillus sp. as a potential super carrier for phages. Our approach offers an effective and target-specific way to identify and isolate phage-carrying bacteria in natural and man-made environments.
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Shapiro T, Chekanov K, Alexandrova A, Dolnikova G, Ivanova E, Lobakova E. Revealing of Non-Cultivable Bacteria Associated with the Mycelium of Fungi in the Kerosene-Degrading Community Isolated from the Contaminated Jet Fuel. J Fungi (Basel) 2021; 7:jof7010043. [PMID: 33440907 PMCID: PMC7826599 DOI: 10.3390/jof7010043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 12/31/2020] [Accepted: 01/08/2021] [Indexed: 11/25/2022] Open
Abstract
Fuel (especially kerosene) biodamage is a challenge for global industry. In aviation, where kerosene is a widely used type of fuel, its biodeterioration leads to significant damage. Six isolates of micromycetes from the TS-1 aviation kerosene samples were obtained. Their ability to grow on the fuel was studied, and the difference between biodegradation ability was shown. Micromycetes belonged to the Talaromyces, Penicillium, and Aspergillus genera. It was impossible to obtain bacterial isolates associated with their mycelium. However, 16S rRNA metabarcoding and microscopic observations revealed the presence of bacteria in the micromycete isolates. It seems to be that kerosene-degrading fungi were associated with uncultured bacteria. Proteobacteria, Actinobacteria, Bacteroidetes, and Firmicutes were abundant in the fungal cultures isolated from the TS-1 jet fuel samples. Most genera among these phyla are known as hydrocarbon degraders. Only bacteria-containing micromycete isolates were able to grow on the kerosene. Most likely, kerosene degradation mechanisms are based on synergism of bacteria and fungi.
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Affiliation(s)
- Tatiana Shapiro
- Faculty of Biology, Lomonosov Moscow State University, 1-12 Leninskie Gory, 119192 Moscow, Russia; (T.S.); (A.A.); (G.D.); (E.L.)
| | - Konstantin Chekanov
- Faculty of Biology, Lomonosov Moscow State University, 1-12 Leninskie Gory, 119192 Moscow, Russia; (T.S.); (A.A.); (G.D.); (E.L.)
- Centre for Humanities Research and Technology, National Research Nuclear University MEPhI, 31 Kashirskoye highway, 115522 Moscow, Russia
- Correspondence:
| | - Alina Alexandrova
- Faculty of Biology, Lomonosov Moscow State University, 1-12 Leninskie Gory, 119192 Moscow, Russia; (T.S.); (A.A.); (G.D.); (E.L.)
| | - Galina Dolnikova
- Faculty of Biology, Lomonosov Moscow State University, 1-12 Leninskie Gory, 119192 Moscow, Russia; (T.S.); (A.A.); (G.D.); (E.L.)
| | - Ekaterina Ivanova
- Department of General and Inorganic Chemistry, National University of Oil and Gas “Gubkin University”, 65 Leninsky Prospekt, 119991 Moscow, Russia;
| | - Elena Lobakova
- Faculty of Biology, Lomonosov Moscow State University, 1-12 Leninskie Gory, 119192 Moscow, Russia; (T.S.); (A.A.); (G.D.); (E.L.)
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8
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de Novais CB, Sbrana C, da Conceição Jesus E, Rouws LFM, Giovannetti M, Avio L, Siqueira JO, Saggin Júnior OJ, da Silva EMR, de Faria SM. Mycorrhizal networks facilitate the colonization of legume roots by a symbiotic nitrogen-fixing bacterium. MYCORRHIZA 2020; 30:389-396. [PMID: 32215759 DOI: 10.1007/s00572-020-00948-w] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 03/16/2020] [Indexed: 05/22/2023]
Abstract
Arbuscular mycorrhizal fungi (AMF) absorb and translocate nutrients from soil to their host plants by means of a wide network of extraradical mycelium (ERM). Here, we assessed whether nitrogen-fixing rhizobia can be transferred to the host legume Glycine max by ERM produced by Glomus formosanum isolate CNPAB020 colonizing the grass Urochloa decumbens. An H-bridge experimental system was developed to evaluate the migration of ERM and of the GFP-tagged Bradyrhizobium diazoefficiens USDA 110 strain across an air gap compartment. Mycorrhizal colonization, nodule formation in legumes, and occurrence of the GFP-tagged strain in root nodules were assessed by optical and confocal laser scanning microscopy. In the presence of non-mycorrhizal U. decumbens, legume roots were neither AMF-colonized nor nodulated. In contrast, G. formosanum ERM crossing the discontinuous compartment connected mycorrhizal U. decumbens and G. max roots, which showed 30-42% mycorrhizal colonization and 7-11 nodules per plant. Fluorescent B. diazoefficiens cells were detected in 94% of G. max root nodules. Our findings reveal that, besides its main activity in nutrient transfer, ERM produced by AMF may facilitate bacterial translocation and the simultaneous associations of plants with beneficial fungi and bacteria, representing an important structure, functional to the establishment of symbiotic relationships.
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Affiliation(s)
- Candido Barreto de Novais
- Instituto de Floresta, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ, 23890-000, Brazil
| | - Cristiana Sbrana
- CNR-Institute of Agricultural Biology and Biotechnology UOS Pisa, Pisa, Italy.
| | | | | | - Manuela Giovannetti
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
| | - Luciano Avio
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
| | - José Oswaldo Siqueira
- DCS-Laboratório de Microbiologia do Solo, Universidade Federal de Lavras, Caixa Postal 3037, Lavras, MG, 37200-000, Brazil
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9
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Yu Z, Han H, Feng P, Zhao S, Zhou T, Kakade A, Kulshrestha S, Majeed S, Li X. Recent advances in the recovery of metals from waste through biological processes. BIORESOURCE TECHNOLOGY 2020; 297:122416. [PMID: 31786035 DOI: 10.1016/j.biortech.2019.122416] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 11/08/2019] [Accepted: 11/10/2019] [Indexed: 06/10/2023]
Abstract
Wastes containing critical metals are generated in various fields, such as energy and computer manufacturing. Metal-bearing wastes are considered as secondary sources of critical metals. The conventional physicochemical methods of metals recovery are energy-intensive and cause further pollution. Low-cost and eco-friendly technologies including biosorbents, bioelectrochemical systems (BESs), bioleaching, and biomineralization, have become alternatives in the recovery of critical metals. However, a relatively low recovery rate and selectivity severely hinder their large-scale applications. Researchers have expanded their focus to exploit novel strain resources and strategies to improve the biorecovery efficiency. The mechanisms and potential applicability of modified biological techniques for improving the recovery of critical metals need more attention. Hence, this review summarize and compare the strategies that have been developed for critical metals recovery, and provides useful insights for energy-efficient recovery of critical metals in future industrial applications.
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Affiliation(s)
- Zhengsheng Yu
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Science, Lanzhou University, No. 222 Tianshuinan Road, Lanzhou, Gansu 730000, People's Republic of China
| | - Huawen Han
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Science, Lanzhou University, No. 222 Tianshuinan Road, Lanzhou, Gansu 730000, People's Republic of China
| | - Pengya Feng
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Science, Lanzhou University, No. 222 Tianshuinan Road, Lanzhou, Gansu 730000, People's Republic of China
| | - Shuai Zhao
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Science, Lanzhou University, No. 222 Tianshuinan Road, Lanzhou, Gansu 730000, People's Republic of China
| | - Tuoyu Zhou
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Science, Lanzhou University, No. 222 Tianshuinan Road, Lanzhou, Gansu 730000, People's Republic of China
| | - Apurva Kakade
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Science, Lanzhou University, No. 222 Tianshuinan Road, Lanzhou, Gansu 730000, People's Republic of China
| | - Saurabh Kulshrestha
- Faculty of Applied Sciences and Biotechnology, Shoolini University of Biotechnology and Management Sciences, Bajhol, Solan, Himachal Pradesh 173229, India
| | - Sabahat Majeed
- Department of Biosciences, COMSATS University, Park Road, Tarlai Kalan Islamabad, Islamabad 44000, Pakistan
| | - Xiangkai Li
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Science, Lanzhou University, No. 222 Tianshuinan Road, Lanzhou, Gansu 730000, People's Republic of China.
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10
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Hao X, Zhu YG, Nybroe O, Nicolaisen MH. The Composition and Phosphorus Cycling Potential of Bacterial Communities Associated With Hyphae of Penicillium in Soil Are Strongly Affected by Soil Origin. Front Microbiol 2020; 10:2951. [PMID: 31969866 PMCID: PMC6960115 DOI: 10.3389/fmicb.2019.02951] [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: 08/04/2019] [Accepted: 12/09/2019] [Indexed: 02/05/2023] Open
Abstract
Intimate fungal-bacterial interactions are widespread in nature. However the main drivers for the selection of hyphae-associated bacterial communities and their functional traits in soil systems remain elusive. In the present study, baiting microcosms were used to recover hyphae-associated bacteria from two Penicillium species with different phosphorus-solubilizing capacities in five types of soils. Based on amplicon sequencing of 16S rRNA genes, the composition of bacterial communities associated with Penicillium hyphae differed significantly from the soil communities, showing a lower diversity and less variation in taxonomic structure. Furthermore, soil origin had a significant effect on hyphae-associated community composition, whereas the two fungal species used in this study had no significant overall impact on bacterial community structure, despite their different capacities to solubilize phosphorus. However, discriminative taxa and specific OTUs were enriched in hyphae-associated communities of individual Penicillium species indicating that each hyphosphere represented a unique niche for bacterial colonization. Additionally, an increased potential of phosphorus cycling was found in hyphae-associated communities, especially for the gene phnK involved in phosphonate degradation. Altogether, it was established that the two Penicillium hyphae represent unique niches in which microbiome assemblage and phosphorus cycling potential are mainly driven by soil origin, with less impact made by fungal identity with a divergent capacity to utilize phosphorus.
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Affiliation(s)
- Xiuli Hao
- Section for Microbial Ecology and Biotechnology, Department of Plant and Environmental Sciences, University of Copenhagen, Copenhagen, Denmark
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, Wuhan, China
| | - Yong-Guan Zhu
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China
- State Key Lab of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
| | - Ole Nybroe
- Section for Microbial Ecology and Biotechnology, Department of Plant and Environmental Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Mette H. Nicolaisen
- Section for Microbial Ecology and Biotechnology, Department of Plant and Environmental Sciences, University of Copenhagen, Copenhagen, Denmark
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11
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Shan Y, Harms H, Wick LY. Electric Field Effects on Bacterial Deposition and Transport in Porous Media. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:14294-14301. [PMID: 30418019 DOI: 10.1021/acs.est.8b03648] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Bacterial deposition and transport are key to microbial ecology and biotechnological applications. We therefore tested whether electrokinetic forces (electroosmotic shear force ( FEOF), electrophoretic drag force ( FEP)) acting on bacteria may be used to control bacterial deposition during transport in laboratory percolation columns exposed to external direct current (DC) electric fields. For different bacteria, yet similar experimental conditions we observed that DC fields either enhanced or reduced bacterial deposition efficiencies (α) relative to DC-free controls. By calculating the DLVO force of colloidal interactions, FEOF, FEP, and the hydraulic shear forces acting on single cells at a collector surface we found that DC-induced changes of α correlated to | FEOF| to | FEP| ratios: If | FEOF| > | FEP|, α was clearly increased and if | FEOF| < | FEP| α was clearly decreased. Our findings allow for better prediction of the forces acting on a bacterium at collector surface and, hence, the electrokinetic control of microbial deposition in natural and manmade ecosystems.
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Affiliation(s)
- Yongping Shan
- UFZ - Helmholtz Centre for Environmental Research , Department of Environmental Microbiology , Permoserstrasse 15 , 04318 Leipzig , Germany
| | - Hauke Harms
- UFZ - Helmholtz Centre for Environmental Research , Department of Environmental Microbiology , Permoserstrasse 15 , 04318 Leipzig , Germany
| | - Lukas Y Wick
- UFZ - Helmholtz Centre for Environmental Research , Department of Environmental Microbiology , Permoserstrasse 15 , 04318 Leipzig , Germany
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12
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Worrich A, Wick LY, Banitz T. Ecology of Contaminant Biotransformation in the Mycosphere: Role of Transport Processes. ADVANCES IN APPLIED MICROBIOLOGY 2018; 104:93-133. [PMID: 30143253 DOI: 10.1016/bs.aambs.2018.05.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Fungi and bacteria often share common microhabitats. Their co-occurrence and coevolution give rise to manifold ecological interactions in the mycosphere, here defined as the microhabitats surrounding and affected by hyphae and mycelia. The extensive structure of mycelia provides ideal "logistic networks" for transport of bacteria and matter in structurally and chemically heterogeneous soil ecosystems. We describe the characteristics of the mycosphere as a unique and highly dynamic bacterial habitat and a hot spot for contaminant biotransformation. In particular, we emphasize the role of the mycosphere for (i) bacterial dispersal and colonization of subsurface interfaces and new habitats, (ii) matter transport processes and contaminant bioaccessibility, and (iii) the functional stability of microbial ecosystems when exposed to environmental fluctuations such as stress or disturbances. Adopting concepts from ecological theory, the chapter disentangles bacterial-fungal impacts on contaminant biotransformation in a systemic approach that interlinks empirical data from microbial ecosystems with simulation data from computational models. This approach provides generic information on key factors, processes, and ecological principles that drive microbial contaminant biotransformation in soil. We highlight that the transport processes create favorable habitat conditions for efficient bacterial contaminant degradation in the mycosphere. In-depth observation, understanding, and prediction of the role of mycosphere transport processes will support the use of bacterial-fungal interactions in nature-based solutions for contaminant biotransformation in natural and man-made ecosystems, respectively.
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Affiliation(s)
- Anja Worrich
- Department of Environmental Microbiology, UFZ-Helmholtz Centre for Environmental Research, Leipzig, Germany
| | - Lukas Y Wick
- Department of Environmental Microbiology, UFZ-Helmholtz Centre for Environmental Research, Leipzig, Germany.
| | - Thomas Banitz
- Department of Ecological Modelling, UFZ-Helmholtz Centre for Environmental Research, Leipzig, Germany
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13
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Ghodsalavi B, Svenningsen NB, Hao X, Olsson S, Nicolaisen MH, Al-Soud WA, Sørensen SJ, Nybroe O. A novel baiting microcosm approach used to identify the bacterial community associated with Penicillium bilaii hyphae in soil. PLoS One 2017; 12:e0187116. [PMID: 29077733 PMCID: PMC5659649 DOI: 10.1371/journal.pone.0187116] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 10/13/2017] [Indexed: 11/18/2022] Open
Abstract
It is important to identify and recover bacteria associating with fungi under natural soil conditions to enable eco-physiological studies, and to facilitate the use of bacterial-fungal consortia in environmental biotechnology. We have developed a novel type of baiting microcosm, where fungal hyphae interact with bacteria under close-to-natural soil conditions; an advantage compared to model systems that determine fungal influences on bacterial communities in laboratory media. In the current approach, the hyphae are placed on a solid support, which enables the recovery of hyphae with associated bacteria in contrast to model systems that compare bulk soil and mycosphere soil. We used the baiting microcosm approach to determine, for the first time, the composition of the bacterial community associating in the soil with hyphae of the phosphate-solubilizer, Penicillium bilaii. By applying a cultivation-independent 16S rRNA gene-targeted amplicon sequencing approach, we found a hypha-associated bacterial community with low diversity compared to the bulk soil community and exhibiting massive dominance of Burkholderia OTUs. Burkholderia is known be abundant in soil environments affected by fungi, but the discovery of this massive dominance among bacteria firmly associating with hyphae in soil is novel and made possible by the current bait approach.
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Affiliation(s)
- Behnoushsadat Ghodsalavi
- Section for Microbial Ecology and Biotechnology, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Nanna Bygvraa Svenningsen
- Section for Microbial Ecology and Biotechnology, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Xiuli Hao
- Section for Microbial Ecology and Biotechnology, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Stefan Olsson
- Section for Microbial Ecology and Biotechnology, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg C, Denmark
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Mette Haubjerg Nicolaisen
- Section for Microbial Ecology and Biotechnology, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Waleed Abu Al-Soud
- Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Søren J. Sørensen
- Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Ole Nybroe
- Section for Microbial Ecology and Biotechnology, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg C, Denmark
- * E-mail:
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14
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Nazir R, Mazurier S, Yang P, Lemanceau P, van Elsas JD. The Ecological Role of Type Three Secretion Systems in the Interaction of Bacteria with Fungi in Soil and Related Habitats Is Diverse and Context-Dependent. Front Microbiol 2017; 8:38. [PMID: 28197129 PMCID: PMC5282467 DOI: 10.3389/fmicb.2017.00038] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 01/06/2017] [Indexed: 12/14/2022] Open
Abstract
Bacteria and fungi constitute important organisms in many ecosystems, in particular terrestrial ones. Both organismal groups contribute significantly to biogeochemical cycling processes. Ecological theory postulates that bacteria capable of receiving benefits from host fungi are likely to evolve efficient association strategies. The purpose of this review is to examine the mechanisms that underpin the bacterial interactions with fungi in soil and other systems, with special focus on the type III secretion system (T3SS). Starting with a brief description of the versatility of the T3SS as an interaction system with diverse eukaryotic hosts, we subsequently examine the recent advances made in our understanding of its contribution to interactions with soil fungi. The analysis used data sets ranging from circumstantial evidence to gene-knockout-based experimental data. The initial finding that the abundance of T3SSs in microbiomes is often enhanced in fungal-affected habitats like the mycosphere and the mycorrhizosphere is now substantiated with in-depth knowledge of the specific systems involved. Different fungal–interactive bacteria, in positive or negative associations with partner fungi, harbor and express T3SSs, with different ecological outcomes. In some particular cases, bacterial T3SSs have been shown to modulate the physiology of its fungal partner, affecting its ecological characteristics and consequently shaping its own habitat. Overall, the analyses of the collective data set revealed that diverse T3SSs have assumed diverse roles in the interactions of bacteria with host fungi, as driven by ecological and evolutionary niche requirements.
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Affiliation(s)
- Rashid Nazir
- Department of Environmental Sciences, COMSATS Institute of Information TechnologyAbbottabad, Pakistan; Department of Soil Environmental Science, Research Centre for Eco-environmental Sciences - Chinese Academy of SciencesBeijing, China
| | - Sylvie Mazurier
- Agroécologie, AgroSup Dijon, Institut National de la Recherche Agronomique, Université Bourgogne Franche-Comté Dijon, France
| | - Pu Yang
- Department of Microbial Ecology, GELIFES, University of Groningen Groningen, Netherlands
| | - Philippe Lemanceau
- Agroécologie, AgroSup Dijon, Institut National de la Recherche Agronomique, Université Bourgogne Franche-Comté Dijon, France
| | - Jan Dirk van Elsas
- Department of Microbial Ecology, GELIFES, University of Groningen Groningen, Netherlands
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15
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Biodegradation of polycyclic aromatic hydrocarbons by an acidophilic Stenotrophomonas maltophilia strain AJH1 isolated from a mineral mining site in Saudi Arabia. Extremophiles 2016; 21:163-174. [DOI: 10.1007/s00792-016-0892-0] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 11/07/2016] [Indexed: 10/20/2022]
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16
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Berthold T, Centler F, Hübschmann T, Remer R, Thullner M, Harms H, Wick LY. Mycelia as a focal point for horizontal gene transfer among soil bacteria. Sci Rep 2016; 6:36390. [PMID: 27811990 PMCID: PMC5095653 DOI: 10.1038/srep36390] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 10/12/2016] [Indexed: 11/09/2022] Open
Abstract
Horizontal gene transfer (HGT) is a main mechanism of bacterial evolution endowing bacteria with new genetic traits. The transfer of mobile genetic elements such as plasmids (conjugation) requires the close proximity of cells. HGT between genetically distinct bacteria largely depends on cell movement in water films, which are typically discontinuous in natural systems like soil. Using laboratory microcosms, a bacterial reporter system and flow cytometry, we here investigated if and to which degree mycelial networks facilitate contact of and HGT between spatially separated bacteria. Our study shows that the network structures of mycelia promote bacterial HGT by providing continuous liquid films in which bacterial migration and contacts are favoured. This finding was confirmed by individual-based simulations, revealing that the tendency of migrating bacteria to concentrate in the liquid film around hyphae is a key factor for improved HGT along mycelial networks. Given their ubiquity, we propose that hyphae can act as focal point for HGT and genetic adaptation in soil.
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Affiliation(s)
- Tom Berthold
- Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Microbiology, Permoserstraße 15, 04318, Leipzig, Germany
| | - Florian Centler
- Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Microbiology, Permoserstraße 15, 04318, Leipzig, Germany
| | - Thomas Hübschmann
- Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Microbiology, Permoserstraße 15, 04318, Leipzig, Germany
| | - Rita Remer
- Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Microbiology, Permoserstraße 15, 04318, Leipzig, Germany
| | - Martin Thullner
- Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Microbiology, Permoserstraße 15, 04318, Leipzig, Germany
| | - Hauke Harms
- Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Microbiology, Permoserstraße 15, 04318, Leipzig, Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5E, 04103 Leipzig, Germany
| | - Lukas Y. Wick
- Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Microbiology, Permoserstraße 15, 04318, Leipzig, Germany
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17
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Simon A, Hervé V, Al-Dourobi A, Verrecchia E, Junier P. An in situ inventory of fungi and their associated migrating bacteria in forest soils using fungal highway columns. FEMS Microbiol Ecol 2016; 93:fiw217. [PMID: 27797964 DOI: 10.1093/femsec/fiw217] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 03/04/2016] [Accepted: 10/18/2016] [Indexed: 11/13/2022] Open
Abstract
Soils are complex ecosystems in which fungi and bacteria co-exist and interact. Fungal highways are a kind of interaction by which bacteria use fungal hyphae to disperse in soils. Despite the fact that fungal highways have been studied in laboratory models, the diversity of fungi and bacteria interacting in this way in soils is still unknown. Fungal highway columns containing two different culture media were used as a selective method to study the identity of fungi and bacteria able to migrate along the hyphae in three forest soils. Regardless of the soil type, fungi of the genus Mortierella (phylum Zygomycota) were selected inside the columns. In contrast, a diverse community of bacteria dominated by Firmicutes and Proteobacteria was observed. The results confirm the importance of bacteria affiliated to Burkholderia as potentially associated migrating bacteria in soils and indicate that other groups such as Bacillus and Clostridium are also highly enriched in the co-colonization of a new habitat (columns) associated to Mortierella. The diversity of potentially associated migrating bacteria brings a novel perspective on the indirect metabolic capabilities that could be favored by r-strategist fungi and supports the fact that these fungi should be considered as crucial actors in soil functioning.
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Affiliation(s)
- Anaele Simon
- Laboratory of Microbiology, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland
| | - Vincent Hervé
- Laboratory of Microbiology, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland.,Biogeosciences laboratory, Institute of Earth Surface Dynamics, University of Lausanne, 1015 Lausanne, Switzerland
| | - Andrej Al-Dourobi
- Laboratory of Microbiology, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland
| | - Eric Verrecchia
- Biogeosciences laboratory, Institute of Earth Surface Dynamics, University of Lausanne, 1015 Lausanne, Switzerland
| | - Pilar Junier
- Laboratory of Microbiology, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland
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Simon A, Bindschedler S, Job D, Wick LY, Filippidou S, Kooli WM, Verrecchia EP, Junier P. Exploiting the fungal highway: development of a novel tool for thein situisolation of bacteria migrating along fungal mycelium. FEMS Microbiol Ecol 2015; 91:fiv116. [DOI: 10.1093/femsec/fiv116] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/27/2015] [Indexed: 01/06/2023] Open
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19
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Nazir R, Tazetdinova DI, van Elsas JD. Burkholderia terrae BS001 migrates proficiently with diverse fungal hosts through soil and provides protection from antifungal agents. Front Microbiol 2014; 5:598. [PMID: 25426111 PMCID: PMC4227525 DOI: 10.3389/fmicb.2014.00598] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Accepted: 10/22/2014] [Indexed: 11/26/2022] Open
Abstract
Soil bacteria can benefit from co-occurring soil fungi in respect of the acquisition of carbonaceous nutrients released by fungal hyphae and the access to novel territories in soil. Here, we investigated the capacity of the mycosphere-isolated bacterium Burkholderia terrae BS001 to comigrate through soil along with hyphae of the soil fungi Trichoderma asperellum, Rhizoctonia solani, Fusarium oxysporum, F. oxysporum pv lini, Coniochaeta ligniaria, Phanerochaete velutina, and Phallus impudicus. We used Lyophyllum sp. strain Karsten as the reference migration-inciting fungus. Bacterial migration through presterilized soil on the extending fungal hyphae was detected with six of the seven test fungi, with only Phallus impudicus not showing any bacterial transport. Much like with Lyophyllum sp. strain Karsten, intermediate (106–108 CFU g-1 dry soil) to high (>108 CFU g-1 dry soil) strain BS001 cell population sizes were found at the hyphal migration fronts of four fungi, i.e., T. asperellum, Rhizoctonia solani, F. oxysporum and F. oxysporum pv lini, whereas for two fungi, Coniochaeta ligniaria and Phanerochaete velutina, the migration responses were retarded and population sizes were lower (103–106 CFU g-1 dry soil). Consistent with previous data obtained with the reference fungus, migration with the migration-inciting fungi occurred only in the direction of the hyphal growth front. Remarkably, Burkholderia terrae BS001 provided protection from several antifungal agents to the canonical host Lyophyllum sp. strain Karsten. Specifically, this host was protected from Pseudomonas fluorescens strain CHA0 metabolites, as well as from the anti-fungal agent cycloheximide. Similar protection by strain BS001was observed for T. asperellum, and, to a lower extent, F. oxysporum and Rhizoctonia solani. The protective effect may be related to the consistent occurrence of biofilm-like cell layers or agglomerates at the surfaces of the protected fungi. The current study represents the first report of protection of soil fungi against antagonistic agents present in the soil provided by fungal-associated Burkholderia terrae cells.
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Affiliation(s)
- Rashid Nazir
- Department of Microbial Ecology, Centre for Ecological and Evolutionary Studies, University of Groningen Groningen, The Netherlands
| | - Diana I Tazetdinova
- Department of Microbial Ecology, Centre for Ecological and Evolutionary Studies, University of Groningen Groningen, The Netherlands
| | - Jan Dirk van Elsas
- Department of Microbial Ecology, Centre for Ecological and Evolutionary Studies, University of Groningen Groningen, The Netherlands
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20
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Bravo D, Cailleau G, Bindschedler S, Simon A, Job D, Verrecchia E, Junier P. Isolation of oxalotrophic bacteria able to disperse on fungal mycelium. FEMS Microbiol Lett 2013; 348:157-66. [PMID: 24106816 DOI: 10.1111/1574-6968.12287] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 09/17/2013] [Accepted: 09/17/2013] [Indexed: 11/28/2022] Open
Abstract
A technique based on an inverted Petri dish system was developed for the growth and isolation of soil oxalotrophic bacteria able to disperse on fungal mycelia. The method is related to the 'fungal highways' dispersion theory in which mycelial fungal networks allow active movement of bacteria in soil. Quantification of this phenomenon showed that bacterial dispersal occurs preferentially in upper soil horizons. Eight bacteria and one fungal strain were isolated by this method. The oxalotrophic activity of the isolated bacteria was confirmed through calcium oxalate dissolution in solid selective medium. After separation of the bacteria-fungus couple, partial sequencing of the 16S and the ITS1 and ITS2 sequences of the ribosomal RNA genes were used for the identification of bacteria and the associated fungus. The isolated oxalotrophic bacteria included strains related to Stenotrophomonas, Achromobacter, Lysobacter, Pseudomonas, Agrobacterium, Cohnella, and Variovorax. The recovered fungus corresponded to Trichoderma sp. A test carried out to verify bacterial transport in an unsaturated medium showed that all the isolated bacteria were able to migrate on Trichoderma hyphae or glass fibers to re-colonize an oxalate-rich medium. The results highlight the importance of fungus-driven bacterial dispersal to understand the functional role of oxalotrophic bacteria and fungi in soils.
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Affiliation(s)
- Daniel Bravo
- Laboratory of Microbiology, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland
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