1
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Kuga Y, Wu TD, Sakamoto N, Katsuyama C, Yurimoto H. Allocation of Carbon from an Arbuscular Mycorrhizal Fungus, Gigaspora margarita, to Its Gram-Negative and Positive Endobacteria Revealed by High-Resolution Secondary Ion Mass Spectrometry. Microorganisms 2021; 9:microorganisms9122597. [PMID: 34946198 PMCID: PMC8705746 DOI: 10.3390/microorganisms9122597] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Revised: 12/12/2021] [Accepted: 12/13/2021] [Indexed: 11/23/2022] Open
Abstract
Arbuscular mycorrhizal fungi are obligate symbionts of land plants; furthermore, some of the species harbor endobacteria. Although the molecular approach increased our knowledge of the diversity and origin of the endosymbiosis and its metabolic possibilities, experiments to address the functions of the fungal host have been limited. In this study, a C flow of the fungus to the bacteria was investigated. Onion seedlings colonized with Gigaspora margarita, possessing Candidatus Glomeribacter gigasporarum (CaGg, Gram-negative, resides in vacuole) and Candidatus Moeniiplasma glomeromycotorum (CaMg, Gram-positive, resides in the cytoplasm,) were labelled with 13CO2. The 13C localization within the mycorrhiza was analyzed using high-resolution secondary ion mass spectrometry (SIMS). Correlative TEM-SIMS analysis of the fungal cells revealed that the 13C/12C ratio of CaGg was the lowest among CaMg and mitochondria and was the highest in the cytoplasm. By contrast, the plant cells, mitochondria, plastids, and fungal cytoplasm, which are contributors to the host, showed significantly higher 13C enrichment than the host cytoplasm. The C allocation patterns implied that CaMg has a greater impact than CaGg on G. margarita, but both seemed to be less burdensome to the host fungus in terms of C cost.
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Affiliation(s)
- Yukari Kuga
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima 739-8521, Hiroshima, Japan;
- Correspondence:
| | - Ting-Di Wu
- Institut Curie, Université PSL, CNRS UMS2016, Inserm US43, Université Paris-Saclay, Multimodal Imaging Center, 91400 Orsay, France;
| | - Naoya Sakamoto
- Isotope Imaging Laboratory, Creative Research Institution, Hokkaido University, Kita-21 Nishi-11, Kita-ku, Sapporo 001-0021, Hokkaido, Japan;
| | - Chie Katsuyama
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima 739-8521, Hiroshima, Japan;
| | - Hisayoshi Yurimoto
- Department of Natural History Sciences, Hokkaido University, Kita-21 Nishi-11, Kita-ku, Sapporo 001-0021, Hokkaido, Japan;
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2
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Sun Q, Fu Z, Finlay R, Lian B. Transcriptome Analysis Provides Novel Insights into the Capacity of the Ectomycorrhizal Fungus Amanita pantherina To Weather K-Containing Feldspar and Apatite. Appl Environ Microbiol 2019; 85:e00719-19. [PMID: 31126945 PMCID: PMC6643233 DOI: 10.1128/aem.00719-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 05/18/2019] [Indexed: 02/05/2023] Open
Abstract
Ectomycorrhizal (ECM) fungi, symbiotically associated with woody plants, markedly improve the uptake of mineral nutrients such as potassium (K) and phosphorus (P) by their host trees. Although it is well known that ECM fungi can obtain K and P from soil minerals through biological weathering, the mechanisms regulating this process are still poorly understood at the molecular level. Here, we investigated the transcriptional regulation of the ECM fungus Amanita pantherina in weathering K-containing feldspar and apatite using transcriptome sequencing (RNA-seq) and validated these results for differentially expressed genes using real-time quantitative PCR. The results showed that A. pantherina was able to improve relevant metabolic processes, such as promoting the biosynthesis of unsaturated fatty acids and steroids in the weathering of K-containing feldspar and apatite. The expression of genes encoding ion transporters was markedly enhanced during exposure to solid K-containing feldspar and apatite, and transcripts of the high-affinity K transporter ApHAK1, belonging to the HAK family, were significantly upregulated. The results also demonstrated that there was no upregulation of organic acid biosynthesis, reflecting the weak weathering capacity of the A. pantherina isolate used in this study, especially its inability to utilize P in apatite. Our findings suggest that under natural conditions in forests, some ECM fungi with low weathering potential of their own may instead enhance the uptake of mineral nutrients using their high-affinity ion transporter systems.IMPORTANCE In this study, we revealed the molecular mechanism and possible strategies of A. pantherina with weak weathering potential in the uptake of insoluble mineral nutrients by using transcriptome sequencing (RNA-seq) technology and found that ApHAK1, a K transporter gene of this fungus, plays a very important role in the acquisition of K and P. Ectomycorrhizal (ECM) fungi play critical roles in the uptake of woody plant nutrients in forests that are usually characterized by nutrient limitation and in maintaining the stability of forest ecosystems. However, the regulatory mechanisms of ECM fungi in acquiring nutrients from minerals/rocks are poorly understood. This study investigated the transcriptional regulation of A. pantherina weathering K-containing feldspar and apatite and improves the understanding of fungal-plant interactions in promoting plant nutrition enabling increased productivity in sustainable forestry.
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Affiliation(s)
- Qibiao Sun
- Jiangsu Key Laboratory for Microbes and Functional Genomics, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Ziyu Fu
- Jiangsu Key Laboratory for Microbes and Functional Genomics, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Roger Finlay
- Department of Forest Mycology and Plant Pathology, Uppsala BioCenter, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Bin Lian
- Jiangsu Key Laboratory for Microbes and Functional Genomics, College of Life Sciences, Nanjing Normal University, Nanjing, China
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3
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Nehls U, Plassard C. Nitrogen and phosphate metabolism in ectomycorrhizas. THE NEW PHYTOLOGIST 2018; 220:1047-1058. [PMID: 29888395 DOI: 10.1111/nph.15257] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 05/01/2018] [Indexed: 05/23/2023]
Abstract
1047 I. Introduction 1047 II. Mobilization of soil N/P by ECM fungi 1048 III. N/P uptake 1048 IV. N/P assimilation 1049 V. N/P storage and remobilization 1049 VI. Hyphal N/P efflux at the plant-fungus interface 1052 VII. Conclusion and research needs 1054 Acknowledgements 1055 References 1055 SUMMARY: Nutrient homeostasis is essential for fungal cells and thus tightly adapted to the local demand in a mycelium with hyphal specialization. Based on selected ectomycorrhizal (ECM) fungal models, we outlined current concepts of nitrogen and phosphate nutrition and their limitations, and included knowledge from Baker's yeast when major gaps had to be filled. We covered the entire pathway from nutrient mobilization, import and local storage, distribution within the mycelium and export at the plant-fungus interface. Even when nutrient import and assimilation were broad issues for ECM fungi, we focused mainly on nitrate and organic phosphorus uptake, as other nitrogen/phosphorus (N/P) sources have been covered by recent reviews. Vacuolar N/P storage and mobilization represented another focus point of this review. Vacuoles are integrated into cellular homeostasis and central for an ECM mycelium at two locations: soil-growing hyphae and hyphae of the plant-fungus interface. Vacuoles are also involved in long-distance transport. We further discussed potential mechanisms of bidirectional long-distance nutrient transport (distances from millimetres to metres). A final focus of the review was N/P export at the plant-fungus interface, where we compared potential efflux mechanisms and pathways, and discussed their prerequisites.
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Affiliation(s)
- Uwe Nehls
- Botany, University of Bremen, Bremen, 28359, Germany
| | - Claude Plassard
- Eco & Sols, Université de Montpellier, INRA, CIRAD, IRD, Montpellier SupAgro, Montpellier, 34060, France
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4
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Becquer A, Garcia K, Amenc L, Rivard C, Doré J, Trives-Segura C, Szponarski W, Russet S, Baeza Y, Lassalle-Kaiser B, Gay G, Zimmermann SD, Plassard C. The Hebeloma cylindrosporum HcPT2 Pi transporter plays a key role in ectomycorrhizal symbiosis. THE NEW PHYTOLOGIST 2018; 220:1185-1199. [PMID: 29944179 DOI: 10.1111/nph.15281] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 05/28/2018] [Indexed: 05/23/2023]
Abstract
Through a mutualistic relationship with woody plant roots, ectomycorrhizal fungi provide growth-limiting nutrients, including inorganic phosphate (Pi), to their host. Reciprocal trades occur at the Hartig net, which is the symbiotic interface of ectomycorrhizas where the two partners are symplasmically isolated. Fungal Pi must be exported to the symbiotic interface, but the proteins facilitating this transfer are unknown. In the present study, we combined transcriptomic, microscopy, whole plant physiology, X-ray fluorescence mapping, 32 P labeling and fungal genetic approaches to unravel the role of HcPT2, a fungal Pi transporter, during the Hebeloma cylindrosporum-Pinus pinaster ectomycorrhizal association. We localized HcPT2 in the extra-radical hyphae and the Hartig net and demonstrated its determinant role for both the establishment of ectomycorrhizas and Pi allocation towards P. pinaster. We showed that the host plant induces HcPT2 expression and that the artificial overexpression of HcPT2 is sufficient to significantly enhance Pi export towards the central cylinder. Together, our results reveal that HcPT2 plays an important role in ectomycorrhizal symbiosis, affecting both Pi influx in the mycelium and efflux towards roots under the control of P. pinaster.
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Affiliation(s)
- Adeline Becquer
- Eco & Sols, Université de Montpellier, CIRAD, INRA, IRD, Montpellier SupAgro, 34060, Montpellier, France
| | - Kevin Garcia
- Department of Biology and Microbiology, South Dakota State University, Brookings, SD, 57007, USA
- BPMP, Université de Montpellier, CNRS, INRA, SupAgro, 34060, Montpellier, France
| | - Laurie Amenc
- Eco & Sols, Université de Montpellier, CIRAD, INRA, IRD, Montpellier SupAgro, 34060, Montpellier, France
| | - Camille Rivard
- CEPIA, INRA, 44300, Nantes, France
- Synchrotron SOLEIL, 91190, Gif-sur-Yvette, France
| | - Jeanne Doré
- LEM, CNRS, INRA, VetAgro Sup, UCBL, Université de Lyon, 69622, Villeurbanne, France
| | - Carlos Trives-Segura
- Eco & Sols, Université de Montpellier, CIRAD, INRA, IRD, Montpellier SupAgro, 34060, Montpellier, France
| | - Wojciech Szponarski
- BPMP, Université de Montpellier, CNRS, INRA, SupAgro, 34060, Montpellier, France
| | - Sylvie Russet
- Eco & Sols, Université de Montpellier, CIRAD, INRA, IRD, Montpellier SupAgro, 34060, Montpellier, France
| | - Yoan Baeza
- Eco & Sols, Université de Montpellier, CIRAD, INRA, IRD, Montpellier SupAgro, 34060, Montpellier, France
| | | | - Gilles Gay
- LEM, CNRS, INRA, VetAgro Sup, UCBL, Université de Lyon, 69622, Villeurbanne, France
| | | | - Claude Plassard
- Eco & Sols, Université de Montpellier, CIRAD, INRA, IRD, Montpellier SupAgro, 34060, Montpellier, France
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5
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Raina JB, Clode PL, Cheong S, Bougoure J, Kilburn MR, Reeder A, Forêt S, Stat M, Beltran V, Thomas-Hall P, Tapiolas D, Motti CM, Gong B, Pernice M, Marjo CE, Seymour JR, Willis BL, Bourne DG. Subcellular tracking reveals the location of dimethylsulfoniopropionate in microalgae and visualises its uptake by marine bacteria. eLife 2017; 6. [PMID: 28371617 PMCID: PMC5380433 DOI: 10.7554/elife.23008] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2016] [Accepted: 03/02/2017] [Indexed: 11/30/2022] Open
Abstract
Phytoplankton-bacteria interactions drive the surface ocean sulfur cycle and local climatic processes through the production and exchange of a key compound: dimethylsulfoniopropionate (DMSP). Despite their large-scale implications, these interactions remain unquantified at the cellular-scale. Here we use secondary-ion mass spectrometry to provide the first visualization of DMSP at sub-cellular levels, tracking the fate of a stable sulfur isotope (34S) from its incorporation by microalgae as inorganic sulfate to its biosynthesis and exudation as DMSP, and finally its uptake and degradation by bacteria. Our results identify for the first time the storage locations of DMSP in microalgae, with high enrichments present in vacuoles, cytoplasm and chloroplasts. In addition, we quantify DMSP incorporation at the single-cell level, with DMSP-degrading bacteria containing seven times more 34S than the control strain. This study provides an unprecedented methodology to label, retain, and image small diffusible molecules, which can be transposable to other symbiotic systems. DOI:http://dx.doi.org/10.7554/eLife.23008.001 Sulfur is an essential element for many organisms and environmental processes. Every year, organisms including microalgae produce more than one billion tons of a sulfur-containing compound called DMSP. Some of this DMSP is released into seawater, where it acts as a key nutrient for microscopic organisms and as a foraging cue to attract fish. DMSP is also the precursor of a gas that helps to form clouds. Despite DMSP’s potential large-scale effects, it is still not clear what role it plays in the organisms that produce it, or how it is transferred from the microalgae that produce it to the bacteria that use it. It is thought that DMSP could potentially protect the cells from sudden changes in the amount of salt in the seawater (salinity) or from other damage, such as oxidative stress – a build-up of harmful chemicals inside cells. In a controlled setting using artificial seawater, Raina et al. used high-resolution imaging and chemical analysis to track the journey of DMSP from microalgae to recipient bacteria. The results show that similar to land plants, algae store DMSP in the compartments that regulate cell pressure and photosynthesis. The presence of DMSP in these locations also supports its proposed role in protecting cells from changes in salinity or oxidative damage. A future step will be to identify the genes involved in producing DMSP in microalgae. This knowledge could be used to create mutants that are either incapable of producing this molecule or that overproduce it. In combination with the high-resolution imaging techniques described here, this will allow researchers to fully understand the role that DMSP plays in these organisms. DOI:http://dx.doi.org/10.7554/eLife.23008.002
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Affiliation(s)
- Jean-Baptiste Raina
- AIMS@JCU, James Cook University, Townsville, Australia.,Australian Institute of Marine Science, Townsville, Australia.,Climate Change Cluster, University of Technology Sydney, Sydney, Australia.,ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Australia.,College of Science and Engineering, James Cook University, Townsville, Australia
| | - Peta L Clode
- The Centre for Microscopy Characterisation and Analysis, The University of Western Australia, Crawley, Australia.,Oceans Institute, The University of Western Australia, Crawley, Australia
| | - Soshan Cheong
- Mark Wainwright Analytical Centre, University of New South Wales, Kensington, Australia
| | - Jeremy Bougoure
- The Centre for Microscopy Characterisation and Analysis, The University of Western Australia, Crawley, Australia.,School of Earth and Environment, The University of Western Australia, Crawley, Australia
| | - Matt R Kilburn
- The Centre for Microscopy Characterisation and Analysis, The University of Western Australia, Crawley, Australia
| | - Anthony Reeder
- The Centre for Microscopy Characterisation and Analysis, The University of Western Australia, Crawley, Australia
| | - Sylvain Forêt
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Australia.,Research School of Biology, Australian National University, Canberra, Australia
| | - Michael Stat
- Trace and Environmental DNA Laboratory, Department of Environment and Agriculture, Curtin University, Perth, Australia
| | - Victor Beltran
- Australian Institute of Marine Science, Townsville, Australia
| | | | - Dianne Tapiolas
- Australian Institute of Marine Science, Townsville, Australia
| | - Cherie M Motti
- AIMS@JCU, James Cook University, Townsville, Australia.,Australian Institute of Marine Science, Townsville, Australia
| | - Bill Gong
- Mark Wainwright Analytical Centre, University of New South Wales, Kensington, Australia
| | - Mathieu Pernice
- Climate Change Cluster, University of Technology Sydney, Sydney, Australia
| | - Christopher E Marjo
- Mark Wainwright Analytical Centre, University of New South Wales, Kensington, Australia
| | - Justin R Seymour
- Climate Change Cluster, University of Technology Sydney, Sydney, Australia
| | - Bette L Willis
- AIMS@JCU, James Cook University, Townsville, Australia.,ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Australia.,College of Science and Engineering, James Cook University, Townsville, Australia
| | - David G Bourne
- Australian Institute of Marine Science, Townsville, Australia.,College of Science and Engineering, James Cook University, Townsville, Australia
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6
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Torres-Aquino M, Becquer A, Le Guernevé C, Louche J, Amenc LK, Staunton S, Quiquampoix H, Plassard C. The host plant Pinus pinaster exerts specific effects on phosphate efflux and polyphosphate metabolism of the ectomycorrhizal fungus Hebeloma cylindrosporum: a radiotracer, cytological staining and 31 P NMR spectroscopy study. PLANT, CELL & ENVIRONMENT 2017; 40:190-202. [PMID: 27743400 DOI: 10.1111/pce.12847] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Revised: 10/06/2016] [Accepted: 10/07/2016] [Indexed: 05/23/2023]
Abstract
Ectomycorrhizal (ECM) association can improve plant phosphorus (P) nutrition. Polyphosphates (polyP) synthesized in distant fungal cells after P uptake may contribute to P supply from the fungus to the host plant if they are hydrolyzed to phosphate in ECM roots then transferred to the host plant when required. In this study, we addressed this hypothesis for the ECM fungus Hebeloma cylindrosporum grown in vitro and incubated without plant or with host (Pinus pinaster) and non-host (Zea mays) plants, using an experimental system simulating the symbiotic interface. We used 32 P labelling to quantify P accumulation and P efflux and in vivo and in vitro nuclear magnetic resonance (NMR) spectroscopy and cytological staining to follow the fate of fungal polyP. Phosphate supply triggered a massive P accumulation as newly synthesized long-chain polyP in H. cylindrosporum if previously grown under P-deficient conditions. P efflux from H. cylindrosporum towards the roots was stimulated by both host and non-host plants. However, the host plant enhanced 32 P release compared with the non-host plant and specifically increased the proportion of short-chain polyP in the interacting mycelia. These results support the existence of specific host plant effects on fungal P metabolism able to provide P in the apoplast of ectomycorrhizal roots.
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Affiliation(s)
- Margarita Torres-Aquino
- INRA, UMR Eco&Sols, 2 place Viala, 34060 CEDEX 1, Montpellier, France
- Colegio de Postgraduados, Campus San Luis Potosí, Agustín de Iturbide N 73, CP 78600, San Luis Potosí, Mexico
| | - Adeline Becquer
- INRA, UMR Eco&Sols, 2 place Viala, 34060 CEDEX 1, Montpellier, France
| | - Christine Le Guernevé
- INRA, UMR SPO (1083) Sciences pour l'Oenologie, 2 place Viala, 34060 CEDEX 1, Montpellier, France
| | - Julien Louche
- INRA, UMR Eco&Sols, 2 place Viala, 34060 CEDEX 1, Montpellier, France
| | - Laurie K Amenc
- INRA, UMR Eco&Sols, 2 place Viala, 34060 CEDEX 1, Montpellier, France
| | - Siobhan Staunton
- INRA, UMR Eco&Sols, 2 place Viala, 34060 CEDEX 1, Montpellier, France
| | - Hervé Quiquampoix
- INRA, UMR Eco&Sols, 2 place Viala, 34060 CEDEX 1, Montpellier, France
| | - Claude Plassard
- INRA, UMR Eco&Sols, 2 place Viala, 34060 CEDEX 1, Montpellier, France
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7
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Wallander H, Pallon J. Temporal changes in the elemental composition ofRhizopogonrhizomorphs during colonization of patches with fresh organic matter or acid-washed sand. Mycologia 2017. [DOI: 10.1080/15572536.2006.11832804] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Håkan Wallander
- Department of Microbial Ecology, University of Lund, Ecology Building, SE-223 62 Lund, Sweden
| | - Jan Pallon
- Department of Nuclear Physics, University of Lund, P.O. Box 118, SE-221 00 Lund, Sweden
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8
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Comensoli L, Bindschedler S, Junier P, Joseph E. Iron and Fungal Physiology: A Review of Biotechnological Opportunities. ADVANCES IN APPLIED MICROBIOLOGY 2017; 98:31-60. [PMID: 28189154 DOI: 10.1016/bs.aambs.2016.11.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Iron is an essential inorganic micronutrient. Because of its low toxicity only a few studies have dealt with the importance of iron in fungal physiology. Most of the studies published so far focus on iron sequestration by animal fungal pathogens, iron uptake by mycorrhizal fungi, or iron redox activities by fungal wood degraders. However, a general overview on the relationship between fungal physiology and iron is still lacking. In this review we present a summary of the types of physiological activities that participate in iron homeostasis in fungi and how these activities can be used for the development of original biotechnological applications in relationship to iron-containing matrices. Concrete examples of biotechnological applications involving iron and fungi are also discussed. In the last part, a specific research project in biotechnology focusing on the use of fungi for the conservation of archaeological objects in iron is described in detail. This project aims at developing a new conservation-restoration method to preserve archaeological iron artifacts exploiting the ability of fungi to transform and uptake iron. Preliminary results obtained in this project regarding iron-reduction, iron uptake, and biogenic formation of iron minerals are presented and discussed.
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Affiliation(s)
- L Comensoli
- University of Neuchâtel, Neuchâtel, Switzerland
| | | | - P Junier
- University of Neuchâtel, Neuchâtel, Switzerland
| | - E Joseph
- University of Neuchâtel, Neuchâtel, Switzerland; Haute Ecole Arc Conservation-Restauration, Neuchâtel, Switzerland
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9
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Kulakovskaya TV, Lichko LP, Ryazanova LP. Diversity of phosphorus reserves in microorganisms. BIOCHEMISTRY (MOSCOW) 2015; 79:1602-14. [PMID: 25749167 DOI: 10.1134/s0006297914130100] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Phosphorus compounds are indispensable components of the Earth's biomass metabolized by all living organisms. Under excess of phosphorus compounds in the environment, microorganisms accumulate reserve phosphorus compounds that are used under phosphorus limitation. These compounds vary in their structure and also perform structural and regulatory functions in microbial cells. The most common phosphorus reserve in microorganism is inorganic polyphosphates, but in some archae and bacteria insoluble magnesium phosphate plays this role. Some yeasts produce phosphomannan as a phosphorus reserve. This review covers also other topics, i.e. accumulation of phosphorus reserves under nutrient limitation, phosphorus reserves in activated sludge, mycorrhiza, and the role of mineral phosphorus compounds in mammals.
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Affiliation(s)
- T V Kulakovskaya
- Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia.
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10
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Garcia K, Zimmermann SD. The role of mycorrhizal associations in plant potassium nutrition. FRONTIERS IN PLANT SCIENCE 2014; 5:337. [PMID: 25101097 PMCID: PMC4101882 DOI: 10.3389/fpls.2014.00337] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 06/25/2014] [Indexed: 05/05/2023]
Abstract
Potassium (K(+)) is one of the most abundant elements of soil composition but it's very low availability limits plant growth and productivity of ecosystems. Because this cation participates in many biological processes, its constitutive uptake from soil solution is crucial for the plant cell machinery. Thus, the understanding of strategies responsible of K(+) nutrition is a major issue in plant science. Mycorrhizal associations occurring between roots and hyphae of underground fungi improve hydro-mineral nutrition of the majority of terrestrial plants. The contribution of this mutualistic symbiosis to the enhancement of plant K(+) nutrition is not well understood and poorly studied so far. This mini-review examines the current knowledge about the impact of both arbuscular mycorrhizal and ectomycorrhizal symbioses on the transfer of K(+) from the soil to the plants. A model summarizing plant and fungal transport systems identified and hypothetically involved in K(+) transport is proposed. In addition, some data related to benefits for plants provided by the improvement of K(+) nutrition thanks to mycorrhizal symbioses are presented.
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Affiliation(s)
| | - Sabine D. Zimmermann
- Biochimie et Physiologie Moléculaire des Plantes, UMR 5004 CNRS/INRA/SupAgro/UM2Montpellier, France
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11
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Benito B, González-Guerrero M. Unravelling potassium nutrition in ectomycorrhizal associations. THE NEW PHYTOLOGIST 2014; 201:707-709. [PMID: 24400896 DOI: 10.1111/nph.12659] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Affiliation(s)
- Begoña Benito
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid, Madrid, Spain
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12
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Garcia K, Delteil A, Conéjéro G, Becquer A, Plassard C, Sentenac H, Zimmermann S. Potassium nutrition of ectomycorrhizal Pinus pinaster: overexpression of the Hebeloma cylindrosporum HcTrk1 transporter affects the translocation of both K(+) and phosphorus in the host plant. THE NEW PHYTOLOGIST 2014; 201:951-960. [PMID: 24279702 DOI: 10.1111/nph.12603] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Accepted: 10/16/2013] [Indexed: 05/07/2023]
Abstract
Mycorrhizal associations are known to improve the hydro-mineral nutrition of their host plants. However, the importance of mycorrhizal symbiosis for plant potassium nutrition has so far been poorly studied. We therefore investigated the impact of the ectomycorrhizal fungus Hebeloma cylindrosporum on the potassium nutrition of Pinus pinaster and examined the involvement of the fungal potassium transporter HcTrk1. HcTrk1 transcripts and proteins were localized in ectomycorrhizas using in situ hybridization and EGFP translational fusion constructs. Importantly, an overexpression strategy was performed on a H. cylindrosporum endogenous gene in order to dissect the role of this transporter. The potassium nutrition of mycorrhizal pine plants was significantly improved under potassium-limiting conditions. Fungal strains overexpressing HcTrk1 reduced the translocation of potassium and phosphorus from the roots to the shoots of inoculated plants in mycorrhizal experiments. Furthermore, expression of HcTrk1 and the phosphate transporter HcPT1.1 were reciprocally linked to the external inorganic phosphate and potassium availability. The development of these approaches provides a deeper insight into the role of ectomycorrhizal symbiosis on host plant K(+) nutrition and in particular, the K(+) transporter HcTrk1. The work augments our knowledge of the link between potassium and phosphorus nutrition via the mycorrhizal pathway.
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Affiliation(s)
- Kevin Garcia
- Biochimie et Physiologie Moléculaire des Plantes, UMR 5004 CNRS/INRA/SupAgro/UM2, Campus INRA/SupAgro, 2 Place Viala, 34060, Montpellier Cedex 2, France
| | - Amandine Delteil
- Biochimie et Physiologie Moléculaire des Plantes, UMR 5004 CNRS/INRA/SupAgro/UM2, Campus INRA/SupAgro, 2 Place Viala, 34060, Montpellier Cedex 2, France
| | - Geneviève Conéjéro
- Biochimie et Physiologie Moléculaire des Plantes, UMR 5004 CNRS/INRA/SupAgro/UM2, Campus INRA/SupAgro, 2 Place Viala, 34060, Montpellier Cedex 2, France
- Plateforme Histocytologie et Imagerie Cellulaire Végétale, INRA-CIRAD, 34398, Montpellier, France
| | - Adeline Becquer
- INRA, UMR 1222 Eco&Sols, 2 Place Viala, 34060, Montpellier Cedex 2, France
| | - Claude Plassard
- INRA, UMR 1222 Eco&Sols, 2 Place Viala, 34060, Montpellier Cedex 2, France
| | - Hervé Sentenac
- Biochimie et Physiologie Moléculaire des Plantes, UMR 5004 CNRS/INRA/SupAgro/UM2, Campus INRA/SupAgro, 2 Place Viala, 34060, Montpellier Cedex 2, France
| | - Sabine Zimmermann
- Biochimie et Physiologie Moléculaire des Plantes, UMR 5004 CNRS/INRA/SupAgro/UM2, Campus INRA/SupAgro, 2 Place Viala, 34060, Montpellier Cedex 2, France
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Wallander H, Mahmood S, Hagerberg D, Johansson L, Pallon J. Elemental composition of ectomycorrhizal mycelia identified by PCR-RFLP analysis and grown in contact with apatite or wood ash in forest soil. FEMS Microbiol Ecol 2012; 44:57-65. [PMID: 19719651 DOI: 10.1111/j.1574-6941.2003.tb01090.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Abstract The aim of this study was to identify ectomycorrhizal species with a potential to release elements from apatite and wood ash and accumulate them in the mycelia. Fungal rhizomorphs and mycelia were sampled from sand-filled mesh bags with or without amendment of apatite or wood ash. The mesh bags were buried in forest soil in the field for 13 or 24 months. Elemental composition of the samples was analyzed with particle-induced X-ray emission and the fungus was identified by polymerase chain reaction-restriction fragment length polymorphism analysis of the ITS-region of ribosomal DNA. The majority of rhizomorphs and mycelia collected from the mesh bags were of mycorrhizal origin with Paxillus involutus being the most common species (31%). Other identified species were Thelephora terrestris, Suillus granulatus and Tylospora fibillosa. S. granulatus contained 3-15 times more K (3 mg g(-1)) than the other species and had large calcium-rich crystals deposited on the surface of rhizomorphs when grown in contact with apatite. P. involutus contained the largest amount of Ca (2-7 mg g(-1)). Wood ash addition increased the amount of Ti, Mn and Pb in the rhizomorphs while apatite addition increased the amount of Ca in the rhizomorphs. The high concentration of K in S. granulatus rhizomorphs suggests that this fungus is a good accumulator of K while P. involutus appeared to accumulate heavy metals originating from wood ash.
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Affiliation(s)
- Håkan Wallander
- Department of Microbial Ecology, University of Lund, Ecology Building, 223 62 Lund, Sweden
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14
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Bowman BJ, Abreu S, Margolles-Clark E, Draskovic M, Bowman EJ. Role of four calcium transport proteins, encoded by nca-1, nca-2, nca-3, and cax, in maintaining intracellular calcium levels in Neurospora crassa. EUKARYOTIC CELL 2011; 10:654-61. [PMID: 21335528 PMCID: PMC3127652 DOI: 10.1128/ec.00239-10] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Accepted: 02/14/2011] [Indexed: 11/20/2022]
Abstract
We have examined the distribution of calcium in Neurospora crassa and investigated the role of four predicted calcium transport proteins. The results of cell fractionation experiments showed 4% of cellular calcium in mitochondria, approximately 11% in a dense vacuolar fraction, 40% in an insoluble form that copurifies with microsomes, and 40% in a high-speed supernatant, presumably from large vacuoles that had broken. Strains lacking NCA-1, a SERCA-type Ca(2+)-ATPase, or NCA-3, a PMC-type Ca(2+)-ATPase, had no obvious defects in growth or distribution of calcium. A strain lacking NCA-2, which is also a PMC-type Ca(2+)-ATPase, grew slowly in normal medium and was unable to grow in high concentrations of calcium tolerated by the wild type. Furthermore, when grown in normal concentrations of calcium (0.68 mM), this strain accumulated 4- to 10-fold more calcium than other strains, elevated in all cell fractions. The data suggest that NCA-2 functions in the plasma membrane to pump calcium out of the cell. In this way, it resembles the PMC-type enzymes of animal cells, not the Pmc1p enzyme in Saccharomyces cerevisiae that resides in the vacuole. Strains lacking the cax gene, which encodes a Ca(2+)/H(+) exchange protein in vacuolar membranes, accumulate very little calcium in the dense vacuolar fraction but have normal levels of calcium in other fractions. The cax knockout strain has no other observable phenotypes. These data suggest that "the vacuole" is heterogeneous and that the dense vacuolar fraction contains an organelle that is dependent upon the CAX transporter for accumulation of calcium, while other components of the vacuolar system have multiple calcium transporters.
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Affiliation(s)
- Barry J Bowman
- Department of Molecular, Cell, and Developmental Biology, University of California, Santa Cruz, CA 95064, USA.
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15
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Olsson PA, Hammer EC, Wallander H, Pallon J. Phosphorus availability influences elemental uptake in the mycorrhizal fungus Glomus intraradices, as revealed by particle-induced X-ray emission analysis. Appl Environ Microbiol 2008; 74:4144-8. [PMID: 18469133 PMCID: PMC2446498 DOI: 10.1128/aem.00376-08] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2008] [Accepted: 05/04/2008] [Indexed: 11/20/2022] Open
Abstract
We investigated element accumulation in the arbuscular mycorrhizal fungus Glomus intraradices. Fungal spores and mycelia growing in monoxenic cultures were analyzed. The elemental composition was quantified using particle-induced X-ray emission (PIXE) in combination with scanning transmission ion microscopy. In the spores, Ca and Fe were associated mainly with the spore wall, while P and K showed patchy distributions and their concentrations were correlated. Excess of P in the hyphal growth medium increased the P and Si concentrations in spores and increased the K/Ca ratio in spores. Increased P availability decreased the concentration of Zn and Mn in spores. We concluded that the availability of P influences the uptake and accumulation of several elements in spores. It is demonstrated that PIXE analysis is a powerful tool for quantitative analysis of elemental accumulation in fungal mycelia.
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Affiliation(s)
- Pål Axel Olsson
- Department of Plant Ecology and Systematics, Ecology Building, Lund University, SE-223 62 Lund, Sweden.
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16
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González-Guerrero M, Melville LH, Ferrol N, Lott JNA, Azcón-Aguilar C, Peterson RL. Ultrastructural localization of heavy metals in the extraradical mycelium and spores of the arbuscular mycorrhizal fungus Glomus intraradices. Can J Microbiol 2008; 54:103-10. [PMID: 18388979 DOI: 10.1139/w07-119] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Arbuscular mycorrhizal fungi, obligate symbionts of most plant species, are able to accumulate heavy metals, thereby, protecting plants from metal toxicity. In this study, the ultrastructural localization of Zn, Cu, and Cd in the extraradical mycelium and spores of the arbuscular mycorrhizal fungus Glomus intraradices grown in monoxenic cultures was investigated. Zinc, Cu, or Cd was applied to the extraradical mycelium to final concentrations of 7.5, 5.0, or 0.45 mmol/L, respectively. Samples were collected at time 0, 8 h, and 7 days after metal application and were prepared for rapid freezing and freeze substitution. Metal content in different subcellular locations (wall, cytoplasm, and vacuoles), both in hyphae and spores, was determined by energy-dispersive X-ray spectroscopy. In all treatments and fungal structures analysed, heavy metals accumulated mainly in the fungal cell wall and in the vacuoles, while minor changes in metal concentrations were detected in the cytoplasm. Incorporation of Zn into the fungus occurred during the first 8 h after metal addition with no subsequent accumulation. On the other hand, Cu steadily accumulated in the spore vacuoles over time, whereas Cd steadily accumulated in the hyphal vacuoles. These results suggest that binding of metals to the cell walls and compartmentalization in vacuoles may be essential mechanisms for metal detoxification.
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Affiliation(s)
- Manuel González-Guerrero
- Departamento de Microbiologia del Suelo y Sistemas Simbioticos, Estacion Experimental del Zaidin, Consejo Supertableior de Investigaciones Cientificas (CSIC), Profesor Albareda 1, 18008 Granada, Spain.
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Kuga Y, Saito K, Nayuki K, Peterson RL, Saito M. Ultrastructure of rapidly frozen and freeze-substituted germ tubes of an arbuscular mycorrhizal fungus and localization of polyphosphate. THE NEW PHYTOLOGIST 2008; 178:189-200. [PMID: 18194149 DOI: 10.1111/j.1469-8137.2007.02345.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
In arbuscular mycorrhizas (AM), the supply of phosphorus from the fungi is one of the most important benefits to the host plant. Here we describe for the first time the ultrastructure and polyphosphate (poly P) distribution in rapidly frozen and freeze-substituted germ tubes of the AM fungus Gigaspora margarita. At the ultrastructural level, phosphorus distribution was analysed using energy-filtering transmission electron microscopy, and poly P was detected using an enzyme-affinity method. Semithin sections and live cells were also stained with 4',6-diamidino-2-phenylindole, which is not specific but fluoresces yellow when viewed under UV irradiation by binding with poly P. The cryotechnique method showed that extensive elongate ellipsoid vacuoles containing a uniform electron-opaque material occupied most of the cell volume. Combining the results of multiple methods revealed that poly P was localized in a dispersed form in vacuoles and in the outer fungal cell wall. These results show the significant potential of AM fungi for phosphorus storage based on its localization in the extensive complement of vacuoles in thick hyphae. The mechanism of translocation of poly P in tubular vacuoles, and the role of poly P in the cell wall, need to be elucidated.
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Affiliation(s)
- Yukari Kuga
- Department of Food Production Science, Faculty of Agriculture, Shinshu University, Minami-minowa, Nagano 399-4598, Japan
| | - Katsuharu Saito
- Department of Food Production Science, Faculty of Agriculture, Shinshu University, Minami-minowa, Nagano 399-4598, Japan
| | - Keiichiro Nayuki
- Department of Food Production Science, Faculty of Agriculture, Shinshu University, Minami-minowa, Nagano 399-4598, Japan
| | - R Larry Peterson
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Masanori Saito
- Department of Environmental Chemistry, National Institute for Agro-Environmental Sciences, Tsukuba, Ibaraki 305-8604, Japan
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18
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Growth media effects on morphology and 17β-HSD activity in the fungusCurvularia lunata. ANN MICROBIOL 2007. [DOI: 10.1007/bf03175366] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Affiliation(s)
- Michael W Hess
- Division of Histology and Embryology, Innsbruck Medical University, A-6020 Innsbruck, Austria
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Saito K, Kuga-Uetake Y, Saito M, Peterson RL. Vacuolar localization of phosphorus in hyphae ofPhialocephala fortinii, a dark septate fungal root endophyte. Can J Microbiol 2006; 52:643-50. [PMID: 16917520 DOI: 10.1139/w06-018] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Phialocephala fortinii is a dark septate fungal endophyte that colonizes roots of many host species. Its effect on plant growth varies from being pathogenic to beneficial. The basic biology of this species has received little research, and thus the main objectives of this study were to determine cytological features of hyphae, including the nature of the vacuolar system, and whether polyphosphate was present in vacuoles. Both living hyphae and hyphae that had been rapidly frozen and freeze substituted before embedding were studied. A complex system of vacuoles, including a motile tubular vacuolar system, elongated vacuoles, and spherical vacuoles, was demonstrated in living hyphae by the fluorescent probe Oregon Green 488 carboxylic acid diacetate, using laser scanning confocal microscopy. The motile tubular vacuolar system was more prevalent at the hyphal tip than in more distal regions, whereas elongated vacuoles and spherical vacuoles were more abundant distal to the tip. All vacuoles contained polyphosphate as shown by labelling embedded samples with recombinant polyphosphate binding domain of Escherichia coli exopolyphosphatase, containing Xpress tag at the N-terminal end, followed by anti-Xpress antibody and a secondary antibody conjugated either to a fluorescent probe for laser scanning confocal microscopy or colloidal gold for transmission electron microscopy. The polyphosphate was dispersed in vacuoles. This was confirmed by staining embedded samples with 4′,6-diamidino-2-phenylindole and viewing with UV light using epifluorescence microscopy. These cytological methods showed that the tubular vacuolar system had lower concentrations of polyphosphate than the spherical vacuoles. Lipid bodies were present around vacuoles.Key words: Phialocephala, motile tubular vacuoles, vacuoles, polyphosphate, lipid.
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Affiliation(s)
- Katsuharu Saito
- Department of Grassland Ecology, National Institute of Livestock and Grassland Science, Japan.
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Saito K, Ohtomo R, Kuga-Uetake Y, Aono T, Saito M. Direct labeling of polyphosphate at the ultrastructural level in Saccharomyces cerevisiae by using the affinity of the polyphosphate binding domain of Escherichia coli exopolyphosphatase. Appl Environ Microbiol 2005; 71:5692-701. [PMID: 16204477 PMCID: PMC1266008 DOI: 10.1128/aem.71.10.5692-5701.2005] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Inorganic polyphosphate (polyP) is a linear polymer of orthophosphate and has many biological functions in prokaryotic and eukaryotic organisms. To investigate polyP localization, we developed a novel technique using the affinity of the recombinant polyphosphate binding domain (PPBD) of Escherichia coli exopolyphosphatase to polyP. An epitope-tagged PPBD was expressed and purified from E. coli. Equilibrium binding assay of PPBD revealed its high affinity for long-chain polyP and its weak affinity for short-chain polyP and nucleic acids. To directly demonstrate polyP localization in Saccharomyces cerevisiae on resin sections prepared by rapid freezing and freeze-substitution, specimens were labeled with PPBD containing an epitope tag and then the epitope tag was detected by an indirect immunocytochemical method. A goat anti-mouse immunoglobulin G antibody conjugated with Alexa 488 for laser confocal microscopy or with colloidal gold for transmission electron microscopy was used. When the S. cerevisiae was cultured in yeast extract-peptone-dextrose medium (10 mM phosphate) for 10 h, polyP was distributed in a dispersed fashion in vacuoles in successfully cryofixed cells. A few polyP signals of the labeling were sometimes observed in cytosol around vacuoles with electron microscopy. Under our experimental conditions, polyP granules were not observed. Therefore, it remains unclear whether the method can detect the granule form. The method directly demonstrated the localization of polyP at the electron microscopic level for the first time and enabled the visualization of polyP localization with much higher specificity and resolution than with other conventional methods.
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Affiliation(s)
- Katsuharu Saito
- Department of Environmental Chemistry, National Institute for Agro-Environmental Sciences, 3-1-3 Kannondai, Tsukuba, Ibaraki 305-8604, Japan
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22
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Colpaert JV, Adriaensen K, Muller LAH, Lambaerts M, Faes C, Carleer R, Vangronsveld J. Element profiles and growth in Zn-sensitive and Zn-resistant Suilloid fungi. MYCORRHIZA 2005; 15:628-634. [PMID: 16133247 DOI: 10.1007/s00572-005-0009-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2004] [Revised: 05/31/2005] [Indexed: 05/04/2023]
Abstract
Zn pollution has triggered evolution for adaptive Zn tolerance in populations of Suilloid ectomycorrhizal fungi. The objectives of this study were to determine differential physiological responses that are linked to the Zn tolerance trait and to obtain more insight in the general mechanism responsible for the differential growth in Zn-enriched medium. Therefore, we identified intrinsic growth rates and element profiles in Zn-sensitive and Zn-tolerant genotypes. Isolates from Zn-polluted and unpolluted sites were exposed in vitro to increasing Zn(2+) stress. The Zn concentration which inhibits growth by 50% (EC(50)) was determined, and element (Zn, Fe, Mn, Cu, Mg, Ca and P) profiles in the mycelia were analysed. The intraspecific variation in growth rate and nutrient content of the in vitro grown mycelia is great and was not reduced in Zn-tolerant populations. The Zn resistance was not correlated to the intrinsic mycelial growth rate of the isolates or to the concentrations of the elements analysed, except for Zn. At low external Zn, Zn-resistant genotypes had lower Zn concentrations than sensitive isolates. At high external Zn, the differential Zn accumulation pattern between resistant and sensitive isolates became very prominent. Zn-exclusion mechanisms are most likely involved in the naturally selected adaptive Zn resistance. Other mechanisms of Zn detoxification such as sequestration of Zn on cell wall compounds or intracellular chelation and/or compartmentation are probably active but cannot explain the differential Zn sensitivity of the isolates.
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Affiliation(s)
- Jan V Colpaert
- Center for Environmental Sciences, Environmental Biology Group, Hasselt University, Agoralaan, gebouw D, 3590, Diepenbeek, Belgium.
| | - Kristin Adriaensen
- Center for Environmental Sciences, Environmental Biology Group, Hasselt University, Agoralaan, gebouw D, 3590, Diepenbeek, Belgium
| | - Ludo A H Muller
- Center for Environmental Sciences, Environmental Biology Group, Hasselt University, Agoralaan, gebouw D, 3590, Diepenbeek, Belgium
| | - Marc Lambaerts
- Center for Environmental Sciences, Environmental Biology Group, Hasselt University, Agoralaan, gebouw D, 3590, Diepenbeek, Belgium
| | - Christel Faes
- Center for Statistics, Hasselt University, Agoralaan, gebouw D, 3590, Diepenbeek, Belgium
| | - Robert Carleer
- Center for Environmental Sciences, Laboratory of Applied Chemistry, Hasselt University, Agoralaan, gebouw D, 3590, Diepenbeek, Belgium
| | - Jaco Vangronsveld
- Center for Environmental Sciences, Environmental Biology Group, Hasselt University, Agoralaan, gebouw D, 3590, Diepenbeek, Belgium
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Affiliation(s)
- Anne Ashford
- School of Biological ScienceThe University of New South WalesSydney, NSW 2052, Australia(tel +61 29385 2068; fax +61 29385 1558;email )
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Allaway WG, Ashford AE. Motile tubular vacuoles in extramatrical mycelium and sheath hyphae of ectomycorrhizal systems. PROTOPLASMA 2001; 215:218-25. [PMID: 11732061 DOI: 10.1007/bf01280316] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Extramatrical mycelium and outer hyphae of the sheath of Eucalyptus pilularis-Pisolithus tinctorius mycorrhizas contain abundant motile tubular vacuoles which accumulate the carboxyfluorescein analogue Oregon Green 488 carboxylic acid. The fluorochrome accumulates in a system of small vacuoles, tubules, and larger vacuoles, which are interlinked, motile, and pleiomorphic, in external hyphae, cords, and hyphae of the outer sheath. There is often a difference in fluorescence between two neighbouring cells, indicating that the dolipore septum exercises control on the movement of material between cells. Generally the motile tubular vacuole system in mycorrhizas resembles that previously found in isolated mycelium. The majority of fungal cells in the sheath contain no fluorochrome even after long exposure of the mycorrhiza to the solution, but with differential interference optics the cells are clearly seen to be alive and to contain vacuoles resembling those in the outer hyphae. In translocation experiments, long-distance transport of the fluorochrome is slow and slight, or even nonexistent in some cases.
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Affiliation(s)
- W G Allaway
- School of Biological Science, University of New South Wales, Sydney, NSW 2052, Australia
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