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Agarwal R, Gupta M, Sen R, Panchal A, E S N, Raychoudhury R. Investigation into how Odontotermes obesus maintains a predominantly Termitomyces monoculture in their fungus combs suggests a potential partnership with both fungi and bacteria. Commun Biol 2024; 7:1010. [PMID: 39154098 PMCID: PMC11330501 DOI: 10.1038/s42003-024-06708-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Accepted: 08/08/2024] [Indexed: 08/19/2024] Open
Abstract
Fungus-growing termites, like Odontotermes obesus, cultivate Termitomyces as their sole food source on fungus combs which are continuously maintained with foraged plant materials. This necessary augmentation also increases the threat of introducing non-specific fungi capable of displacing Termitomyces. The magnitude of this threat and how termites prevent the invasion of such fungi remain largely unknown. This study identifies these non-specific fungi by establishing the pan-mycobiota of O. obesus from the fungus comb and termite castes. Furthermore, to maximize the identification of such fungi, the mycobiota of the decaying stages of the unattended fungus comb were also assessed. The simultaneous assessment of the microbiota and the mycobiota of these stages identified possible interactions between the fungal and bacterial members of this community. Based on these findings, we propose possible interactions among the crop fungus Termitomyces, the weedy fungus Pseudoxylaria and some bacterial symbiotes. These possibilities were then tested with in vitro interaction assays which suggest that Termitomyces, Pseudoxylaria and certain potential bacterial symbiotes possess anti-fungal capabilities. We propose a multifactorial interaction model of these microbes, under the care of the termites, to explain how their interactions can maintain a predominantly Termitomyces monoculture.
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Affiliation(s)
- Renuka Agarwal
- Department of Biological Sciences, Indian Institute of Science Education and Research Mohali IISER Mohali, Knowledge City, Manauli, Punjab, India
| | - Manisha Gupta
- Department of Biological Sciences, Indian Institute of Science Education and Research Mohali IISER Mohali, Knowledge City, Manauli, Punjab, India
| | - Ruchira Sen
- PG Department of Zoology, Sri Guru Gobind Singh College, Chandigarh, India
| | - Aanchal Panchal
- Department of Biological Sciences, Indian Institute of Science Education and Research Mohali IISER Mohali, Knowledge City, Manauli, Punjab, India
| | - Nimisha E S
- Department of Biological Sciences, Indian Institute of Science Education and Research Mohali IISER Mohali, Knowledge City, Manauli, Punjab, India
| | - Rhitoban Raychoudhury
- Department of Biological Sciences, Indian Institute of Science Education and Research Mohali IISER Mohali, Knowledge City, Manauli, Punjab, India.
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Ahmad F, Yang G, Zhu Y, Poulsen M, Li W, Yu T, Mo J. Tripartite Symbiotic Digestion of Lignocellulose in the Digestive System of a Fungus-Growing Termite. Microbiol Spectr 2022; 10:e0123422. [PMID: 36250871 PMCID: PMC9769757 DOI: 10.1128/spectrum.01234-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 09/23/2022] [Indexed: 01/05/2023] Open
Abstract
Fungus-growing termites are efficient in degrading and digesting plant substrates, achieved through the engagement of symbiotic gut microbiota and lignocellulolytic Termitomyces fungi cultivated for protein-rich food. Insights into where specific plant biomass components are targeted during the decomposition process are sparse. In this study, we performed several analytical approaches on the fate of plant biomass components and did amplicon sequencing of the 16S rRNA gene to investigate the lignocellulose digestion in the symbiotic system of the fungus-growing termite Odontotermes formosanus (Shiraki) and to compare bacterial communities across the different stages in the degradation process. We observed a gradual reduction of lignocellulose components throughout the process. Our findings support that the digestive tract of young workers initiates the degradation of lignocellulose but leaves most of the lignin, hemicellulose, and cellulose, which enters the fresh fungus comb, where decomposition primarily occurs. We found a high diversity and quantity of monomeric sugars in older parts of the fungus comb, indicating that the decomposition of lignocellulose enriches the old comb with sugars that can be utilized by Termitomyces and termite workers. Amplicon sequencing of the 16S rRNA gene showed clear differences in community composition associated with the different stages of plant biomass decomposition which could work synergistically with Termitomyces to shape the digestion process. IMPORTANCE Fungus-farming termites have a mutualist association with fungi of the genus Termitomyces and gut microbiota to support the nearly complete decomposition of lignocellulose to gain access to nutrients. This elaborate strategy of plant biomass digestion makes them ecologically successful dominant decomposers in (sub)tropical Old World ecosystems. We employed acid detergent fiber analysis, high-performance anion-exchange chromatography (HPAEC), high-performance liquid chromatography (HPLC), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), pyrolysis gas chromatography-mass spectrometry (Py-GC-MS), and amplicon sequencing of the 16S rRNA gene to examine which lignocellulose components were digested and which bacteria were abundant throughout the decomposition process. Our findings suggest that although the first gut passage initiates lignocellulose digestion, the most prominent decomposition occurs within the fungus comb. Moreover, distinct bacterial communities were associated with different stages of decomposition, potentially contributing to the breakdown of particular plant components.
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Affiliation(s)
- Farhan Ahmad
- Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Zhejiang, People’s Republic of China
- Entomology Section, Central Cotton Research Institute, Multan, Punjab, Pakistan
- Entomology Section, Central Cotton Research Institute, Sakrand, Shaheed Benazirabad, Sindh, Pakistan
| | - Guiying Yang
- Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Zhejiang, People’s Republic of China
| | - Yaning Zhu
- Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Zhejiang, People’s Republic of China
| | - Michael Poulsen
- Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Copenhagen East, Denmark
| | - Wuhan Li
- Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Zhejiang, People’s Republic of China
| | - Ting Yu
- Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Zhejiang, People’s Republic of China
| | - Jianchu Mo
- Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Zhejiang, People’s Republic of China
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Tan M, Li Y, Xu J, Yan S, Jiang D. Effects of Arbuscular Mycorrhizal Fungi-Colonized Populus alba × P. berolinensis Seedlings on the Microbial and Metabolic Status of Gypsy Moth Larvae. INSECTS 2022; 13:1002. [PMID: 36354825 PMCID: PMC9697668 DOI: 10.3390/insects13111002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Revised: 10/18/2022] [Accepted: 10/26/2022] [Indexed: 06/16/2023]
Abstract
Arbuscular mycorrhizal fungi (AMF) are considered as important biological factors that can affect insect resistance of plants. Herein, we used AMF-poplar seedlings that could either increase or decrease the resistance to gypsy moth larvae, to elucidate the mechanism of mycorrhizal-induced insect resistance/susceptibility at the larval microbial and metabolic levels. Our results found that larval plant consumption and growth were significantly inhibited in the Glomus mossae (GM)-colonized seedlings, whereas they were enhanced in the Glomus intraradices (GI)-colonized seedlings. GM inoculation reduced the beneficial bacteria abundance in the larval gut and inhibited the detoxification and metabolic functions of gut microbiota. However, GI inoculation improved the larval gut environment by decreasing the pathogenic bacteria and activating specific metabolic pathways. Furthermore, GM inoculation triggers a metabolic disorder in the larval fat body, accompanied by the suppression of detoxification and energy production pathways. The levels of differentially accumulated metabolites related to amino acid synthesis and metabolism and exogenous toxin metabolism pathways were significantly increased in the GI group. Taken together, the disadaptation of gypsy moth larvae to leaves of GM-colonized seedlings led to the GM-induced insect resistance in poplar, and to the GI-induced insect susceptibility involved in the improvement of larval gut environment and fat body energy metabolism.
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Affiliation(s)
- Mingtao Tan
- School of Forestry, Northeast Forestry University, Harbin 150040, China
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, Northeast Forestry University, Harbin 150040, China
| | - Yaning Li
- School of Forestry, Northeast Forestry University, Harbin 150040, China
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, Northeast Forestry University, Harbin 150040, China
| | - Jinsheng Xu
- School of Forestry, Northeast Forestry University, Harbin 150040, China
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, Northeast Forestry University, Harbin 150040, China
| | - Shanchun Yan
- School of Forestry, Northeast Forestry University, Harbin 150040, China
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, Northeast Forestry University, Harbin 150040, China
| | - Dun Jiang
- School of Forestry, Northeast Forestry University, Harbin 150040, China
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, Northeast Forestry University, Harbin 150040, China
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Li H, Greening C. Termite-engineered microbial communities of termite nest structures: a new dimension to the extended phenotype. FEMS Microbiol Rev 2022; 46:6631553. [PMID: 35790132 PMCID: PMC9779920 DOI: 10.1093/femsre/fuac034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 07/01/2022] [Indexed: 01/09/2023] Open
Abstract
Termites are a prototypical example of the 'extended phenotype' given their ability to shape their environments by constructing complex nesting structures and cultivating fungus gardens. Such engineered structures provide termites with stable, protected habitats, and nutritious food sources, respectively. Recent studies have suggested that these termite-engineered structures harbour Actinobacteria-dominated microbial communities. In this review, we describe the composition, activities, and consequences of microbial communities associated with termite mounds, other nests, and fungus gardens. Culture-dependent and culture-independent studies indicate that these structures each harbour specialized microbial communities distinct from those in termite guts and surrounding soils. Termites select microbial communities in these structures through various means: opportunistic recruitment from surrounding soils; controlling physicochemical properties of nesting structures; excreting hydrogen, methane, and other gases as bacterial energy sources; and pretreating lignocellulose to facilitate fungal cultivation in gardens. These engineered communities potentially benefit termites by producing antimicrobial compounds, facilitating lignocellulose digestion, and enhancing energetic efficiency of the termite 'metaorganism'. Moreover, mound-associated communities have been shown to be globally significant in controlling emissions of methane and enhancing agricultural fertility. Altogether, these considerations suggest that the microbiomes selected by some animals extend much beyond their bodies, providing a new dimension to the 'extended phenotype'.
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Affiliation(s)
- Hongjie Li
- Corresponding author. State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Key Laboratory of Biotechnology in Plant Protection of Ministry of Agriculture and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo 315211. China. E-mail:
| | - Chris Greening
- Corresponding author. Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia. E-mail:
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Ahmad F, Yang GY, Liang SY, Zhou QH, Gaal HA, Mo JC. Multipartite symbioses in fungus-growing termites (Blattodea: Termitidae, Macrotermitinae) for the degradation of lignocellulose. INSECT SCIENCE 2021; 28:1512-1529. [PMID: 33236502 DOI: 10.1111/1744-7917.12890] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Revised: 10/06/2020] [Accepted: 10/19/2020] [Indexed: 06/11/2023]
Abstract
Fungus-growing termites are among the most successful herbivorous animals and improve crop productivity and soil fertility. A range of symbiotic organisms can be found inside their nests. However, interactions of termites with these symbionts are poorly understood. This review provides detailed information on the role of multipartite symbioses (between termitophiles, termites, fungi, and bacteria) in fungus-growing termites for lignocellulose degradation. The specific functions of each component in the symbiotic system are also discussed. Based on previous studies, we argue that the enzymatic contribution from the host, fungus, and bacteria greatly facilitates the decomposition of complex polysaccharide plant materials. The host-termitophile interaction protects the termite nest from natural enemies and maintains the stability of the microenvironment inside the colony.
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Affiliation(s)
- Farhan Ahmad
- Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Sciences, College of Agricultural and Biotechnology, Zhejiang University, Hangzhou, China
- Entomology Section, Central Cotton Research Institute, Sakrand, Shaheed Benazirabad, Sindh, Pakistan
| | - Gui-Ying Yang
- Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Sciences, College of Agricultural and Biotechnology, Zhejiang University, Hangzhou, China
| | - Shi-You Liang
- Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Sciences, College of Agricultural and Biotechnology, Zhejiang University, Hangzhou, China
| | - Qi-Huan Zhou
- Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Sciences, College of Agricultural and Biotechnology, Zhejiang University, Hangzhou, China
| | - Hassan Ahmed Gaal
- Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Sciences, College of Agricultural and Biotechnology, Zhejiang University, Hangzhou, China
- Department of Entomology, Faculty of Veterinary and Animal Husbandry, Somali National University, Mogadishu, Somalia
| | - Jian-Chu Mo
- Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Sciences, College of Agricultural and Biotechnology, Zhejiang University, Hangzhou, China
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Yang G, Ahmad F, Zhou Q, Guo M, Liang S, Gaal HA, Mo J. Investigation of Physicochemical Indices and Microbial Communities in Termite Fungus-Combs. Front Microbiol 2021; 11:581219. [PMID: 33519727 PMCID: PMC7843810 DOI: 10.3389/fmicb.2020.581219] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 12/14/2020] [Indexed: 01/15/2023] Open
Abstract
Termitomyces species are wild edible mushrooms that possess high nutritional value and a wide range of medicinal properties. However, the cultivation of these mushrooms is very difficult because of their symbiotic association with termites. In this study, we aimed to examine the differences in physicochemical indices and microbial communities between combs with Termitomyces basidiomes (CF) and combs without Termitomyces basidiomes (CNF). High-performance liquid chromatography (HPLC), inductively coupled plasma optical emission spectrometry (ICP-OES), gas chromatography equipped with a flame ionization detector (GC-FID), some commercial kits, high-throughput sequencing of the 16s RNA, and internal transcribed spacer (ITS) were used. Humidity, pH, and elements, i.e., Al, Ba, Fe, Mn, Ni, S, Ca, and Mg were higher while amino acids particularly alanine, tyrosine, and isoleucine were lower in CF as compared to CNF. The average contents of fatty acids were not significantly different between the two comb categories. The bacterial genera Alistipes, Burkholderia, Sediminibacterium, and Thermus were dominant in all combs. Brevibacterium, Brevundimonas, and Sediminibacterium were significantly more abundant in CF. Basidiomycota and Ascomycota were also identified in combs. Termitomyces clypeatus, Termitomyces sp. Group3, and Termitomyces sp. were the most dominant species in combs. However, any single Termitomyces species was abundantly present in an individual comb.
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Affiliation(s)
- Guiying Yang
- Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Farhan Ahmad
- Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China.,Entomology Section, Central Cotton Research Institute, Sakrand, Pakistan
| | - Qihuan Zhou
- Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Meixia Guo
- Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Shiyou Liang
- Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Hassan Ahmed Gaal
- Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China.,Department of Entomology, Faculty of Veterinary and Animal Husbandry, Somali National University, Mogadishu, Somalia
| | - Jianchu Mo
- Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
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Li H, Young SE, Poulsen M, Currie CR. Symbiont-Mediated Digestion of Plant Biomass in Fungus-Farming Insects. ANNUAL REVIEW OF ENTOMOLOGY 2021; 66:297-316. [PMID: 32926791 DOI: 10.1146/annurev-ento-040920-061140] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Feeding on living or dead plant material is widespread in insects. Seminal work on termites and aphids has provided profound insights into the critical nutritional role that microbes play in plant-feeding insects. Some ants, beetles, and termites, among others, have evolved the ability to use microbes to gain indirect access to plant substrate through the farming of a fungus on which they feed. Recent genomic studies, including studies of insect hosts and fungal and bacterial symbionts, as well as metagenomics and proteomics, have provided important insights into plant biomass digestion across insect-fungal mutualisms. Not only do advances in understanding of the divergent and complementary functions of complex symbionts reveal the mechanism of how these herbivorous insects catabolize plant biomass, but these symbionts also represent a promising reservoir for novel carbohydrate-active enzyme discovery, which is of considerable biotechnological interest.
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Affiliation(s)
- Hongjie Li
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Key Laboratory of Biotechnology in Plant Protection of Ministry of Agriculture and Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo 315211, China;
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA; ,
- Department of Energy Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, Wisconsin 53726, USA
| | - Soleil E Young
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA; ,
| | - Michael Poulsen
- Section for Ecology and Evolution, Department of Biology, University of Copenhagen, 2100 Copenhagen East, Denmark;
| | - Cameron R Currie
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA; ,
- Department of Energy Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, Wisconsin 53726, USA
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