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Zeng X, Gao H, Wang R, Majcher BM, Woon JS, Wenda C, Eggleton P, Griffiths HM, Ashton LA. Global contribution of invertebrates to forest litter decomposition. Ecol Lett 2024; 27:e14423. [PMID: 38584578 DOI: 10.1111/ele.14423] [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: 03/01/2023] [Revised: 02/15/2024] [Accepted: 03/12/2024] [Indexed: 04/09/2024]
Abstract
Forest litter decomposition is an essential component of global carbon and nutrient turnover. Invertebrates play important roles in litter decomposition, but the regional pattern of their effects is poorly understood. We examined 476 case studies across 93 sites and performed a meta-analysis to estimate regional effects of invertebrates on forest litter decomposition. We then assessed how invertebrate diversity, climate and soil pH drive regional variations in invertebrate-mediated decomposition. We found that (1) invertebrate contributions to litter decomposition are 1.4 times higher in tropical and subtropical forests than in forests elsewhere, with an overall contribution of 31% to global forest litter decomposition; and (2) termite diversity, together with warm, humid and acidic environments in the tropics and subtropics are positively associated with forest litter decomposition by invertebrates. Our results demonstrate the significant difference in invertebrate effects on mediating forest litter decomposition among regions. We demonstrate, also, the significance of termites in driving litter mass loss in the tropics and subtropics. These results are particularly pertinent in the tropics and subtropics where climate change and human disturbance threaten invertebrate biodiversity and the ecosystem services it provides.
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Affiliation(s)
- Xiaoyi Zeng
- School of Biological Sciences, University of Hong Kong, Hong Kong, China
| | - Huilin Gao
- Faculty of Business and Economics, University of Hong Kong, Hong Kong, China
| | - Runxi Wang
- School of Biological Sciences, University of Hong Kong, Hong Kong, China
| | - Bartosz M Majcher
- School of Biological Sciences, University of Hong Kong, Hong Kong, China
| | - Joel S Woon
- School of Environmental Sciences, University of Liverpool, Liverpool, UK
- Department of Life Sciences, Natural History Museum, London, UK
| | - Cheng Wenda
- School of Ecology, Sun Yat-Sen University, Guangdong, China
| | - Paul Eggleton
- Department of Life Sciences, Natural History Museum, London, UK
| | | | - Louise A Ashton
- School of Biological Sciences, University of Hong Kong, Hong Kong, China
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Schwarz M, Tokuda G, Osaki H, Mikaelyan A. Reevaluating Symbiotic Digestion in Cockroaches: Unveiling the Hindgut's Contribution to Digestion in Wood-Feeding Panesthiinae (Blaberidae). INSECTS 2023; 14:768. [PMID: 37754736 PMCID: PMC10531843 DOI: 10.3390/insects14090768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 09/08/2023] [Accepted: 09/12/2023] [Indexed: 09/28/2023]
Abstract
Cockroaches of the subfamily Panesthiinae (family Blaberidae) are among the few major groups of insects feeding on decayed wood. Despite having independently evolved the ability to thrive on this recalcitrant and nitrogen-limited resource, they are among the least studied of all wood-feeding insect groups. In the pursuit of unraveling their unique digestive strategies, we explored cellulase and xylanase activity in the crop, midgut, and hindgut lumens of Panesthia angustipennis and Salganea taiwanensis. Employing Percoll density gradient centrifugation, we further fractionated luminal fluid to elucidate how the activities in the gut lumen are further partitioned. Our findings challenge conventional wisdom, underscoring the significant contribution of the hindgut, which accounts for approximately one-fifth of cellulase and xylanase activity. Particle-associated enzymes, potentially of bacterial origin, dominate hindgut digestion, akin to symbiotic strategies observed in select termites and passalid beetles. Our study sheds new light on the digestive prowess of panesthiine cockroaches, providing invaluable insights into the evolution of wood-feeding insects and their remarkable adaptability to challenging, nutrient-poor substrates.
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Affiliation(s)
- Melbert Schwarz
- Department of Entomology and Plant Pathology, North Carolina State University, 100 Derieux Place, Raleigh, NC 27695, USA; (M.S.); (H.O.)
| | - Gaku Tokuda
- Center of Molecular Biosciences, Tropical Biosphere Research Center, University of the Ryukyus, Nishihara-cho, Okinawa 903-0213, Japan;
| | - Haruka Osaki
- Department of Entomology and Plant Pathology, North Carolina State University, 100 Derieux Place, Raleigh, NC 27695, USA; (M.S.); (H.O.)
- Department of Agriculture, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto 606-8502, Japan
| | - Aram Mikaelyan
- Department of Entomology and Plant Pathology, North Carolina State University, 100 Derieux Place, Raleigh, NC 27695, USA; (M.S.); (H.O.)
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Bhuvaragavan S, Reshma T, Hilda K, Meenakumari M, Sruthi K, Nivetha R, Janarthanan S. Predominant contribution of an endogenous cellulase (OlCel) to the cellulolysis in the digestive system of larvae of banana pseudostem weevil, Odoiporus longicollis (Coleoptera: Curculionidae). ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2023; 114:e22031. [PMID: 37322608 DOI: 10.1002/arch.22031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 06/03/2023] [Accepted: 06/06/2023] [Indexed: 06/17/2023]
Abstract
Insects have evolved with effective strategies to utilize cellulose as an energy source by possessing cellulolytic enzymes which can be used as an optimal resource in the bioenergy sector. The study was aimed at evaluating the cellulolytic enzyme in the larval gut of the banana pseudostem weevil, Odoiporus longicollis Olivier (Coleoptera: Curculionidae). Primarily, cellulase activity was localized along the gut, in which the midgut showed the highest activity (2858 U/mg). The thermo-tolerance of cellulase activity was found to be up to 80°C (highest at 60°C), and the enzyme was stable at a pH between 5 and 6. Various concentrations of divalent cations (CaCl2 , MgCl2 , and CuCl2 ) have differential enhancing and inhibitory effects on cellulase activity. The cellulase (OlCel) was purified using anion exchange chromatography. The molecular weight of the cellulase was determined to be 47 kDa. The physicochemical parameters of the purified enzyme were similar to that of enzyme activity of whole gut extract. Mass spectrometry results identified sequence similarities of purified cellulase to the glycosyl hydrolase family 5 (GHF5) family. The gut microbial cellulase activity as exogenous source showed no competence compared with the endogenous activity.
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Affiliation(s)
| | | | | | | | - Kannan Sruthi
- Department of Zoology, University of Madras, Chennai, India
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Veenstra JA. Evolution of a Cockroach Allergen into the Major Protein of Termite Royal Jelly. Int J Mol Sci 2023; 24:10311. [PMID: 37373456 DOI: 10.3390/ijms241210311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 05/23/2023] [Accepted: 06/16/2023] [Indexed: 06/29/2023] Open
Abstract
Termites live in colonies, and their members belong to different castes that each have their specific role within the termite society. In well-established colonies of higher termites, the only food the founding female, the queen, receives is saliva from workers; such queens can live for many years and produce up to 10,000 eggs per day. In higher termites, worker saliva must thus constitute a complete diet and therein resembles royal jelly produced by the hypopharyngeal glands of honeybee workers that serves as food for their queens; indeed, it might as well be called termite royal jelly. However, whereas the composition of honeybee royal jelly is well established, that of worker termite saliva in higher termites remains largely unknown. In lower termites, cellulose-digesting enzymes constitute the major proteins in worker saliva, but these enzymes are absent in higher termites. Others identified a partial protein sequence of the major saliva protein of a higher termite and identified it as a homolog of a cockroach allergen. Publicly available genome and transcriptome sequences from termites make it possible to study this protein in more detail. The gene coding the termite ortholog was duplicated, and the new paralog was preferentially expressed in the salivary gland. The amino acid sequence of the original allergen lacks the essential amino acids methionine, cysteine and tryptophan, but the salivary paralog incorporated these amino acids, thus allowing it to become more nutritionally balanced. The gene is found in both lower and higher termites, but it is in the latter that the salivary paralog gene got reamplified, facilitating an even higher expression of the allergen. This protein is not expressed in soldiers, and, like the major royal jelly proteins in honeybees, it is expressed in young but not old workers.
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Affiliation(s)
- Jan A Veenstra
- INCIA UMR 5287 CNRS, Université de Bordeaux, 33600 Pessac, France
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Liu J, You C, Xu Z, Liu Y, Zhang L, Li H, Wang L, Liu S, He S, Luo Z, Tan B. Soil arthropods promote litter enzyme activity by regulating microbial carbon limitation and ecoenzymatic stoichiometry in a subalpine forest. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 876:162789. [PMID: 36914138 DOI: 10.1016/j.scitotenv.2023.162789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Revised: 03/06/2023] [Accepted: 03/06/2023] [Indexed: 06/18/2023]
Abstract
Soil arthropods are crucial decomposers of litter at both global and local scales, yet their functional roles in mediating microbial activity during litter decomposition remain poorly understood. Here, we conducted a two-year field experiment using litterbags to assess the effects of soil arthropods on the extracellular enzyme activities (EEAs) in two litter substrates (Abies faxoniana and Betula albosinensis) in a subalpine forest. A biocide (naphthalene) was used to permit (nonnaphthalene) or exclude (naphthalene application) the presence of soil arthropods in litterbags during decomposition. Our results showed that biocide application was effective in reducing the abundance of soil arthropods in litterbags, with the density and species richness of soil arthropods decreasing by 64.18-75.45 % and 39.19-63.30 %, respectively. Litter with soil arthropods had a greater activity of C-degrading (β-glucosidase, cellobiohydrolase, polyphenol oxidase, peroxidase), N-degrading (N-acetyl-β-D-glucosaminidase, leucine arylamidase) and P-degrading (phosphatase) enzymes than litter from which soil arthropods were excluded. The contributions of soil arthropods to C-, N- and P-degrading EEAs in the fir litter were 38.09 %, 15.62 % and 61.69 %, and those for the birch litter were 27.97 %, 29.18 % and 30.40 %, respectively. Furthermore, the stoichiometric analyses of enzyme activity indicated that there was potential C and P colimitation in both the soil arthropod inclusion and exclusion litterbags, and the presence of soil arthropods decreased C limitation in the two litter species. Our structural equation models suggested that soil arthropods indirectly promoted C-, N- and P-degrading EEAs by regulating the litter C content and litter stoichiometry (e.g., N/P, LN/N and C/P) during litter decomposition. These results demonstrate that soil arthropods play an important functional role in modulating EEAs during litter decomposition.
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Affiliation(s)
- Jingru Liu
- Institute of Ecology & Forestry, Forestry Ecological Engineering in Upper Reaches of Yangtze River Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Forest Resources Conservation and Ecological Security in Upper Reaches of Yangtze River, Chengdu 611130, China
| | - Chengming You
- Institute of Ecology & Forestry, Forestry Ecological Engineering in Upper Reaches of Yangtze River Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Forest Resources Conservation and Ecological Security in Upper Reaches of Yangtze River, Chengdu 611130, China
| | - Zhenfeng Xu
- Institute of Ecology & Forestry, Forestry Ecological Engineering in Upper Reaches of Yangtze River Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Forest Resources Conservation and Ecological Security in Upper Reaches of Yangtze River, Chengdu 611130, China
| | - Yang Liu
- Institute of Ecology & Forestry, Forestry Ecological Engineering in Upper Reaches of Yangtze River Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Forest Resources Conservation and Ecological Security in Upper Reaches of Yangtze River, Chengdu 611130, China
| | - Li Zhang
- Institute of Ecology & Forestry, Forestry Ecological Engineering in Upper Reaches of Yangtze River Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Forest Resources Conservation and Ecological Security in Upper Reaches of Yangtze River, Chengdu 611130, China
| | - Han Li
- Institute of Ecology & Forestry, Forestry Ecological Engineering in Upper Reaches of Yangtze River Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Forest Resources Conservation and Ecological Security in Upper Reaches of Yangtze River, Chengdu 611130, China
| | - Lixia Wang
- Institute of Ecology & Forestry, Forestry Ecological Engineering in Upper Reaches of Yangtze River Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Forest Resources Conservation and Ecological Security in Upper Reaches of Yangtze River, Chengdu 611130, China
| | - Sining Liu
- Institute of Ecology & Forestry, Forestry Ecological Engineering in Upper Reaches of Yangtze River Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Forest Resources Conservation and Ecological Security in Upper Reaches of Yangtze River, Chengdu 611130, China
| | - Shuqin He
- Institute of Ecology & Forestry, Forestry Ecological Engineering in Upper Reaches of Yangtze River Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Forest Resources Conservation and Ecological Security in Upper Reaches of Yangtze River, Chengdu 611130, China
| | - Ziteng Luo
- Institute of Ecology & Forestry, Forestry Ecological Engineering in Upper Reaches of Yangtze River Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Forest Resources Conservation and Ecological Security in Upper Reaches of Yangtze River, Chengdu 611130, China
| | - Bo Tan
- Institute of Ecology & Forestry, Forestry Ecological Engineering in Upper Reaches of Yangtze River Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Forest Resources Conservation and Ecological Security in Upper Reaches of Yangtze River, Chengdu 611130, China.
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Adedara IA, Mohammed KA, Da-Silva OF, Salaudeen FA, Gonçalves FL, Rosemberg DB, Aschner M, Rocha JBT, Farombi EO. Utility of cockroach as a model organism in the assessment of toxicological impacts of environmental pollutants. ENVIRONMENTAL ADVANCES 2022; 8:100195. [PMID: 35992224 PMCID: PMC9390120 DOI: 10.1016/j.envadv.2022.100195] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Environmental pollution is a global concern because of its associated risks to human health and ecosystem. The bio-monitoring of environmental health has attracted much attention in recent years and efforts to minimize environmental contamination as well as to delineate toxicological mechanisms related to toxic exposure are essential to improve the health conditions of both humans and animals. This review aims to substantiate the need and advantages in utilizing cockroaches as a complementary, non-mammalian model to further understand the noxious impact of environmental contaminants on humans and animals. We discuss recent advances in neurotoxicology, immunotoxicology, reproductive and developmental toxicology, environmental forensic entomotoxicology, and environmental toxicology that corroborate the utility of the cockroach (Periplaneta americana, Blaptica dubia, Blattella germanica and Nauphoeta cinerea) in addressing toxicological mechanisms as well as a sensor of environmental pollution. Indeed, recent improvements in behavioural assessment and the detection of potential biomarkers allow for the recognition of phenotypic alterations in cockroaches following exposure to toxic chemicals namely saxitoxin, methylmercury, polychlorinated biphenyls, electromagnetic fields, pharmaceuticals, polycyclic aromatic hydrocarbon, chemical warfare agents and nanoparticles. The review provides a state-of-the-art update on the current utility of cockroach models in various aspects of toxicology as well as discusses the potential limitations and future perspectives.
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Affiliation(s)
- Isaac A. Adedara
- Drug Metabolism and Toxicology Research Laboratories, Department of Biochemistry, College of Medicine, University of Ibadan, Ibadan, Nigeria
- Departamento de Bioquímica e Biologia Molecular, CCNE, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil
- Corresponding author. (I.A. Adedara)
| | - Khadija A. Mohammed
- Drug Metabolism and Toxicology Research Laboratories, Department of Biochemistry, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Oluwatobiloba F. Da-Silva
- Drug Metabolism and Toxicology Research Laboratories, Department of Biochemistry, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Faoziyat A. Salaudeen
- Drug Metabolism and Toxicology Research Laboratories, Department of Biochemistry, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Falco L.S. Gonçalves
- Departamento de Bioquímica e Biologia Molecular, CCNE, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil
| | - Denis B. Rosemberg
- Departamento de Bioquímica e Biologia Molecular, CCNE, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil
| | - Michael Aschner
- Department of Molecular Pharmacology; Albert Einstein College of Medicine Forchheimer 209; 1300 Morris Park Avenue, Bronx, NY 10461, U.S.A
| | - Joao B. T. Rocha
- Departamento de Bioquímica e Biologia Molecular, CCNE, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil
| | - Ebenezer O. Farombi
- Drug Metabolism and Toxicology Research Laboratories, Department of Biochemistry, College of Medicine, University of Ibadan, Ibadan, Nigeria
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Genomic and transcriptomic analyses of the subterranean termite Reticulitermes speratus: Gene duplication facilitates social evolution. Proc Natl Acad Sci U S A 2022; 119:2110361119. [PMID: 35042774 PMCID: PMC8785959 DOI: 10.1073/pnas.2110361119] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/01/2021] [Indexed: 12/26/2022] Open
Abstract
Gene duplication is a major source of evolutionary innovation and is associated with the increases in biological complexity and adaptive radiation. Termites are model social organisms characterized by a sophisticated caste system. We analyzed the genome of the Japanese subterranean termite, an ecologically and economically important insect acting as a destructive pest. The analyses revealed the significance of gene duplication in social evolution. Gene duplication associated with caste-biased gene expression was prevalent in the termite genome. Many of the duplicated genes were related to social functions, such as chemical communication, social immunity, and defense, and they were often expressed in caste-specific organs. We propose that gene duplication facilitates social evolution through regulatory diversification leading to caste-biased expression and functional specialization. Termites are model social organisms characterized by a polyphenic caste system. Subterranean termites (Rhinotermitidae) are ecologically and economically important species, including acting as destructive pests. Rhinotermitidae occupies an important evolutionary position within the clade representing a transitional taxon between the higher (Termitidae) and lower (other families) termites. Here, we report the genome, transcriptome, and methylome of the Japanese subterranean termite Reticulitermes speratus. Our analyses highlight the significance of gene duplication in social evolution in this termite. Gene duplication associated with caste-biased gene expression was prevalent in the R. speratus genome. The duplicated genes comprised diverse categories related to social functions, including lipocalins (chemical communication), cellulases (wood digestion and social interaction), lysozymes (social immunity), geranylgeranyl diphosphate synthase (social defense), and a novel class of termite lineage–specific genes with unknown functions. Paralogous genes were often observed in tandem in the genome, but their expression patterns were highly variable, exhibiting caste biases. Some of the assayed duplicated genes were expressed in caste-specific organs, such as the accessory glands of the queen ovary and the frontal glands of soldier heads. We propose that gene duplication facilitates social evolution through regulatory diversification, leading to caste-biased expression and subfunctionalization and/or neofunctionalization conferring caste-specialized functions.
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9
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Griffiths HM, Ashton LA, Parr CL, Eggleton P. The impact of invertebrate decomposers on plants and soil. THE NEW PHYTOLOGIST 2021; 231:2142-2149. [PMID: 34128548 DOI: 10.1111/nph.17553] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 05/21/2021] [Indexed: 06/12/2023]
Abstract
Soil invertebrates make significant contributions to the recycling of dead plant material across the globe. However, studies focussed on the consequences of decomposition for plant communities largely ignore soil fauna across all ecosystems, because microbes are often considered the primary agents of decay. Here, we explore the role of invertebrates as not simply facilitators of microbial decomposition, but as true decomposers, able to break down dead organic matter with their own endogenic enzymes, with direct and indirect impacts on the soil environment and plants. We recommend a holistic view of decomposition, highlighting how invertebrates and microbes act in synergy to degrade organic matter, providing ecological services that underpin plant growth and survival.
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Affiliation(s)
- Hannah M Griffiths
- School of Biological Sciences, University of Bristol, Bristol, BS8 1TQ, UK
| | - Louise A Ashton
- Division of Ecology & Biodiversity, School of Biological Sciences, The University of Hong Kong, Hong Kong, China
| | - Catherine L Parr
- School of Environmental Sciences, University of Liverpool, Liverpool, L69 3GP, UK
- Department of Zoology & Entomology, University of Pretoria, Pretoria, 0028, South Africa
- School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Johannesburg, 2050, South Africa
| | - Paul Eggleton
- Department of Life Sciences, Natural History Museum, London, SW7 5BD, UK
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Glasgow E, Vander Meulen K, Kuch N, Fox BG. Multifunctional cellulases are potent, versatile tools for a renewable bioeconomy. Curr Opin Biotechnol 2021; 67:141-148. [PMID: 33550093 PMCID: PMC8366578 DOI: 10.1016/j.copbio.2020.12.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 12/09/2020] [Accepted: 12/28/2020] [Indexed: 11/21/2022]
Abstract
Enzyme performance is critical to the future bioeconomy based on renewable plant materials. Plant biomass can be efficiently hydrolyzed by multifunctional cellulases (MFCs) into sugars suitable for conversion into fuels and chemicals, and MFCs fall into three functional categories. Recent work revealed MFCs with broad substrate specificity, dual exo-activity/endo-activity on cellulose, and intramolecular synergy, among other novel characteristics. Binding modules and accessory catalytic domains amplify MFC and xylanase activity in a wide variety of ways, and processive endoglucanases achieve autosynergy on cellulose. Multidomain MFCs from Caldicellulosiruptor are heat-tolerant, adaptable to variable cellulose crystallinity, and may provide interchangeable scaffolds for recombinant design. Further studies of MFC properties and their reactivity with plant biomass are recommended for increasing biorefinery yields.
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Affiliation(s)
- Evan Glasgow
- Dept. of Biochemistry, University of Wisconsin - Madison, 433 Babcock Dr., Madison, WI, 53706, United States; Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, 1552 University Ave, Madison, WI, 53726, United States
| | - Kirk Vander Meulen
- Dept. of Biochemistry, University of Wisconsin - Madison, 433 Babcock Dr., Madison, WI, 53706, United States; Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, 1552 University Ave, Madison, WI, 53726, United States
| | - Nate Kuch
- Dept. of Biochemistry, University of Wisconsin - Madison, 433 Babcock Dr., Madison, WI, 53706, United States; Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, 1552 University Ave, Madison, WI, 53726, United States
| | - Brian G Fox
- Dept. of Biochemistry, University of Wisconsin - Madison, 433 Babcock Dr., Madison, WI, 53706, United States; Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, 1552 University Ave, Madison, WI, 53726, United States.
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Integrative omics analysis of the termite gut system adaptation to Miscanthus diet identifies lignocellulose degradation enzymes. Commun Biol 2020; 3:275. [PMID: 32483294 PMCID: PMC7264248 DOI: 10.1038/s42003-020-1004-3] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 05/13/2020] [Indexed: 01/05/2023] Open
Abstract
Miscanthus sp. biomass could satisfy future biorefinery value chains. However, its use is largely untapped due to high recalcitrance. The termite and its gut microbiome are considered the most efficient lignocellulose degrading system in nature. Here, we investigate at holobiont level the dynamic adaptation of Cortaritermes sp. to imposed Miscanthus diet, with a long-term objective of overcoming lignocellulose recalcitrance. We use an integrative omics approach combined with enzymatic characterisation of carbohydrate active enzymes from termite gut Fibrobacteres and Spirochaetae. Modified gene expression profiles of gut bacteria suggest a shift towards utilisation of cellulose and arabinoxylan, two main components of Miscanthus lignocellulose. Low identity of reconstructed microbial genomes to closely related species supports the hypothesis of a strong phylogenetic relationship between host and its gut microbiome. This study provides a framework for better understanding the complex lignocellulose degradation by the higher termite gut system and paves a road towards its future bioprospecting. Through metagenomics and metatranscriptomics analyses, Calusinska et al. investigate the adaptation of the gut microbiome of the termite Cortaritermes sp. to a diet of Miscanthus grass. This work is a starting point for the identification of lignocellulose-degradation enzymes for potential biotechnology applications.
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Shelomi M, Lin SS, Liu LY. Transcriptome and microbiome of coconut rhinoceros beetle (Oryctes rhinoceros) larvae. BMC Genomics 2019; 20:957. [PMID: 31818246 PMCID: PMC6902462 DOI: 10.1186/s12864-019-6352-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Accepted: 11/29/2019] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND The coconut rhinoceros beetle, Oryctes rhinoceros, is a major pest of palm crops in tropical Asia and the Pacific Islands. Little molecular data exists for this pest, impeding our ability to develop effective countermeasures and deal with the species' growing resistance to viral biocontrols. We present the first molecular biology analyses of this species, including a metagenomic assay to understand the microbiome of different sections of its digestive tract, and a transcriptomics assay to complement the microbiome data and to shed light on genes of interest like plant cell wall degrading enzymes and immunity and xenobiotic resistance genes. RESULTS The gut microbiota of Oryctes rhinoceros larvae is quite similar to that of the termite gut, as both species feed on decaying wood. We found the first evidence for endogenous beta-1,4-endoglucanase in the beetle, plus evidence for microbial cellobiase, suggesting the beetle can degrade cellulose together with its gut microfauna. A number of antimicrobial peptides are expressed, particularly by the fat body but also by the midgut and hindgut. CONCLUSIONS This transcriptome provides a wealth of data about the species' defense against chemical and biological threats, has uncovered several potentially new species of microbial symbionts, and significantly expands our knowledge about this pest.
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Affiliation(s)
- Matan Shelomi
- Department of Entomology, National Taiwan University, No 27 Lane 113 Sec 4 Roosevelt Rd, Taipei, 10617 Taiwan
| | - Shih-Shun Lin
- Institute of Biotechnology, National Taiwan University, Taipei, Taiwan
| | - Li-Yu Liu
- Department of Agronomy, National Taiwan University, Taipei, Taiwan
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