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Qi G, Hao L, Xin T, Gan Y, Lou Q, Xu W, Song J. Analysis of Whole-Genome facilitates rapid and precise identification of fungal species. Front Microbiol 2024; 15:1336143. [PMID: 38500585 PMCID: PMC10946254 DOI: 10.3389/fmicb.2024.1336143] [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: 11/10/2023] [Accepted: 02/13/2024] [Indexed: 03/20/2024] Open
Abstract
Fungal identification is a cornerstone of fungal research, yet traditional molecular methods struggle with rapid and accurate onsite identification, especially for closely related species. To tackle this challenge, we introduce a universal identification method called Analysis of whole GEnome (AGE). AGE includes two key steps: bioinformatics analysis and experimental practice. Bioinformatics analysis screens candidate target sequences named Targets within the genome of the fungal species and determines specific Targets by comparing them with the genomes of other species. Then, experimental practice using sequencing or non-sequencing technologies would confirm the results of bioinformatics analysis. Accordingly, AGE obtained more than 1,000,000 qualified Targets for each of the 13 fungal species within the phyla Ascomycota and Basidiomycota. Next, the sequencing and genome editing system validated the ultra-specific performance of the specific Targets; especially noteworthy is the first-time demonstration of the identification potential of sequences from unannotated genomic regions. Furthermore, by combining rapid isothermal amplification and phosphorothioate-modified primers with the option of an instrument-free visual fluorescence method, AGE can achieve qualitative species identification within 30 min using a single-tube test. More importantly, AGE holds significant potential for identifying closely related species and differentiating traditional Chinese medicines from their adulterants, especially in the precise detection of contaminants. In summary, AGE opens the door for the development of whole-genome-based fungal species identification while also providing guidance for its application in plant and animal kingdoms.
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Affiliation(s)
- Guihong Qi
- Key Lab of Chinese Medicine Resources Conservation, State Administration of Traditional Chinese Medicine of the People’s Republic of China, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Lijun Hao
- Key Lab of Chinese Medicine Resources Conservation, State Administration of Traditional Chinese Medicine of the People’s Republic of China, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Tianyi Xin
- Key Lab of Chinese Medicine Resources Conservation, State Administration of Traditional Chinese Medicine of the People’s Republic of China, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Yutong Gan
- Key Lab of Chinese Medicine Resources Conservation, State Administration of Traditional Chinese Medicine of the People’s Republic of China, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Qian Lou
- Key Lab of Chinese Medicine Resources Conservation, State Administration of Traditional Chinese Medicine of the People’s Republic of China, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Wenjie Xu
- Key Lab of Chinese Medicine Resources Conservation, State Administration of Traditional Chinese Medicine of the People’s Republic of China, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Jingyuan Song
- Key Lab of Chinese Medicine Resources Conservation, State Administration of Traditional Chinese Medicine of the People’s Republic of China, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
- Engineering Research Center of Chinese Medicine Resource, Ministry of Education, Beijing, China
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2
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Kim JC, Hwang IM, Kim HM, Kim S, Shin TS, Woo SD, Park HW. Rapid analysis of insecticidal metabolites from the entomopathogenic fungus Beauveria bassiana 331R using UPLC-Q-Orbitrap MS. Mycotoxin Res 2024; 40:123-132. [PMID: 37968430 DOI: 10.1007/s12550-023-00509-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 10/18/2023] [Accepted: 11/06/2023] [Indexed: 11/17/2023]
Abstract
Beauveria bassiana, a representative entomopathogenic fungus, is increasingly being utilized as an eco-friendly pest management alternative to chemical insecticides. This fungus produces a range of insecticidal secondary metabolites that act as antimicrobial and immunosuppressive agents. However, detailed qualitative and quantitative analysis related to these compounds remains scarce, we developed a method for the rapid analysis of these metabolites. Eight secondary metabolites (bassianin, bassianolide, beauvericin, beauveriolide I, enniatin A, A1, and B, and tenellin) were efficiently extracted when B. bassiana-infected Tenebrio molitor larvae were ground in 70% EtOH extraction solvent and subsequently subjected to ultrasonic treatment for 30 min. The eight metabolites were rapidly and simultaneously analyzed using ultra-performance liquid chromatography-quadrupole-Orbitrap mass spectrometry (UPLC-Q-Orbitrap MS). Bassianolide (20.6-51.1 µg/g) and beauvericin (63.6-109.8 µg/g) were identified as the main metabolites in B. basssiana-infected larvae, indicating that they are likely major toxins of B. bassiana. Validation of the method exhibited recovery rates in the range of 80-115% and precision in the range of 0.1-8.0%, indicating no significant interference from compounds in the matrix. We developed a method to rapidly analyze eight insecticidal metabolites using UPLC-Q-Orbitrap MS. This can be extensively utilized for detecting and producing insecticidal fungal secondary metabolites.
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Affiliation(s)
- Jong-Cheol Kim
- Technology Innovation Research Division, World Institute of Kimchi, Gwangju, 61755, Republic of Korea
| | - In Min Hwang
- Technology Innovation Research Division, World Institute of Kimchi, Gwangju, 61755, Republic of Korea
| | - Ho Myeong Kim
- Technology Innovation Research Division, World Institute of Kimchi, Gwangju, 61755, Republic of Korea
| | - Seulbi Kim
- Technology Innovation Research Division, World Institute of Kimchi, Gwangju, 61755, Republic of Korea
- Division of Applied Bioscience & Biotechnology, Chonnam National University, Gwangju, 500-757, Republic of Korea
| | - Teak Su Shin
- R&D Center, Solvm Co., Ltd., Daejeon, 34014, Republic of Korea
| | - Soo-Dong Woo
- Department of Agricultural Biology, College of Agriculture, Life & Environment Science, Chungbuk National University, Cheongju, 28644, Republic of Korea
| | - Hae Woong Park
- Technology Innovation Research Division, World Institute of Kimchi, Gwangju, 61755, Republic of Korea.
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3
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Wang Y, Liu Z, Yin X, Liu S, Wang K, Wan R, Chen H, Li X, Huang B. Variation in Bombyx mori immune response against fungal pathogen Beauveria bassiana with variability in cell wall β-1,3-glucan. INSECT SCIENCE 2024; 31:211-224. [PMID: 37350124 DOI: 10.1111/1744-7917.13209] [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: 01/04/2023] [Revised: 04/03/2023] [Accepted: 04/04/2023] [Indexed: 06/24/2023]
Abstract
Entomopathogenic fungi are protected by a cell wall with dynamic structure for adapting to various environmental conditions. β-1,3-Glucan recognition proteins activate the innate immune system of insects by recognizing surface molecules of fungi. However, the associations between pathogenicity and the different components of entomopathogenic fungal cell walls remain unclear. Three Beauveria bassiana strains were selected that have significantly differing virulence against Bombyx mori. The molecular mechanisms underlying the immune response in B. mori were investigated using RNA sequencing, which revealed differences in the immune response to different B. bassiana strains at 12 h post-infection. Immunofluorescence assays revealed that β-1,3-glucan content had an opposite trend to that of fungal virulence. β-1,3-Glucan injection upregulated BmβGRP4 expression and significantly reduced the virulence of the high-virulence strain but not that of the medium-virulence or low-virulence strains. BmβGRP4 silencing in B. mori with RNA interference resulted in the opposite virulence pattern, indicating that the virulence of B. bassiana was affected by the cell walls' content of β-1,3-glucan, which could be recognized by BmβGRP4. Furthermore, interference with the gene CnA (calcineurin catalytic A subunit) involved in β-1,3-glucan synthesis eliminated differences in virulence between B. bassiana strains. These results indicate that strains of a single species of pathogenic fungi that have differing cell wall components are recognized differently by the innate immune system of B. mori.
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Affiliation(s)
- Yulong Wang
- Anhui Provincial Key Laboratory of Microbial Pest Control, Anhui Agricultural University, Hefei, China
| | - Zhen Liu
- Anhui Provincial Key Laboratory of Microbial Pest Control, Anhui Agricultural University, Hefei, China
| | - Xuebing Yin
- Anhui Provincial Key Laboratory of Microbial Pest Control, Anhui Agricultural University, Hefei, China
| | - Shihong Liu
- Anhui Provincial Key Laboratory of Microbial Pest Control, Anhui Agricultural University, Hefei, China
| | - Kai Wang
- Anhui Provincial Key Laboratory of Microbial Pest Control, Anhui Agricultural University, Hefei, China
| | - Rongjie Wan
- Anhui Provincial Key Laboratory of Microbial Pest Control, Anhui Agricultural University, Hefei, China
| | - Haoran Chen
- Anhui Provincial Key Laboratory of Microbial Pest Control, Anhui Agricultural University, Hefei, China
| | - Xinyang Li
- Anhui Provincial Key Laboratory of Microbial Pest Control, Anhui Agricultural University, Hefei, China
| | - Bo Huang
- Anhui Provincial Key Laboratory of Microbial Pest Control, Anhui Agricultural University, Hefei, China
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4
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Quesada-Moraga E, Garrido-Jurado I, González-Mas N, Yousef-Yousef M. Ecosystem services of entomopathogenic ascomycetes. J Invertebr Pathol 2023; 201:108015. [PMID: 37924859 DOI: 10.1016/j.jip.2023.108015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 10/27/2023] [Accepted: 10/31/2023] [Indexed: 11/06/2023]
Abstract
Entomopathogenic ascomycetes (EA) are an important part of the microbiota in most terrestrial ecosystems, where they can be found regulating natural populations of arthropod pests in both epigeous and hypogeous habitats while also establishing unique relationships with plants. These fungi offer direct benefits to agriculture and human welfare. In the present work, we conducted a systematic review to comprehensively assess the range of ecosystem services provided by EA, including direct and indirect pest biocontrol, plant growth promotion, plant defense against other biotic and abiotic stresses, nutrient cycling, and the production of new bioactive compounds with agricultural, pharmaceutical and medical importance. Moreover, EA are compatible with the ecosystem services provided by other microbial and macrobial biocontrol agents. This systematic review identified the need for future research to focus on evaluating the economic value of the ecological services provided by EA with a special emphasis on hypocrealean fungi. This evaluation is essential not only for the conservation but also for better regulation and exploitation of the benefits of EA in promoting agricultural sustainability, reducing the use of chemicals that enter the environment, and minimizing the negative impacts of crop protection on the carbon footprint and human health.
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Affiliation(s)
- Enrique Quesada-Moraga
- Department of Agronomy, Maria de Maeztu Excellence Unit DAUCO, ETSIAM, University of Cordoba, Edificio C4 Celestino Mutis, Campus de Rabanales, 14071 Cordoba, Spain.
| | - Inmaculada Garrido-Jurado
- Department of Agronomy, Maria de Maeztu Excellence Unit DAUCO, ETSIAM, University of Cordoba, Edificio C4 Celestino Mutis, Campus de Rabanales, 14071 Cordoba, Spain
| | - Natalia González-Mas
- Department of Agronomy, Maria de Maeztu Excellence Unit DAUCO, ETSIAM, University of Cordoba, Edificio C4 Celestino Mutis, Campus de Rabanales, 14071 Cordoba, Spain
| | - Meelad Yousef-Yousef
- Department of Agronomy, Maria de Maeztu Excellence Unit DAUCO, ETSIAM, University of Cordoba, Edificio C4 Celestino Mutis, Campus de Rabanales, 14071 Cordoba, Spain
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5
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Tu C, Zhang Y, Zhu P, Sun L, Xu P, Wang T, Luo J, Yu J, Xu L. Enhanced toxicity of entomopathogenic fungi Beauveria bassiana with bacteria expressing immune suppressive dsRNA in a leaf beetle. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2023; 193:105431. [PMID: 37248009 DOI: 10.1016/j.pestbp.2023.105431] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 04/11/2023] [Accepted: 04/18/2023] [Indexed: 05/31/2023]
Abstract
The entomopathogenic fungus is recognized as an ideal alternative to chemical pesticides, nonetheless, its efficacy is often limited by insect's innate immune system. The suppression of the host immunity may overcome the obstacle and promote the toxicity of the fungi. Here, by using an entomopathogenic fungus Beauveria bassiana and immune genes dsRNA-expressing bacteria, we explored the potentially synergistic toxicity of the two agents on a leaf beetle Plagiodera versicolora (Coleoptera: Chrysomelidae). We first determined the susceptibilities of P. versicolora to a B. bassiana 476 strain (hereafter referred to Bb476). And the immune genes were identified based on the transcriptome of Bb476 challenged beetles. Subsequently, five immune genes (PGRP1, Toll1, Domeless,SPN1,and Lysozyme) were targeted by feeding dsRNA-expressing bacteria, which produced a 71.4, 39.0, 72.0, 49.0, and 68.7% gene silencing effect, respectively. Furthermore, we found a significantly increased mortality of P. versicolora when combined the Bb476 and the immune suppressive dsRNAs. Taking together, this study highlights the importance of insect immunity in the defense of entomopathogens and also paves the way toward the development of a more efficient pest management strategy that integrates both entomopathogens and immune suppressive dsRNAs.
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Affiliation(s)
- Chengjie Tu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan 430062, China
| | - Yuxin Zhang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan 430062, China
| | - Peipei Zhu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan 430062, China
| | - Liuwei Sun
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan 430062, China
| | - Pei Xu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan 430062, China
| | - Tianjing Wang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan 430062, China
| | - Jing Luo
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan 430062, China
| | - Jingya Yu
- Institute of Plant Protection, Wuhan Institute of Landscape Architecture, Wuhan, China.
| | - Letian Xu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan 430062, China.
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6
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Vidhate RP, Dawkar VV, Punekar SA, Giri AP. Genomic Determinants of Entomopathogenic Fungi and Their Involvement in Pathogenesis. MICROBIAL ECOLOGY 2023; 85:49-60. [PMID: 34977966 DOI: 10.1007/s00248-021-01936-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 11/24/2021] [Indexed: 06/14/2023]
Abstract
Entomopathogenic fungi offer an effective and eco-friendly alternative to curb insect populations in biocontrol strategy. The evolutionary history of selected entomopathogenic fungi indicates their ancestral relationship with plant endophytes. During this host shifting, entomopathogenic fungi must have acquired multiple mechanisms, including a combination of various biomolecules that make them distinguishable from other fungi. In this review, we focus on understanding various biochemical and molecular mechanisms involved in entomopathogenesis. In particular, we attempt to explain the indispensable role of enlarged gene families of various virulent factors, viz. chitinases, proteases, lipases, specialized metabolites, and cytochrome P450, in entomopathogenesis. Our analysis suggests that entomopathogenic fungi recruit a different set of gene products during the progression of pathogenesis. Knowledge of these bio-molecular interactions between fungi and insect hosts will allow researchers to execute pointed efforts towards the development of improved entomopathogenic fungal strains.
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Affiliation(s)
- Ravindra P Vidhate
- Plant Molecular Biology Unit, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune, 411008, Maharashtra, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, Uttar Pradesh, India
| | - Vishal V Dawkar
- Plant Molecular Biology Unit, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune, 411008, Maharashtra, India
| | - Sachin A Punekar
- Biospheres, Eshwari, 52/403, Lakshminagar, Parvati, Pune, 411009, Maharashtra, India
| | - Ashok P Giri
- Plant Molecular Biology Unit, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune, 411008, Maharashtra, India.
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, Uttar Pradesh, India.
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7
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Li X, Chen HP, Zhou L, Fan J, Awakawa T, Mori T, Ushimaru R, Abe I, Liu JK. Cordycicadins A–D, Antifeedant Polyketides from the Entomopathogenic Fungus Cordyceps cicadae JXCH1. Org Lett 2022; 24:8627-8632. [DOI: 10.1021/acs.orglett.2c03432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- Xinyang Li
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - He-Ping Chen
- School of Pharmaceutical Sciences, South-Central Minzu University, Wuhan 430074, China
| | - Lin Zhou
- School of Pharmaceutical Sciences, South-Central Minzu University, Wuhan 430074, China
| | - Jing Fan
- School of Pharmaceutical Sciences, South-Central Minzu University, Wuhan 430074, China
| | - Takayoshi Awakawa
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
- Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
- RIKEN Center for Sustainable Resource Science, Wako, Saitama 351-0198, Japan
| | - Takahiro Mori
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
- Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Richiro Ushimaru
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
- Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Ikuro Abe
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
- Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Ji-Kai Liu
- School of Pharmaceutical Sciences, South-Central Minzu University, Wuhan 430074, China
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8
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Host and Environmental Sensing by Entomopathogenic Fungi to Infect Hosts. CURRENT CLINICAL MICROBIOLOGY REPORTS 2022. [DOI: 10.1007/s40588-022-00185-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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9
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Sheng H, McNamara PJ, St Leger RJ. Metarhizium: an opportunistic middleman for multitrophic lifestyles. Curr Opin Microbiol 2022; 69:102176. [PMID: 35872503 DOI: 10.1016/j.mib.2022.102176] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Revised: 06/10/2022] [Accepted: 06/23/2022] [Indexed: 02/05/2023]
Abstract
Metarhizium spp. mediate multiple interactions that are usually positive with respect to their long-term plant environment, and negative with respect to short-lived hosts. In particular, their ability to kill a wide range of insects maximizes protection to the plants and provides a resource of nitrogen that the fungus trades with the plant for carbon. Here, we highlight emerging concepts underlying Metarhizium-plant-insect interactions. Experiments on model systems have provided detailed mechanistic knowledge of how these fungi interact with plants and insects, and a greater understanding of the evolutionary forces driving these interactions. However, further integration of studies at the ecological and mechanistic level is needed to evaluate the importance of Metarhizium's multitrophic interactions to the structuring of natural communities.
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Affiliation(s)
- Huiyu Sheng
- Department of Entomology, University of Maryland, College Park, MD, United States
| | - Patrick J McNamara
- Department of Entomology, University of Maryland, College Park, MD, United States
| | - Raymond J St Leger
- Department of Entomology, University of Maryland, College Park, MD, United States.
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10
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Toopaang W, Bunnak W, Srisuksam C, Wattananukit W, Tanticharoen M, Yang YL, Amnuaykanjanasin A. Microbial polyketides and their roles in insect virulence: from genomics to biological functions. Nat Prod Rep 2022; 39:2008-2029. [PMID: 35822627 DOI: 10.1039/d1np00058f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Covering: May 1966 up to January 2022Entomopathogenic microorganisms have potential for biological control of insect pests. Their main secondary metabolites include polyketides, nonribosomal peptides, and polyketide-nonribosomal peptide (PK-NRP) hybrids. Among these secondary metabolites, polyketides have mainly been studied for structural identification, pathway engineering, and for their contributions to medicine. However, little is known about the function of polyketides in insect virulence. This review focuses on the role of bacterial and fungal polyketides, as well as PK-NRP hybrids in insect infection and killing. We also discuss gene distribution and evolutional relationships among different microbial species. Further, the role of microbial polyketides and the hybrids in modulating insect-microbial symbiosis is also explored. Understanding the mechanisms of polyketides in insect pathogenesis, how compounds moderate the host-fungus interaction, and the distribution of PKS genes across different fungi and bacteria will facilitate the discovery and development of novel polyketide-derived bio-insecticides.
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Affiliation(s)
- Wachiraporn Toopaang
- National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, 113 Thailand Science Park, Phahonyothin Rd., Khlong Nueng, Amphoe Khlong Luang, Pathum Thani 12120, Thailand. .,Molecular and Biological Agricultural Sciences, Taiwan International Graduate Program, Academia Sinica and National Chung Hsing University, Taiwan.,Agricultural Biotechnology Research Center, Academia Sinica, Taipei 11529, Taiwan.
| | - Warapon Bunnak
- National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, 113 Thailand Science Park, Phahonyothin Rd., Khlong Nueng, Amphoe Khlong Luang, Pathum Thani 12120, Thailand.
| | - Chettida Srisuksam
- National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, 113 Thailand Science Park, Phahonyothin Rd., Khlong Nueng, Amphoe Khlong Luang, Pathum Thani 12120, Thailand.
| | - Wilawan Wattananukit
- National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, 113 Thailand Science Park, Phahonyothin Rd., Khlong Nueng, Amphoe Khlong Luang, Pathum Thani 12120, Thailand.
| | - Morakot Tanticharoen
- School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, Bangkok 10140, Thailand
| | - Yu-Liang Yang
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei 11529, Taiwan. .,Biotechnology Center in Southern Taiwan, Academia Sinica, Tainan 711010, Taiwan
| | - Alongkorn Amnuaykanjanasin
- National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, 113 Thailand Science Park, Phahonyothin Rd., Khlong Nueng, Amphoe Khlong Luang, Pathum Thani 12120, Thailand.
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11
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Idrees A, Afzal A, Qadir ZA, Li J. Bioassays of Beauveria bassiana Isolates against the Fall Armyworm, Spodoptera frugiperda. J Fungi (Basel) 2022; 8:jof8070717. [PMID: 35887472 PMCID: PMC9324617 DOI: 10.3390/jof8070717] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 07/04/2022] [Accepted: 07/06/2022] [Indexed: 12/04/2022] Open
Abstract
The control of Spodoptera frugiperda, the key invasive pest of maize, is a serious concern due to its biology and the current global restriction on applying synthetic pesticides. Entomopathogenic fungi are considered to be a potential biological control strategy. The pathogenicity of 12 isolates of Beauveria bassiana in the immature stages and feeding efficacy of S. frugiperda were evaluated. The B. bassiana isolates QB-3.45, QB-3.46 and QB-3.428 caused the highest egg mortality rates of 87.3, 82.7 and 79.3%, respectively, when applied at a concentration of 1 × 108 conidia/mL and measured at 7 days post-treatment. Neonate mortality rates of 45.6 to 53.6% were observed with the same isolates. The B. bassiana isolates caused significant cumulative mortality rates ranging from 71.3 to 93.3% at 14 days post-treatment and reduced larval feeding efficacy from 69.4 to 77.8% at 48 h post-treatment. This study supports using the effective B. bassiana isolates as a biological control agent against S. frugiperda. The significant mortality of the eggs and neonatal larvae and the reduction in the feeding efficacy of the second instar larvae of the S. frugiperda that were treated with isolates of B. bassiana supports the application of entomopathogenic fungi as a biocontrol agent for the effective control of the S. frugiperda population.
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Affiliation(s)
- Atif Idrees
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou 510260, China; (A.I.); (A.A.)
| | - Ayesha Afzal
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou 510260, China; (A.I.); (A.A.)
- Institute of Molecular Biology and Biotechnology, The University of Lahore, 1-Km Defense Road, Lahore 54000, Pakistan
| | - Ziyad Abdul Qadir
- Honeybee Research Institute, National Agricultural Research Centre, Park Road, Islamabad 45500, Pakistan;
- Department of Entomology and Wildlife Ecology, University of Delaware, Newark, DE 19716, USA
| | - Jun Li
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou 510260, China; (A.I.); (A.A.)
- Correspondence:
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12
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Tehan R, Blount RR, Goold RL, Mattos DR, Spatafora NR, Tabima JF, Gazis R, Wang C, Ishmael JE, Spatafora JW, McPhail KL. Tolypocladamide H and the Proposed Tolypocladamide NRPS in Tolypocladium Species. JOURNAL OF NATURAL PRODUCTS 2022; 85:1363-1373. [PMID: 35500108 PMCID: PMC9150700 DOI: 10.1021/acs.jnatprod.2c00153] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The genome of entomopathogenic fungus Tolypocladium inflatum Gams encodes 43 putative biosynthetic gene clusters for specialized metabolites, although genotype-phenotype linkages have been reported only for the cyclosporins and fumonisins. T. inflatum was cultured in defined minimal media, supplemented with or without one of nine different amino acids. Acquisition of LC-MS/MS data for molecular networking and manual analysis facilitated annotation of putative known and unknown metabolites. These data led us to target a family of peptaibols and guided the isolation and purification of tolypocladamide H (1), which showed modest antibacterial activity and toxicity to mammalian cells at micromolar concentrations. HRMS/MS, NMR, and advanced Marfey's analysis were used to assign the structure of 1 as a peptaibol containing 4-[(E)-2-butenyl]-4-methyl-l-threonine (Bmt), a hallmark structural motif of the cyclosporins. LC-MS detection of homologous tolypocladamide metabolites and phylogenomic analyses of peptaibol biosynthetic genes in other cultured Tolypocladium species allowed assignment of a putative tolypocladamide nonribosomal peptide synthetase gene.
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Affiliation(s)
- Richard
M. Tehan
- Department
of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, Oregon 97331, United States
| | - Rheannon R. Blount
- Department
of Botany and Plant Pathology, College of Agricultural and Life Sciences, Oregon State University, Corvallis, Oregon 97331, United States
| | - Ryan L. Goold
- Department
of Botany and Plant Pathology, College of Agricultural and Life Sciences, Oregon State University, Corvallis, Oregon 97331, United States
| | - Daphne R. Mattos
- Department
of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, Oregon 97331, United States
| | - Nicolas R. Spatafora
- Department
of Botany and Plant Pathology, College of Agricultural and Life Sciences, Oregon State University, Corvallis, Oregon 97331, United States
| | - Javier F. Tabima
- Department
of Botany and Plant Pathology, College of Agricultural and Life Sciences, Oregon State University, Corvallis, Oregon 97331, United States
- Department
of Biology, Clark University, Worcester, Massachusetts 01610, United States
| | - Romina Gazis
- Department
of Plant Pathology, Tropical Research and Education Center, University of Florida, Homestead, Florida 33031, United States
| | - Chengshu Wang
- Key
Laboratory of Insect Developmental and Evolutionary Biology, CAS Center
for Excellence in Molecular Plant Sciences, Shanghai Institute of
Plant Physiology and Ecology, Chinese Academy
of Sciences, Shanghai 200032, People’s Republic
of China
| | - Jane E. Ishmael
- Department
of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, Oregon 97331, United States
| | - Joseph W. Spatafora
- Department
of Botany and Plant Pathology, College of Agricultural and Life Sciences, Oregon State University, Corvallis, Oregon 97331, United States
- Tel: +1 541 737 8134. E-mail:
| | - Kerry L. McPhail
- Department
of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, Oregon 97331, United States
- Tel: +1 541 737 5808. E-mail:
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The Entomopathogenic Fungus Beauveria bassiana Shows Its Toxic Side within Insects: Expression of Genes Encoding Secondary Metabolites during Pathogenesis. J Fungi (Basel) 2022; 8:jof8050488. [PMID: 35628744 PMCID: PMC9143124 DOI: 10.3390/jof8050488] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 05/05/2022] [Accepted: 05/06/2022] [Indexed: 01/23/2023] Open
Abstract
Entomopathogenic fungi are extensively used for the control of insect pests worldwide. Among them, Beauveria bassiana (Ascomycota: Hypocreales) produce a plethora of toxic secondary metabolites that either facilitate fungal invasion or act as immunosuppressive compounds. These toxins have different chemical natures, such as nonribosomal peptides and polyketides. Even though their precise role is poorly understood, they are usually linked to virulence. These fungal secondary metabolites are produced by the expression of gene clusters encoding the various proteins needed for their biosynthesis. Each cluster includes synthetases for nonribosomal peptides (NRPS), polyketides (PKS), or hybrid NRPS–PKS genes. The aim of this review is to summarize the information available from transcriptomics and quantitative PCR studies related to the expression of B. bassiana NRPS and PKS genes inside different insects as the infection progresses; as for the host immune response, to help understand the mechanisms that these toxins trigger as virulence factors, antimicrobials, or immunosuppressives within the context of a fungus–insect interaction.
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14
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Genomic and Experimental Analysis of the Insecticidal Factors Secreted by the Entomopathogenic Fungus Beauveria pseudobassiana RGM 2184. J Fungi (Basel) 2022; 8:jof8030253. [PMID: 35330256 PMCID: PMC8952764 DOI: 10.3390/jof8030253] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 02/22/2022] [Accepted: 02/26/2022] [Indexed: 02/04/2023] Open
Abstract
The entomopathogenic fungus Beauveria pseudobassiana strain RGM 2184 can reach a maximum efficacy of 80% against the quarantine pest Lobesia botrana in field assays. In this study, the RGM 2184 genome was sequenced, and genome mining analyses were performed to predict the factors involved in its insecticidal activity. Additionally, the metabolic profiling of the RMG 2184 culture’s supernatants was analyzed by mass spectrometry, and the insecticidal activity from one of these extracts was evaluated in Galleria mellonella larvae. The genome analysis resulted in 114 genes encoding for extracellular enzymes, four biosynthetic gene clusters reported as producers of insecticidal and bactericidal factors (oosporein, beauvericin, desmethylbassianin, and beauveriolide), 20 toxins, and at least 40 undescribed potential biocontrol factors (polyketides and nonribosomal peptides). Comparative genomic analysis revealed that 65–95% of these genes are Beauveria genus-specific. Metabolic profiling of supernatant extracts from RGM 2184 cultures exhibited secondary metabolites such as beauveriolide, oosporein, inflatin C, and bassiatin. However, a number of detected metabolites still remain undescribed. The metabolite extract caused 79% mortality of Galleria mellonella larvae at 28 days. The results of this research lay the groundwork for the study of new insecticidal molecules.
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15
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Zhang FL, Feng T. Diterpenes Specially Produced by Fungi: Structures, Biological Activities, and Biosynthesis (2010–2020). J Fungi (Basel) 2022; 8:jof8030244. [PMID: 35330246 PMCID: PMC8951520 DOI: 10.3390/jof8030244] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 02/25/2022] [Accepted: 02/27/2022] [Indexed: 12/11/2022] Open
Abstract
Fungi have traditionally been a very rewarding source of biologically active natural products, while diterpenoids from fungi, such as the cyathane-type diterpenoids from Cyathus and Hericium sp., the fusicoccane-type diterpenoids from Fusicoccum and Alternaria sp., the guanacastane-type diterpenoids from Coprinus and Cercospora sp., and the harziene-type diterpenoids from Trichoderma sp., often represent unique carbon skeletons as well as diverse biological functions. The abundances of novel skeletons, biological activities, and biosynthetic pathways present new opportunities for drug discovery, genome mining, and enzymology. In addition, diterpenoids peculiar to fungi also reveal the possibility of differing biological evolution, although they have similar biosynthetic pathways. In this review, we provide an overview about the structures, biological activities, evolution, organic synthesis, and biosynthesis of diterpenoids that have been specially produced by fungi from 2010 to 2020. We hope this review provides timely illumination and beneficial guidance for future research works of scholars who are interested in this area.
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Inductive Production of the Iron-Chelating 2-Pyridones Benefits the Producing Fungus To Compete for Diverse Niches. mBio 2021; 12:e0327921. [PMID: 34903054 PMCID: PMC8669486 DOI: 10.1128/mbio.03279-21] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Diverse 2-pyridone alkaloids have been identified with an array of biological and pharmaceutical activities, including the development of drugs. However, the biosynthetic regulation and chemical ecology of 2-pyridones remain largely elusive. Here, we report the inductive activation of the silent polyketide synthase-nonribosomal peptide synthetase (PKS-NRPS) (tenS) gene cluster for the biosynthesis of the tenellin-type 2-pyridones in the insect-pathogenic fungus Beauveria bassiana when cocultured with its natural competitor fungus Metarhizium robertsii. A pathway-specific transcription factor, tenR, was identified, and the overexpression of tenR well expanded the biosynthetic mechanism of 15-hydroxytenellin (15-HT) and its derivatives. In particular, a tandemly linked glycosyltransferase-methyltransferase gene pair located outside the tenS gene cluster was verified to mediate the rare and site-specific methylglucosylation of 15-HT at its N-OH residue. It was evident that both tenellin and 15-HT can chelate iron, which could benefit B. bassiana to outcompete M. robertsii in cocultures and to adapt to iron-replete and -depleted conditions. Relative to the wild-type strain, the deletion of tenS had no obvious negative effect on fungal virulence, but the overexpression of tenR could substantially increase fungal pathogenicity toward insect hosts. The results of this study well advance the understanding of the biosynthetic machinery and chemical ecology of 2-pyridones.
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17
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Wang H, Peng H, Li W, Cheng P, Gong M. The Toxins of Beauveria bassiana and the Strategies to Improve Their Virulence to Insects. Front Microbiol 2021; 12:705343. [PMID: 34512581 PMCID: PMC8430825 DOI: 10.3389/fmicb.2021.705343] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 07/27/2021] [Indexed: 01/18/2023] Open
Abstract
The long-term and excessive usage of pesticides is an enormous burden on the environment, which also increases pest resistance. To overcome this problem, research and application of entomopathogenic fungi, which are both environmentally friendly and cause lower resistance, have gained great momentum. Entomopathogenic fungi have a wide range of prospects. Apart from Bacillus thuringiensis, Beauveria bassiana is the most studied biopesticide. After invading insect hosts, B. bassiana produces a variety of toxins, which are secondary metabolites such as beauvericin, bassianin, bassianolide, beauverolides, tenellin, oosporein, and oxalic acid. These toxins help B. bassiana to parasitize and kill the hosts. This review unequivocally considers beauveria toxins highly promising and summarizes their attack mechanism(s) on the host insect immune system. Genetic engineering strategies to improve toxin principles, genes, or virulent molecules of B. bassiana have also been discussed. Lastly, we discuss the future perspective of Beauveria toxin research, including newly discovered toxins.
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Affiliation(s)
- Haiyang Wang
- Shandong Institute of Parasitic Diseases, Shandong First Medical University & Shandong Academy of Medical Sciences, Jining, China.,College of Forensic Medicine and Laboratory Medicine, Jining Medical University, Jining, China
| | - Hui Peng
- Shandong Institute of Parasitic Diseases, Shandong First Medical University & Shandong Academy of Medical Sciences, Jining, China
| | - Wenjuan Li
- College of Forensic Medicine and Laboratory Medicine, Jining Medical University, Jining, China
| | - Peng Cheng
- Shandong Institute of Parasitic Diseases, Shandong First Medical University & Shandong Academy of Medical Sciences, Jining, China
| | - Maoqing Gong
- Shandong Institute of Parasitic Diseases, Shandong First Medical University & Shandong Academy of Medical Sciences, Jining, China
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18
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Ophiocordyceps flavida sp. nov. (Ophiocordycipitaceae), a new species from Thailand associated with Pseudogibellula formicarum (Cordycipitaceae), and their bioactive secondary metabolites. Mycol Prog 2021. [DOI: 10.1007/s11557-021-01683-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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19
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Liu S, Fan W, Ren J, Wang W, Liu X, Liang Y, Wei T, Li E. Peniterpenoids A-C, new sesquiterpenoid metabolites from a wheat cyst nematode Penicillium janthinellum. Fitoterapia 2020; 148:104801. [PMID: 33309650 DOI: 10.1016/j.fitote.2020.104801] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 12/04/2020] [Accepted: 12/07/2020] [Indexed: 11/16/2022]
Abstract
Three new sesquiterpenoids, peniterpenoids A - C (1-3), together with six known metabolites (4-9) were isolated from an entomogenous fungus Penicillium janthinellum (LB1.20090001) collected from a wheat cyst nematode. The structures of the new compounds were elucidated based on NMR and HRESIMS spectroscopic analyses. The absolute configuration of the C-8 secondary alcohol of peniterpenoid B (2) was determined by [Rh2(OCOCF3)4]-induced ECD experiment. Subsequently, the antimicrobial and DPPH scavenging activities were determined. Compounds 6-8 exhibited moderate antibacterial activities against Staphylococcus aureus (CGMCC1.2465) with MIC values of 25.0, 50.0 and 12.5 μg/mL, respectively.
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Affiliation(s)
- Sushi Liu
- Beijing Key Laboratory of Bioactive Substance and Functional Foods, Beijing Union University, Beijing 100191, China; State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Wenwen Fan
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Jinwei Ren
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Wenzhao Wang
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Xingzhong Liu
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yonghong Liang
- Key Laboratory of Modern Preparation of TCM, Ministry of Education, Jiangxi University of Traditional Chinese Medicine, Nanchang 330004, China
| | - Tao Wei
- Beijing Key Laboratory of Bioactive Substance and Functional Foods, Beijing Union University, Beijing 100191, China.
| | - Erwei Li
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
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20
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St. Leger RJ, Wang JB. Metarhizium: jack of all trades, master of many. Open Biol 2020; 10:200307. [PMID: 33292103 PMCID: PMC7776561 DOI: 10.1098/rsob.200307] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 11/09/2020] [Indexed: 02/06/2023] Open
Abstract
The genus Metarhizium and Pochonia chlamydosporia comprise a monophyletic clade of highly abundant globally distributed fungi that can transition between long-term beneficial associations with plants to transitory pathogenic associations with frequently encountered protozoans, nematodes or insects. Some very common 'specialist generalist' species are adapted to particular soil and plant ecologies, but can overpower a wide spectrum of insects with numerous enzymes and toxins that result from extensive gene duplications made possible by loss of meiosis and associated genome defence mechanisms. These species use parasexuality instead of sex to combine beneficial mutations from separate clonal individuals into one genome (Vicar of Bray dynamics). More weakly endophytic species which kill a narrow range of insects retain sexuality to facilitate host-pathogen coevolution (Red Queen dynamics). Metarhizium species can fit into numerous environments because they are very flexible at the genetic, physiological and ecological levels, providing tractable models to address how new mechanisms for econutritional heterogeneity, host switching and virulence are acquired and relate to diverse sexual life histories and speciation. Many new molecules and functions have been discovered that underpin Metarhizium associations, and have furthered our understanding of the crucial ecology of these fungi in multiple habitats.
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21
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Isolation of Beauveria bassiana from the Chagas Disease Vector Triatoma infestans in the Gran Chaco Region of Argentina: Assessment of Gene Expression during Host-Pathogen Interaction. J Fungi (Basel) 2020; 6:jof6040219. [PMID: 33053646 PMCID: PMC7711898 DOI: 10.3390/jof6040219] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 10/07/2020] [Accepted: 10/09/2020] [Indexed: 12/31/2022] Open
Abstract
A native strain of the entomopathogenic fungus Beauveria bassiana (Bb-C001) was isolated from a naturally infected Triatoma infestans, Klug (Hemiptera: Reduviidae) adult cadaver in the Gran Chaco region, Salta province, Argentina. The isolate was both phenotypic and molecularly characterized in a context of fungus-insect interaction, by measuring the expression pattern of toxin genes during infection and immune response of T. infestans. The commercial strain GHA of B. bassiana, which was previously used in field interventions to control these vectors, was used as reference in this study. The phylogenetic trees based on both ribosomal internal transcribed spacer (ITS) and elongation factor 1-alpha (EF1-α) indicated that Bb-C001 fits into a B. bassiana cluster, and the sequence-characterized amplified regions (SCAR) showed that Bb-C001 is different from the GHA strain. There were no differences between both strains regarding viability, radial growth, and conidia production, either in the median survival time or insect mortality. However, Bb-C001 showed a higher expression than GHA of the bassianolide synthetase gene (BbbslS) during infection, and similar levels of the beauvericin synthetase gene (BbbeaS). Immune-related genes of T. infestans nymphs (limpet-2 and defensin-1, -2, and -6) were later expressed and thus insects failed to stop the infection process. These results showed that B. bassiana Bb-C001 is a promised fungal strain to be incorporated in the current biological control programs of T. infestans in Salta province, Argentina.
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