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Zhou J, Wang D, Wu Q, Jiang Y, Yan J, Wu L, Li S, Niu X. Rare NRPS Gene Cluster for Desferriferrichrome Biosynthesis Controls the Conflict between Trap Formation and Nematicidal Activity in Arthrobotrys oligospora. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:3560-3571. [PMID: 38340066 DOI: 10.1021/acs.jafc.3c08354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/12/2024]
Abstract
The formation of the trapping device induced by nematodes has been assumed as an indicator for a switch from saprophytic to predacious lifestyles for nematode-trapping fungi. However, fungal nematocidal activity is not completely synonymous with fungal trap formation. We found that the predominant nematode-trapping fungus Arthrobotrys oligospora harbored a rare NRPS (Ao415) gene cluster that was mainly distributed in nematode-trapping fungi. The gene Ao415 putatively encodes a protein with a unique domain organization, distinct from other NRPSs in other fungi. Mutation of the two key biosynthetic genes Ao415 and Ao414 combined with nontarget metabolic analysis revealed that the Ao415 gene cluster was responsible for the biosynthesis of a hydroxamate siderophore, desferriferrichrome (1). Lack of desferriferrichrome (1) and its hydroxamate precursor (3) could lead to significantly increased Fe3+ content, which induced fungal trap formation without a nematode inducer. Furthermore, the addition of Fe3+ strongly improved fungal trap formation but deleteriously caused broken traps. The addition of 1 significantly attenuated trap formation but enhanced fungal nematicidal activity. Our findings indicate that iron is a key factor for trap formation and provide a new insight into the underlying mechanism of siderophores in nematode-trapping fungi.
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Affiliation(s)
- Jiao Zhou
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, School of Life Sciences, Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming 650091, P. R. China
| | - DongLou Wang
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, School of Life Sciences, Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming 650091, P. R. China
| | - QunFu Wu
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, School of Life Sciences, Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming 650091, P. R. China
| | - Yang Jiang
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, School of Life Sciences, Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming 650091, P. R. China
| | - JunXian Yan
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, School of Life Sciences, Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming 650091, P. R. China
| | - Li Wu
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, School of Life Sciences, Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming 650091, P. R. China
| | - ShuHong Li
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, School of Life Sciences, Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming 650091, P. R. China
| | - XueMei Niu
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, School of Life Sciences, Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming 650091, P. R. China
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Zhao N, Zhu M, Liu Q, Shen Y, Duan S, Zhu L, Yang J. AoPrdx2 Regulates Oxidative Stress, Reactive Oxygen Species, Trap Formation, and Secondary Metabolism in Arthrobotrys oligospora. J Fungi (Basel) 2024; 10:110. [PMID: 38392782 PMCID: PMC10890406 DOI: 10.3390/jof10020110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 01/23/2024] [Accepted: 01/25/2024] [Indexed: 02/24/2024] Open
Abstract
Prdx2 is a peroxiredoxin (Prx) family protein that protects cells from attack via reactive oxygen species (ROS), and it has an important role in improving the resistance and scavenging capacity of ROS in fungi. Arthrobotrys oligospora is a widespread nematode-trapping fungus that can produce three-dimensional nets to capture and kill nematodes. In this study, AoPrdx2, a homologous protein of Prx5, was investigated in A. oligospora via gene disruption, phenotypic analysis, and metabolomics. The deletion of Aoprdx2 resulted in an increase in the number of mycelial septa and a reduction in the number of nuclei and spore yield. Meanwhile, the absence of Aoprdx2 increased sensitivity to oxidative stresses, whereas the ∆Aoprdx2 mutant strain resulted in higher ROS levels than that of the wild-type (WT) strain. In particular, the inactivation of Aoprdx2 severely influenced trap formation and pathogenicity; the number of traps produced by the ∆Aoprdx2 mutant strain was remarkably reduced and the number of mycelial rings of traps in the ∆Aoprdx2 mutant strain was less than that of the WT strain. In addition, the abundance of metabolites in the ∆Aoprdx2 mutant strain was significantly downregulated compared with the WT strain. These results indicate that AoPrdx2 plays an indispensable role in the scavenging of ROS, trap morphogenesis, and secondary metabolism.
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Affiliation(s)
- Na Zhao
- State Key Laboratory for Conservation and Utilization of Bio-Resources, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming 650091, China
| | - Meichen Zhu
- State Key Laboratory for Conservation and Utilization of Bio-Resources, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming 650091, China
| | - Qianqian Liu
- State Key Laboratory for Conservation and Utilization of Bio-Resources, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming 650091, China
| | - Yanmei Shen
- State Key Laboratory for Conservation and Utilization of Bio-Resources, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming 650091, China
| | - Shipeng Duan
- State Key Laboratory for Conservation and Utilization of Bio-Resources, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming 650091, China
| | - Lirong Zhu
- State Key Laboratory for Conservation and Utilization of Bio-Resources, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming 650091, China
| | - Jinkui Yang
- State Key Laboratory for Conservation and Utilization of Bio-Resources, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming 650091, China
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3
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Gu T, Lu H, Liu H, Zhang G, Wang Y. Function discovery of a non-ribosomal peptide synthetase-like encoding gene in the nematode-trapping fungus Arthrobotrys oligospora. Front Microbiol 2023; 14:1210288. [PMID: 37520361 PMCID: PMC10373296 DOI: 10.3389/fmicb.2023.1210288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Accepted: 06/27/2023] [Indexed: 08/01/2023] Open
Abstract
In this study, the function of a non-ribosomal peptide synthetase-like (NRPS-like) encoding gene AOL_s00188g306 (g306) was investigated to reveal the association between NRPS and nematocidal activity in the nematode-trapping fungus Arthrobotrys oligospora. Sequence analysis indicated that the encoded product of g306 is an adenylation domain of non-ribosomal peptide synthetases and extended short-chain dehydrogenase/reductase domain-containing proteins, and displays a wide substrate spectrum. The Δg306 mutants were more sensitive to chemical stressors than the wild type. Disruption of g306 impeded the nematocidal efficiency of A. oligospora. Metabolomics analysis showed that secondary metabolite biosynthesis and lipid metabolism were altered in the mutants. The phenotypic changes in the mutants can be attributed to the down-regulation of various metabolites, including fatty acyls, prenol lipids, steroidsand steroid derivative, and amino acid derivatives, identified in the present study. This study investigated the association between the non-ribosomal polypeptide-encoding gene g306 and nematicidal activity in A. oligospora, providing a reference for resolving the predation mechanism of nematode-trapping fungus.
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Affiliation(s)
- Tiantian Gu
- School of Life Sciences, Anhui University, Hefei, Anhui, China
- Key Laboratory of Human Microenvironment and Precision Medicine of Anhui Higher Education Institutes, Anhui University, Hefei, Anhui, China
| | - Hengqian Lu
- School of Life Sciences, Anhui University, Hefei, Anhui, China
- Key Laboratory of Human Microenvironment and Precision Medicine of Anhui Higher Education Institutes, Anhui University, Hefei, Anhui, China
| | - Huiwen Liu
- School of Life Sciences, Anhui University, Hefei, Anhui, China
- Key Laboratory of Human Microenvironment and Precision Medicine of Anhui Higher Education Institutes, Anhui University, Hefei, Anhui, China
| | - Guanghui Zhang
- School of Life Sciences, Anhui University, Hefei, Anhui, China
- Key Laboratory of Human Microenvironment and Precision Medicine of Anhui Higher Education Institutes, Anhui University, Hefei, Anhui, China
| | - Yongzhong Wang
- School of Life Sciences, Anhui University, Hefei, Anhui, China
- Key Laboratory of Human Microenvironment and Precision Medicine of Anhui Higher Education Institutes, Anhui University, Hefei, Anhui, China
- Anhui Key Laboratory of Modern Biomanufacturing, Hefei, Anhui, China
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4
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Abstract
Nematode-trapping fungi (NTF) are the majority of carnivorous microbes to capture nematodes through diverse and sophisticated trapping organs derived from hyphae. They can adopt carnivorous lifestyles in addition to saprophytism to obtain extra-nutrition from nematodes. As a special group of fungi, the NTF are not only excellent model organism for studying lifestyle transition of fungi but also natural resources of exploring biological control of nematodes. However, the carnivorous mechanism of NTF remains poorly understood. Nowadays, the omics studies of NTF have provided numerous genes and pathways that are associated with the phenotypes of carnivorous traits, which need molecular tools to verify. Here, we review the development and progress of gene manipulation tools in NTF, including methodology and strategy of transformation, random gene mutagenesis methods and target gene mutagenesis methods. The principle and practical approach for each method was summarized and discussed, and the basic operational flow for each tool was described. This paper offers a clear reference and instruction for researchers who work on NTF as well as other group of fungi.
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Affiliation(s)
- Shunxian Wang
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Science, Nankai University, Tianjin, China
| | - Xingzhong Liu
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Science, Nankai University, Tianjin, China
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
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Deletion of a Putative GPI-Anchored Protein-Encoding Gene Aog185 Impedes the Growth and Nematode-Trapping Efficiency of Arthrobotrys oligospora by Disrupting Transmembrane Transport Homeostasis. Cell Microbiol 2022. [DOI: 10.1155/2022/8738290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Nematode-trapping fungus (NTF) is a crucial predator of nematodes, which can capture nematodes by developing specific trapping devices. However, there is limited understanding of the role and mechanism of cell surface proteins attached to the surface of mycelia or trapping cells. Here, the effects of a putative GPI-anchored protein-encoding gene Aog185 on the growth and nematode-trapping efficiency of A. oligospora were investigated. Compared to the wild-type (WT) strain, the ΔAog185 mutant grew more slowly, exhibited a 20% decrease in conidiation, delayed conidial germination, generated fewer traps, attenuated nematode trapping efficiency, and was more sensitive to chemical stressors. Transcriptomic analysis indicated that a large number of transmembrane transport-related genes were differentially expressed between the WT and ΔAog185 mutant strains. Aog185 deletion could damage the intrinsic components of the membrane and cytoskeleton. Specifically, knockout of Aog185 disrupted transmembrane transport homeostasis during the phagocytosis, cell autophagy, and oxidative phosphorylation processes, which were associated with the fusion of cells and organelle membranes, transport of ions and substrates, and energy metabolism. Hence, the putative GPI-anchored protein-encoding gene Aog185 may contribute to the lifestyle switch of NTF and nematode capture, and the effect of Aog185 gene on cell transmembrane transport is considered key to this process. Our findings provide new insights into the mechanism of Aog185 gene during the process of nematode trapping by NTF.
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Li X, Zhu M, Liu Y, Yang L, Yang J. Aoatg11 and Aoatg33 are indispensable for mitophagy, and contribute to conidiation, the stress response, and pathogenicity in the nematode-trapping fungus Arthrobotrys oligospora. Microbiol Res 2022; 266:127252. [DOI: 10.1016/j.micres.2022.127252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 10/31/2022] [Accepted: 10/31/2022] [Indexed: 11/06/2022]
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7
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Zhu MC, Li XM, Zhao N, Yang L, Zhang KQ, Yang JK. Regulatory Mechanism of Trap Formation in the Nematode-Trapping Fungi. J Fungi (Basel) 2022; 8:jof8040406. [PMID: 35448637 PMCID: PMC9031305 DOI: 10.3390/jof8040406] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Revised: 04/13/2022] [Accepted: 04/14/2022] [Indexed: 01/21/2023] Open
Abstract
Nematode-trapping (NT) fungi play a significant role in the biological control of plant- parasitic nematodes. NT fungi, as a predator, can differentiate into specialized structures called “traps” to capture, kill, and consume nematodes at a nutrient-deprived condition. Therefore, trap formation is also an important indicator that NT fungi transition from a saprophytic to a predacious lifestyle. With the development of gene knockout and multiple omics such as genomics, transcriptomics, and metabolomics, increasing studies have tried to investigate the regulation mechanism of trap formation in NT fungi. This review summarizes the potential regulatory mechanism of trap formation in NT fungi based on the latest findings in this field. Signaling pathways have been confirmed to play an especially vital role in trap formation based on phenotypes of various mutants and multi-omics analysis, and the involvement of small molecule compounds, woronin body, peroxisome, autophagy, and pH-sensing receptors in the formation of traps are also discussed. In addition, we also highlight the research focus for elucidating the mechanism underlying trap formation of NT fungi in the future.
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Jiang KX, Liu QQ, Bai N, Zhu MC, Zhang KQ, Yang JK. AoSsk1, a Response Regulator Required for Mycelial Growth and Development, Stress Responses, Trap Formation, and the Secondary Metabolism in Arthrobotrys oligospora. J Fungi (Basel) 2022; 8:jof8030260. [PMID: 35330262 PMCID: PMC8952730 DOI: 10.3390/jof8030260] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 03/01/2022] [Accepted: 03/02/2022] [Indexed: 02/06/2023] Open
Abstract
Ssk1, a response regulator of the two-component signaling system, plays an important role in the cellular response to hyperosmotic stress in fungi. Herein, an ortholog of ssk1 (Aossk1) was characterized in the nematode-trapping fungus Arthrobotrys oligospora using gene disruption and multi-phenotypic comparison. The deletion of Aossk1 resulted in defective growth, deformed and swollen hyphal cells, an increased hyphal septum, and a shrunken nucleus. Compared to the wild-type (WT) strain, the number of autophagosomes and lipid droplets in the hyphal cells of the ΔAossk1 mutant decreased, whereas their volumes considerably increased. Aossk1 disruption caused a 95% reduction in conidial yield and remarkable defects in tolerance to osmotic and oxidative stress. Meanwhile, the transcript levels of several sporulation-related genes were significantly decreased in the ΔAossk1 mutant compared to the WT strain, including abaA, brlA, flbC, fluG, and rodA. Moreover, the loss of Aossk1 resulted in a remarkable increase in trap formation and predation efficiency. In addition, many metabolites were markedly downregulated in the ΔAossk1 mutant compared to the WT strain. Our results highlight that AoSsk1 is a crucial regulator of asexual development, stress responses, the secondary metabolism, and pathogenicity, and can be useful in probing the regulatory mechanism underlying the trap formation and lifestyle switching of nematode-trapping fungi.
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Affiliation(s)
- Ke-Xin Jiang
- State Key Laboratory for Conservation and Utilization of Bio-Resources, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming 650091, China
| | - Qian-Qian Liu
- State Key Laboratory for Conservation and Utilization of Bio-Resources, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming 650091, China
| | - Na Bai
- State Key Laboratory for Conservation and Utilization of Bio-Resources, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming 650091, China
| | - Mei-Chen Zhu
- State Key Laboratory for Conservation and Utilization of Bio-Resources, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming 650091, China
| | - Ke-Qin Zhang
- State Key Laboratory for Conservation and Utilization of Bio-Resources, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming 650091, China
| | - Jin-Kui Yang
- State Key Laboratory for Conservation and Utilization of Bio-Resources, Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming 650091, China
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9
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Yu X, Hu X, Pop M, Wernet N, Kirschhöfer F, Brenner-Weiß G, Keller J, Bunzel M, Fischer R. Fatal attraction of Caenorhabditis elegans to predatory fungi through 6-methyl-salicylic acid. Nat Commun 2021; 12:5462. [PMID: 34526503 PMCID: PMC8443565 DOI: 10.1038/s41467-021-25535-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 08/12/2021] [Indexed: 11/30/2022] Open
Abstract
Salicylic acid is a phenolic phytohormone which controls plant growth and development. A methyl ester (MSA) derivative thereof is volatile and involved in plant-insect or plant-plant communication. Here we show that the nematode-trapping fungus Duddingtonia flagrans uses a methyl-salicylic acid isomer, 6-MSA as morphogen for spatiotemporal control of trap formation and as chemoattractant to lure Caenorhabditis elegans into fungal colonies. 6-MSA is the product of a polyketide synthase and an intermediate in the biosynthesis of arthrosporols. The polyketide synthase (ArtA), produces 6-MSA in hyphal tips, and is uncoupled from other enzymes required for the conversion of 6-MSA to arthrosporols, which are produced in older hyphae. 6-MSA and arthrosporols both block trap formation. The presence of nematodes inhibits 6-MSA and arthrosporol biosyntheses and thereby enables trap formation. 6-MSA and arthrosporols are thus morphogens with some functions similar to quorum-sensing molecules. We show that 6-MSA is important in interkingdom communication between fungi and nematodes.
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Affiliation(s)
- Xi Yu
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute of Applied Biosciences, Department of Microbiology, Fritz-Haber-Weg 4, Karlsruhe, Germany
- Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai, China
| | - Xiaodi Hu
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute of Applied Biosciences, Department of Microbiology, Fritz-Haber-Weg 4, Karlsruhe, Germany
| | - Maria Pop
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute of Applied Biosciences, Department of Microbiology, Fritz-Haber-Weg 4, Karlsruhe, Germany
| | - Nicole Wernet
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute of Applied Biosciences, Department of Microbiology, Fritz-Haber-Weg 4, Karlsruhe, Germany
| | - Frank Kirschhöfer
- Karlsruhe Institute of Technology (KIT) - North Campus, Institute of Functional Interfaces, Department of Bioengineering and Biosystems, Eggenstein Leopoldshafen, Germany
| | - Gerald Brenner-Weiß
- Karlsruhe Institute of Technology (KIT) - North Campus, Institute of Functional Interfaces, Department of Bioengineering and Biosystems, Eggenstein Leopoldshafen, Germany
| | - Julia Keller
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute of Applied Biosciences, Department of Food Chemistry and Phytochemistry, Adenauerring 20 A, Karlsruhe, Germany
| | - Mirko Bunzel
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute of Applied Biosciences, Department of Food Chemistry and Phytochemistry, Adenauerring 20 A, Karlsruhe, Germany
| | - Reinhard Fischer
- Karlsruhe Institute of Technology (KIT) - South Campus, Institute of Applied Biosciences, Department of Microbiology, Fritz-Haber-Weg 4, Karlsruhe, Germany.
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Bai N, Zhang G, Wang W, Feng H, Yang X, Zheng Y, Yang L, Xie M, Zhang KQ, Yang J. Ric8 acts as a regulator of G-protein signalling required for nematode-trapping lifecycle of Arthrobotrys oligospora. Environ Microbiol 2021; 24:1714-1730. [PMID: 34431203 DOI: 10.1111/1462-2920.15735] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 08/20/2021] [Accepted: 08/20/2021] [Indexed: 11/29/2022]
Abstract
Resistance to inhibitors of cholinesterase 8 (Ric8) is a conserved guanine nucleotide exchange factor that is involved in the regulation of G-protein signalling in filamentous fungi. Here, we characterized an orthologous Ric8 (AoRic8) in Arthrobotrys oligospora by multi-omics analyses. The Aoric8 deletion (ΔAoric8) mutants lost an ability to produce traps essential for nematode predation, accompanied by a marked reduction in cAMP level. Yeast two-hybrid assay revealed that AoRic8 interacted with G-protein subunit Gα1. Moreover, the mutants were compromised in mycelia growth, conidiation, stress resistance, endocytosis, cellular components and intrahyphal hyphae. Revealed by transcriptomic analysis differentially upregulated genes in the absence of Aoric8 were involved in cell cycle, DNA replication and recombination during trap formation while downregulated genes were primarily involved in organelles, carbohydrate metabolism and amino acid metabolism. Metabolomic analysis showed that many compounds were markedly downregulated in ΔAoric8 mutants versus the wild-type strain. Our results demonstrated a crucial role for AoRic8 in the fungal growth, environmental adaption and nematode predation through control of cell cycle, organelle and secondary metabolism by G-protein signalling.
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Affiliation(s)
- Na Bai
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, 650091, P. R. China.,School of Life Sciences, Yunnan University, Kunming, 650091, P. R. China
| | - Guosheng Zhang
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, 650091, P. R. China.,School of Life Sciences, Yunnan University, Kunming, 650091, P. R. China
| | - Wenjie Wang
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, 650091, P. R. China.,School of Life Sciences, Yunnan University, Kunming, 650091, P. R. China
| | - Huihua Feng
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, 650091, P. R. China.,School of Life Sciences, Yunnan University, Kunming, 650091, P. R. China
| | - Xuewei Yang
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, 650091, P. R. China.,School of Life Sciences, Yunnan University, Kunming, 650091, P. R. China
| | - Yaqing Zheng
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, 650091, P. R. China.,School of Life Sciences, Yunnan University, Kunming, 650091, P. R. China
| | - Le Yang
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, 650091, P. R. China.,School of Life Sciences, Yunnan University, Kunming, 650091, P. R. China
| | - Meihua Xie
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, 650091, P. R. China
| | - Ke-Qin Zhang
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, 650091, P. R. China.,School of Life Sciences, Yunnan University, Kunming, 650091, P. R. China
| | - Jinkui Yang
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University, Kunming, 650091, P. R. China.,School of Life Sciences, Yunnan University, Kunming, 650091, P. R. China
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11
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He ZQ, Wang LJ, Wang YJ, Chen YH, Wen Y, Zhang KQ, Niu XM. Polyketide Synthase-Terpenoid Synthase Hybrid Pathway Regulation of Trap Formation through Ammonia Metabolism Controls Soil Colonization of Predominant Nematode-Trapping Fungus. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:4464-4479. [PMID: 33823587 DOI: 10.1021/acs.jafc.1c00771] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Polyketide synthase-terpenoid synthase (PKS-TPS) hybrid pathways for biosynthesis of unique sesquiterpenyl epoxy-cyclohexenoids (SECs) have been found to be widely distributed in plant pathogenic fungi. However, the natural and ecological functions of these pathways and their metabolites still remain cryptic. In this study, the whole PKS-TPS hybrid pathway in the predominant nematode-trapping fungus Arthrobotrys oligospora was first proposed according to all the intermediates and their derivatives from all the A. oligospora mutants with a deficiency in each gene involved in SEC biosynthesis. Most mutants displayed significantly increased trap formation which was correlated with alteration of the ammonia level. Further analysis revealed that the main metabolites involved in ammonia metabolism were largely increased in most mutants. However, significantly retarded colonization in soil were observed in most mutants compared to the wild-type strain due to significantly decreased antibacterial activities. Our results suggested that A. oligospora used the PKS-TPS hybrid pathway for fungal soil colonization via decreasing fungal nematode-capturing ability. This also provided solid evidence that boosting fungal colonization in soil was the secondary metabolite whose biosynthesis depended on a PKS-TPS hybrid pathway.
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Affiliation(s)
- Zhi-Qiang He
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of life Sciences, Yunnan University, Kunming, 650091, People's Republic of China
| | - Li-Jun Wang
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of life Sciences, Yunnan University, Kunming, 650091, People's Republic of China
| | - Yu-Jing Wang
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of life Sciences, Yunnan University, Kunming, 650091, People's Republic of China
| | - Yong-Hong Chen
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of life Sciences, Yunnan University, Kunming, 650091, People's Republic of China
| | - Ya Wen
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of life Sciences, Yunnan University, Kunming, 650091, People's Republic of China
| | - Ke-Qin Zhang
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of life Sciences, Yunnan University, Kunming, 650091, People's Republic of China
| | - Xue-Mei Niu
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of life Sciences, Yunnan University, Kunming, 650091, People's Republic of China
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12
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Khanna K, Kohli SK, Ohri P, Bhardwaj R. Plants-nematodes-microbes crosstalk within soil: A trade-off among friends or foes. Microbiol Res 2021; 248:126755. [PMID: 33845302 DOI: 10.1016/j.micres.2021.126755] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 03/18/2021] [Accepted: 03/27/2021] [Indexed: 11/28/2022]
Abstract
Plants interact with enormous biotic and abiotic components within ecosystem. For instance, microbes, insects, herbivores, animals, nematodes etc. In general, these interactions are studied independently with plants, that condenses only specific information about the interaction. However, the limitation to study the cross-interactions masks the collaborative role of organisms within ecosystem. Beneficial microbes are most prominent organisms that are needed to be studied due to their bidirectional nature towards plants. Fascinatingly, Plant-Parasitic Nematodes (PPNs) have been profoundly observed to cause mass destruction of agricultural crops worldwide. The huge demand for agriculture for present-day population requires optimization of production potential by curbing the damage caused by PPNs. Chemical nematicides combats their proliferation, but their extended usage has abruptly affected flora, fauna and human populations. Because of consistent pressing issues in regard to environment, the use of biocontrol agents are most favourable alternatives for managing agriculture. However, this association is somehow, tug of war, and understanding of plant-nematode-microbial relation would enable the agriculturists to monitor the overall development of plants along with limiting the use of agrochemicals. Soil microbes are contemporary bio-nematicides emerging in the market, that stimulates the plant growth and impedes PPNs populations. They form natural enemies and trap nematodes, henceforth, it is crucial to understand these interactions for ecological and biotechnological perspectives for commercial use. Moreover, acquiring the diversity of their relationship and molecular-based mechanisms, outlines their cascade of signaling events to serve as biotechnological ecosystem engineers. The omics based mechanisms encompassing hormone gene regulatory pathways and elicitors released by microbes are able to modulate pathogenesis-related (PR) genes within plants. This is achieved via Induced Systemic Resistance (ISR) or acquired systemic channels. Taking into account all these validations, the present review mainly advocates the relationship among microbes and nematodes in plants. It is believed that this review will boost zest and zeal within researchers to effectively understand the plant-nematodes-microbes relations and their ecological perspectives.
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Affiliation(s)
- Kanika Khanna
- Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, 143005, Punjab, India.
| | - Sukhmeen Kaur Kohli
- Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, 143005, Punjab, India
| | - Puja Ohri
- Department of Zoology, Guru Nanak Dev University, Amritsar, 143005, Punjab, India.
| | - Renu Bhardwaj
- Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, 143005, Punjab, India.
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13
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Teng LL, Song TY, Chen YH, Chen YG, Zhang KQ, Li SH, Niu XM. Novel Polyketide-Terpenoid Hybrid Metabolites from a Potent Nematicidal Arthrobotrys oligospora Mutant Δ AOL_s00215g278. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:11449-11458. [PMID: 32924475 DOI: 10.1021/acs.jafc.0c04713] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Here, we reported that detailed investigation on trace targeted metabolites from nematode-trapping fungus Arthrobotrys oligospora mutant with deletion of P450 gene AOL_s00215g278 led to isolation of 9 new polyketide-terpenoid hybrid derivatives, including four new glycosides of the key precursor farnesyl hydrotoluquinol (1) and, surprisingly, four new sesquiterpenyl epoxy-cyclohexenoids (SECs) analogues. Among them, two major target metabolites 1 and 14 displayed moderate nematode inhibitory ability. Moreover, the mutant lacking AOL_s00215g278 could form far more nematode-capturing traps within 6 h in contact with nematodes and show rapid potent nematicidal activity with killing 93.7% preys, though deletion of the P450 gene resulted in dramatic decrease in fungal colony growth and failure to produce fungal conidia. The results unequivocally revealed that gene AOL_s00215g278 should be involved in not only the SEC biosynthetic pathway in the nematode-trapping fungus A. oligospora but also fungal conidiation and nematicidal activity.
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Affiliation(s)
- Lin-Lin Teng
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Science, Yunnan University, Kunming 650091, People's Republic of China
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, P. R. China
| | - Tian-Yang Song
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Science, Yunnan University, Kunming 650091, People's Republic of China
| | - Yong-Hong Chen
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Science, Yunnan University, Kunming 650091, People's Republic of China
| | - Yue-Gui Chen
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Science, Yunnan University, Kunming 650091, People's Republic of China
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, P. R. China
| | - Ke-Qin Zhang
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Science, Yunnan University, Kunming 650091, People's Republic of China
| | - Sheng-Hong Li
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, P. R. China
| | - Xue-Mei Niu
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Science, Yunnan University, Kunming 650091, People's Republic of China
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14
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Chen YH, Liu X, Dai R, Ou X, Xu ZF, Zhang KQ, Niu XM. Novel Polyketide-Terpenoid Hybrid Metabolites and Increased Fungal Nematocidal Ability by Disruption of Genes 277 and 279 in Nematode-Trapping Fungus Arthrobotrys oligospora. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:7870-7879. [PMID: 32525670 DOI: 10.1021/acs.jafc.0c01720] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Nematode-trapping fungus Arthrobotrys oligospora can produce a type of sesquiterpenyl epoxy-cyclohexenoid (SEC) metabolites that are regarded as characteristic chemtaxonomic markers. Here, we reported investigation on the functions of a putatively cupin-like family gene 277 and a dehydrogenase gene 279 by gene engineering, chemical metabolite profiling and phenotype analysis. Ten targeted metabolites were isolated from two mutants Δ277 and Δ279 and four novel metabolites including three polyketide-terpenoid (PK-TP) hybrid ones were characterized. Metabolite C277-1 from mutant Δ277 shared the characteristic feature of the first and simplest PK-TP hybrid precursor, prenyl toluquinol, and metabolites C279-1 and C279-2 from mutant Δ279 shared the basic carbon skeleton of the key PK-TP hybrid precursor, farnesyl toluquinol, for biosynthesis of SEC metabolites. These results suggested that gene 277 should be involved in biosynthesis of the second prenyl unit for farnesyl toluquinol precursor, and gene 279 might be responsible for the diagnostic epoxy formation. Further analysis revealed that genes 277 and 279 might play roles in fungal conidiation, predatory trap formation, and nematode-capturing ability.
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Affiliation(s)
- Yong-Hong Chen
- State Key Laboratory for Conservation and Utilization of Bio-Resources and Key Laboratory for Microbial Resources of the Ministry of Education, School of life Sciences, Yunnan University, Kunming 650091, People's Republic of China
| | - Xiao Liu
- State Key Laboratory for Conservation and Utilization of Bio-Resources and Key Laboratory for Microbial Resources of the Ministry of Education, School of life Sciences, Yunnan University, Kunming 650091, People's Republic of China
| | - Rong Dai
- State Key Laboratory for Conservation and Utilization of Bio-Resources and Key Laboratory for Microbial Resources of the Ministry of Education, School of life Sciences, Yunnan University, Kunming 650091, People's Republic of China
| | - Xia Ou
- State Key Laboratory for Conservation and Utilization of Bio-Resources and Key Laboratory for Microbial Resources of the Ministry of Education, School of life Sciences, Yunnan University, Kunming 650091, People's Republic of China
| | - Zi-Fei Xu
- State Key Laboratory for Conservation and Utilization of Bio-Resources and Key Laboratory for Microbial Resources of the Ministry of Education, School of life Sciences, Yunnan University, Kunming 650091, People's Republic of China
| | - Ke-Qin Zhang
- State Key Laboratory for Conservation and Utilization of Bio-Resources and Key Laboratory for Microbial Resources of the Ministry of Education, School of life Sciences, Yunnan University, Kunming 650091, People's Republic of China
| | - Xue-Mei Niu
- State Key Laboratory for Conservation and Utilization of Bio-Resources and Key Laboratory for Microbial Resources of the Ministry of Education, School of life Sciences, Yunnan University, Kunming 650091, People's Republic of China
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15
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He ZQ, Tan JL, Li N, Zhang HX, Chen YH, Wang LJ, Zhang KQ, Niu XM. Sesquiterpenyl Epoxy-Cyclohexenoids and their Signaling Functions in Nematode-Trapping Fungus Arthrobotrys oligospora. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:13061-13072. [PMID: 31738551 DOI: 10.1021/acs.jafc.9b04968] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In this study, we purified three new sesquiterpenyl epoxy-cyclohexenoid (SEC) analogues, arthrobotrisin D (11) and its two derivatives, from nematode-trapping fungus Arthrobotrys oligospora. Our results revealed that arthrobotrisin type SEC metabolites could be detected in all the test fungal strains from geographically distinct regions grown on different nutrient media, indicative of unique diagnostic character as chemical indicators for A. oligospora. The time course designs over short-term intervals of the fungus under direct contact and indirect contact with living or dead nematodes revealed that arthrobotrisin B and D (6 and 11) displayed significant relationships (positive or negative correlation) with fungal saprophytic and pathogenic stages during a nematode predation event. Interestingly, fungus on nutrient-limiting medium conducive to fungal trap formation could rapidly drop the concentration levels of arthrobotrisins B and D within 6 h when dead nematodes were around, in great contrast to that for living nematodes. Moreover, only in the fungal strain under direct contact with living dominant soil bacteria, arthrobotrisins B and D exhibited significant increase in amounts. Among them, the new SEC, arthrobotrisin D (11) was found to be a key unique metabolic signal for fungal colony growth and fungal interaction with prey and bacteria. Our study suggested that chemical analysis of SEC metabolites in A. oligospora provides a window into the fungal growth status and much valuable information about ecological environments associated with the nematode infections.
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Affiliation(s)
- Zhi-Qiang He
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences , Yunnan University , Kunming 650091 , People's Republic of China
| | - Jian-Lin Tan
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences , Yunnan University , Kunming 650091 , People's Republic of China
- Yunnan Institute of Product Quality Supervision and Inspection & National Tropical Agricultural and Sideline Products Quality Supervision and Inspection Center , Kunming 650223 , People's Republic of China
| | - Nan Li
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences , Yunnan University , Kunming 650091 , People's Republic of China
| | - Hui-Xiang Zhang
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences , Yunnan University , Kunming 650091 , People's Republic of China
| | - Yong-Hong Chen
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences , Yunnan University , Kunming 650091 , People's Republic of China
| | - Li-Jun Wang
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences , Yunnan University , Kunming 650091 , People's Republic of China
| | - Ke-Qin Zhang
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences , Yunnan University , Kunming 650091 , People's Republic of China
| | - Xue-Mei Niu
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences , Yunnan University , Kunming 650091 , People's Republic of China
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Chen YH, He JB, Bai X, Li XN, Lu LF, Liu YC, Zhang KQ, Li SH, Niu XM. Unexpected Biosynthesis of Fluorescein-Like Arthrocolins against Resistant Strains in an Engineered Escherichia coli. Org Lett 2019; 21:6499-6503. [PMID: 31343888 DOI: 10.1021/acs.orglett.9b02371] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Here we provide an unprecedented biofactory where fluorescent dye-like complex xanthenes could be produced in an engineered Escherichia coli. Feeding the strain with toluquinol or hydroquinones resulted in production of novel "unnatural" natural products including four arthrocolins embedded with indolyltriphenyl quaternary carbons. Arthrocolins A-C potently inhibited various human cancer cell lines including paclitaxel-resistant cell line A549/Taxol and methicillin-resistant Staphylococcus aureus and immensely restored the sensitivity of intractable fluconazole-resistant human pathogen Candida albicans to fluconazole.
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Affiliation(s)
- Yong-Hong Chen
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences , Yunnan University , Kunming 650091 , P.R. China
| | - Jiang-Bo He
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences , Yunnan University , Kunming 650091 , P.R. China.,Kunming Key Laboratory of Respiratory Disease , Kunming University , Kunming 650214 , P. R. China
| | - Xue Bai
- State Key Laboratory of Phytochemistry and Plant Resources in West China , Kunming Institute of Botany, Chinese Academy of Sciences , Kunming 650201 , P.R. China
| | - Xiao-Nian Li
- State Key Laboratory of Phytochemistry and Plant Resources in West China , Kunming Institute of Botany, Chinese Academy of Sciences , Kunming 650201 , P.R. China
| | - Lan-Feng Lu
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences , Yunnan University , Kunming 650091 , P.R. China
| | - Yan-Chun Liu
- State Key Laboratory of Phytochemistry and Plant Resources in West China , Kunming Institute of Botany, Chinese Academy of Sciences , Kunming 650201 , P.R. China
| | - Ke-Qin Zhang
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences , Yunnan University , Kunming 650091 , P.R. China
| | - Sheng-Hong Li
- State Key Laboratory of Phytochemistry and Plant Resources in West China , Kunming Institute of Botany, Chinese Academy of Sciences , Kunming 650201 , P.R. China
| | - Xue-Mei Niu
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences , Yunnan University , Kunming 650091 , P.R. China
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17
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Youssar L, Wernet V, Hensel N, Yu X, Hildebrand HG, Schreckenberger B, Kriegler M, Hetzer B, Frankino P, Dillin A, Fischer R. Intercellular communication is required for trap formation in the nematode-trapping fungus Duddingtonia flagrans. PLoS Genet 2019; 15:e1008029. [PMID: 30917129 PMCID: PMC6453484 DOI: 10.1371/journal.pgen.1008029] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 04/08/2019] [Accepted: 02/18/2019] [Indexed: 11/21/2022] Open
Abstract
Nematode-trapping fungi (NTF) are a large and diverse group of fungi, which may switch from a saprotrophic to a predatory lifestyle if nematodes are present. Different fungi have developed different trapping devices, ranging from adhesive cells to constricting rings. After trapping, fungal hyphae penetrate the worm, secrete lytic enzymes and form a hyphal network inside the body. We sequenced the genome of Duddingtonia flagrans, a biotechnologically important NTF used to control nematode populations in fields. The 36.64 Mb genome encodes 9,927 putative proteins, among which are more than 638 predicted secreted proteins. Most secreted proteins are lytic enzymes, but more than 200 were classified as small secreted proteins (< 300 amino acids). 117 putative effector proteins were predicted, suggesting interkingdom communication during the colonization. As a first step to analyze the function of such proteins or other phenomena at the molecular level, we developed a transformation system, established the fluorescent proteins GFP and mCherry, adapted an assay to monitor protein secretion, and established gene-deletion protocols using homologous recombination or CRISPR/Cas9. One putative virulence effector protein, PefB, was transcriptionally induced during the interaction. We show that the mature protein is able to be imported into nuclei in Caenorhabditis elegans cells. In addition, we studied trap formation and show that cell-to-cell communication is required for ring closure. The availability of the genome sequence and the establishment of many molecular tools will open new avenues to studying this biotechnologically relevant nematode-trapping fungus. Nematode-trapping fungi are fascinating microorganisms, because they are able to switch from saprotrophic growth to a predatory lifestyle. Duddingtonia flagrans forms adhesive trap systems and conidia and resistant chlamydospores. Chlamydospores are ideal for dissemination in the environment to control nematode populations in the field. We show that D. flagrans is able to catch C. elegans but also the very large wine-pathogenic nematode Xiphinema index. We sequenced the D. flagrans genome and show that it encodes about 10,000 genes with a large proportion of secreted proteins. We hypothesize that virulence effector proteins are involved in the interkingdom organismic interaction and identified more than 100 candidates. In order to investigate the molecular biology of D. flagrans and its interaction with nematodes, we established a transformation system and several molecular tools. We show that cell-to-cell communication and hyphal fusion are required for trap formation. Finally, we show that one putative virulence effector protein targets nuclei when expressed in C. elegans.
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Affiliation(s)
- Loubna Youssar
- Department of Microbiology, Karlsruhe Institute of Technology (KIT)—South Campus, Institute for Applied Biosciences, Karlsruhe, Germany
| | - Valentin Wernet
- Department of Microbiology, Karlsruhe Institute of Technology (KIT)—South Campus, Institute for Applied Biosciences, Karlsruhe, Germany
| | - Nicole Hensel
- Department of Microbiology, Karlsruhe Institute of Technology (KIT)—South Campus, Institute for Applied Biosciences, Karlsruhe, Germany
| | - Xi Yu
- Department of Microbiology, Karlsruhe Institute of Technology (KIT)—South Campus, Institute for Applied Biosciences, Karlsruhe, Germany
| | - Heinz-Georg Hildebrand
- Department of Microbiology, Karlsruhe Institute of Technology (KIT)—South Campus, Institute for Applied Biosciences, Karlsruhe, Germany
| | - Birgit Schreckenberger
- Department of Microbiology, Karlsruhe Institute of Technology (KIT)—South Campus, Institute for Applied Biosciences, Karlsruhe, Germany
| | - Marius Kriegler
- Department of Microbiology, Karlsruhe Institute of Technology (KIT)—South Campus, Institute for Applied Biosciences, Karlsruhe, Germany
| | | | - Phillip Frankino
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of Berkeley, Berkeley, California, United States of America
| | - Andrew Dillin
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of Berkeley, Berkeley, California, United States of America
| | - Reinhard Fischer
- Department of Microbiology, Karlsruhe Institute of Technology (KIT)—South Campus, Institute for Applied Biosciences, Karlsruhe, Germany
- * E-mail:
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18
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Liang LM, Zou CG, Xu J, Zhang KQ. Signal pathways involved in microbe-nematode interactions provide new insights into the biocontrol of plant-parasitic nematodes. Philos Trans R Soc Lond B Biol Sci 2019; 374:20180317. [PMID: 30967028 PMCID: PMC6367146 DOI: 10.1098/rstb.2018.0317] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/25/2018] [Indexed: 11/12/2022] Open
Abstract
Plant-parasitic nematodes (PPNs) cause severe damage to agricultural crops worldwide. As most chemical nematicides have negative environmental side effects, there is a pressing need for developing efficient biocontrol methods. Nematophagous microbes, the natural enemies of nematodes, are potential biocontrol agents against PPNs. These natural enemies include both bacteria and fungi and they use diverse methods to infect and kill nematodes. For instance, nematode-trapping fungi can sense host signals and produce special trapping devices to capture nematodes, whereas endo-parasitic fungi can kill nematodes by spore adhesion and invasive growth to break the nematode cuticle. By contrast, nematophagous bacteria can secrete virulence factors to kill nematodes. In addition, some bacteria can mobilize nematode-trapping fungi to kill nematodes. In response, nematodes can also sense and defend against the microbial pathogens using strategies such as producing anti-microbial peptides regulated by the innate immunity system. Recent progresses in our understanding of the signal pathways involved in microbe-nematode interactions are providing new insights in developing efficient biological control strategies against PPNs. This article is part of the theme issue 'Biotic signalling sheds light on smart pest management'.
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Affiliation(s)
- Lian-Ming Liang
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan and The Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan University, Kunming 650091, People's Republic of China
- School of Life Science, Yunnan University, Kunming 650091, People's Republic of China
| | - Cheng-Gang Zou
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan and The Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan University, Kunming 650091, People's Republic of China
- School of Life Science, Yunnan University, Kunming 650091, People's Republic of China
| | - Jianping Xu
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan and The Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan University, Kunming 650091, People's Republic of China
- Department of Biology, McMaster University, Hamilton, Ontario, CanadaL8S 4K1
| | - Ke-Qin Zhang
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan and The Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan University, Kunming 650091, People's Republic of China
- School of Life Science, Yunnan University, Kunming 650091, People's Republic of China
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19
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Li C, Lo I, Hsueh Y, Chung Y, Wang S, Korinek M, Tsai Y, Cheng Y, Hwang T, Wang CCC, Chang F, Wu Y. Epigenetic Manipulation Induces the Production of Coumarin‐Type Secondary Metabolite from
Arthrobotrys foliicola. Isr J Chem 2019. [DOI: 10.1002/ijch.201800162] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Chi‐Ying Li
- Graduate Institute of Natural ProductsCollege of Pharmacy Kaohsiung Medical University Kaohsiung 807 Taiwan
- Department of Pharmacology and Pharmaceutical Sciences University of Southern CaliforniaSchool of Pharmacy Los Angeles CA 90089 USA
| | - I‐Wen Lo
- Graduate Institute of Natural ProductsCollege of Pharmacy Kaohsiung Medical University Kaohsiung 807 Taiwan
| | - Yen‐Ping Hsueh
- Institute of Molecular BiologyAcademia Sinica Taipei 11529 Taiwan
| | - Yu‐Ming Chung
- Graduate Institute of Natural ProductsCollege of Pharmacy Kaohsiung Medical University Kaohsiung 807 Taiwan
| | - Shih‐Wei Wang
- Graduate Institute of Natural ProductsCollege of Pharmacy Kaohsiung Medical University Kaohsiung 807 Taiwan
- Department of MedicineMackay Medical College New Taipei City 252 Taiwan
| | - Michal Korinek
- Graduate Institute of Natural ProductsCollege of Pharmacy Kaohsiung Medical University Kaohsiung 807 Taiwan
- Graduate Institute of Natural Products, College of Medicine, and Chinese Herbal Medicine Research Team, Healthy Aging Research CenterChang Gung University Taoyuan 33302 Taiwan
- Research Center for Chinese Herbal Medicine, Research Center for Food and Cosmetic Safety, and Graduate Institute of Health Industry Technology, College of Human EcologyChang Gung University of Science and Technology Taoyuan 33302 Taiwan
| | - Yi‐Hong Tsai
- Graduate Institute of Natural ProductsCollege of Pharmacy Kaohsiung Medical University Kaohsiung 807 Taiwan
| | - Yuan‐Bin Cheng
- Graduate Institute of Natural ProductsCollege of Pharmacy Kaohsiung Medical University Kaohsiung 807 Taiwan
- Department of Medical ResearchKaohsiung Medical University Kaohsiung 807 Taiwan
| | - Tsong‐Long Hwang
- Graduate Institute of Natural Products, College of Medicine, and Chinese Herbal Medicine Research Team, Healthy Aging Research CenterChang Gung University Taoyuan 33302 Taiwan
- Research Center for Chinese Herbal Medicine, Research Center for Food and Cosmetic Safety, and Graduate Institute of Health Industry Technology, College of Human EcologyChang Gung University of Science and Technology Taoyuan 33302 Taiwan
- Department of AnesthesiologyChang Gung Memorial Hospital Taoyuan 33305 Taiwan
| | - Clay C. C. Wang
- Department of Pharmacology and Pharmaceutical Sciences University of Southern CaliforniaSchool of Pharmacy Los Angeles CA 90089 USA
- Department of Chemistry, University of Southern CaliforniaCollege of Letters, Arts, and Sciences Los Angeles CA 90089 USA
| | - Fang‐Rong Chang
- Graduate Institute of Natural ProductsCollege of Pharmacy Kaohsiung Medical University Kaohsiung 807 Taiwan
- National Research Institute of Chinese Medicine Taipei 112 Taiwan
| | - Yang‐Chang Wu
- Graduate Institute of Natural ProductsCollege of Pharmacy Kaohsiung Medical University Kaohsiung 807 Taiwan
- Department of Medical ResearchKaohsiung Medical University Kaohsiung 807 Taiwan
- Research Center for Natural Products & Drug DevelopmentKaohsiung Medical University Kaohsiung 807 Taiwan
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20
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Integrated Metabolomics and Morphogenesis Reveal Volatile Signaling of the Nematode-Trapping Fungus Arthrobotrys oligospora. Appl Environ Microbiol 2018; 84:AEM.02749-17. [PMID: 29453265 PMCID: PMC5930339 DOI: 10.1128/aem.02749-17] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 02/12/2018] [Indexed: 12/01/2022] Open
Abstract
The adjustment of metabolic patterns is fundamental to fungal biology and plays vital roles in adaptation to diverse ecological challenges. Nematode-trapping fungi can switch their lifestyle from saprophytic to pathogenic by developing specific trapping devices induced by nematodes to infect their prey as a response to nutrient depletion in nature. However, the chemical identity of the specific fungal metabolites used during the switch remains poorly understood. We hypothesized that these important signal molecules might be volatile in nature. Gas chromatography-mass spectrometry was used to carry out comparative analysis of fungal metabolomics during the saprophytic and pathogenic lifestyles of the model species Arthrobotrys oligospora. Two media commonly used in research on this species, cornmeal agar (CMA) and potato dextrose agar (PDA), were chosen for use in this study. The fungus produced a small group of volatile furanone and pyrone metabolites that were associated with the switch from the saprophytic to the pathogenic stage. A. oligospora fungi grown on CMA tended to produce more traps and employ attractive furanones to improve the utilization of traps, while fungi grown on PDA developed fewer traps and used nematode-toxic furanone metabolites to compensate for insufficient traps. Another volatile pyrone metabolite, maltol, was identified as a morphological regulator for enhancing trap formation. Deletion of the gene AOL_s00079g496 in A. oligospora led to increased amounts of the furanone attractant (2-fold) in mutants and enhanced the attractive activity (1.5-fold) of the fungus, while it resulted in decreased trap formation. This investigation provides new insights regarding the comprehensive tactics of fungal adaptation to environmental stress, integrating both morphological and metabolomic mechanisms. IMPORTANCE Nematode-trapping fungi are a unique group of soil-living fungi that can switch from the saprophytic to the pathogenic lifestyle once they come into contact with nematodes as a response to nutrient depletion. In this study, we investigated the metabolic response during the switch and the key types of metabolites involved in the interaction between fungi and nematodes. Our findings indicate that A. oligospora develops multiple and flexible metabolic tactics corresponding to different morphological responses to nematodes. A. oligospora can use similar volatile furanone and pyrone metabolites with different ecological functions to help capture nematodes in the fungal switch from the saprophytic to the pathogenic lifestyle. Furthermore, studies with A. oligospora mutants with increased furanone and pyrone metabolites confirmed the results. This investigation reveals the importance of volatile signaling in the comprehensive tactics used by nematode-trapping fungi, integrating both morphological and metabolomic mechanisms.
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Predator-prey interactions of nematode-trapping fungi and nematodes: both sides of the coin. Appl Microbiol Biotechnol 2018. [PMID: 29523933 DOI: 10.1007/s00253-018-8897-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Nematode-trapping fungi develop complex trapping devices to capture and consume nematodes. The dynamics of these organisms is especially important given the pathogenicity of nematodes and, consequently, the potential application of nematode-trapping fungi as biocontrol agents. Furthermore, both the nematodes and nematode-trapping fungi can be easily grown in laboratories, making them a unique manipulatable predator-prey system to study their coevolution. Several different aspects of these fungi have been studied, such as their genetics and the different factors triggering trap formation. In this review, we use the nematode-trapping fungus Arthrobotrys oligospora (which forms adhesive nets) as a model to describe the trapping process. We divide this process into several stages; namely attraction, recognition, trap formation, adhesion, penetration, and digestion. We summarize the latest findings in the field and current knowledge on the interactions between nematodes and nematode-trapping fungi, representing both sides of the predator-prey interaction.
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Teng LL, Song TY, Xu ZF, Liu X, Dai R, Chen YH, Li SH, Zhang KQ, Niu XM. Selected Mutations Revealed Intermediates and Key Precursors in the Biosynthesis of Polyketide-Terpenoid Hybrid Sesquiterpenyl Epoxy-cyclohexenoids. Org Lett 2017; 19:3923-3926. [PMID: 28692300 DOI: 10.1021/acs.orglett.7b01846] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Sesquiterpenyl epoxy-cyclohexenoids (SECs) show impressive biological activities. However, the key pathways for SECs still remain unambiguous. Unexpectedly, 11 new SECs and derivatives with diverse oxidation patterns were isolated after the deletion of gene 274. A high accumulation of toluquinol and its new glycosides in mutant Δ276 and further isolation of the most crucial precursors farnesyl hydroquinone, farnesyl quinone, and three new derivatives from mutant Δ278 confirm that farnesylation at toluquinol is the key step for SECs.
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Affiliation(s)
- Lin-Lin Teng
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University , Kunming 650091, P. R. China.,State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences , Kunming 650204, P. R. China
| | - Tian-Yang Song
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University , Kunming 650091, P. R. China
| | - Zi-Fei Xu
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University , Kunming 650091, P. R. China
| | - Xiao Liu
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University , Kunming 650091, P. R. China
| | - Rong Dai
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University , Kunming 650091, P. R. China
| | - Yong-Hong Chen
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University , Kunming 650091, P. R. China
| | - Sheng-Hong Li
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences , Kunming 650204, P. R. China
| | - Ke-Qin Zhang
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University , Kunming 650091, P. R. China
| | - Xue-Mei Niu
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Sciences, Yunnan University , Kunming 650091, P. R. China
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Song TY, Xu ZF, Chen YH, Ding QY, Sun YR, Miao Y, Zhang KQ, Niu XM. Potent Nematicidal Activity and New Hybrid Metabolite Production by Disruption of a Cytochrome P450 Gene Involved in the Biosynthesis of Morphological Regulatory Arthrosporols in Nematode-Trapping Fungus Arthrobotrys oligospora. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2017; 65:4111-4120. [PMID: 28475838 DOI: 10.1021/acs.jafc.7b01290] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Types of polyketide synthase-terpenoid synthase (PKS-TPS) hybrid metabolites, including arthrosporols with significant morphological regulatory activity, have been elucidated from nematode-trapping fungus Arthrobotrys oligospora. A previous study suggested that the gene cluster AOL_s00215 in A. oligospora was involved in the production of arthrosporols. Here, we report that disruption of one cytochrome P450 monooxygenase gene AOL_s00215g280 in the cluster resulted in significant phenotypic difference and much aerial hyphae. A further bioassay indicated that the mutant showed a dramatic decrease in the conidial formation but developed numerous traps and killed 85% nematodes within 6 h in contact with prey, in sharp contrast to the wild-type strain with no obvious response. Chemical investigation revealed huge accumulation of three new PKS-TPS epoxycyclohexone derivatives with different oxygenated patterns around the epoxycyclohexone moiety and the absence of arthrosporols in the cultural broth of the mutant ΔAOL_s00215g280. These findings suggested that a study on the biosynthetic pathway for morphological regulatory metabolites in nematode-trapping fungus would provide an efficient way to develop new fungal biocontrol agents.
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Affiliation(s)
- Tian-Yang Song
- State Key Laboratory for Conservation and Utilization of Bio-Resources and Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Science, Yunnan University , Kunming, Yunnan 650091, People's Republic of China
| | - Zi-Fei Xu
- State Key Laboratory for Conservation and Utilization of Bio-Resources and Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Science, Yunnan University , Kunming, Yunnan 650091, People's Republic of China
| | - Yong-Hong Chen
- State Key Laboratory for Conservation and Utilization of Bio-Resources and Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Science, Yunnan University , Kunming, Yunnan 650091, People's Republic of China
| | - Qiu-Yan Ding
- State Key Laboratory for Conservation and Utilization of Bio-Resources and Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Science, Yunnan University , Kunming, Yunnan 650091, People's Republic of China
| | - Yu-Rong Sun
- State Key Laboratory for Conservation and Utilization of Bio-Resources and Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Science, Yunnan University , Kunming, Yunnan 650091, People's Republic of China
| | - Yang Miao
- State Key Laboratory for Conservation and Utilization of Bio-Resources and Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Science, Yunnan University , Kunming, Yunnan 650091, People's Republic of China
| | - Ke-Qin Zhang
- State Key Laboratory for Conservation and Utilization of Bio-Resources and Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Science, Yunnan University , Kunming, Yunnan 650091, People's Republic of China
| | - Xue-Mei Niu
- State Key Laboratory for Conservation and Utilization of Bio-Resources and Key Laboratory for Microbial Resources of the Ministry of Education, School of Life Science, Yunnan University , Kunming, Yunnan 650091, People's Republic of China
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Xu ZF, Chen YH, Song TY, Zeng ZJ, Yan N, Zhang KQ, Niu XM. Nematicidal Key Precursors for the Biosynthesis of Morphological Regulatory Arthrosporols in the Nematode-Trapping Fungus Arthrobotrys oligospora. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2016; 64:7949-7956. [PMID: 27723963 DOI: 10.1021/acs.jafc.6b03241] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Arthrobotrys oligospora is the first recognized nematode-trapping fungus and by far the most abundant in the environment. Our recent study revealed the polyketide synthase (PKS) gene AOL_s00215g283 in A. oligospora involved in the production of many secondary metabolites and the trap formation of the fungus. Here we report that the disruption of two genes in the upstream flanking region of the gene AOL_s00215g283, AOL_s00215g281 and AOL_s00215g282, which putatively encoded one amidohydrolase and one cytochrome P450 monooxygenase, respectively, both resulted in significant nematicidal activity of the cultural broths of the mutants and loss of morphological regulatory arthrosporols. Chemical investigation revealed the huge accumulation of 6-methylsalicylic acid in the cultural broth of the mutant ΔAOL_s00215g281 and the high production of m-cresol in the mutant ΔAOL_s00215g282, respectively. Further bioassay revealed that 6-methylsalicylic acid and m-cresol displayed significant nematicidal activity toward root-knot nematodes Meloidogyne incognita with IC90 values of 300 and 100 μg/mL, respectively. The mutant ΔAOL_s00215g282 displayed a more complex metabolite profile than the mutant ΔAOL_s00215g281, suggesting that m-cresol was a more versatile key precursor than 6-methylsalicylic acid. These findings not only demonstrated that the gene AOL_s00215g283 encodes the 6-methylsalicylic acid synthase and the gene AOL_s00215g281 encodes the decarboxylase for 6-methylsalicylic acid but also provided evidence for the potential functions of the precursors in fungal complex biosynthetic pathways and had more implications for the establishment of efficient fungal biocontrol agents.
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Affiliation(s)
- Zi-Fei Xu
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University , Kunming 650091, People's Republic of China
| | - Yong-Hong Chen
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University , Kunming 650091, People's Republic of China
| | - Tian-Yang Song
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University , Kunming 650091, People's Republic of China
| | - Zhi-Jun Zeng
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University , Kunming 650091, People's Republic of China
| | - Ni Yan
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University , Kunming 650091, People's Republic of China
| | - Ke-Qin Zhang
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University , Kunming 650091, People's Republic of China
| | - Xue-Mei Niu
- State Key Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University , Kunming 650091, People's Republic of China
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Degenkolb T, Vilcinskas A. Metabolites from nematophagous fungi and nematicidal natural products from fungi as an alternative for biological control. Part I: metabolites from nematophagous ascomycetes. Appl Microbiol Biotechnol 2015; 100:3799-812. [PMID: 26715220 PMCID: PMC4824826 DOI: 10.1007/s00253-015-7233-6] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2015] [Revised: 11/29/2015] [Accepted: 12/02/2015] [Indexed: 11/29/2022]
Abstract
Plant-parasitic nematodes are estimated to cause global annual losses of more than US$ 100 billion. The number of registered nematicides has declined substantially over the last 25 years due to concerns about their non-specific mechanisms of action and hence their potential toxicity and likelihood to cause environmental damage. Environmentally beneficial and inexpensive alternatives to chemicals, which do not affect vertebrates, crops, and other non-target organisms, are therefore urgently required. Nematophagous fungi are natural antagonists of nematode parasites, and these offer an ecophysiological source of novel biocontrol strategies. In this first section of a two-part review article, we discuss 83 nematicidal and non-nematicidal primary and secondary metabolites found in nematophagous ascomycetes. Some of these substances exhibit nematicidal activities, namely oligosporon, 4',5'-dihydrooligosporon, talathermophilins A and B, phomalactone, aurovertins D and F, paeciloxazine, a pyridine carboxylic acid derivative, and leucinostatins. Blumenol A acts as a nematode attractant. Other substances, such as arthrosporols and paganins, play a decisive role in the life cycle of the producers, regulating the formation of reproductive or trapping organs. We conclude by considering the potential applications of these beneficial organisms in plant protection strategies.
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Affiliation(s)
- Thomas Degenkolb
- Institute for Insect Biotechnology, Justus-Liebig-University of Giessen, Heinrich-Buff-Ring 26-32, 35392, Giessen, Germany
| | - Andreas Vilcinskas
- Institute for Insect Biotechnology, Justus-Liebig-University of Giessen, Heinrich-Buff-Ring 26-32, 35392, Giessen, Germany. .,Department of Bioresources, Fraunhofer Institute for Molecular Biology and Applied Ecology, Winchester Strasse 2, 35394, Giessen, Germany.
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