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Li J, Wei X, Pei Z, Sun J, Xi J, Li X, Shapiro-IIan D, Ruan W. Volatile organic compounds released from entomopathogenic nematode-infected insect cadavers for the biocontrol of Meloidogyne incognita. PEST MANAGEMENT SCIENCE 2024. [PMID: 38943354 DOI: 10.1002/ps.8268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2024] [Revised: 05/29/2024] [Accepted: 06/10/2024] [Indexed: 07/01/2024]
Abstract
BACKGROUND Root-knot nematodes (RKNs), Meloidogyne spp., are one of the most destructive polyphagous plant-parasitic nematodes. They pose a serious threat to global food security and are difficult to control. Entomopathogenic nematodes (EPNs) show promise in controlling RKNs. However, it remains unclear whether the volatile organic compounds (VOCs) emitted from EPN-infected cadavers can control RKNs. RESULTS We investigated the fumigation activity of VOCs released from cadavers infected by five different species of EPNs on RKNs in Petri dishes, and found that VOCs released from Steinernema feltiae (SN strain) and S. carpocapsae (All strain) infected cadavers had a significant lethal effect on second-stage juveniles (J2s) of Meloidogyne incognita. The VOCs released from the cadavers infected with S. feltiae were analyzed using SPME-GC/MS. Dimethyl disulfide (DMDS), tetradecane, pentadecane, and butylated hydroxytoluene (BHT), were selected for a validation experiment with pure compounds. The DMDS compound had significant nematicidal activity and repelled J2s. DMDS also inhibited egg hatching and the invasion of tomato roots by J2s. In a pot experiment, the addition of S. feltiae-infected cadavers and cadavers wrapped with a 400-mesh nylon net also significantly reduced the population of RKNs in tomato roots after 7 days. The number of root knots and eggs was reduced by 58% and 74.34%, respectively, compared to the control. CONCLUSION These results suggested that the VOCs emitted by the EPN-infected cadavers affected various developmental stages of M. incognita and thus have the potential to be used in controlling RKNs through multiple methods. © 2024 Society of Chemical Industry.
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Affiliation(s)
- Jingjing Li
- College of Life Sciences, Nankai University, Tianjin, China
- Suzhou Academy of Agricultural Sciences, Institute of Agricultural Sciences in Taihu Lake Region of Jiangsu, Suzhou, China
| | - Xianqin Wei
- College of Life Sciences, Nankai University, Tianjin, China
| | - Zixuan Pei
- College of Life Sciences, Nankai University, Tianjin, China
| | - Jie Sun
- College of Life Sciences, Nankai University, Tianjin, China
| | - Jiale Xi
- College of Life Sciences, Nankai University, Tianjin, China
| | - Xingyue Li
- Institute of Plant Protection, Sichuan Academy of Agricultural Sciences, Chengdu, China
| | | | - Weibin Ruan
- College of Life Sciences, Nankai University, Tianjin, China
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Long Q, Zhou W, Zhou H, Tang Y, Chen W, Liu Q, Bian X. Polyamine-containing natural products: structure, bioactivity, and biosynthesis. Nat Prod Rep 2024; 41:525-564. [PMID: 37873660 DOI: 10.1039/d2np00087c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
Covering: 2005 to August, 2023Polyamine-containing natural products (NPs) have been isolated from a wide range of terrestrial and marine organisms and most of them exhibit remarkable and diverse activities, including antimicrobial, antiprotozoal, antiangiogenic, antitumor, antiviral, iron-chelating, anti-depressive, anti-inflammatory, insecticidal, antiobesity, and antioxidant properties. Their extraordinary activities and potential applications in human health and agriculture attract increasing numbers of studies on polyamine-containing NPs. In this review, we summarized the source, structure, classification, bioactivities and biosynthesis of polyamine-containing NPs, focusing on the biosynthetic mechanism of polyamine itself and representative polyamine alkaloids, polyamine-containing siderophores with catechol/hydroxamate/hydroxycarboxylate groups, nonribosomal peptide-(polyketide)-polyamine (NRP-(PK)-PA), and NRP-PK-long chain poly-fatty amine (lcPFAN) hybrid molecules.
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Affiliation(s)
- Qingshan Long
- Hunan Provincial Engineering and Technology Research Center for Agricultural Microbiology Application, Hunan Institute of Microbiology, Changsha, 410009, China.
| | - Wen Zhou
- Key Laboratory of Veterinary Chemical Drugs and Pharmaceutics, Ministry of Agriculture and Rural, Affairs, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Haibo Zhou
- Helmholtz International Lab for Anti-Infectives, Shandong University-Helmholtz Institute of Biotechnology, State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, China.
| | - Ying Tang
- Hunan Provincial Engineering and Technology Research Center for Agricultural Microbiology Application, Hunan Institute of Microbiology, Changsha, 410009, China.
| | - Wu Chen
- College of Plant Protection, Hunan Agricultural University, Changsha, 410128, China.
| | - Qingshu Liu
- Hunan Provincial Engineering and Technology Research Center for Agricultural Microbiology Application, Hunan Institute of Microbiology, Changsha, 410009, China.
| | - Xiaoying Bian
- Helmholtz International Lab for Anti-Infectives, Shandong University-Helmholtz Institute of Biotechnology, State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, China.
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Touray M, Ulug D, Gulsen SH, Cimen H, Hazir C, Bode HB, Hazir S. Natural products from Xenorhabdus and Photorhabdus show promise as biolarvicides against Aedes albopictus. PEST MANAGEMENT SCIENCE 2024. [PMID: 38619291 DOI: 10.1002/ps.8127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 04/04/2024] [Accepted: 04/10/2024] [Indexed: 04/16/2024]
Abstract
BACKGROUND In the perpetual struggle to manage mosquito populations, there has been increasing demand for the development of biopesticides to supplant/complement current products. The insecticidal potential of Xenorhabdus and Photorhabdus has long been recognized and is of interest for the control of important mosquitoes like Aedes albopictus which vectors over 20 different arboviruses of global public health concern. RESULTS The larvicidal effects of cell-free supernatants, cell growth cultures and cell mass of an extensive list of Xenorhabdus and Photorhabdus spp. was investigated. They were quite effective against Ae. albopictus causing larval mortality ranging between 52-100%. Three Photorhabdus spp. and 13 Xenorhabdus spp. release larvicidal compounds in cell-free supernatants. Cell growth culture of all tested species exhibited larvicidal activity, except for Xenorhabdus sp. TS4. Twenty-one Xenorhabdus and Photorhabdus bacterial cells (pellet) exhibited oral toxicity (59-91%) against exposed larvae. The effect of bacterial supernatants on the mosquito eggs were also assessed. Bacterial supernatants inhibited the hatching of mosquito eggs; when unhatched eggs were transferred to clean water, they all hatched. Using the easyPACId approach, the larvicidal compounds in bacterial supernatant were identified as fabclavine from X. szentirmaii and xencoumacin from X. nematophila (causing 98 and 70% mortality, respectively, after 48 h). Xenorhabdus cabanillasii and X. hominickii fabclavines were as effective as commercial Bacillus thuringiensis subsp. israelensis and spinosad products within 5 days post-application (dpa). CONCLUSION Fabclavine and xenocoumacin can be developed into novel biolarvicides, can be used as a model to synthesize other compounds or/and can be combined with other commercial biolarvicides. © 2024 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- Mustapha Touray
- Department of Biology, Faculty of Science, Aydin Adnan Menderes University, Aydın, Turkey
| | - Derya Ulug
- Department of Biology, Faculty of Science, Aydin Adnan Menderes University, Aydın, Turkey
| | - Sebnem Hazal Gulsen
- Department of Biology, Faculty of Science, Aydin Adnan Menderes University, Aydın, Turkey
- Department of Plant and Animal Production, Kocarli Vocational School, Aydin Adnan Menderes University, Aydın, Turkey
| | - Harun Cimen
- Recombinant DNA and Recombinant Protein Center, Aydın Adnan Menderes University, Aydın, Turkey
| | - Canan Hazir
- Aydin Health Services Vocational School, Adnan Menderes University, Aydın, Turkey
| | - Helge B Bode
- Max-Planck-Institute for Terrestrial Microbiology, Department of Natural Products in Organismic Interactions, Marburg, Germany
- Molekulare Biotechnologie, Fachbereich Biowissenschaften, Goethe Universität Frankfurt, Frankfurt, Germany
- Center for Synthetic Microbiology, Phillips University Marburg, Marburg, Germany
- Department of Chemistry, Phillips University Marburg, Marburg, Germany
- Senckenberg Gesellschaft für Naturforschung, Frankfurt am Main, Germany
| | - Selcuk Hazir
- Department of Biology, Faculty of Science, Aydin Adnan Menderes University, Aydın, Turkey
- Department of Biotechnology, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, Chennai, India
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Palma L, Frizzo L, Kaiser S, Berry C, Caballero P, Bode HB, Del Valle EE. Genome Sequence Analysis of Native Xenorhabdus Strains Isolated from Entomopathogenic Nematodes in Argentina. Toxins (Basel) 2024; 16:108. [PMID: 38393187 PMCID: PMC10892061 DOI: 10.3390/toxins16020108] [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: 01/02/2024] [Revised: 02/05/2024] [Accepted: 02/13/2024] [Indexed: 02/25/2024] Open
Abstract
Entomopathogenic nematodes from the genus Steinernema (Nematoda: Steinernematidae) are capable of causing the rapid killing of insect hosts, facilitated by their association with symbiotic Gram-negative bacteria in the genus Xenorhabdus (Enterobacterales: Morganellaceae), positioning them as interesting candidate tools for the control of insect pests. In spite of this, only a limited number of species from this bacterial genus have been identified from their nematode hosts and their insecticidal properties documented. This study aimed to perform the genome sequence analysis of fourteen Xenorhabdus strains that were isolated from Steinernema nematodes in Argentina. All of the strains were found to be able of killing 7th instar larvae of Galleria mellonella (L.) (Lepidoptera: Pyralidae). Their sequenced genomes harbour 110 putative insecticidal proteins including Tc, Txp, Mcf, Pra/Prb and App homologs, plus other virulence factors such as putative nematocidal proteins, chitinases and secondary metabolite gene clusters for the synthesis of different bioactive compounds. Maximum-likelihood phylogenetic analysis plus average nucleotide identity calculations strongly suggested that three strains should be considered novel species. The species name for strains PSL and Reich (same species according to % ANI) is proposed as Xenorhabdus littoralis sp. nov., whereas strain 12 is proposed as Xenorhabdus santafensis sp. nov. In this work, we present a dual insight into the biocidal potential and diversity of the Xenorhabdus genus, demonstrated by different numbers of putative insecticidal genes and biosynthetic gene clusters, along with a fresh exploration of the species within this genus.
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Affiliation(s)
- Leopoldo Palma
- Instituto de Biotecnología y Biomedicina (BIOTECMED), Departamento de Genética, Universitat de València, 46100 Burjassot, Spain
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Ciudad Autónoma de Buenos Aires C1033AAJ, Argentina
- Instituto Multidisciplinario de Investigación y Transferencia Agroalimentaria y Biotecnológica (IMITAB), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Villa María (UNVM), Villa María 1555, Argentina
| | - Laureano Frizzo
- ICIVET Litoral, CONICET-UNL, Departamento de Salud Pública, Facultad de Ciencias Veterinarias, Universidad Nacional del Litoral, Esperanza S3080, Argentina;
| | - Sebastian Kaiser
- Department of Natural Products in Organismic Interactions, Max-Planck-Institute for Terrestrial Microbiology, 35043 Marburg, Germany; (S.K.); (H.B.B.)
- Evolutionary Biochemistry Group, Max-Planck-Institute for Terrestrial Microbiology, 35043 Marburg, Germany
| | - Colin Berry
- Cardiff School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, UK;
| | - Primitivo Caballero
- Institute for Multidisciplinary Research in Applied Biology, Universidad Pública de Navarra, 31006 Pamplona, Spain;
- Departamento de Investigación y Desarrollo, Bioinsectis SL, Polígono Industrial Mocholi Plaza Cein 5, Nave A14, 31110 Noain, Spain
| | - Helge B. Bode
- Department of Natural Products in Organismic Interactions, Max-Planck-Institute for Terrestrial Microbiology, 35043 Marburg, Germany; (S.K.); (H.B.B.)
- Molecular Biotechnology, Department of Biosciences, Goethe Universität Frankfurt, 60438 Frankfurt, Germany
- Center for Synthetic Microbiology (SYNMIKRO), Phillips University Marburg, 35043 Marburg, Germany
- Department of Chemistry, Phillips University Marburg, 35043 Marburg, Germany
- Senckenberg Gesellschaft für Naturforschung, 60325 Frankfurt, Germany
| | - Eleodoro Eduardo Del Valle
- ICiagro Litoral, CONICET, Facultad de Ciencias Agrarias, Universidad Nacional del Litoral, Kreder 2805, Esperanza S3080, Argentina
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Zhang Y, Li H, Wang F, Liu C, Reddy GVP, Li H, Li Z, Sun Y, Zhao Z. Discovery of a new highly pathogenic toxin involved in insect sepsis. Microbiol Spectr 2023; 11:e0142223. [PMID: 37787562 PMCID: PMC10715044 DOI: 10.1128/spectrum.01422-23] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 08/07/2023] [Indexed: 10/04/2023] Open
Abstract
IMPORTANCE As a current biocontrol resource, entomopathogenic nematodes and their symbiotic bacterium can produce many toxin factors to trigger insect sepsis, having the potential to promote sustainable pest management. In this study, we found Steinernema feltiae and Xenorhabdus bovienii were highly virulent against the insects. After infective juvenile injection, Galleria mellonella quickly turned black and softened with increasing esterase activity. Simultaneously, X. bovienii attacked hemocytes and released toxic components, resulting in extensive hemolysis and sepsis. Then, we applied high-resolution mass spectrometry-based metabolomics and found multiple substances were upregulated in the host hemolymph. We found extremely hazardous actinomycin D produced via 3-hydroxyanthranilic acid metabolites. Moreover, a combined transcriptomic analysis revealed that gene expression of proteins associated with actinomycin D was upregulated. Our research revealed actinomycin D might be responsible for the infestation activity of X. bovienii, indicating a new direction for exploring the sepsis mechanism and developing novel biotic pesticides.
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Affiliation(s)
- Yuan Zhang
- MARA Key Laboratory of Surveillance and Management for Plant Quarantine Pests, College of Plant Protection, China Agricultural University, Beijing, China
| | - Hao Li
- MARA Key Laboratory of Surveillance and Management for Plant Quarantine Pests, College of Plant Protection, China Agricultural University, Beijing, China
| | - Fang Wang
- Institute of Plant Protection, Ningxia Academy of Agricultural and Forestry Sciences, Yinchuan, China
| | - Chang Liu
- Institute of Plant Protection, Ningxia Academy of Agricultural and Forestry Sciences, Yinchuan, China
| | - Gadi V. P. Reddy
- Department of Entomology, Lousiana State University, Baton Rouge, Los Angeles, USA
| | - Hu Li
- MARA Key Laboratory of Surveillance and Management for Plant Quarantine Pests, College of Plant Protection, China Agricultural University, Beijing, China
- Sanya Institute of China Agricultural University, China Agricultural University, Sanya, China
| | - Zhihong Li
- MARA Key Laboratory of Surveillance and Management for Plant Quarantine Pests, College of Plant Protection, China Agricultural University, Beijing, China
- Sanya Institute of China Agricultural University, China Agricultural University, Sanya, China
| | - Yucheng Sun
- Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Zihua Zhao
- MARA Key Laboratory of Surveillance and Management for Plant Quarantine Pests, College of Plant Protection, China Agricultural University, Beijing, China
- Sanya Institute of China Agricultural University, China Agricultural University, Sanya, China
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Awori RM, Hendre P, Amugune NO. The genome of a steinernematid-associated Pseudomonas piscis bacterium encodes the biosynthesis of insect toxins. Access Microbiol 2023; 5:000659.v3. [PMID: 37970093 PMCID: PMC10634486 DOI: 10.1099/acmi.0.000659.v3] [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: 06/28/2023] [Accepted: 09/15/2023] [Indexed: 11/17/2023] Open
Abstract
Several species of soil-dwelling Steinernema nematodes are used in the biocontrol of crop pests, due to their natural capacity to kill diverse lepidopteran species. Although this insect-killing trait is known to be augmented by the nematodes' Xenorhabdus endosymbionts, the role of other steinernematid-associated bacterial genera in the nematode lifecycle remains unclear. This genomic study aimed to determine the potential of Pseudomonas piscis to contribute to the entomopathogenicity of its Steinernema host. Insect larvae were infected with three separate Steinernema cultures. From each of the three treatments, the prevalent bacteria in the haemocoel of cadavers, four days post-infection, were isolated. These three bacterial isolates were morphologically characterised. DNA was extracted from each of the three bacterial isolates and used for long-read genome sequencing and assembly. Assemblies were used to delineate species and identify genes that encode insect toxins, antimicrobials, and confer antibiotic resistance. We assembled three complete genomes. Through digital DNA-DNA hybridisation analyses, we ascertained that the haemocoels of insect cadavers previously infected with Steinernema sp. Kalro, Steinernema sp. 75, and Steinernema sp. 97 were dominated by Xenorhabdus griffiniae Kalro, Pseudomonas piscis 75, and X. griffiniae 97, respectively. X. griffiniae Kalro and X. griffiniae 97 formed a subspecies with other X. griffiniae symbionts of steinernematids from Kenya. P. piscis 75 phylogenetically clustered with pseudomonads that are characterised by high insecticidal activity. The P. piscis 75 genome encoded the production pathway of insect toxins such as orfamides and rhizoxins, antifungals such as pyrrolnitrin and pyoluteorin, and the broad-spectrum antimicrobial 2,4-diacetylphloroglucinol. The P. piscis 75 genome encoded resistance to over ten classes of antibiotics, including cationic lipopeptides. Steinernematid-associated P. piscis bacteria hence have the biosynthetic potential to contribute to nematode entomopathogenicity.
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Affiliation(s)
- Ryan Musumba Awori
- Elakistos Biosciences, P. O. Box 19301-00100, Nairobi, Kenya
- International Centre for Research on Agroforestry, P. O. Box 30677-00100, Nairobi, Kenya
| | - Prasad Hendre
- International Centre for Research on Agroforestry, P. O. Box 30677-00100, Nairobi, Kenya
| | - Nelson O. Amugune
- Department of Biology, University of Nairobi, P. O. Box 30197-00100, Nairobi, Kenya
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Zhang X, Hu Z, Wang S, Yin F, Wei Y, Xie J, Sun R. Discovery of 2-Naphthol from the Leaves of Actephila merrilliana as a Natural Nematicide Candidate. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:13209-13219. [PMID: 37643159 DOI: 10.1021/acs.jafc.3c02580] [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: 08/31/2023]
Abstract
To identify natural nematicides that can replace chemical nematicides, 2-naphthol with high activity against Meloidogyne incognita was isolated from Actephila merrilliana. The nematicidal activity of 2-naphthol against M. incognita was 100% at 100 μg/mL with an EC50 value of 38.00 μg/mL. Moreover, 2-naphthol had a significant negative effect on egg incubation. 2-Naphthol effectively inhibited the invasion of M. incognita into crops in both a pot experiment and field trial. In addition, the structure-activity relationship indicated that the naphthalene ring and its β-site hydroxyl group were the key pharmacophores for the nematicidal activity of 2-naphthol. Nematodes were stimulated by 2-naphthol to produce excessive reactive oxygen species, which may be the underlying mechanism of 2-naphthol nematicidal activity. A systemic evaluation of 2-naphthol in tomato plants demonstrated that 2-naphthol remained mainly fixed in the roots after being absorbed by the crop and was not transported to the stems or leaves. Thus, 2-naphthol can be developed as a natural nematicide candidate.
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Affiliation(s)
- Xi Zhang
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests, Ministry of Education, School of Plant Protection, Hainan University, Haikou 570228, People's Republic of China
| | - Zhan Hu
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests, Ministry of Education, School of Plant Protection, Hainan University, Haikou 570228, People's Republic of China
| | - Shuai Wang
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests, Ministry of Education, School of Plant Protection, Hainan University, Haikou 570228, People's Republic of China
| | - Fengman Yin
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests, Ministry of Education, School of Plant Protection, Hainan University, Haikou 570228, People's Republic of China
| | - Yuyang Wei
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests, Ministry of Education, School of Plant Protection, Hainan University, Haikou 570228, People's Republic of China
| | - Jia Xie
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests, Ministry of Education, School of Plant Protection, Hainan University, Haikou 570228, People's Republic of China
| | - Ranfeng Sun
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests, Ministry of Education, School of Plant Protection, Hainan University, Haikou 570228, People's Republic of China
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Yuan B, Li B, Shen H, Duan J, Jia F, Maimaiti Y, Li Y, Li G. Identification of fabclavine derivatives, Fcl-7 and Fcl-8, from Xenorhabdus budapestensis as major antifungal natural products against Rhizoctonia solani. J Appl Microbiol 2023; 134:lxad190. [PMID: 37656887 DOI: 10.1093/jambio/lxad190] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 07/30/2023] [Accepted: 08/21/2023] [Indexed: 09/03/2023]
Abstract
AIMS Black scurf disease, caused by Rhizoctonia solani, is a severe soil-borne and tuber-borne disease, which occurs and spreads in potato growing areas worldwide and poses a serious threat to potato production. New biofungicide is highly desirable for addressing the issue, and natural products (NPs) from Xenorhabdus spp. provide prolific resources for biofungicide development. In this study, we aim to identify antifungal NPs from Xenorhabdus spp. for the management of this disease. METHODS AND RESULTS Out of the 22 Xenorhabdus strains investigated, Xenorhabdus budapestensis 8 (XBD8) was determined to be the most promising candidate with the measured IC50 value of its cell-free supernatant against R. solani as low as 0.19 ml l-1. The major antifungal compound in XBD8 started to be synthesized in the middle logarithmic phase and reached a stable level at stationary phase. Core gene deletion coupled with high-resolution mass spectrometry analysis determined the major antifungal NPs as fabclavine derivatives, Fcl-7 and 8, which showed broad-spectrum bioactivity against important pathogenic fungi. Impressively, the identified fabclavine derivatives effectively controlled black scurf disease in both greenhouse and field experiments, significantly improving tuber quality and increasing with marketable tuber yield from 29 300 to 35 494 kg ha-1, comparable with chemical fungicide fludioxonil. CONCLUSIONS The fabclavine derivatives Fcl-7 and 8 were determined as the major antifungal NPs in XBD8, which demonstrated a bright prospect for the management of black scurf disease.
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Affiliation(s)
- Baoming Yuan
- State Key Laboratory for Biology of Plant Diseases and Insect Pests/Key Laboratory of Control of Biological Hazard Factors (Plant Origin) for Agri-product Quality and Safety, Ministry of Agriculture, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100081, China
- College of Plant Protection, Hebei Agricultural University, Technological Innovation Center for Biological Control of Crop Diseases and Insect Pests of Hebei Province, Baoding 071000, China
| | - Beibei Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests/Key Laboratory of Control of Biological Hazard Factors (Plant Origin) for Agri-product Quality and Safety, Ministry of Agriculture, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100081, China
- Functional and Evolutionary Entomology, Gembloux Agro-Bio Tech, University of Liège, B-5030 Gembloux, Belgium
| | - Hongfei Shen
- State Key Laboratory for Biology of Plant Diseases and Insect Pests/Key Laboratory of Control of Biological Hazard Factors (Plant Origin) for Agri-product Quality and Safety, Ministry of Agriculture, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Jiaqi Duan
- State Key Laboratory for Biology of Plant Diseases and Insect Pests/Key Laboratory of Control of Biological Hazard Factors (Plant Origin) for Agri-product Quality and Safety, Ministry of Agriculture, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Fenglian Jia
- State Key Laboratory for Biology of Plant Diseases and Insect Pests/Key Laboratory of Control of Biological Hazard Factors (Plant Origin) for Agri-product Quality and Safety, Ministry of Agriculture, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Yushanjiang Maimaiti
- Key Laboratory of Integrated Pest Management on Crops in Northwestern Oasis, Ministry of Agriculture and Rural Affairs, Research Institute of plant protection Xinjiang Academy of Agricultural Sciences, Urumqi, Xinjiang, 83009, China
| | - Yaning Li
- College of Plant Protection, Hebei Agricultural University, Technological Innovation Center for Biological Control of Crop Diseases and Insect Pests of Hebei Province, Baoding 071000, China
| | - Guangyue Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests/Key Laboratory of Control of Biological Hazard Factors (Plant Origin) for Agri-product Quality and Safety, Ministry of Agriculture, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100081, China
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Li B, Yuan B, Duan J, Qin Y, Shen H, Ren J, Francis F, Chen M, Li G. Identification of Fcl-29 as an Effective Antifungal Natural Product against Fusarium graminearum and Combinatorial Engineering Strategy for Improving Its Yield. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:5554-5564. [PMID: 36995163 DOI: 10.1021/acs.jafc.2c09012] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Fusarium head blight (FHB), caused by Fusarium graminearum, whose occurrence and prevalence causes 10-70% wheat production loss, is one of the most destructive diseases influencing the production of wheat globally. To identify the potential natural products (NPs) against F. graminearum, we screened 59 Xenorhabdus strains and discovered that the cell-free supernatant (CFS) of X. budapestensis 14 (XBD14) displays the highest bioactivity. Multiple genetic methods coupled with HRMS/MS analysis determined the major antifungal NP to be Fcl-29, a fabclavine derivative. Fcl-29 was found to effectively control FHB of wheat in the field test and demonstrated broad-spectrum antifungal activity against important pathogenic fungi. The production of Fcl-29 was dramatically improved by 33.82-fold with the combinatorial strategy of genetic engineering (1.66-fold) and fermentation engineering (20.39-fold). The exploration of a new biofungicide in global plant protection is now possible.
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Affiliation(s)
- Beibei Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests/Key Laboratory of Control of Biological Hazard Factors (Plant Origin) for Agri-Product Quality and Safety, Ministry of Agriculture, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100081, China
- Functional and Evolutionary Entomology, Gembloux Agro-Bio Tech, University of Liège, B-5030 Gembloux, Belgium
| | - Baoming Yuan
- State Key Laboratory for Biology of Plant Diseases and Insect Pests/Key Laboratory of Control of Biological Hazard Factors (Plant Origin) for Agri-Product Quality and Safety, Ministry of Agriculture, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Jiaqi Duan
- State Key Laboratory for Biology of Plant Diseases and Insect Pests/Key Laboratory of Control of Biological Hazard Factors (Plant Origin) for Agri-Product Quality and Safety, Ministry of Agriculture, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Youcai Qin
- State Key Laboratory for Biology of Plant Diseases and Insect Pests/Key Laboratory of Control of Biological Hazard Factors (Plant Origin) for Agri-Product Quality and Safety, Ministry of Agriculture, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Hongfei Shen
- State Key Laboratory for Biology of Plant Diseases and Insect Pests/Key Laboratory of Control of Biological Hazard Factors (Plant Origin) for Agri-Product Quality and Safety, Ministry of Agriculture, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Jie Ren
- State Key Laboratory for Biology of Plant Diseases and Insect Pests/Key Laboratory of Control of Biological Hazard Factors (Plant Origin) for Agri-Product Quality and Safety, Ministry of Agriculture, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Frédéric Francis
- Functional and Evolutionary Entomology, Gembloux Agro-Bio Tech, University of Liège, B-5030 Gembloux, Belgium
| | - Minghua Chen
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Guangyue Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests/Key Laboratory of Control of Biological Hazard Factors (Plant Origin) for Agri-Product Quality and Safety, Ministry of Agriculture, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100081, China
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10
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Vicente-Díez I, Pou A, Campos-Herrera R. The deterrent ability of Xenorhabdus nematophila and Photorhabdus laumondii compounds as a potential novel tool for Lobesia botrana (Lepidoptera: Tortricidae) management. J Invertebr Pathol 2023; 198:107911. [PMID: 36921888 DOI: 10.1016/j.jip.2023.107911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 03/03/2023] [Accepted: 03/06/2023] [Indexed: 03/14/2023]
Abstract
The grapevine moth, Lobesia botrana (Lepidoptera: Tortricidae), is a critical pest for vineyards and causes significant economic losses in wine-growing areas worldwide. Identifying and developing novel semiochemical cues (e.g. volatile bacterial compounds) which modify the ovipositional and trophic behaviour of L. botrana in vineyard fields could be a novel control alternative in viticulture. Xenorhabdus spp. and Photorhabdus spp. are becoming one of the best-studied bacterial species due to their potential interest in producing toxins and deterrent factors. In this study, we investigated the effect of the deterrent compounds produced by Xenorhabdus nematophila and Photorhabdus laumondii on the ovipositional moth behaviour and the larval feeding preference of L. botrana. Along with the in-vitro bioassays performed, we screened the potential use of 3 d cell-free bacterial supernatants and 3 and 5 d unfiltered bacterial ferments. In addition, we tested two application systems: (i) contact application of the bacterial compounds and (ii) volatile bacterial compounds application. Our findings indicate that the deterrent effectiveness varied with bacterial species, the use of bacterial cell-free supernatants or unfiltered fermentation product, and the culture times. Grapes soaked in the 3 d X. nematophila and P. laumondii ferments had ∼ 55% and ∼ 95% fewer eggs laid than the control, respectively. Likewise, the volatile compounds emitted by the 5 d P. laumondii fermentations resulted in ∼ 100% avoidance of L. botrana ovipositional activity for three days. Furthermore, both bacterial fermentation products have larval feeding deterrent effects (∼65% of the larva chose the control grapes), and they significantly reduced the severity of damage caused by third instar larva in treated grapes. This study provides insightful information about a novel bacteria-based tool which can be used as an eco-friendly and economical alternative in both organic and integrated control of L. botrana in vineyard.
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Affiliation(s)
- Ignacio Vicente-Díez
- Instituto de Ciencias de la Vid y del Vino (ICVV, Gobierno de La Rioja, CSIC, Universidad de La Rioja), Finca La GRajera, Ctra. Burgos Km. 6 Salida 13 Lo-20, Logroño 26007, Spain
| | - Alicia Pou
- Instituto de Ciencias de la Vid y del Vino (ICVV, Gobierno de La Rioja, CSIC, Universidad de La Rioja), Finca La GRajera, Ctra. Burgos Km. 6 Salida 13 Lo-20, Logroño 26007, Spain
| | - Raquel Campos-Herrera
- Instituto de Ciencias de la Vid y del Vino (ICVV, Gobierno de La Rioja, CSIC, Universidad de La Rioja), Finca La GRajera, Ctra. Burgos Km. 6 Salida 13 Lo-20, Logroño 26007, Spain.
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11
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Kim I, Heryanto C, Eleftherianos I. HETERORHABDITIS BACTERIOPHORA NEMATODES ARE SENSITIVE TO THE BACTERIAL PATHOGEN PHOTORHABDUS ASYMBIOTICA. J Parasitol 2023; 109:11-14. [PMID: 36805240 DOI: 10.1645/22-55] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
The entomopathogenic nematode (EPN) Heterorhabditis bacteriophora infects a wide range of insect hosts with the aid of its mutualistic bacteria Photorhabdus luminescens. While the mutualistic relationship between H. bacteriophora and P. luminescens and the infectivity of the nematode-bacteria complex have been characterized, how nematode fitness is affected by entomopathogenic bacteria existing in association with other EPN species remains poorly understood. In this study, the survival of H. bacteriophora infective juveniles containing or lacking P. luminescens was tested against the entomopathogenic bacteria Xenorhabdus nematophila and Photorhabdus asymbiotica as well as the non-pathogenic Escherichia coli. While X. nematophila and E. coli did not significantly affect the survival of H. bacteriophora, P. asymbiotica exerted a significant effect on nematode survival, particularly on those lacking P. luminescens. These results imply that P. asymbiotica encodes factors that are pathogenic to EPNs. Future efforts will focus on the identification of the bacterial molecular components that induce these effects. This study makes an important contribution to a growing body of research aimed at exploiting the full potential of nematode-bacterial complexes for eliminating noxious insect pests and treating infectious diseases caused by parasitic nematodes.
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Affiliation(s)
- Irene Kim
- Department of Biological Sciences, The George Washington University, Science and Engineering Hall, 22nd Street NW, Washington, D.C. 20052
| | - Christa Heryanto
- Department of Biological Sciences, The George Washington University, Science and Engineering Hall, 22nd Street NW, Washington, D.C. 20052
| | - Ioannis Eleftherianos
- Department of Biological Sciences, The George Washington University, Science and Engineering Hall, 22nd Street NW, Washington, D.C. 20052
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12
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Shen S, Ding B, Jiang X, Yang M, Yang Q, Dong L. Discovery of novel inhibitors targeting nematode chitinase C eCht1: Virtual screening, biological evaluation, and molecular dynamics simulation. Front Chem 2022; 10:1021295. [PMID: 36405330 PMCID: PMC9669442 DOI: 10.3389/fchem.2022.1021295] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 10/18/2022] [Indexed: 04/19/2024] Open
Abstract
Plant-parasitic nematodes are a main limiting factor for worldwide agriculture. To reduce the global burden of nematode infections, chemical nematicides are still the most effective methods to manage nematodes. With the increasing resistance of nematodes, the development of new anti-nematicides drug is urgent. Nematode chitinases are found to play important roles in various physiological functions, such as larva moulting, hatching from eggshell, and host infection. Inhibition of nematode chitinase is considered a promising strategy for the development of eco-friendly nematicides. In this study, to develop novel nematode chitinase CeCht1 inhibitors, virtual screening of the ZINC database was performed using the pesticide-likeness rules, pharmacophore-based and docking-based approach in turn. Compounds HAU-4 and HAU-7 were identified as potent CeCht1 inhibitors with the IC50 values of 4.2 μM and 10.0 μM, respectively. Moreover, molecular dynamics simulations combined with binding free energy and free energy decomposition calculations were conducted to investigate the basis for the potency of the two inhibitors toward CeCht1. This work gives an insight into the future rational development of novel and potent nematode chitinase inhibitors.
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Affiliation(s)
- Shengqiang Shen
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Baokang Ding
- State Key Laboratory of North China Crop Improvement and Regulation, College of Plant Protection, Hebei Agricultural University, Baoding, China
| | - Xi Jiang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
- Guangdong Laboratory for Lingnan Modern Agriculture (Shenzhen Branch), Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Meiling Yang
- State Key Laboratory of North China Crop Improvement and Regulation, College of Plant Protection, Hebei Agricultural University, Baoding, China
| | - Qing Yang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
- Guangdong Laboratory for Lingnan Modern Agriculture (Shenzhen Branch), Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Lili Dong
- State Key Laboratory of North China Crop Improvement and Regulation, College of Plant Protection, Hebei Agricultural University, Baoding, China
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13
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The Fight against Plant-Parasitic Nematodes: Current Status of Bacterial and Fungal Biocontrol Agents. Pathogens 2022; 11:pathogens11101178. [PMID: 36297235 PMCID: PMC9606992 DOI: 10.3390/pathogens11101178] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 10/08/2022] [Accepted: 10/10/2022] [Indexed: 11/24/2022] Open
Abstract
Plant-parasitic nematodes (PPNs) are among the most notorious and underrated threats to food security and plant health worldwide, compromising crop yields and causing billions of dollars of losses annually. Chemical control strategies rely heavily on synthetic chemical nematicides to reduce PPN population densities, but their use is being progressively restricted due to environmental and human health concerns, so alternative control methods are urgently needed. Here, we review the potential of bacterial and fungal agents to suppress the most important PPNs, namely Aphelenchoides besseyi, Bursaphelenchus xylophilus, Ditylenchus dipsaci, Globodera spp., Heterodera spp., Meloidogyne spp., Nacobbus aberrans, Pratylenchus spp., Radopholus similis, Rotylenchulus reniformis, and Xiphinema index.
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14
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Xenorhabdus spp.: An Overview of the Useful Facets of Mutualistic Bacteria of Entomopathogenic Nematodes. Life (Basel) 2022; 12:life12091360. [PMID: 36143397 PMCID: PMC9503066 DOI: 10.3390/life12091360] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 08/26/2022] [Accepted: 08/26/2022] [Indexed: 12/17/2022] Open
Abstract
Mounting concern over the misuse of chemical pesticides has sparked broad interest for safe and effective alternatives to control plant pests and pathogens. Xenorhabdus bacteria, as pesticidal symbionts of the entomopathogenic nematodes Steinernema species, can contribute to this solution with a treasure trove of insecticidal compounds and an ability to suppress a variety of plant pathogens. As many challenges face sound exploitation of plant–phytonematode interactions, a full useful spectrum of such interactions should address nematicidal activity of Xenorhabdus. Steinernema–Xenorhabdus complex or Xenorhabdus individually should be involved in mechanisms underlying the favorable side of plant–nematode interactions in emerging cropping systems. Using Xenorhabdus bacteria should earnestly be harnessed to control not only phytonematodes, but also other plant pests and pathogens within integrated pest management plans. This review highlights the significance of fitting Xenorhabdus-obtained insecticidal, nematicidal, fungicidal, acaricidal, pharmaceutical, antimicrobial, and toxic compounds into existing, or arising, holistic strategies, for controlling many pests/pathogens. The widespread utilization of Xenorhabdus bacteria, however, has been slow-going, due to costs and some issues with their commercial processing. Yet, advances have been ongoing via further mastering of genome sequencing, discovering more of the beneficial Xenorhabdus species/strains, and their successful experimentations for pest control. Their documented pathogenicity to a broad range of arthropods and pathogens and versatility bode well for useful industrial products. The numerous beneficial traits of Xenorhabdus bacteria can facilitate their integration with other tactics for better pest/disease management programs.
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15
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Dai K, Cao L, Huang Z, Gu X, Cui Y, Li J, Li Y, Xu C, Han R. Influence of entomopathogenic nematodes, symbiotic bacteria and ascarosides on the dispersal behaviour of Meloidogyne incognita. NEMATOLOGY 2022. [DOI: 10.1163/15685411-bja10184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Summary
Dispersal is an important behaviour for nematodes. Entomopathogenic nematodes (EPN) are able to regulate plant-parasitic nematodes in the field. However, the mechanism for the interactions between two types of nematodes is not clearly known. The effects of 12 synthesised ascarosides, three EPN species (Steinernema carpocapsae All, Heterorhabditis bacteriophora H06 and H. indica LN2), and 15 symbiotic bacterial isolates from EPN on the dispersal of Meloidogyne incognita were investigated. The results revealed that M. incognita juveniles were repelled, to various degrees, by most of the tested ascarosides (especially ascr#9), three species of EPN, and by bacterial isolates (especially TT01 from H. bacteriophora TT01 and H06 from H. bacteriophora H06), compared with the controls. Ascr#9 was abundant in M. incognita juvenile-conditioned supernatant. This provides useful cues for elucidating the interaction mechanism between two nematode groups and establishing alternative techniques for the safe and effective control of root-knot nematodes.
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Affiliation(s)
- Kang Dai
- Academy of Animal Husbandry and Veterinary Sciences, Qinghai University, Xining 810016, P.R. China
- 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, P.R. China
| | - Li Cao
- 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, P.R. China
| | - Zhihua Huang
- Yuxi Branch of Yunnan Tobacco Company, Engineering Center for Biological Control of Diseases and Pests in the Tobacco Industry, Yuxi 653100, Yunnan Province, P.R. China
| | - Xinghui Gu
- Yuxi Branch of Yunnan Tobacco Company, Engineering Center for Biological Control of Diseases and Pests in the Tobacco Industry, Yuxi 653100, Yunnan Province, P.R. China
| | - Yonghe Cui
- Yuxi Branch of Yunnan Tobacco Company, Engineering Center for Biological Control of Diseases and Pests in the Tobacco Industry, Yuxi 653100, Yunnan Province, P.R. China
| | - Jiangzhou Li
- Yuxi Branch of Yunnan Tobacco Company, Engineering Center for Biological Control of Diseases and Pests in the Tobacco Industry, Yuxi 653100, Yunnan Province, P.R. China
| | - Yuling Li
- Academy of Animal Husbandry and Veterinary Sciences, Qinghai University, Xining 810016, P.R. China
| | - Chengti Xu
- Academy of Animal Husbandry and Veterinary Sciences, Qinghai University, Xining 810016, P.R. China
| | - Richou Han
- 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, P.R. China
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16
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Natural products from Photorhabdus and Xenorhabdus: mechanisms and impacts. Appl Microbiol Biotechnol 2022; 106:4387-4399. [PMID: 35723692 DOI: 10.1007/s00253-022-12023-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Revised: 06/07/2022] [Accepted: 06/09/2022] [Indexed: 12/21/2022]
Abstract
Insects and fungal pathogens pose constant problems to public health and agriculture, especially in resource-limited parts of the world; and the use of chemical pesticides continues to be the main methods for the control of these organisms. Photorhabdus spp. and Xenorhabdus spp., (Fam; Morganellaceae), enteric symbionts of Steinernema, and Heterorhabditis nematodes are naturally found in soil on all continents, except Antarctic, and on many islands throughout the world. These bacteria produce diverse secondary metabolites that have important biological and ecological functions. Secondary metabolites include non-ribosomal peptides, polyketides, and/or hybrid natural products that are synthesized using polyketide synthetase (PRS), non-ribosomal peptide synthetase (NRPS), or similar enzymes and are sources of new pesticide/drug compounds and/or can serve as lead molecules for the design and synthesize of new alternatives that could replace current ones. This review addresses the effects of these bacterial symbionts on insect pests, fungal phytopathogens, and animal pathogens and discusses the substances, mechanisms, and impacts on agriculture and public health. KEY POINTS: • Insects and fungi are a constant menace to agricultural and public health. • Chemical-based control results in resistance development. • Photorhabdus and Xenorhabdus are compelling sources of biopesticides.
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