1
|
Chantab K, Rao Z, Zheng X, Han R, Cao L. Ascarosides and Symbiotic Bacteria of Entomopathogenic Nematodes Regulate Host Immune Response in Galleria mellonella Larvae. INSECTS 2024; 15:514. [PMID: 39057246 PMCID: PMC11277396 DOI: 10.3390/insects15070514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2024] [Revised: 06/20/2024] [Accepted: 06/27/2024] [Indexed: 07/28/2024]
Abstract
Insects protect themselves through their immune systems. Entomopathogenic nematodes and their bacterial symbionts are widely used for the biocontrol of economically important pests. Ascarosides are pheromones that regulate nematode behaviors, such as aggregation, avoidance, mating, dispersal, and dauer recovery and formation. However, whether ascarosides influence the immune response of insects remains unexplored. In this study, we co-injected ascarosides and symbiotic Photorhabdus luminescens subsp. kayaii H06 bacteria derived from Heterorhabditis bacteriophora H06 into the last instar larvae of Galleria mellonella. We recorded larval mortality and analyzed the expressions of AMPs, ROS/RNS, and LPSs. Our results revealed a process in which ascarosides, acting as enhancers of the symbiotic bacteria, co-induced G. mellonella immunity by significantly increasing oxidative stress responses and secreting AMPs (gallerimycin, gloverin, and cecropin). This led to a reduction in color intensity and the symbiotic bacteria load, ultimately resulting in delayed host mortality compared to either ascarosides or symbiotic bacteria. These findings demonstrate the cross-kingdom regulation of insects and symbiotic bacteria by nematode pheromones. Furthermore, our results suggest that G. mellonella larvae may employ nematode pheromones secreted by IJs to modulate insect immunity during early infection, particularly in the presence of symbiotic bacteria, for enhancing resistance to invasive bacteria in the hemolymph.
Collapse
Affiliation(s)
- Kanjana Chantab
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Science, Guangzhou 510260, China; (K.C.); (Z.R.); (X.Z.); (R.H.)
- Department of Plant Sciences, Faculty of Agriculture and Technology, Rajamangala University of Technology Isan, Surin 32000, Thailand
| | - Zhongchen Rao
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Science, Guangzhou 510260, China; (K.C.); (Z.R.); (X.Z.); (R.H.)
| | - Xuehong Zheng
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Science, Guangzhou 510260, China; (K.C.); (Z.R.); (X.Z.); (R.H.)
| | - 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 Science, Guangzhou 510260, China; (K.C.); (Z.R.); (X.Z.); (R.H.)
| | - 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 Science, Guangzhou 510260, China; (K.C.); (Z.R.); (X.Z.); (R.H.)
| |
Collapse
|
2
|
Arora S, Seth R, Singh Y, Seth RK. Effect of male parental gamma irradiation on host suitability of its F1 progeny of a lepidopteran tropical pest, Spodoptera litura (Fabr.) towards development and virulence of entomopathogenic nematodes, Steinernema thermophilum. Appl Radiat Isot 2024; 212:111426. [PMID: 38981166 DOI: 10.1016/j.apradiso.2024.111426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Revised: 06/27/2024] [Accepted: 07/04/2024] [Indexed: 07/11/2024]
Abstract
The suitability of F1 progeny insect larvae of the irradiated male parent, Spodoptera litura (Fabr.) for infective juveniles (IJs) of entomopathogenic nematodes (EPN), Steinernema thermophilum was assessed to comprehend the feasibility of combining EPNs with nuclear pest control tactic. As compared to the control, the IJs induced faster host mortality with reduced proliferation in F1 host larvae. IJs derived from F1 host larvae exhibited almost similar proliferation capacity on normal hosts as in control. Further, the molecular basis of EPNs induced mortality in F1 host larvae was evaluated. Dual stress of EPN infection and irradiation induced downregulation of the relative mRNA expression of antimicrobial genes and upregulated expression of antioxidative genes. A pronounced effect of EPNs in association with irradiation stress was apparent on host mortality. Radiation induced sterile F1 insect larvae of S. litura acted as a reasonably suitable host for EPNs and also provided the environment for developing viable EPNs for their potential use as biocontrol agents.
Collapse
Affiliation(s)
- Simran Arora
- Department of Zoology, University of Delhi, North Campus, Delhi, 110007, India
| | - Ranjana Seth
- Department of Zoology, University of Delhi, North Campus, Delhi, 110007, India
| | - Yogendra Singh
- Department of Zoology, University of Delhi, North Campus, Delhi, 110007, India
| | - R K Seth
- Department of Zoology, University of Delhi, North Campus, Delhi, 110007, India.
| |
Collapse
|
3
|
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.
Collapse
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
| |
Collapse
|
4
|
Trejo‐Meléndez VJ, Ibarra‐Rendón J, Contreras‐Garduño J. The evolution of entomopathogeny in nematodes. Ecol Evol 2024; 14:e10966. [PMID: 38352205 PMCID: PMC10862191 DOI: 10.1002/ece3.10966] [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: 09/01/2023] [Revised: 12/06/2023] [Accepted: 01/02/2024] [Indexed: 02/16/2024] Open
Abstract
Understanding how parasites evolved is crucial to understand the host and parasite interaction. The evolution of entomopathogenesis in rhabditid nematodes has traditionally been thought to have occurred twice within the phylum Nematoda: in Steinernematidae and Heterorhabditidae families, which are associated with the entomopathogenic bacteria Xenorhabdus and Photorhabdus, respectively. However, nematodes from other families that are associated with entomopathogenic bacteria have not been considered to meet the criteria for "entomopathogenic nematodes." The evolution of parasitism in nematodes suggests that ecological and evolutionary properties shared by families in the order Rhabditida favor the convergent evolution of the entomopathogenic trait in lineages with diverse lifestyles, such as saprotrophs, phoretic, and necromenic nematodes. For this reason, this paper proposes expanding the term "entomopathogenic nematode" considering the diverse modes of this attribute within Rhabditida. Despite studies are required to test the authenticity of the entomopathogenic trait in the reported species, they are valuable links that represent the early stages of specialized lineages to entomopathogenic lifestyle. An ecological and evolutionary exploration of these nematodes has the potential to deepen our comprehension of the evolution of entomopathogenesis as a convergent trait spanning across the Nematoda.
Collapse
Affiliation(s)
- V. J. Trejo‐Meléndez
- Edificio de Investigación I, ENES, Unidad Morelia, UNAMMoreliaMichoacánMexico
- Posgrado en Ciencias Biológicas, ENES, Unidad Morelia, UNAMMoreliaMichoacánMexico
| | - J. Ibarra‐Rendón
- Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV) – IrapuatoIrapuatoGuanajuatoMexico
| | - J. Contreras‐Garduño
- Edificio de Investigación I, ENES, Unidad Morelia, UNAMMoreliaMichoacánMexico
- Institute for Evolution and BiodiversityUniversity of MünsterMünsterGermany
| |
Collapse
|
5
|
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.
Collapse
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
| |
Collapse
|
6
|
Bastin A, Eleftherianos I. Functional role of the TGF-β signaling in the Drosophila immune response. CURRENT RESEARCH IN IMMUNOLOGY 2023; 4:100071. [PMID: 37810404 PMCID: PMC10556577 DOI: 10.1016/j.crimmu.2023.100071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 09/20/2023] [Accepted: 09/25/2023] [Indexed: 10/10/2023] Open
Abstract
TGF-β signaling pathways are present in diverse animal species, which indicates their evolutionary importance in modulating several conserved biological processes and maintaining host homeostasis by adjusting the activity of innate immune mechanisms. Drosophila melanogaster utilizes two related but separable cascades of the canonical TGF-β signaling pathway: The Bone Morphogenetic Protein and Activin branches. Recent studies have produced significant information on the immune role of TGF-β signaling in the fruit fly model during response against certain bacterial pathogens. Results from further investigations have generated novel insights into the role of Drosophila TGF-β signaling molecules as immune regulators opposing infection against nematode parasites and their mutualistic bacterial partners. This knowledge has revealed a previously unknown layer of the host innate immune system. Here we summarize these recent breakthroughs focusing on the participation of TGF-β signaling factors in various Drosophila immune processes in relation to infection with potent bacteria and nematode parasites. The presented information provides important clues indicating directions for future research into the design of novel strategies for the effective control of infectious diseases caused by bacterial pathogens and parasitic nematodes.
Collapse
Affiliation(s)
- Ashley Bastin
- Infection and Innate Immunity Laboratory, Department of Biological Sciences, The George Washington University, Washington DC, 20052, USA
| | - Ioannis Eleftherianos
- Infection and Innate Immunity Laboratory, Department of Biological Sciences, The George Washington University, Washington DC, 20052, USA
| |
Collapse
|
7
|
Huynh T, O'Halloran D, Hawdon J, Eleftherianos I. The nematode parasite Steinernema hermaphroditum is pathogenic to Drosophila melanogaster larvae without activating their immune response. MICROPUBLICATION BIOLOGY 2023; 2023:10.17912/micropub.biology.000944. [PMID: 37822685 PMCID: PMC10562934 DOI: 10.17912/micropub.biology.000944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 08/20/2023] [Accepted: 08/24/2023] [Indexed: 10/13/2023]
Abstract
Entomopathogenic nematodes are commonly used to control insect pest populations in the field. They also contribute substantially to understanding the molecular basis of nematode pathogenicity and insect anti-nematode immunity. Here, we tested the effect of the entomopathogenic nematode Steinernema hermaphroditum on the survival and immune signaling regulation of Drosophila melanogaster wild type larvae. Our results indicate that S. hermaphroditum infective juveniles are pathogenic toward D. melanogaster larvae, but they fail to activate certain immune pathway readout genes. These findings imply that S. hermaphroditum employs mechanisms that allow these parasitic nematodes to interfere with the D. melanogaster immune system.
Collapse
Affiliation(s)
- Tien Huynh
- Department of Biological Sciences, The George Washington University, Washington, DC, USA
| | - Damien O'Halloran
- Department of Biological Sciences, The George Washington University, Washington, DC, USA
| | - John Hawdon
- Department of Microbiology, Immunology, and Tropical Medicine, The George Washington University, Washington, DC, USA
| | - Ioannis Eleftherianos
- Department of Biological Sciences, The George Washington University, Washington, DC, USA
| |
Collapse
|
8
|
Shaik HA, Mishra A. Influence of Asafoetida Extract on the Virulence of the Entomopathogenic Nematode Steinernema carpocapsae and Its Symbiotic Bacterium Xenorhabdus nematophila in the Host Pyrrhocoris apterus. Microorganisms 2023; 11:1678. [PMID: 37512851 PMCID: PMC10385281 DOI: 10.3390/microorganisms11071678] [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: 04/29/2023] [Revised: 06/11/2023] [Accepted: 06/21/2023] [Indexed: 07/30/2023] Open
Abstract
Nematode-microbe symbiosis plays a key role in determining pathogenesis against pests. The modulation of symbiotic bacteria may affect the virulence of entomopathogenic nematodes (EPNs) and the biological management of pests. We tested the influence of asafoetida (ASF) extract on the virulence of Steinernema carpocapsae and its symbiotic bacterium, Xenorhabdus nematophila, in Pyrrhocoris apterus. A total of 100 mg of ASF killed 30% of EPNs in 48 h, while P. apterus remained unaffected. The EPNs pre-treated with 100 mg of ASF influenced P. apterus's mortality by 24-91.4% during a period of 24 to 72 h. The topical application of ASF acted as a deterrent to S. carpocapsae, lowering host invasion to 70% and delaying infectivity with 30% mortality for 168 h. Interestingly, Steinernema's symbiotic bacterium, Xenorhabdus, remained unaffected by ASF. An in vitro turbidity test containing 100 mg of ASF in a medium increased the growth rate of Xenorhabdus compared to a control. A disc diffusion assay confirmed the non-susceptibility of Xenorhabdus to ASF compared to a positive control, streptomycin. Pro-phenol oxidase (PPO) and phenol oxidase (PO) upregulation showed that ASF influences immunity, while EPN/ASF showed a combined immunomodulatory effect in P. apterus. We report that ASF modulated the virulence of S. carpocapsae but not that of its symbiotic bacterium, X. nematophila, against P. apterus.
Collapse
Affiliation(s)
- Haq Abdul Shaik
- Institute of Entomology, Biology Centre, CAS, Branišovská 31, 37005 České Budějovice, Czech Republic
| | - Archana Mishra
- South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Faculty of Fisheries and Protection of Waters, Institute of Aquaculture and Protection of Waters, University of South Bohemia in České Budějovice, Na Sádkách 1780, 37005 České Budějovice, Czech Republic
| |
Collapse
|
9
|
Maushe D, Ogi V, Divakaran K, Verdecia Mogena AM, Himmighofen PA, Machado RAR, Towbin BD, Ehlers RU, Molina C, Parisod C, Maud Robert CA. Stress tolerance in entomopathogenic nematodes: Engineering superior nematodes for precision agriculture. J Invertebr Pathol 2023:107953. [PMID: 37336478 DOI: 10.1016/j.jip.2023.107953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 06/13/2023] [Accepted: 06/16/2023] [Indexed: 06/21/2023]
Abstract
Entomopathogenic nematodes (EPNs) are soil-dwelling parasitic roundworms commonly used as biocontrol agents of insect pests in agriculture. EPN dauer juveniles locate and infect a host in which they will grow and multiply until resource depletion. During their free-living stage, EPNs face a series of internal and environmental stresses. Their ability to overcome these challenges is crucial to determine their infection success and survival. In this review, we provide a comprehensive overview of EPN response to stresses associated with starvation, low/elevated temperatures, desiccation, osmotic stress, hypoxia, and ultra-violet light. We further report EPN defense strategies to cope with biotic stressors such as viruses, bacteria, fungi, and predatory insects. By comparing the genetic and biochemical basis of these strategies to the nematode model Caenorhabditis elegans, we provide new avenues and targets to select and engineer precision nematodes adapted to specific field conditions.
Collapse
Affiliation(s)
- Dorothy Maushe
- Institute of Plant Sciences, University of Bern, Altenbergrain 21, CH-3013 Bern, Switzerland
| | - Vera Ogi
- Institute of Plant Sciences, University of Bern, Altenbergrain 21, CH-3013 Bern, Switzerland
| | - Keerthi Divakaran
- Institute of Plant Sciences, University of Bern, Altenbergrain 21, CH-3013 Bern, Switzerland
| | | | - Paul Anton Himmighofen
- Institute of Plant Sciences, University of Bern, Altenbergrain 21, CH-3013 Bern, Switzerland
| | - Ricardo A R Machado
- Institute of Biology, University of Neuchâtel, Rue Emile Argand 11, CH-2000 Neuchâtel, Switzerland
| | - Benjamin Daniel Towbin
- Institute of Cell Biology, University of Bern, Baltzerstrasse 4, CH-3012 Bern, Switzerland
| | - Ralf-Udo Ehlers
- e- nema GmbH, Klausdorfer Str. 28-36, DE-24223 Schwentinental, Germany
| | - Carlos Molina
- e- nema GmbH, Klausdorfer Str. 28-36, DE-24223 Schwentinental, Germany
| | - Christian Parisod
- Department of Biology, University of Fribourg, Chemin du Musée 10, CH-1700 Fribourg, Switzerland
| | - Christelle Aurélie Maud Robert
- Institute of Plant Sciences, University of Bern, Altenbergrain 21, CH-3013 Bern, Switzerland; Oeschger Centre for Climate Change Research, University of Bern, Hochschulstrasse 4, CH-3012 Bern, Switzerland.
| |
Collapse
|
10
|
Li F, Zhu Q, Dai M, Shu Q, Li X, Guo X, Wang Y, Wei J, Liu W, Dai Y, Li B. Tachinid parasitoid Exorista japonica affects the utilization of diet by changing gut microbial composition in the silkworm, Bombyx mori. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2023; 113:e22011. [PMID: 36938839 DOI: 10.1002/arch.22011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 02/17/2023] [Accepted: 03/03/2023] [Indexed: 05/16/2023]
Abstract
Changes in both intake and digestion of feed have been demonstrated in the host following parasitization. However, its regulatory mechanism has not been clarified. In this study, silkworms and Exorista japonica were used as research objects to analyze the effect of parasitism on the midgut immune system of the silkworm. After being parasitized, the expressions of antimicrobial peptide (AMP) genes of silkworms showed a fluctuating trend of first upregulation and then downregulation, while phenoloxidase and lysozyme activities were inhibited. To study the possible impact of the downregulation of AMP genes on intestinal microorganisms, the characteristics of the intestinal microbial population of silkworms on the third day of parasitism were analyzed. The relative abundance of Firmicutes, Proteobacteria, and Bacteroidota decreased, while that of Actinobacteriota increased. The increased abundance of conditionally pathogenic bacteria Serratia and Staphylococcus might lead to a decrease in the amount of silkworm ingestion. Meanwhile, the abundance of Acinetobacter, Bacillus, Pseudomonas, and Enterobacter promotes an increase in the digestion of nutrients. This study indicated that the imbalance of intestinal microbial homeostasis caused by parasitism may affect the absorption and digestion of nutrients by the host. Collectively, our findings provided a new clue for further exploring the mechanism of nutrient transport among the host, parasitoid, and intestinal microorganisms.
Collapse
Affiliation(s)
- Fanchi Li
- School of Basic Medicine and Biological Sciences, Soochow University, Suzhou, Jiangsu, People's Republic of China
- Sericulture Institute of Soochow University, Suzhou, Jiangsu, People's Republic of China
| | - Qingyu Zhu
- School of Basic Medicine and Biological Sciences, Soochow University, Suzhou, Jiangsu, People's Republic of China
| | - Minli Dai
- School of Basic Medicine and Biological Sciences, Soochow University, Suzhou, Jiangsu, People's Republic of China
| | - Qilong Shu
- School of Basic Medicine and Biological Sciences, Soochow University, Suzhou, Jiangsu, People's Republic of China
| | - Xin Li
- School of Basic Medicine and Biological Sciences, Soochow University, Suzhou, Jiangsu, People's Republic of China
| | - Xiqian Guo
- School of Basic Medicine and Biological Sciences, Soochow University, Suzhou, Jiangsu, People's Republic of China
| | - Yuanfei Wang
- School of Basic Medicine and Biological Sciences, Soochow University, Suzhou, Jiangsu, People's Republic of China
| | - Jing Wei
- School of Basic Medicine and Biological Sciences, Soochow University, Suzhou, Jiangsu, People's Republic of China
- Sericulture Institute of Soochow University, Suzhou, Jiangsu, People's Republic of China
| | - Wei Liu
- Suzhou Taihu Snow Silk Co., Ltd, Suzhou, People's Republic of China
| | - Yan Dai
- Suzhou Taihu Snow Silk Co., Ltd, Suzhou, People's Republic of China
| | - Bing Li
- School of Basic Medicine and Biological Sciences, Soochow University, Suzhou, Jiangsu, People's Republic of China
- Sericulture Institute of Soochow University, Suzhou, Jiangsu, People's Republic of China
| |
Collapse
|
11
|
Topalović O, Geisen S. Nematodes as suppressors and facilitators of plant performance. THE NEW PHYTOLOGIST 2023; 238:2305-2312. [PMID: 37010088 DOI: 10.1111/nph.18925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 03/26/2023] [Indexed: 05/19/2023]
Abstract
Plant-nematode interactions are mainly considered from the negative aspect with a focus on plant-parasitic nematodes (PPNs), which is justified considering the agronomic losses caused by PPNs. Despite the fact that PPNs are outnumbered by nonparasitic free-living nematodes (FLNs), the functional importance of FLNs, especially with regard to plant performance, remains largely unknown. Here, we provide a comprehensive overview and most recent insights into soil nematodes by showing direct and indirect links of both PPNs and FLNs with plant performance. We especially emphasize the knowledge gaps and potential of FLNs as important indirect players in driving plant performance such as stimulating the resistance to pests via improving the disease suppressive activity of the rhizobiome. Together, we present a holistic view of soil nematodes as positive and negative contributors to plant performance, accentuating the positive but underexplored role of FLNs.
Collapse
Affiliation(s)
- Olivera Topalović
- Section of Terrestrial Ecology, University of Copenhagen, Copenhagen, DK-2100, Denmark
- Department of Nematology, Wageningen University and Research, Wageningen, 6708PB, the Netherlands
| | - Stefan Geisen
- Department of Nematology, Wageningen University and Research, Wageningen, 6708PB, the Netherlands
| |
Collapse
|
12
|
Garriga A, Toubarro D, Simões N, Morton A, García-Del-Pino F. The modulation effect of the Steinernema carpocapsae - Xenorhabdus nematophila complex on immune-related genes in Drosophila suzukii larvae. J Invertebr Pathol 2023; 196:107870. [PMID: 36493843 DOI: 10.1016/j.jip.2022.107870] [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: 04/06/2022] [Revised: 10/31/2022] [Accepted: 12/01/2022] [Indexed: 12/12/2022]
Abstract
Larvae of the invasive pest Drosophila suzukii are susceptible to the Steinernema carpocapsae - Xenorhabdus nematophila complex and an assessment of the immune-regulatory system activation in this insect was performed to understand the response to the nematode infection. The expressions of 14 immune-related genes of different pathways (Imd, Toll, Jak-STAT, ProPO, JNK, TGF-β) were analyzed using qRT-PCR to determine variations after nematode penetration (90 min and 4 h) and after bacterial release (14 h). Before the bacteria were present, the nematodes were not recognized by the immune system of the larvae and practically none of the analyzed pathways presented variations when compared with the non-infected larvae. However, after the X. nematophila were released, PGRP-LC was activated leading to the gene upregulation of antimicrobial peptides of both the Toll and Imd pathways. Interestingly, the cellular response was inactive during the infection course as Jak/STAT and pro-phenoloxidase genes remained unresponsive to the presence of both pathogens. These results illustrate how D. suzukii immune pathways responded differently to the nematode and bacteria along the infection course.
Collapse
Affiliation(s)
- A Garriga
- Departament de Biologia Animal, Biologia Vegetal i Ecologia, Facultat de Biociències, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain
| | - D Toubarro
- Centro de Biotecnologia dos Açores, Departamento de Biologia, Universidade dos Açores, Ponta Delgada, Portugal
| | - N Simões
- Centro de Biotecnologia dos Açores, Departamento de Biologia, Universidade dos Açores, Ponta Delgada, Portugal
| | - A Morton
- Departament de Biologia Animal, Biologia Vegetal i Ecologia, Facultat de Biociències, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain
| | - F García-Del-Pino
- Departament de Biologia Animal, Biologia Vegetal i Ecologia, Facultat de Biociències, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain.
| |
Collapse
|
13
|
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.
Collapse
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
| |
Collapse
|
14
|
Excreted secreted products from the parasitic nematode Steinernema carpocapsae manipulate the Drosophila melanogaster immune response. Sci Rep 2022; 12:14237. [PMID: 35987963 PMCID: PMC9392720 DOI: 10.1038/s41598-022-18722-7] [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: 07/02/2022] [Accepted: 08/18/2022] [Indexed: 12/21/2022] Open
Abstract
Steinernema carpocapsae is an entomopathogenic nematode (EPN) that rapidly infects and kills a wide range of insect hosts and has been linked to host immunosuppression during the initial stages of infection. The lethal nature of S. carpocapsae infections has previously been credited to its symbiotic bacteria; however, it has become evident that the nematodes are able to effectively kill their hosts independently through their excretion/secretion products (ESPs). Here we examined how the adult Drosophila melanogaster immune system is modulated in response to S. carpocapsae ESPs in an attempt to ascertain individual pathogenic contributions of the isolated compound. We found that the S. carpocapsae ESPs decrease the survival of D. melanogaster adult flies, they induce the expression of certain antimicrobial peptide-encoding genes, and they cause significant reduction in phenoloxidase enzyme activity and delay in the melanization response in males flies. We also report that S. carpocapsae ESPs affect hemocyte numbers in both male and female individuals. Our results indicate the manipulative role of EPN ESPs and reveal sex-specific differences in the host response against nematode infection factors. These findings are beneficial as they promote our understanding of the molecular basis of nematode pathogenicity and the parasite components that influence nematode-host interactions.
Collapse
|
15
|
Swart Z, Duong TA, Wingfield BD, Postma A, Slippers B. The relevance of studying insect-nematode interactions for human disease. Pathog Glob Health 2022; 116:140-145. [PMID: 34726122 PMCID: PMC9090338 DOI: 10.1080/20477724.2021.1996796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
Vertebrate-parasitic nematodes cause debilitating, chronic infections in millions of people worldwide. The burden of these so-called 'neglected tropical diseases' is often carried by poorer socioeconomic communities in part because research on parasitic nematodes and their vertebrate hosts is challenging and costly. However, complex biological and pathological processes can be modeled in simpler organisms. Here, we consider how insight into the interactions between entomopathogenic nematodes (EPN), their insect hosts and bacterial symbionts may reveal novel treatment targets for parasitic nematode infections. We argue that a combination of approaches that target nematodes, as well as the interaction of pathogens with insect vectors and bacterial symbionts, offer potentially effective, but underexplored opportunities.
Collapse
Affiliation(s)
- Zorada Swart
- Department of Biochemistry Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, South Africa
| | - Tuan A. Duong
- Department of Biochemistry Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, South Africa
| | - Brenda D. Wingfield
- Department of Biochemistry Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, South Africa
| | - Alisa Postma
- Department of Biochemistry Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, South Africa
| | - Bernard Slippers
- Department of Biochemistry Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, South Africa
| |
Collapse
|
16
|
Matuska-Łyżwa J, Żarnowiec P, Kaca W. Comparison of Biological Activity of Field Isolates of Steinernema feltiae with a Commercial S. feltiae Biopesticide Product. INSECTS 2021; 12:816. [PMID: 34564257 PMCID: PMC8466843 DOI: 10.3390/insects12090816] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 09/02/2021] [Accepted: 09/09/2021] [Indexed: 11/21/2022]
Abstract
Insect trap studies were carried out to determine the presence of entomopathogenic nematodes (EPN) from the family Steinernematidae in the soils of Poland and to compare the biological activities of field nematode isolates with nematodes from commercial biopesticide. The fauna of these organisms in central Poland is poorly studied in both taxonomic and biological terms. Tilled soils representative of this region were sampled from cultivated fields. EPN were isolated from soil samples under laboratory conditions and identified using a key for species identification and molecular analysis. Basic morphometric parameters of infective juveniles and adult males of the first generation were determined. The research showed that males and infective juveniles Steinernema feltiae from Łoniów were the largest. The smallest infective juveniles were found in the isolate from Oblasy, and the smallest males in the isolate from Danków. In Poland, new field isolates showed close genetic similarity to other S. feltiae isolates. The research showed that the field isolates from Poland had greater infectivity and rate of reproduction compared with nematodes from the commercial biopesticide. The findings indicate the potential use of field S. feltiae isolates from Poland (iso1Lon, iso1Dan and iso1Obl) to develop new biopesticide products.
Collapse
Affiliation(s)
- Joanna Matuska-Łyżwa
- Department of Microbiology and Parasitology, Institute of Biology, Faculty of Natural Sciences, Jan Kochanowski University in Kielce, Uniwersytecka 7, 25-406 Kielce, Poland; (P.Ż.); (W.K.)
| | | | | |
Collapse
|
17
|
Zhang C, Wickham JD, Zhao L, Sun J. A new bacteria-free strategy induced by MaGal2 facilitates pinewood nematode escape immune response from its vector beetle. INSECT SCIENCE 2021; 28:1087-1102. [PMID: 32443173 DOI: 10.1111/1744-7917.12823] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 04/24/2020] [Accepted: 05/04/2020] [Indexed: 05/17/2023]
Abstract
Symbiotic microbes play a crucial role in regulating parasite-host interactions; however, the role of bacterial associates in parasite-host interactions requires elucidation. In this study, we showed that, instead of introducing numerous symbiotic bacteria, dispersal of 4th-stage juvenile (JIV ) pinewood nematodes (PWNs), Bursaphelenchus xylophilus, only introduced few bacteria to its vector beetle, Monochamus alternatus (Ma). JIV showed weak binding ability to five dominant bacteria species isolated from the beetles' pupal chamber. This was especially the case for binding to the opportunistic pathogenic species Serratia marcescens; the nematodes' bacteria binding ability at this critical stage when it infiltrates Ma for dispersal was much weaker compared with Caenorhabditis elegans, Diplogasteroides asiaticus, and propagative-stage PWN. The associated bacterium S. marcescens, which was isolated from the beetles' pupal chambers, was unfavorable to Ma, because it caused a higher mortality rate upon injection into tracheae. In addition, S. marcescens in the tracheae caused more immune effector disorders compared with PWN alone. Ma_Galectin2 (MaGal2), a pattern-recognition receptor, was up-regulated following PWN loading. Recombinant MaGal2 protein formed aggregates with five dominant associated bacteria in vitro. Moreover, MaGal2 knockdown beetles had up-regulated prophenoloxidase gene expression, increased phenoloxidase activity, and decreased PWN loading. Our study revealed a previously unknown strategy for immune evasion of this plant pathogen inside its vector, and provides novel insights into the role of bacteria in parasite-host interactions.
Collapse
Affiliation(s)
- Chi Zhang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| | - Jacob D Wickham
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Lilin Zhao
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| | - Jianghua Sun
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| |
Collapse
|
18
|
De Mandal S, Panda AK, Murugan C, Xu X, Senthil Kumar N, Jin F. Antimicrobial Peptides: Novel Source and Biological Function With a Special Focus on Entomopathogenic Nematode/Bacterium Symbiotic Complex. Front Microbiol 2021; 12:555022. [PMID: 34335484 PMCID: PMC8318700 DOI: 10.3389/fmicb.2021.555022] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 06/14/2021] [Indexed: 01/05/2023] Open
Abstract
The rapid emergence of multidrug resistant microorganisms has become one of the most critical threats to public health. A decrease in the effectiveness of available antibiotics has led to the failure of infection control, resulting in a high risk of death. Among several alternatives, antimicrobial peptides (AMPs) serve as potential alternatives to antibiotics to resolve the emergence and spread of multidrug-resistant pathogens. These small proteins exhibit potent antimicrobial activity and are also an essential component of the immune system. Although several AMPs have been reported and characterized, studies associated with their potential medical applications are limited. This review highlights the novel sources of AMPs with high antimicrobial activities, including the entomopathogenic nematode/bacterium (EPN/EPB) symbiotic complex. Additionally, the AMPs derived from insects, nematodes, and marine organisms and the design of peptidomimetic antimicrobial agents that can complement the defects of therapeutic peptides have been used as a template.
Collapse
Affiliation(s)
- Surajit De Mandal
- Laboratory of Bio-Pesticide Creation and Application of Guangdong Province, College of Agriculture, South China Agricultural University, Guangzhou, China
| | | | - Chandran Murugan
- SRM Research Institute, SRM Institute of Science and Technology, Kattankulathur, India
| | - Xiaoxia Xu
- Laboratory of Bio-Pesticide Creation and Application of Guangdong Province, College of Agriculture, South China Agricultural University, Guangzhou, China
| | | | - Fengliang Jin
- Laboratory of Bio-Pesticide Creation and Application of Guangdong Province, College of Agriculture, South China Agricultural University, Guangzhou, China
| |
Collapse
|
19
|
Mastore M, Caramella S, Quadroni S, Brivio MF. Drosophila suzukii Susceptibility to the Oral Administration of Bacillus thuringiensis, Xenorhabdus nematophila and Its Secondary Metabolites. INSECTS 2021; 12:insects12070635. [PMID: 34357295 PMCID: PMC8305655 DOI: 10.3390/insects12070635] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/07/2021] [Accepted: 07/11/2021] [Indexed: 11/26/2022]
Abstract
Simple Summary In recent decades, climate change and the international fruit trade have favored the movement of allochthonous species such as harmful insects into new geographic areas. The settlement of phytophagous insects and vectors in new areas, where potential predators are often lacking, has increased the use of chemical insecticides for their control. The intensive use of these substances represents a serious problem for ecosystems and human health; a possible alternative to chemical control is biological control, i.e., the use of biological insecticides that are compatible with the environment. The aim of our work was to further improve biological control methods for the management of the dipteran Spotted Wing Drosophila, an insect recently introduced in America and Europe, which can damage thin-skinned fruit crops. The methodologies applied are based on the combined use of different entomopathogens, i.e., bacteria, fungi, nematodes, etc., harmful for insects, with the purpose of increasing their effectiveness. The results obtained show that the combined use of two entomopathogenic bacteria increases both the lethality and rapidity of action. From an application viewpoint, studies like this are essential to identify new methods and bioinsecticides and, once transferred to the field, can be crucial to eliminate or, at least, reduce the use of chemicals. Abstract Drosophila suzukii, Spotted Wing Drosophila (SWD), is a serious economic issue for thin-skinned fruit farmers. The invasion of this dipteran is mainly counteracted by chemical control methods; however, it would be desirable to replace them with biological control. All assays were performed with Bacillus thuringiensis (Bt), Xenorhabdus nematophila (Xn), and Xn secretions, administered orally in single or combination, then larval lethality was assessed at different times. Gut damage caused by Bt and the influence on Xn into the hemocoelic cavity was also evaluated. In addition, the hemolymph cell population was analyzed after treatments. The data obtained show that the combined use of Bt plus Xn secretions on larvae, compared to single administration of bacteria, significantly improved the efficacy and reduced the time of treatments. The results confirm the destructive action of Bt on the gut of SWD larvae, and that Bt-induced alteration promotes the passage of Xn to the hemocoel cavity. Furthermore, hemocytes decrease after bioinsecticides treatments. Our study demonstrates that combining bioinsecticides can improve the efficacy of biocontrol and such combinations should be tested in greenhouse and in field in the near future.
Collapse
Affiliation(s)
- Maristella Mastore
- Laboratory of Comparative Immunology and Parasitology, Department of Theoretical and Applied Sciences, University of Insubria, 21100 Varese, Italy; (M.M.); (S.C.)
| | - Sara Caramella
- Laboratory of Comparative Immunology and Parasitology, Department of Theoretical and Applied Sciences, University of Insubria, 21100 Varese, Italy; (M.M.); (S.C.)
| | - Silvia Quadroni
- Laboratory of Ecology, Department of Theoretical and Applied Sciences, University of Insubria, 21100 Varese, Italy;
| | - Maurizio Francesco Brivio
- Laboratory of Comparative Immunology and Parasitology, Department of Theoretical and Applied Sciences, University of Insubria, 21100 Varese, Italy; (M.M.); (S.C.)
- Correspondence: ; Tel.: +39-0332-421404
| |
Collapse
|
20
|
Topalović O, Vestergård M. Can microorganisms assist the survival and parasitism of plant-parasitic nematodes? Trends Parasitol 2021; 37:947-958. [PMID: 34162521 DOI: 10.1016/j.pt.2021.05.007] [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: 02/23/2021] [Revised: 05/19/2021] [Accepted: 05/20/2021] [Indexed: 12/14/2022]
Abstract
Plant-parasitic nematodes (PPNs) remain a hardly treatable problem in many crops worldwide. Low efficacy of many biocontrol agents may be due to negligence of the native microbiota that is naturally associated with nematodes in soil, and which may protect nematodes against microbial antagonists. This phenomenon is more extensively studied for other nematode parasites, so we compiled these studies and drew parallels to the existing knowledge on PPN. We describe how microbial-mediated modulation of host immune responses facilitate nematode parasitism and discuss the role of Caenorhabditis elegans-protective microbiota to get an insight into the microbial protection of PPNs in soil. Molecular mechanisms of PPN-microbial interactions are also discussed. An understanding of microbial-aided PPN performance is thus pivotal for efficient management of PPNs.
Collapse
Affiliation(s)
- Olivera Topalović
- Aarhus University, Institute for Agroecology, Faculty of Technical Sciences, Aarhus University, 4200, Slagelse, Denmark.
| | - Mette Vestergård
- Aarhus University, Institute for Agroecology, Faculty of Technical Sciences, Aarhus University, 4200, Slagelse, Denmark.
| |
Collapse
|
21
|
Susceptibility of Drosophila suzukii larvae to the combined administration of the entomopathogens Bacillus thuringiensis and Steinernema carpocapsae. Sci Rep 2021; 11:8149. [PMID: 33854098 PMCID: PMC8046782 DOI: 10.1038/s41598-021-87469-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Accepted: 03/30/2021] [Indexed: 02/06/2023] Open
Abstract
Non-native pests are often responsible for serious crop damage. Since Drosophila suzukii has invaded North America and Europe, the global production of soft, thin-skinned fruits has suffered severe losses. The control of this dipteran by pesticides, although commonly used, is not recommended because of the negative impact on the environment and human health. A possible alternative is the use of bio-insecticides, including Bacillus thuringiensis and entomopathogenic nematodes, such as Steinernema carpocapsae. These biological control agents have a fair effectiveness when used individually on D. suzukii, but both have limits related to different environmental, methodological, and physiological factors. In this work, we tested various concentrations of B. thuringiensis and S. carpocapsae to evaluate their efficacy on D. suzukii larvae, when administered individually or in combination by using agar traps. In the combined trials, we added the nematodes after 16 h or concurrently to the bacteria, and assessed larvae lethality from 16 to 48 h. The assays demonstrated a higher efficacy of the combined administration, both time-shifted and concurrent; the obtained data also showed a relevant decrease of the time needed to kill the larvae. Particularly, the maximum mortality rate, corresponding to 79% already at 16 h, was observed with the highest concentrations (0.564 µg/mL of B. thuringiensis and 8 × 102 IJs of S. carpocapsae) in the concurrent trials. This study, conducted by laboratory tests under controlled conditions, is a good starting point to develop a further application step through field studies for the control of D. suzukii.
Collapse
|
22
|
Goodrich-Blair H. Interactions of host-associated multispecies bacterial communities. Periodontol 2000 2021; 86:14-31. [PMID: 33690897 DOI: 10.1111/prd.12360] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The oral microbiome comprises microbial communities colonizing biotic (epithelia, mucosa) and abiotic (enamel) surfaces. Different communities are associated with health (eg, immune development, pathogen resistance) and disease (eg, tooth loss and periodontal disease). Like any other host-associated microbiome, colonization and persistence of both beneficial and dysbiotic oral microbiomes are dictated by successful utilization of available nutrients and defense against host and competitor assaults. This chapter will explore these general features of microbe-host interactions through the lens of symbiotic (mutualistic and antagonistic/pathogenic) associations with nonmammalian animals. Investigations in such systems across a broad taxonomic range have revealed conserved mechanisms and processes that underlie the complex associations among microbes and between microbes and hosts.
Collapse
Affiliation(s)
- Heidi Goodrich-Blair
- Department of Microbiology, University of Tennessee-Knoxville, Knoxville, Tennessee, USA
| |
Collapse
|
23
|
Bobardt SD, Dillman AR, Nair MG. The Two Faces of Nematode Infection: Virulence and Immunomodulatory Molecules From Nematode Parasites of Mammals, Insects and Plants. Front Microbiol 2020; 11:577846. [PMID: 33343521 PMCID: PMC7738434 DOI: 10.3389/fmicb.2020.577846] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 11/02/2020] [Indexed: 12/20/2022] Open
Abstract
Helminths stage a powerful infection that allows the parasite to damage host tissue through migration and feeding while simultaneously evading the host immune system. This feat is accomplished in part through the release of a diverse set of molecules that contribute to pathogenicity and immune suppression. Many of these molecules have been characterized in terms of their ability to influence the infectious capabilities of helminths across the tree of life. These include nematodes that infect insects, known as entomopathogenic nematodes (EPN) and plants with applications in agriculture and medicine. In this review we will first discuss the nematode virulence factors, which aid parasite colonization or tissue invasion, and cause many of the negative symptoms associated with infection. These include enzymes involved in detoxification, factors essential for parasite development and growth, and highly immunogenic ES proteins. We also explore how these parasites use several classes of molecules (proteins, carbohydrates, and nucleic acids) to evade the host's immune defenses. For example, helminths release immunomodulatory molecules in extracellular vesicles that may be protective in allergy and inflammatory disease. Collectively, these nematode-derived molecules allow parasites to persist for months or even years in a host, avoiding being killed or expelled by the immune system. Here, we evaluate these molecules, for their individual and combined potential as vaccine candidates, targets for anthelminthic drugs, and therapeutics for allergy and inflammatory disease. Last, we evaluate shared virulence and immunomodulatory mechanisms between mammalian and non-mammalian plant parasitic nematodes and EPNs, and discuss the utility of EPNs as a cost-effective model for studying nematode-derived molecules. Better knowledge of the virulence and immunomodulatory molecules from both entomopathogenic nematodes and soil-based helminths will allow for their use as beneficial agents in fighting disease and pests, divorced from their pathogenic consequences.
Collapse
Affiliation(s)
- Sarah D. Bobardt
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, CA, United States
| | - Adler R. Dillman
- Department of Nematology, University of California, Riverside, Riverside, CA, United States
| | - Meera G. Nair
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, CA, United States
| |
Collapse
|
24
|
Brivio MF, Mastore M. When Appearance Misleads: The Role of the Entomopathogen Surface in the Relationship with Its Host. INSECTS 2020; 11:E387. [PMID: 32585858 PMCID: PMC7348879 DOI: 10.3390/insects11060387] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 06/18/2020] [Accepted: 06/20/2020] [Indexed: 12/14/2022]
Abstract
Currently, potentially harmful insects are controlled mainly by chemical synthetic insecticides, but environmental emergencies strongly require less invasive control techniques. The use of biological insecticides in the form of entomopathogenic organisms is undoubtedly a fundamental resource for the biological control of insect pests in the future. These infectious agents and endogenous parasites generally act by profoundly altering the host's physiology to death, but their success is closely related to the neutralization of the target insect's immune response. In general, entomopathogen parasites, entomopathogenic bacteria, and fungi can counteract immune processes through the effects of secretion/excretion products that interfere with and damage the cells and molecules typical of innate immunity. However, these effects are observed in the later stages of infection, whereas the risk of being recognized and neutralized occurs very early after penetration and involves the pathogen surface components and molecular architecture; therefore, their role becomes crucial, particularly in the earliest pathogenesis. In this review, we analyze the evasion/interference strategies that entomopathogens such as the bacterium Bacillus thuringiensis, fungi, nematocomplexes, and wasps implement in the initial stages of infection, i.e., the phases during which body or cell surfaces play a key role in the interaction with the host receptors responsible for the immunological discrimination between self and non-self. In this regard, these organisms demonstrate evasive abilities ascribed to their body surface and cell wall; it appears that the key process of these mechanisms is the capability to modify the surface, converting it into an immunocompatible structure, or interaction that is more or less specific to host factors.
Collapse
Affiliation(s)
- Maurizio Francesco Brivio
- Laboratory of Comparative Immunology and Parasitology, Department of Theoretical and Applied Sciences, University of Insubria, 21100 Varese, Italy;
| | | |
Collapse
|
25
|
Roy MC, Kim Y. Tolerance of the mealworm beetle, Tenebrio molitor, to an entomopathogenic nematode, Steinernema feltiae, at two infection foci, the intestine and the hemocoel. J Invertebr Pathol 2020; 174:107428. [PMID: 32553640 DOI: 10.1016/j.jip.2020.107428] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 06/08/2020] [Accepted: 06/10/2020] [Indexed: 12/27/2022]
Abstract
An entomopathogenic nematode, Steinernema feltiae K1, exhibits pathogenicity in various insect hosts, however, its virulence among the target insect species varies. Specifically, a coleopteran insect, Tenebrio molitor, is less susceptible to S. feltiae than are lepidopteran insects. We analyzed the low virulence of S. feltiae against T. molitor sequentially, in entering the gut lumen and penetrating the hemocoel, and in hemocoelic immune defenses by comparing the responses to those of a lepidopteran insect, Spodoptera exigua. Infective juveniles (IJs) of S. feltiae exhibited higher virulence and produced more progeny IJs in S. exigua than in T. molitor. The difference in IJ behavior was observed in the IJ invasion rate (IJs in gut lumen/IJs treated) after treatment, in which a lower rate was observed in T. molitor (20.4%) than in S. exigua (55.5%). Also, a lower hemocoelic penetration rate of IJs (IJs in hemocoel/IJs in gut) was observed in T. molitor (54%) than in S. exigua (74%) 24 h after feeding treatment. To investigate the immune defense in the hemocoel, insect hemolymph samples were incubated with IJs. The encapsulation behavior and phenoloxidase activity was higher in T. molitor hemolymph than in S. exigua hemolymph, which resulted in a significantly higher nematicidal activity in S. exigua. The humoral immune responses against S. feltiae were also different between the two species. The expression of two antimicrobial peptides, cecropin and attacin 1, was much higher in T. molitor. Furthermore, eicosanoid biosynthetic activity against S. feltiae was different in the two host species; sPLA2 activity was highly inducible in T. molitor but not in S. exigua. These results suggest that variability of the immune defense in the target insects, as well as in the invasion and penetration rates of IJs to the hemocoel, plays a crucial role in determining the insecticidal virulence of S. feltiae.
Collapse
Affiliation(s)
- Miltan Chandra Roy
- Department of Plant Medicals, Andong National University, Andong 36729, Republic of Korea
| | - Yonggyun Kim
- Department of Plant Medicals, Andong National University, Andong 36729, Republic of Korea.
| |
Collapse
|
26
|
Garriga A, Mastore M, Morton A, Garcia del Pino F, Brivio MF. Immune Response of Drosophila suzukii Larvae to Infection with the Nematobacterial Complex Steinernema carpocapsae-Xenorhabdus nematophila. INSECTS 2020; 11:insects11040210. [PMID: 32231138 PMCID: PMC7240654 DOI: 10.3390/insects11040210] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 03/19/2020] [Accepted: 03/26/2020] [Indexed: 01/06/2023]
Abstract
Entomopathogenic nematodes have been proposed as biological agents for the control of Drosophila suzukii, an invasive pest of small-stone and soft-skinned fruits. Larvae of the fly are susceptible to Steinernema carpocapsae infection but the reaction of immune defenses of the host are unknown. To determine the immune response, larvae were infected with S. carpocapsae and Xenorhabdus nematophila to evaluate the effector mechanisms of both humoral and cellular processes. The symbiont bacteria presented an inhibitory effect on the phenoloxidase cascade with a low level of melanization. Besides, X. nematophila activated the synthesis of putative antimicrobial peptides on the hemolymph of infected larvae. However, those peptides presented a lower antimicrobial activity compared to hemolymph from larvae infected with non-symbiont bacteria. Xenorhabdus nematophila avoided also the phagocytosis response of hemocytes. During in vitro and in vivo assays, S. carpocapsae was not encapsulated by cells, unless the cuticle was damaged with a lipase-treatment. Hemocyte counts confirmed differentiation of lamellocytes in the early phase of infection despite the unrecognition of the nematodes. Both X. nematophila and S. carpocapsae avoided the cellular defenses of D. suzukii larvae and depressed the humoral response. These results confirmed the potential of entomopathogenic nematodes to control D. suzukii.
Collapse
Affiliation(s)
- Anna Garriga
- Departament de Biologia Animal, Biologia Vegetal i Ecologia, Facultat de Biociències, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain; (A.G.); (A.M.)
| | - Maristella Mastore
- Laboratory of Comparative Immunology and Parasitology, Department of Theoretical and Applied Sciences, University of Insubria, 21100 Varese, Italy;
| | - Ana Morton
- Departament de Biologia Animal, Biologia Vegetal i Ecologia, Facultat de Biociències, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain; (A.G.); (A.M.)
| | - Fernando Garcia del Pino
- Departament de Biologia Animal, Biologia Vegetal i Ecologia, Facultat de Biociències, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain; (A.G.); (A.M.)
- Correspondence: (F.G.d.P.); (M.F.B.); Tel.: +39-0332-421404 (M.F.B.)
| | - Maurizio Francesco Brivio
- Laboratory of Comparative Immunology and Parasitology, Department of Theoretical and Applied Sciences, University of Insubria, 21100 Varese, Italy;
- Correspondence: (F.G.d.P.); (M.F.B.); Tel.: +39-0332-421404 (M.F.B.)
| |
Collapse
|
27
|
Thioester-containing Proteins in the Drosophila melanogaster Immune Response against the Pathogen Photorhabdus. INSECTS 2020; 11:insects11020085. [PMID: 32013030 PMCID: PMC7073583 DOI: 10.3390/insects11020085] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 01/22/2020] [Accepted: 01/23/2020] [Indexed: 12/22/2022]
Abstract
The fruit fly Drosophila melanogaster forms a magnificent model for interpreting conserved host innate immune signaling and functional processes in response to microbial assaults. In the broad research field of host-microbe interactions, model hosts are used in conjunction with a variety of pathogenic microorganisms to disentangle host immune system activities and microbial pathogenicity strategies. The pathogen Photorhabdus is considered an established model for analyzing bacterial virulence and symbiosis due to its unique life cycle that extends between two invertebrate hosts: an insect and a parasitic nematode. In recent years, particular focus has been given to the mechanistic participation of the D. melanogaster thioester-containing proteins (TEPs) in the overall immune capacity of the fly upon response against the pathogen Photorhabdus alone or in combination with its specific nematode vector Heterorhabditis bacteriophora. The original role of certain TEPs in the insect innate immune machinery was linked to the antibacterial and antiparasite reaction of the mosquito malaria vector Anopheles gambiae; however, revamped interest in the immune competence of these molecules has recently emerged from the D. melanogaster-Photorhabdus infection system. Here, we review the latest findings on this topic with the expectation that such information will refine our understanding of the evolutionary immune role of TEPs in host immune surveillance.
Collapse
|
28
|
Chandra Roy M, Lee D, Kim Y. Host Immunosuppression Induced by Steinernema feltiae, an Entomopathogenic Nematode, through Inhibition of Eicosanoid Biosynthesis. INSECTS 2019; 11:insects11010033. [PMID: 31906089 PMCID: PMC7023448 DOI: 10.3390/insects11010033] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 12/27/2019] [Accepted: 12/28/2019] [Indexed: 02/06/2023]
Abstract
Steinernema feltiae K1 (Filipjev) (Nematode: Steinernematidae), an entomopathogenic nematode, was isolated and identified based on its morphological and molecular diagnostic characteristics. Its infective juveniles (IJs) were highly pathogenic to three lepidopteran (LC50 = 23.7–25.0 IJs/larva) and one coleopteran (LC50 = 39.3 IJs/larva) insect species. Infected larvae of the diamondback moth, Plutella xylostella (L.) (Insecta: Lepidoptera), exhibited significant reduction in phospholipase A2 (PLA2) activity in their plasma. The decrease of PLA2 activity was followed by significant septicemia of the larvae infected with S. feltiae. Insecticidal activity induced by S. feltiae was explained by significant immunosuppression in cellular immune responses measured by hemocyte nodule formation and total hemocyte count (THC). Although S. feltiae infection suppressed nodule formation and THC in the larvae, an addition of arachidonic acid (AA, a catalytic product of PLA2) rescued these larvae from fatal immunosuppression. In contrast, an addition of dexamethasone (a specific PLA2 inhibitor) enhanced the nematode’s pathogenicity in a dose-dependent manner. To discriminate the immunosuppressive activity of a symbiotic bacterium (Xenorhabdus bovienii (Proteobacteria: Enterobacterales)) from the nematode, kanamycin was applied to after nematode infection. It significantly inhibited the bacterial growth in the hemolymph. Compared to nematode treatment alone, the addition of antibiotics to nematode infection partially rescued the immunosuppression measured by phenol oxidase activity. Consequently, treatment with antibiotics significantly rescued the larvae from the insecticidal activity of S. feltiae. These results suggest that immunosuppression induced by infection of S. feltiae depends on its symbiotic bacteria by inhibiting eicosanoid biosynthesis, resulting in significant insect mortality. However, the addition of antibiotics or AA could not completely rescue the virulence of the nematode, suggesting that the nematode itself also plays a role in its insecticidal activity.
Collapse
Affiliation(s)
- Miltan Chandra Roy
- Department of Plant Medicals, Andong National University, Andong 36729, Korea;
| | - Dongwoon Lee
- School of Environmental Ecology and Tourism, Kyungpook National University, Sangju 37224, Korea;
| | - Yonggyun Kim
- Department of Plant Medicals, Andong National University, Andong 36729, Korea;
- Correspondence: ; Tel.: +82-54-820-5638
| |
Collapse
|
29
|
Chevée V, Sachar U, Yadav S, Heryanto C, Eleftherianos I. The peptidoglycan recognition protein PGRP-LE regulates the Drosophila immune response against the pathogen Photorhabdus. Microb Pathog 2019; 136:103664. [PMID: 31404632 DOI: 10.1016/j.micpath.2019.103664] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 08/09/2019] [Accepted: 08/09/2019] [Indexed: 12/15/2022]
Abstract
Photorhabdus bacteria are potent pathogens of insects and humans. To elucidate the infection strategies Photorhabdus employs to subvert the host innate immune response, it is critical to use model organisms that permit the genetic dissection of the dynamics involved in host-pathogen interactions. Here, we employed the fruit fly Drosophila melanogaster to interrogate the role of the immune deficiency (Imd) pathway receptor peptidoglycan recognition protein LE (PGRP-LE) in the regulation of the fly's response to the insect pathogen Photorhabdus luminescens and the insect/human pathogen P. asymbiotica. We show that PGRP-LE is upregulated in response to injection of Photorhabdus bacteria in background control flies, and that loss-of-function PGRP-LE mutant flies are more sensitive specifically to P. luminescens infection and harbor a higher bacterial burden of this species compared to background controls. Also, our results indicate that the absence of functional PGRP-LE alters the transcriptional pathway activity of Imd and Jnk signaling upon infection with P. asymbiotica, while infection with P. luminescens modifies the activity of Jak/Stat signaling. These findings denote the participation of the PGRP-LE receptor in the response of D. melanogaster to Photorhabdus challenge and contribute to a better understanding of pathogen detection and host immune regulation against virulent microbial invaders.
Collapse
Affiliation(s)
- Victoria Chevée
- Infection and Innate Immunity Lab, Department of Biological Sciences, 800 22nd Street NW, Washington, DC, 200 52, USA
| | - Upasana Sachar
- Infection and Innate Immunity Lab, Department of Biological Sciences, 800 22nd Street NW, Washington, DC, 200 52, USA
| | - Shruti Yadav
- Infection and Innate Immunity Lab, Department of Biological Sciences, 800 22nd Street NW, Washington, DC, 200 52, USA
| | - Christa Heryanto
- Infection and Innate Immunity Lab, Department of Biological Sciences, 800 22nd Street NW, Washington, DC, 200 52, USA
| | - Ioannis Eleftherianos
- Infection and Innate Immunity Lab, Department of Biological Sciences, 800 22nd Street NW, Washington, DC, 200 52, USA.
| |
Collapse
|
30
|
Ogier JC, Pagès S, Galan M, Barret M, Gaudriault S. rpoB, a promising marker for analyzing the diversity of bacterial communities by amplicon sequencing. BMC Microbiol 2019; 19:171. [PMID: 31357928 PMCID: PMC6664775 DOI: 10.1186/s12866-019-1546-z] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 07/18/2019] [Indexed: 12/20/2022] Open
Abstract
Background Microbiome composition is frequently studied by the amplification and high-throughput sequencing of specific molecular markers (metabarcoding). Various hypervariable regions of the 16S rRNA gene are classically used to estimate bacterial diversity, but other universal bacterial markers with a finer taxonomic resolution could be employed. We compared specificity and sensitivity between a portion of the rpoB gene and the V3 V4 hypervariable region of the 16S rRNA gene. Results We first designed universal primers for rpoB suitable for use with Illumina sequencing-based technology and constructed a reference rpoB database of 45,000 sequences. The rpoB and V3 V4 markers were amplified and sequenced from (i) a mock community of 19 bacterial strains from both Gram-negative and Gram-positive lineages; (ii) bacterial assemblages associated with entomopathogenic nematodes. In metabarcoding analyses of mock communities with two analytical pipelines (FROGS and DADA2), the estimated diversity captured with the rpoB marker resembled the expected composition of these mock communities more closely than that captured with V3 V4. The rpoB marker had a higher level of taxonomic affiliation, a higher sensitivity (detection of all the species present in the mock communities), and a higher specificity (low rates of spurious OTU detection) than V3 V4. We compared the performance of the rpoB and V3 V4 markers in an animal ecosystem model, the infective juveniles of the entomopathogenic nematode Steinernema glaseri carrying the symbiotic bacteria Xenorhabdus poinarii. Both markers showed the bacterial community associated with this nematode to be of low diversity (< 50 OTUs), but only rpoB reliably detected the symbiotic bacterium X. poinarii. Conclusions Our results confirm that different microbiota composition data may be obtained with different markers. We found that rpoB was a highly appropriate marker for assessing the taxonomic structure of mock communities and the nematode microbiota. Further studies on other ecosystems should be considered to evaluate the universal usefulness of the rpoB marker. Our data highlight two crucial elements that should be taken into account to ensure more reliable and accurate descriptions of microbial diversity in high-throughput amplicon sequencing analyses: i) the need to include mock communities as controls; ii) the advantages of using a multigenic approach including at least one housekeeping gene (rpoB is a good candidate) and one variable region of the 16S rRNA gene. This study will be useful to the growing scientific community describing bacterial communities by metabarcoding in diverse ecosystems. Electronic supplementary material The online version of this article (10.1186/s12866-019-1546-z) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
| | - Sylvie Pagès
- DGIMI, INRA, University Montpellier, 34095, Montpellier, France
| | - Maxime Galan
- CBGP INRA CIRAD IRD Montpellier SupAgro, Univ. Montpellier, 755 avenue du Campus Agropolis, CS 300 16, F-34988, Montferrier sur Lez cedex, France
| | - Matthieu Barret
- INRA AGROCAMPUS-Ouest, Universite d'Angers, Beaucouze, France
| | | |
Collapse
|
31
|
Liao C, Zheng M, Chen Y, Wang M, Li B. Immunosuppression mechanism of entomopathogenic bacteria against Galleria mellonella larvae. Process Biochem 2019. [DOI: 10.1016/j.procbio.2019.03.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
|
32
|
Chang DZ, Serra L, Lu D, Mortazavi A, Dillman AR. A core set of venom proteins is released by entomopathogenic nematodes in the genus Steinernema. PLoS Pathog 2019; 15:e1007626. [PMID: 31042778 PMCID: PMC6513111 DOI: 10.1371/journal.ppat.1007626] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 05/13/2019] [Accepted: 02/07/2019] [Indexed: 11/26/2022] Open
Abstract
Parasitic helminths release molecular effectors into their hosts and these effectors can directly damage host tissue and modulate host immunity. Excreted/secreted proteins (ESPs) are one category of parasite molecular effectors that are critical to their success within the host. However, most studies of nematode ESPs rely on in vitro stimulation or culture conditions to collect the ESPs, operating under the assumption that in vitro conditions mimic actual in vivo infection. This assumption is rarely if ever validated. Entomopathogenic nematodes (EPNs) are lethal parasites of insects that produce and release toxins into their insect hosts and are a powerful model parasite system. We compared transcriptional profiles of individual Steinernema feltiae nematodes at different time points of activation under in vitro and in vivo conditions and found that some but not all time points during in vitro parasite activation have similar transcriptional profiles with nematodes from in vivo infections. These findings highlight the importance of experimental validation of ESP collection conditions. Additionally, we found that a suite of genes in the neuropeptide pathway were downregulated as nematodes activated and infection progressed in vivo, suggesting that these genes are involved in host-seeking behavior and are less important during active infection. We then characterized the ESPs of activated S. feltiae infective juveniles (IJs) using mass spectrometry and identified 266 proteins that are released by these nematodes. In comparing these ESPs with those previously identified in activated S. carpocapsae IJs, we identified a core set of 52 proteins that are conserved and present in the ESPs of activated IJs of both species. These core venom proteins include both tissue-damaging and immune-modulating proteins, suggesting that the ESPs of these parasites include both a core set of effectors as well as a specialized set, more adapted to the particular hosts they infect.
Collapse
Affiliation(s)
- Dennis Z. Chang
- Department of Nematology, University of California, Riverside, California, United States of America
| | - Lorrayne Serra
- Department of Developmental and Cell Biology, Center for Complex Biological Systems, University of California, Irvine, California, United States of America
| | - Dihong Lu
- Department of Nematology, University of California, Riverside, California, United States of America
| | - Ali Mortazavi
- Department of Developmental and Cell Biology, Center for Complex Biological Systems, University of California, Irvine, California, United States of America
| | - Adler R. Dillman
- Department of Nematology, University of California, Riverside, California, United States of America
| |
Collapse
|
33
|
Mastore M, Quadroni S, Toscano A, Mottadelli N, Brivio MF. Susceptibility to entomopathogens and modulation of basal immunity in two insect models at different temperatures. J Therm Biol 2018; 79:15-23. [PMID: 30612676 DOI: 10.1016/j.jtherbio.2018.11.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 10/31/2018] [Accepted: 11/12/2018] [Indexed: 11/30/2022]
Abstract
In this work, we analysed the efficacy of different commercial bio-insecticides (Steinernema feltiae, Steinernema carpocapsae, Heterorhabditis bacteriophora and Bacillus thuringiensis) by valuating the mortality induced on two insect models, Galleria mellonella (Lepidoptera) and Sarcophaga africa (Diptera) after exposure to different temperatures (10, 20 and 30 °C). Moreover, we investigated the effects of temperature on the basal humoral immunity of the two target insects; particularly, phenoloxidase (PO) and lysozyme activity. Our results show that G. mellonella is susceptible to all bio-insecticides at all the examined temperatures, except when infected at 10 °C with S. carpocapsae and at 30 °C with S. feltiae and B. thuringiensis. S. africa is more susceptible at 30 °C to all bioinsecticides; whereas, when infected at 10 and 20 °C, H. bacteriophora is the most efficient. Temperature modulates PO activity of both G. mellonella and S. africa, otherwise variations in lysozyme activity is observed only in G. mellonella. Except for a possible correlation between the increased lysozyme activity and the delayed Bt efficacy recorded on G. mellonella at 30 °C, a different resistance to bio-insecticides at different temperatures does not seem to be associated to variations of the host basal immunity, probably due to immunoevasive and immunodepressive strategies of these entomopathogens.
Collapse
Affiliation(s)
- Maristella Mastore
- Lab. of Comparative Immunology and Parasitology, Dept. of Theoretical and Applied Sciences, University of Insubria, Varese, Italy
| | - Silvia Quadroni
- Lab. of Ecology, Dept. of Science and High Technology, University of Insubria, Varese, Italy
| | - Andrea Toscano
- Lab. of Comparative Immunology and Parasitology, Dept. of Theoretical and Applied Sciences, University of Insubria, Varese, Italy
| | - Nicolò Mottadelli
- Lab. of Comparative Immunology and Parasitology, Dept. of Theoretical and Applied Sciences, University of Insubria, Varese, Italy
| | - Maurizio F Brivio
- Lab. of Comparative Immunology and Parasitology, Dept. of Theoretical and Applied Sciences, University of Insubria, Varese, Italy.
| |
Collapse
|