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Rique HL, Menezes HSG, Melo-Santos MAV, Silva-Filha MHNL. Evaluation of a long-lasting microbial larvicide against Culex quinquefasciatus and Aedes aegypti under laboratory and a semi-field trial. Parasit Vectors 2024; 17:391. [PMID: 39272177 PMCID: PMC11401406 DOI: 10.1186/s13071-024-06465-5] [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: 04/30/2024] [Accepted: 08/22/2024] [Indexed: 09/15/2024] Open
Abstract
BACKGROUND Microbial larvicides containing both LysiniBacillus sphaericus and Bacillus thuringiensis svar. israelensis (Bti) insecticidal crystals can display advantages for mosquito control. This includes a broader action against larvae that are refractory to the Binary (Bin) toxin from L. sphaericus, as Bin-resistant Culex quinquefasciatus and Aedes aegypti naturally refractory larvae, which often co-habit urban areas of endemic countries for arboviruses. Our principal goal was to assess the toxicity of a combined L. sphaericus/Bti larvicide (Vectomax FG™) to Cx. quinquefasciatus (susceptible CqS and Bin-resistant CqR) and Ae. aegypti (Rocke) and to determine its persistence in the breeding sites with those larvae. METHODS The toxicity of a combined L. sphaericus/Bti product (VectoMax FG™) to larvae was performed using bioassays, and persistence was evaluated in simulate field trials carried out under the shade, testing two label concentrations during 12 weeks. A laboratory strain SREC, established with CqS and CqR larvae, was kept during four generations to evaluate the ability of the L. sphaericus/Bti to eliminate resistant larvae. RESULTS The L. sphaericus/Bti showed toxicity (mg/L) to larvae from all strains with a decreasing pattern for CqS (LC50 = 0.006, LC90 = 0.030), CqR (LC50 = 0.009, LC90 = 0.069), and Rocke (LC50 = 0.042, LC90 = 0.086). In a simulated field trial, the larvicide showed a persistence of 6 weeks and 8 weeks, controlling larvae from all strains in containers with 100 L of water, using 2 g or 4 g per container (100 L), respectively. The treatment of SREC larvae with L. sphaericus/Bti showed its capacity to eliminate the Bin-resistant individuals using suitable concentrations to target those larvae. CONCLUSIONS Our results showed the high efficacy and persistence of the L. sphaericus/Bti larvicide to control Cx. quinquefasciatus and Ae. aegypti that might cohabit breeding sites. These findings demonstrated that such larvicides can be an effective tool for controlling those species in urban areas with a low potential for selecting resistance.
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Affiliation(s)
- Hyago Luiz Rique
- Departament of Entomology, Instituto Aggeu Magalhães-Fiocruz, Av. Moraes Rego S/N, Recife, PE, 50740-465, Brazil
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Zamnuri MAHB, Qiu S, Rizalmy MAAB, He W, Yusoff S, Roeroe KA, Du J, Loh KH. Integration of IoT in Small-Scale Aquaponics to Enhance Efficiency and Profitability: A Systematic Review. Animals (Basel) 2024; 14:2555. [PMID: 39272340 PMCID: PMC11393993 DOI: 10.3390/ani14172555] [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: 06/20/2024] [Revised: 08/24/2024] [Accepted: 09/01/2024] [Indexed: 09/15/2024] Open
Abstract
Aquaponics combines aquaculture and hydroponics to offer a sustainable approach to agriculture, addressing food security issues with minimal environmental harm. However, small-scale practitioners face challenges due to a lack of professional knowledge in water chemistry and system maintenance. Economic hurdles, such as operational costs and energy-intensive components, hinder the viability of small-scale aquaponics. Selecting suitable fish and plant species, along with appropriate stocking densities, is crucial. Media Bed (MB), Deep Water Culture (DWC), and the Nutrient Film Technique (NFT) are commonly used hydroponic techniques. This study outlines optimal conditions, including water quality, temperature, pH, and nutrient concentrations, essential for symbiotic fish and plant cultivation. Integrating IoT technology enhances efficiency and profitability by optimizing resource utilization, monitoring water quality, and ensuring optimal growth conditions. Knowledge sharing among practitioners fosters innovation and sustainability through collaborative learning and best practices exchange. Establishing a community for knowledge sharing is vital for continuous improvement, advancing small-scale aquaponics towards a more efficient and sustainable future.
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Affiliation(s)
| | - Shuting Qiu
- Institute of Ocean and Earth Science, Universiti Malaya, Kuala Lumpur 50603, Malaysia
- Key Laboratory of Marine Ecological Conservation and Restoration, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen 361005, China
- APEC Marine Sustainable Development Center, Xiamen 361005, China
| | | | - Weiyi He
- Institute of Ocean and Earth Science, Universiti Malaya, Kuala Lumpur 50603, Malaysia
- Key Laboratory of Marine Ecological Conservation and Restoration, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen 361005, China
| | - Sumiani Yusoff
- Institute of Ocean and Earth Science, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | | | - Jianguo Du
- Key Laboratory of Marine Ecological Conservation and Restoration, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen 361005, China
- APEC Marine Sustainable Development Center, Xiamen 361005, China
- Faculty of Marine Biology, Xiamen Ocean Vocational College, Xiamen 361100, China
| | - Kar-Hoe Loh
- Institute of Ocean and Earth Science, Universiti Malaya, Kuala Lumpur 50603, Malaysia
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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; 80:4231-4242. [PMID: 38619291 DOI: 10.1002/ps.8127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2023] [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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Zhang Q, Hua G, Smith L, Adang MJ. Scavenger Receptor C1 Mediates Toxicity of Binary Toxin from Lysinibacillus sphaericus to Ag55 Cells. Toxins (Basel) 2024; 16:369. [PMID: 39195779 PMCID: PMC11359365 DOI: 10.3390/toxins16080369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2024] [Revised: 08/01/2024] [Accepted: 08/13/2024] [Indexed: 08/29/2024] Open
Abstract
Lysinibacillus sphaericus harboring Binary (BinA and BinB) toxins is highly toxic against Anopheles and Culex mosquito larvae. The Anopheles Ag55 cell line is a suitable model for investigating the mode of Bin toxin action. Based on the low-levels of α-glycosidase Agm3 mRNA in Ag55 cells and the absence of detectable Agm3 proteins, we hypothesized that a scavenger receptor could be mediating Bin cytotoxicity. Preliminary RNA interference knockdown of the expressed scavenger receptors, combined with Bin cytotoxicity assays, was conducted. The scavenger Receptor C1 (SCRC1) became the focus of this study, as a putative receptor for Bin toxins in Ag55 cells, and SCRBQ2 was selected as a negative control. Open reading frames encoding SCRC1 and SCRBQ2 were cloned and expressed in vitro, and polyclonal antibodies were prepared for immunological analyses. The RNAi silencing of SCRC1 and SCRBQ2 resulted in the successful knockdown of both SCRC1 and SCRBQ2 transcripts and protein levels. The cytolytic toxicity of Bin against Ag55 cells was severely reduced after the SCRC1-RNAi treatment. The phagocytic receptor protein SCRC1 mediates endocytosis of the Bin toxin into Ag55 cells, thereby facilitating its internal cytological activity. The results support a mechanism of the Bin toxin entering Ag55 cells, possibly via SCRC1-mediated endocytosis, and encourage investigations into how Bin is transferred from its bound form on the midgut epithelial cells into the epithelial endocytic system.
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Affiliation(s)
- Qi Zhang
- College of Plant Protection, Shenyang Agricultural University, Shenyang 110866, China;
| | - Gang Hua
- Department of Entomology, University of Georgia, Athens, GA 30602-2603, USA
| | - Laramie Smith
- Department of Entomology, University of Georgia, Athens, GA 30602-2603, USA
| | - Michael J. Adang
- Department of Entomology, University of Georgia, Athens, GA 30602-2603, USA
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602-2603, USA
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Osborne CJ, Su T, Silver KS, Cohnstaedt LW. Variable gut pH as a potential mechanism of tolerance to Bacillus thuringiensis subsp. israelensis toxins in the biting midge Culicoides sonorensis. PEST MANAGEMENT SCIENCE 2024; 80:4006-4012. [PMID: 38527917 DOI: 10.1002/ps.8104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 03/04/2024] [Accepted: 03/24/2024] [Indexed: 03/27/2024]
Abstract
BACKGROUND Toxins of Bacillus thuringiensis subsp. israelensis (Bti) are safer alternatives for controlling dipteran pests such as black flies and mosquitoes. The biting midge Culicoides sonorensis (Diptera: Ceratopogonidae) is an important pest of livestock in much of the United States and larval midges utilize semi-aquatic habitats which are permissive for Bti product application. Reports suggest that Bti products are ineffective at killing biting midges despite their taxonomic relation to black flies and mosquitoes. Here, we investigate the toxicity of a Bti-based commercial insecticide and its active ingredient in larval Culicoides sonorensis. A suspected mechanism of Bti tolerance is an acidic larval gut, and we used a pH indicator dye to examine larval Culicoides sonorensis gut pH after exposure to Bti. RESULTS The lethal concentration to kill 90% (LC90) of larvae of the commercial product (386 mg/L) was determined to be almost 10 000 times more than that of some mosquito species, and no concentration of active ingredient tested achieved 50% larval mortality. The larval gut was found to be more acidic after exposure to Bti which inhibits Bti toxin activity. By comparison, 100% mortality was achieved in larval Aedes aegypti at the product's label rate for this species and mosquito larvae had alkaline guts regardless of treatment. Altering the larval rearing water to alkaline conditions enhanced Bti efficacy when using the active ingredient. CONCLUSION We conclude that Bti is not practical for larval Culicoides sonorensis control at the same rates as mosquitos but show that alterations or additives to the environment could make the products more effective. © 2024 Society of Chemical Industry.
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Affiliation(s)
- Cameron J Osborne
- Department of Entomology, Kansas State University, Manhattan, KS, USA
| | - Tianyun Su
- EcoZone International, Riverside, CA, USA
| | | | - Lee W Cohnstaedt
- Foreign Arthropod-Borne Animal Diseases Research Unit, Agricultural Research Service, United States Department of Agriculture, Manhattan, KS, USA
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Dunlap CA, Johnson ET, Burkett-Cadena M, Cadena J, Muturi EJ. Lysinibacillus pinottii sp. nov., a novel species with anti-mosquito and anti-mollusk activity. Antonie Van Leeuwenhoek 2024; 117:100. [PMID: 39001997 DOI: 10.1007/s10482-024-01993-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Accepted: 06/24/2024] [Indexed: 07/15/2024]
Abstract
An isolate of a Gram-positive, strictly aerobic, motile, rod-shaped, endospore forming bacterium was originally isolated from soil when screening and bioprospecting for plant beneficial microorganisms. Phylogenetic analysis of the 16S rRNA gene sequences indicated that this strain was closely related to Lysinibacillus fusiformis NRRL NRS-350T (99.7%) and Lysinibacillus sphaericus NRRL B-23268T (99.2%). In phenotypic characterization, the novel strain was found to grow between 10 and 45 °C and tolerate up to 8% (w/v) NaCl. Furthermore, the strain grew in media with pH 5 to 10 (optimal growth at pH 7.0). The predominant cellular fatty acids were observed to be iso-C15: 0 (52.3%), anteiso-C15: 0 (14.8%), C16:1ω7C alcohol (11.2%), and C16: 0 (9.5%). The cell-wall peptidoglycan contained lysine-aspartic acid, the same as congeners. A draft genome was assembled and the DNA G+C content was determined to be 37.1% (mol content). A phylogenomic analysis on the core genome of the new strain and 5 closest type strains of Lysinibacillus revealed this strain formed a distinct monophyletic clade with the nearest neighbor being Lysinibacillus fusiformis. DNA-DNA relatedness studies using in silico DNA-DNA hybridizations (DDH) showed this species was below the species threshold of 70%. Based upon the consensus of phylogenetic and phenotypic analyses, we conclude that this strain represents a novel species within the genus Lysinibacillus, for which the name Lysinibacillus pinottii sp. nov. is proposed, with type strain PB211T (= NRRL B-65672T, = CCUG 77181T).
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Affiliation(s)
- Christopher A Dunlap
- Crop Bioprotection Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, United States Department of Agriculture, Peoria, IL, USA.
| | - Eric T Johnson
- Crop Bioprotection Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, United States Department of Agriculture, Peoria, IL, USA
| | | | | | - Ephantus J Muturi
- Crop Bioprotection Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, United States Department of Agriculture, Peoria, IL, USA
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Mandodan S, Gangmei K, Vijayakumar A, Kunnikuruvan A, Lukose J, Padmanaban H, Bora B, Ashokkumar M, Irudayaraj G, Subbiah P. Molecular identification and GC-MS analysis of a newly isolated novel bacterium (Lysinibacillus sp. VCRC B655) for mosquito control. Mol Biol Rep 2024; 51:800. [PMID: 39001994 DOI: 10.1007/s11033-024-09734-9] [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: 05/07/2024] [Accepted: 06/17/2024] [Indexed: 07/15/2024]
Abstract
BACKGROUND Mosquitoes are widespread globally and have contributed to transmitting pathogens to humans and the burden of vector-borne diseases. They are effectively controlled at their larval stages by biocontrol agents. Unravelling natural sources for microbial agents can lead us to novel potential candidates for managing mosquito-borne diseases. In the present study, an attempt was made to isolate a novel bacterium from the field-collected agricultural soil for larvicidal activity and promising bacterial metabolites for human healthcare. METHODS AND RESULTS Field-collected soil samples from the Union territory of Puducherry, India, have been used as the source of bacteria. Isolate VCRC B655 belonging to the genus Lysinibacillus was identified by 16S rRNA gene sequencing and exhibited promising larvicidal activity against different mosquito species, including Culex (Cx.) quinquefasciatus, Anopheles (An.) stephensi, and Aedes (Ae.) aegypti. The lethal concentration (LC) of Lysinibacillus sp. VCRCB655 was observed to be high for Cx. quiquefasciatus: LC50 at 0.047 mg/l, LC90 at 0.086 mg/l, followed by An. stephensi and Ae. aegypti (LC50: 0.6952 mg/l and 0.795 mg/l) respectively. Additionally, metabolic profiling of the culture supernatant was carried out through Gas chromatography and Mass spectrophotometry (GC/MS) and identified 15 major secondary metabolites of different metabolic classes. Diketopiperazine (DKPs), notably pyro lo [1, 2-a] pyrazine1, 4-dione, are the abundant compounds reported for antioxidant activity, and an insecticide compound benzeneacetic acid was also identified. CONCLUSIONS A new bacterial isolate, Lysinibacillus sp. VCRC B655 has been identified with significant larvicidal activity against mosquito larvae with no observed in non-target organisms. GC-MS analysis revealed diverse bioactive compounds with substantial biological applications. In conclusion, Lysinibacillus sp. VCRC B655 showed promise as an alternative biocontrol agent for mosquito vector control, with additional biological applications further enhancing its significance.
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Affiliation(s)
- Sahadiya Mandodan
- Unit of Microbiology and Immunology (UMI), Department of Health Research (Ministry of Health & Family Welfare, Govt. of India), ICMR-Vector Control Research Centre (VCRC), Medical Complex Indira Nagar, Puducherry, 605006, India
| | - Kakhuangailiu Gangmei
- Unit of Microbiology and Immunology (UMI), Department of Health Research (Ministry of Health & Family Welfare, Govt. of India), ICMR-Vector Control Research Centre (VCRC), Medical Complex Indira Nagar, Puducherry, 605006, India
| | - Abhisubesh Vijayakumar
- Unit of Microbiology and Immunology (UMI), Department of Health Research (Ministry of Health & Family Welfare, Govt. of India), ICMR-Vector Control Research Centre (VCRC), Medical Complex Indira Nagar, Puducherry, 605006, India
| | - Aneha Kunnikuruvan
- Unit of Microbiology and Immunology (UMI), Department of Health Research (Ministry of Health & Family Welfare, Govt. of India), ICMR-Vector Control Research Centre (VCRC), Medical Complex Indira Nagar, Puducherry, 605006, India
| | - Jibi Lukose
- Unit of Microbiology and Immunology (UMI), Department of Health Research (Ministry of Health & Family Welfare, Govt. of India), ICMR-Vector Control Research Centre (VCRC), Medical Complex Indira Nagar, Puducherry, 605006, India
| | - Hemaladkshmi Padmanaban
- Unit of Microbiology and Immunology (UMI), Department of Health Research (Ministry of Health & Family Welfare, Govt. of India), ICMR-Vector Control Research Centre (VCRC), Medical Complex Indira Nagar, Puducherry, 605006, India
| | - Bhagyashree Bora
- Unit of Microbiology and Immunology (UMI), Department of Health Research (Ministry of Health & Family Welfare, Govt. of India), ICMR-Vector Control Research Centre (VCRC), Medical Complex Indira Nagar, Puducherry, 605006, India
| | - Mathivanan Ashokkumar
- Unit of Microbiology and Immunology (UMI), Department of Health Research (Ministry of Health & Family Welfare, Govt. of India), ICMR-Vector Control Research Centre (VCRC), Medical Complex Indira Nagar, Puducherry, 605006, India
| | - Geetha Irudayaraj
- Unit of Microbiology and Immunology (UMI), Department of Health Research (Ministry of Health & Family Welfare, Govt. of India), ICMR-Vector Control Research Centre (VCRC), Medical Complex Indira Nagar, Puducherry, 605006, India
| | - Poopathi Subbiah
- Unit of Microbiology and Immunology (UMI), Department of Health Research (Ministry of Health & Family Welfare, Govt. of India), ICMR-Vector Control Research Centre (VCRC), Medical Complex Indira Nagar, Puducherry, 605006, India.
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Negri A, Pezzali G, Pitton S, Piazzoni M, Soresinetti L, Naro G, Gabrieli P, Bettoni G, Bandi C, Caccia S, Epis S. The bio-larvicide Bacillus thuringiensis var. israelensis is effective against Aedes koreicus, either dissolved in water or delivered through eco-compatible chitosan-based hydrogels. CURRENT RESEARCH IN PARASITOLOGY & VECTOR-BORNE DISEASES 2024; 6:100197. [PMID: 39070230 PMCID: PMC11278931 DOI: 10.1016/j.crpvbd.2024.100197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Revised: 06/24/2024] [Accepted: 06/27/2024] [Indexed: 07/30/2024]
Abstract
Mosquito control, which is not always easily accomplished, is further complicated by the spread of invasive species. This is the case of Aedes koreicus, a mosquito native to East Asia, whose presence has been recorded in several European countries, including Italy. This mosquito found suitable ecological conditions in central Europe in general, and in northern Italy in particular, as shown by the ongoing expansion of its distribution. While basic knowledge on feeding habits of Ae. koreicus have already been acquired, information on its vectorial competence is scarce. Therefore, active monitoring on the presence of this mosquito, and the pre-planning of future control actions, are of paramount importance. Currently, there are no specific guidelines for controlling this mosquito, both in its native regions and in invaded countries. Here we present the first study on the efficacy of a bioinsecticide based on Bacillus thuringiensis on Ae. koreicus larvae, with a comparison with results obtained on the tiger mosquito Aedes albopictus. Our results proved that this bioinsecticide is effective on Ae. koreicus, both dissolved in water and incorporated into MosChito raft, a hydrogel-based matrix that has recently been developed for the delivery of insecticides to other mosquito species and suitable for safe and eco-compatible applications.
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Affiliation(s)
- Agata Negri
- Department of Biosciences, University of Milan, Milan, Italy
- Pediatric Clinical Research Center “Romeo ed Enrica Invernizzi”, University of Milan, Milan, Italy
- Italian Malaria Network, Inter University Center for Malaria Research, University of Milan, Milan, Italy
| | - Giulia Pezzali
- Department of Biosciences, University of Milan, Milan, Italy
| | - Simone Pitton
- Department of Biosciences, University of Milan, Milan, Italy
| | - Marco Piazzoni
- Department of Physics, University of Milan, Milan, Italy
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, Milan, Italy
| | | | - Giovanni Naro
- Department of Biosciences, University of Milan, Milan, Italy
| | - Paolo Gabrieli
- Department of Biosciences, University of Milan, Milan, Italy
- Pediatric Clinical Research Center “Romeo ed Enrica Invernizzi”, University of Milan, Milan, Italy
- Italian Malaria Network, Inter University Center for Malaria Research, University of Milan, Milan, Italy
| | - Giorgia Bettoni
- Department of Biosciences, University of Milan, Milan, Italy
- Pediatric Clinical Research Center “Romeo ed Enrica Invernizzi”, University of Milan, Milan, Italy
| | - Claudio Bandi
- Department of Biosciences, University of Milan, Milan, Italy
- Pediatric Clinical Research Center “Romeo ed Enrica Invernizzi”, University of Milan, Milan, Italy
- Italian Malaria Network, Inter University Center for Malaria Research, University of Milan, Milan, Italy
| | - Silvia Caccia
- Department of Biosciences, University of Milan, Milan, Italy
| | - Sara Epis
- Department of Biosciences, University of Milan, Milan, Italy
- Pediatric Clinical Research Center “Romeo ed Enrica Invernizzi”, University of Milan, Milan, Italy
- Italian Malaria Network, Inter University Center for Malaria Research, University of Milan, Milan, Italy
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Deng SQ, Li N, Yang XK, Lu HZ, Liu JH, Peng ZY, Wang LM, Zhang M, Zhang C, Chen C. Recombinant Beauveria bassiana expressing Bacillus thuringiensis toxin Cyt1Aa: a promising approach for enhancing Aedes mosquito control. Microbiol Spectr 2024; 12:e0379223. [PMID: 38809029 PMCID: PMC11218515 DOI: 10.1128/spectrum.03792-23] [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: 10/28/2023] [Accepted: 04/20/2024] [Indexed: 05/30/2024] Open
Abstract
The entomopathogenic fungus Beauveria bassiana provides an eco-friendly substitute to chemical insecticides for mosquito control. Nevertheless, its widespread application has been hindered by its comparatively slow efficacy in eliminating mosquitoes. To augment the potency of B. bassiana against Aedes mosquitoes, a novel recombinant strain, Bb-Cyt1Aa, was developed by incorporating the Bacillus thuringiensis toxin gene Cyt1Aa into B. bassiana. The virulence of Bb-Cyt1Aa was evaluated against Aedes aegypti and Aedes albopictus using insect bioassays. Compared to the wild-type (WT) strain, the median lethal time (LT50) for A. aegypti larvae infected with Bb-Cyt1Aa decreased by 33.3% at a concentration of 1 × 108 conidia/mL and by 22.2% at 1 × 107 conidia/mL. The LT50 for A. aegypti adults infected with Bb-Cyt1Aa through conidia ingestion was reduced by 37.5% at 1 × 108 conidia/mL and by 33.3% at 1 × 107 conidia/mL. Likewise, the LT50 for A. aegypti adults infected with Bb-Cyt1Aa through cuticle contact decreased by 33.3% and 30.8% at the same concentrations, respectively. Furthermore, the Bb-Cyt1Aa strain also demonstrated increased toxicity against both larval and adult A. albopictus, when compared to the WT strain. In conclusion, our study demonstrated that the expression of B. thuringiensis toxin Cyt1Aa in B. bassiana enhanced its virulence against Aedes mosquitoes. This suggests that B. bassiana expressing Cyt1Aa has potential value for use in mosquito control. IMPORTANCE Beauveria bassiana is a naturally occurring fungus that can be utilized as a bioinsecticide against mosquitoes. Cyt1Aa is a delta-endotoxin protein produced by Bacillus thuringiensis that exhibits specific and potent insecticidal activity against mosquitoes. In our study, the expression of this toxin Cyt1Aa in B. bassiana enhances the virulence of B. bassiana against Aedes aegypti and Aedes albopictus, thereby increasing their effectiveness in killing mosquitoes. This novel strain can be used alongside chemical insecticides to reduce dependence on harmful chemicals, thereby minimizing negative impacts on the environment and human health. Additionally, the potential resistance of B. bassiana against mosquitoes in the future could be overcome by acquiring novel combinations of exogenous toxin genes. The presence of B. bassiana that expresses Cyt1Aa is of significant importance in mosquito control as it enhances genetic diversity, creates novel virulent strains, and contributes to the development of safer and more sustainable methods of mosquito control.
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Affiliation(s)
- Sheng-Qun Deng
- Department of Pathogen Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
- Anhui Province Key Laboratory of Zoonoses, the Key Laboratory of Zoonoses of High Institutions in Anhui, Anhui Medical University, Hefei, China
| | - Ni Li
- Department of Pathogen Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Xu-Ke Yang
- Department of Pathogen Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
- Anhui Province Key Laboratory of Zoonoses, the Key Laboratory of Zoonoses of High Institutions in Anhui, Anhui Medical University, Hefei, China
| | - Hong-Zheng Lu
- Department of Pathogen Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Jia-Hua Liu
- Department of Pathogen Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Zhe-Yu Peng
- Department of Pathogen Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Lin-Min Wang
- Department of Pathogen Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Mao Zhang
- Department of Pathogen Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
- Anhui Province Key Laboratory of Zoonoses, the Key Laboratory of Zoonoses of High Institutions in Anhui, Anhui Medical University, Hefei, China
| | - Chao Zhang
- Department of Pathogen Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
- Anhui Province Key Laboratory of Zoonoses, the Key Laboratory of Zoonoses of High Institutions in Anhui, Anhui Medical University, Hefei, China
| | - Chen Chen
- Anhui Province Key Laboratory of Zoonoses, the Key Laboratory of Zoonoses of High Institutions in Anhui, Anhui Medical University, Hefei, China
- Department of Microbiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
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10
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Tarsitano J, Bockor SS, Palomino MM, Fina Martin J, Ruzal SM, Allievi MC. [Deficiency in N-acetylglucosamine transport affects the sporulation process and increases the hemolytic activity of the S-layer protein in Lysinibacillus sphaericus ASB13052]. Rev Argent Microbiol 2024; 56:232-240. [PMID: 39218718 DOI: 10.1016/j.ram.2024.05.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 05/09/2024] [Accepted: 05/28/2024] [Indexed: 09/04/2024] Open
Abstract
Lysinibacillus sphaericus is a bacterium that, along with Bacillus thuringiensis var. israelensis, is considered the best biological insecticide for controlling mosquito larvae and an eco-friendly alternative to chemical insecticides. It depends on peptidic molecules such as N-acetylglucosamine to obtain carbon sources and possesses a phosphotransferase system (PTS) for their incorporation. Some strains carry S-layer proteins, whose involvement in metal retention and larvicidal activity against disease-carrying mosquitoes has been demonstrated. Alterations in the amino sugar incorporation system could affect the protein profile and functionality. Strain ASB13052 and the isogenic mutant in the ptsH gene, which is predominant in the PTS signaling pathway, were used in this study. For the first time, the presence of N-glycosylated S-layer proteins was confirmed in both strains, with a variation in their molecular weight pattern depending on the growth phase. In the exponential phase, an S-layer protein greater than 130 kDa was found in the ptsH mutant, which was absent in the wild-type strain. The mutant strain exhibited altered and incomplete low quality sporulation processes. Hemolysis analysis, associated with larvicidal activity, showed that the ptsH mutant has higher lytic efficiency, correlating with the high molecular weight protein. The results allow us to propose the potential effects that arise as a result of the absence of amino sugar transport on hemolytic activity, S-layer isoforms, and the role of N-acetylglucosamine in larvicidal activity.
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Affiliation(s)
- Julián Tarsitano
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Ciudad Autónoma de Buenos Aires, Argentina
| | - Sabrina Sol Bockor
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires - Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN) - CONICET, Ciudad Universitaria, Ciudad Autónoma de Buenos Aires, Argentina
| | - María Mercedes Palomino
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires - Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN) - CONICET, Ciudad Universitaria, Ciudad Autónoma de Buenos Aires, Argentina
| | - Joaquina Fina Martin
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires - Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN) - CONICET, Ciudad Universitaria, Ciudad Autónoma de Buenos Aires, Argentina
| | - Sandra Mónica Ruzal
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires - Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN) - CONICET, Ciudad Universitaria, Ciudad Autónoma de Buenos Aires, Argentina
| | - Mariana Claudia Allievi
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires - Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN) - CONICET, Ciudad Universitaria, Ciudad Autónoma de Buenos Aires, Argentina.
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11
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Ulug D, Touray M, Hazal Gulsen S, Cimen H, Hazir C, Bode HB, Hazir S. A taste of a toxin paradise: Xenorhabdus and Photorhabdus bacterial secondary metabolites against Aedes aegypti larvae and eggs. J Invertebr Pathol 2024; 205:108126. [PMID: 38734162 DOI: 10.1016/j.jip.2024.108126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 04/30/2024] [Accepted: 05/07/2024] [Indexed: 05/13/2024]
Abstract
Aedes-transmitted arboviral infections such as Dengue, Yellow Fever, Zika and Chikungunya are increasing public health problems. Xenorhabdus and Photorhabdus bacteria are promising sources of effective compounds with important biological activities. This study investigated the effects of cell-free supernatants of X. szentirmaii, X. cabanillasii and P. kayaii against Ae. aegypti eggs and larvae and identified the bioactive larvicidal compound in X. szentirmaii using The EasyPACId method. Among the three tested bacterial species, X. cabanillasii exhibited the highest (96%) egg hatching inhibition and larvicidal activity (100% mortality), whereas P. kayaii was the least effective species in our study. EasyPACId method revealed that bioactive larvicidal compound in the bacterial supernatant was fabclavine. Fabclavines obtained from promoter exchange mutants of different bacterial species such as X. cabanillasii, X. budapestensis, X. indica, X. szentirmaii, X. hominckii and X. stockiae were effective against mosquito larvae. Results show that these bacterial metabolites have potential to be used in integrated pest management (IPM) programmes of mosquitoes.
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Affiliation(s)
- Derya Ulug
- Department of Biology, Faculty of Science, Aydin Adnan Menderes University, 09100, Aydin, Türkiye.
| | - Mustapha Touray
- Department of Biology, Faculty of Science, Aydin Adnan Menderes University, 09100, Aydin, Türkiye
| | - Sebnem Hazal Gulsen
- Department of Plant and Animal Production, Kocarli Vocational School, Aydin Adnan Menderes University, 09100 Aydin, Türkiye
| | - Harun Cimen
- Recombinant DNA and Recombinant Protein Application and Research Center, Aydin Adnan Menderes University, 09100, Aydin, Türkiye
| | - Canan Hazir
- Aydin Health Services Vocational School, Adnan Menderes University, 09100 Aydin, Türkiye
| | - Helge B Bode
- Max-Planck-Institute for Terrestrial Microbiology, Department of Natural Products in Organismic Interactions, 35043 Marburg, Germany; Molekulare Biotechnologie, Fachbereich Biowissenschaften, Goethe Universität Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany; Center for Synthetic Microbiology, Phillips University Marburg, 35043 Marburg, Germany; Department of Chemistry, Phillips University Marburg, 35043 Marburg, Germany; Senckenberg Gesellschaft für Naturforschung, Frankfurt am Main, 60325, Germany
| | - Selcuk Hazir
- Department of Biology, Faculty of Science, Aydin Adnan Menderes University, 09100, Aydin, Türkiye
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12
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Pacheco S, Gallegos AS, Peláez-Aguilar ÁE, Sánchez J, Gómez I, Soberón M, Bravo A. CRISPR-Cas9 knockout of membrane-bound alkaline phosphatase or cadherin does not confer resistance to Cry toxins in Aedes aegypti. PLoS Negl Trop Dis 2024; 18:e0012256. [PMID: 38870209 PMCID: PMC11207138 DOI: 10.1371/journal.pntd.0012256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 06/26/2024] [Accepted: 05/30/2024] [Indexed: 06/15/2024] Open
Abstract
The Aedes aegypti cadherin-like protein (Aae-Cad) and the membrane-bound alkaline phosphatase (Aae-mALP) are membrane proteins identified as putative receptors for the larvicidal Cry toxins produced by Bacillus thuringiensis subsp. israelensis bacteria. Cry toxins are the most used toxins in the control of different agricultural pest and mosquitos. Despite the relevance of Aae-Cad and Aae-mALP as possible toxin-receptors in mosquitoes, previous efforts to establish a clear functional connection among them and Cry toxins activity have been relatively limited. In this study, we used CRISPR-Cas9 to generate knockout (KO) mutations of Aae-Cad and Aae-mALP. The Aae-mALP KO was successfully generated, in contrast to the Aae-Cad KO which was obtained only in females. The female-linked genotype was due to the proximity of aae-cad gene to the sex-determining loci (M:m). Both A. aegypti KO mutant populations were viable and their insect-development was not affected, although a tendency on lower egg hatching rate was observed. Bioassays were performed to assess the effects of these KO mutations on the susceptibility of A. aegypti to Cry toxins, showing that the Aae-Cad female KO or Aae-mALP KO mutations did not significantly alter the susceptibility of A. aegypti larvae to the mosquitocidal Cry toxins, including Cry11Aa, Cry11Ba, Cry4Ba, and Cry4Aa. These findings suggest that besides the potential participation of Aae-Cad and Aae-mALP as Cry toxin receptors in A. aegypti, additional midgut membrane proteins are involved in the mode of action of these insecticidal toxins.
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Affiliation(s)
- Sabino Pacheco
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, Mexico
| | - Adrián S. Gallegos
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, Mexico
| | - Ángel E. Peláez-Aguilar
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, Mexico
| | - Jorge Sánchez
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, Mexico
| | - Isabel Gómez
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, Mexico
| | - Mario Soberón
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, Mexico
| | - Alejandra Bravo
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, Mexico
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13
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Tia JPB, Tchicaya ESF, Zahouli JZB, Ouattara AF, Vavassori L, Assamoi JB, Small G, Koudou BG. Combined use of long-lasting insecticidal nets and Bacillus thuringiensis israelensis larviciding, a promising integrated approach against malaria transmission in northern Côte d'Ivoire. Malar J 2024; 23:168. [PMID: 38812003 PMCID: PMC11137964 DOI: 10.1186/s12936-024-04953-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 04/15/2024] [Indexed: 05/31/2024] Open
Abstract
BACKGROUND The recent reduction in malaria burden in Côte d'Ivoire is largely attributable to the use of long-lasting insecticidal nets (LLINs). However, this progress is threatened by insecticide resistance and behavioral changes in Anopheles gambiae sensu lato (s.l.) populations and residual malaria transmission, and complementary tools are required. Thus, this study aimed to assess the efficacy of the combined use of LLINs and Bacillus thuringiensis israelensis (Bti), in comparison with LLINs. METHODS This study was conducted in the health district of Korhogo, northern Côte d'Ivoire, within two study arms (LLIN + Bti arm and LLIN-only arm) from March 2019 to February 2020. In the LLIN + Bti arm, Anopheles larval habitats were treated every fortnight with Bti in addition to the use of LLINs. Mosquito larvae and adults were sampled and identified morphologically to genus and species using standard methods. The members of the An. gambiae complex were determined using a polymerase chain reaction technique. Plasmodium infection in An. gambiae s.l. and malaria incidence in local people was also assessed. RESULTS Overall, Anopheles spp. larval density was lower in the LLIN + Bti arm 0.61 [95% CI 0.41-0.81] larva/dip (l/dip) compared with the LLIN-only arm 3.97 [95% CI 3.56-4.38] l/dip (RR = 6.50; 95% CI 5.81-7.29; P < 0.001). The overall biting rate of An. gambiae s.l. was 0.59 [95% CI 0.43-0.75] biting/person/night in the LLIN + Bti arm against 2.97 [95% CI 2.02-3.93] biting/person/night in LLIN-only arm (P < 0.001). Anopheles gambiae s.l. was predominantly identified as An. gambiae sensu stricto (s.s.) (95.1%, n = 293), followed by Anopheles coluzzii (4.9%; n = 15). The human-blood index was 80.5% (n = 389) in study area. EIR was 1.36 infected bites/person/year (ib/p/y) in the LLIN + Bti arm against 47.71 ib/p/y in the LLIN-only arm. Malaria incidence dramatically declined from 291.8‰ (n = 765) to 111.4‰ (n = 292) in LLIN + Bti arm (P < 0.001). CONCLUSIONS The combined use of LLINs with Bti significantly reduced the incidence of malaria. The LLINs and Bti duo could be a promising integrated approach for effective vector control of An. gambiae for elimination of malaria.
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Affiliation(s)
- Jean-Philippe B Tia
- Université Nangui Abrogoua, Abidjan, Côte d'Ivoire.
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire.
| | - Emile S F Tchicaya
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire
- Université Péléforo Gon Coulibaly, Korhogo, Côte d'Ivoire
| | - Julien Z B Zahouli
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire
- Centre d'Entomologie Médicale et Vétérinaire, Université Alassane Ouattara, Bouaké, Côte d'Ivoire
| | - Allassane F Ouattara
- Université Nangui Abrogoua, Abidjan, Côte d'Ivoire
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire
| | - Laura Vavassori
- University of Basel, Basel, Switzerland
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland
| | | | - Graham Small
- Innovative Vector Control Consortium, Pembroke Place, Liverpool, L3 5QA, UK
| | - Benjamin G Koudou
- Université Nangui Abrogoua, Abidjan, Côte d'Ivoire
- Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire
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14
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Silva JRDA, de Oliveira AA, França LP, da Cruz JD, Amaral ACF. Exploring the Larvicidal and Adulticidal Activity against Aedes aegypti of Essential Oil from Bocageopsis multiflora. Molecules 2024; 29:2240. [PMID: 38792102 PMCID: PMC11124082 DOI: 10.3390/molecules29102240] [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: 04/14/2024] [Revised: 05/01/2024] [Accepted: 05/04/2024] [Indexed: 05/26/2024] Open
Abstract
This study investigates the chemical composition of the essential oil obtained from the leaves of Bocageopsis multiflora (Mart.) R.E.Fr (Annonaceae), examining its effectiveness in combating both the larvae and adult forms of Aedes aegypti mosquitoes. Additionally, for a deeper understanding of the insecticidal activity, toxicity properties and molecular docking calculations were conducted using the main compounds of this essential oil. GC/MS analysis revealed the presence of 26 constituents, representing 95.2% of the essential oil, with the major components identified as the sesquiterpenes α-selinene, β-selinene, and β-elemene. Larvicidal assays demonstrated potent activity of this essential oil with significant LC50 values of 40.8 and 39.4 μg/mL at 24 and 48 h, respectively. Adulticidal assessments highlighted strong efficacy with LC50 of 12.5 µg/mL. Molecular docking analysis identified optimal interaction activities of α-selinene and β-selinene with key Aedes proteins. The in silico studies comparing synthetic insecticides with the major sesquiterpenes of the essential oil revealed that β-selinene exhibited a significantly higher binding affinity compared to the other two sesquiterpenes. Also, ADMET studies of the three main sesquiterpenes indicated acceptable drug-like properties. In these findings, safety evaluations showed low toxicity and skin sensitization for the main sesquiterpenes, contrasting with commercial synthetic insecticides. Therefore, in silico analyses suggest promising interactions with Aedes proteins, indicating its potential as an effective alternative to conventional insecticides These results show the larvicidal and adulticidal potential of the essential oil from Bocageopsis multiflora against Aedes aegypti, supported by its predominant constituents, α-selinene, β-selinene and β-elemene.
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Affiliation(s)
- Jefferson Rocha de Andrade Silva
- Laboratório de Cromatografia, Departamento de Química, Instituto de Ciências Exatas, Universidade Federal do Amazonas, Manaus 69077-000, Brazil; (A.A.d.O.); (L.P.F.)
| | - Aimêe Almeida de Oliveira
- Laboratório de Cromatografia, Departamento de Química, Instituto de Ciências Exatas, Universidade Federal do Amazonas, Manaus 69077-000, Brazil; (A.A.d.O.); (L.P.F.)
| | - Leandro Pereira França
- Laboratório de Cromatografia, Departamento de Química, Instituto de Ciências Exatas, Universidade Federal do Amazonas, Manaus 69077-000, Brazil; (A.A.d.O.); (L.P.F.)
| | - Jefferson Diocesano da Cruz
- Laboratório de Plantas Medicinais e Derivados, Farmanguinhos, Fundação Oswaldo Cruz, Rio de Janeiro 21041-250, Brazil;
| | - Ana Claudia Fernandes Amaral
- Laboratório de Plantas Medicinais e Derivados, Farmanguinhos, Fundação Oswaldo Cruz, Rio de Janeiro 21041-250, Brazil;
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15
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de Oliveira AC, Simões RC, da Silva FMA, Sá ISC, da Costa MLL, Nunomura SM, Nunomura RCS, Roque RA. Essential oil and fenchone extracted from Tetradenia riparia (Hochstetter.) Codd (Lamiaceae) induce oxidative stress in Culex quinquefasciatus larvae (Diptera: Culicidae) without causing lethal effects on non-target animals. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:32998-33010. [PMID: 38671268 DOI: 10.1007/s11356-024-33440-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Accepted: 04/19/2024] [Indexed: 04/28/2024]
Abstract
We investigated the larvicidal activity of the essential oil (EO) from Tetradenia riparia and its majority compound fenchone for controlling Culex quinquefasciatus larvae, focusing on reactive oxygen and nitrogen species (RONS), catalase (CAT), glutathione S-transferase (GST), acetylcholinesterase (AChE) activities, and total thiol content as oxidative stress indicators. Moreover, the lethal effect of EO and fenchone was evaluated against Anisops bouvieri, Diplonychus indicus, Danio rerio, and Paracheirodon axelrodi. The EO and fenchone (5 to 25 µg/mL) showed larvicidal activity (LC50 from 16.05 to 18.94 µg/mL), followed by an overproduction of RONS, and changes in the activity of CAT, GST, AChE, and total thiol content. The Kaplan-Meier followed by Log-rank (Mantel-Cox) analyses showed a 100% survival rate for A. bouvieri, D. indicus, D. rerio, and P. axelrodi when exposed to EO and fenchone (262.6 and 302.60 µg/mL), while α-cypermethrin (0.25 µg/mL) was extremely toxic to these non-target animals, causing 100% of death. These findings emphasize that the EO from T. riparia and fenchone serve as suitable larvicides for controlling C. quinquefasciatus larvae, without imposing lethal effects on the non-target animals investigated.
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Affiliation(s)
- André C de Oliveira
- Central Analítica, Centro de Apoio Multidisciplinar, Universidade Federal Do Amazonas, Manaus, Amazonas, 69080-900, Brazil.
- Laboratório de Controle Biológico E Biotecnologia da Malária E da Dengue, Coordenação Sociedade, Ambiente E Saúde, Instituto Nacional de Pesquisas da Amazônia, Manaus, Amazonas, 69067-375, Brazil.
| | - Rejane C Simões
- Fundação de Vigilância Em Saúde Do Amazonas, Dra Rosemary Costa Pinto, Manaus, Amazonas, 69093-018, Brazil
| | - Felipe M A da Silva
- Central Analítica, Centro de Apoio Multidisciplinar, Universidade Federal Do Amazonas, Manaus, Amazonas, 69080-900, Brazil
| | - Ingrity S C Sá
- Central Analítica, Centro de Apoio Multidisciplinar, Universidade Federal Do Amazonas, Manaus, Amazonas, 69080-900, Brazil
| | - Maria L L da Costa
- Laboratório de Controle Biológico E Biotecnologia da Malária E da Dengue, Coordenação Sociedade, Ambiente E Saúde, Instituto Nacional de Pesquisas da Amazônia, Manaus, Amazonas, 69067-375, Brazil
| | - Sergio M Nunomura
- Laboratório de Princípios Ativos da Amazônia, Coordenação de Tecnologia E Inovação, Instituto Nacional de Pesquisas da Amazônia, Manaus, Amazonas, 69067-375, Brazil
| | - Rita C S Nunomura
- Laboratório de Controle Biológico E Biotecnologia da Malária E da Dengue, Coordenação Sociedade, Ambiente E Saúde, Instituto Nacional de Pesquisas da Amazônia, Manaus, Amazonas, 69067-375, Brazil
| | - Rosemary A Roque
- Laboratório de Controle Biológico E Biotecnologia da Malária E da Dengue, Coordenação Sociedade, Ambiente E Saúde, Instituto Nacional de Pesquisas da Amazônia, Manaus, Amazonas, 69067-375, Brazil
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16
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Guzmán LE, Wijetunge AN, Riske BF, Massani BB, Riehle MA, Jewett JC. Chemical Probes to Interrogate the Extreme Environment of Mosquito Larval Guts. J Am Chem Soc 2024; 146:8480-8485. [PMID: 38484471 PMCID: PMC11077398 DOI: 10.1021/jacs.3c14598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2024]
Abstract
Mosquito control methods are vital to curtail the spread of life-threatening illnesses, such as dengue fever, malaria, and yellow fever. Vector control technologies must be selective to minimize deleterious effects on our ecosystem. Successful methods that control mosquito larva populations utilize the uniquely high alkaline nature of the midgut. Here, we present novel protected triazabutadienes (pTBD) that are deprotected under basic conditions of the larval midgut, releasing an aryl diazonium ion (ADI) that results in protein modification. The probes contain a bioorthogonal terminal alkyne handle, enabling a selective Cu-click reaction with an azidofluorophore for quantification by SDS PAGE and visualization using fluorescence microscopy. A control TBD, unable to release an ADI, did not label the midgut. We envision our chemical probes will aid in the development of new selective mosquito control methods, thus preventing the spread of mosquito-borne illnesses with minimal impact on other organisms in the ecosystem.
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Affiliation(s)
- Lindsay E. Guzmán
- Department of Chemistry & Biochemistry, University of Arizona, Tucson, AZ 85721, United States
| | - Anjalee N. Wijetunge
- Department of Chemistry & Biochemistry, University of Arizona, Tucson, AZ 85721, United States
| | - Brendan F. Riske
- Department of Entomology, University of Arizona, Tucson, AZ 85721, United States
| | - Brooke B. Massani
- Department of Chemistry & Biochemistry, University of Arizona, Tucson, AZ 85721, United States
| | - Michael A. Riehle
- Department of Entomology, University of Arizona, Tucson, AZ 85721, United States
| | - John C. Jewett
- Department of Chemistry & Biochemistry, University of Arizona, Tucson, AZ 85721, United States
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17
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Miranda LS, Rudd SR, Mena O, Hudspeth PE, Barboza-Corona JE, Park HW, Bideshi DK. The Perpetual Vector Mosquito Threat and Its Eco-Friendly Nemeses. BIOLOGY 2024; 13:182. [PMID: 38534451 DOI: 10.3390/biology13030182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2024] [Revised: 03/06/2024] [Accepted: 03/08/2024] [Indexed: 03/28/2024]
Abstract
Mosquitoes are the most notorious arthropod vectors of viral and parasitic diseases for which approximately half the world's population, ~4,000,000,000, is at risk. Integrated pest management programs (IPMPs) have achieved some success in mitigating the regional transmission and persistence of these diseases. However, as many vector-borne diseases remain pervasive, it is obvious that IPMP successes have not been absolute in eradicating the threat imposed by mosquitoes. Moreover, the expanding mosquito geographic ranges caused by factors related to climate change and globalization (travel, trade, and migration), and the evolution of resistance to synthetic pesticides, present ongoing challenges to reducing or eliminating the local and global burden of these diseases, especially in economically and medically disadvantaged societies. Abatement strategies include the control of vector populations with synthetic pesticides and eco-friendly technologies. These "green" technologies include SIT, IIT, RIDL, CRISPR/Cas9 gene drive, and biological control that specifically targets the aquatic larval stages of mosquitoes. Regarding the latter, the most effective continues to be the widespread use of Lysinibacillus sphaericus (Ls) and Bacillus thuringiensis subsp. israelensis (Bti). Here, we present a review of the health issues elicited by vector mosquitoes, control strategies, and lastly, focus on the biology of Ls and Bti, with an emphasis on the latter, to which no resistance has been observed in the field.
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Affiliation(s)
- Leticia Silva Miranda
- Graduate Program in Biomedical Sciences, Department of Biological Sciences, California Baptist University, Riverside, CA 92504, USA
| | - Sarah Renee Rudd
- Graduate Program in Biomedical Sciences, Department of Biological Sciences, California Baptist University, Riverside, CA 92504, USA
- Integrated Biomedical Graduate Studies, and School of Medicine, Loma Linda University, Loma Linda, CA 92350, USA
| | - Oscar Mena
- Undergraduate Program in Biomedical Sciences, Department of Biological Sciences, California Baptist University, Riverside, CA 92504, USA
| | - Piper Eden Hudspeth
- Undergraduate Program in Biomedical Sciences, Department of Biological Sciences, California Baptist University, Riverside, CA 92504, USA
| | - José E Barboza-Corona
- Departmento de Alimentos, Posgrado en Biociencias, Universidad de Guanajuato Campus Irapuato-Salamanca, Irapuato 36500, Guanajuato, Mexico
| | - Hyun-Woo Park
- Graduate Program in Biomedical Sciences, Department of Biological Sciences, California Baptist University, Riverside, CA 92504, USA
- Undergraduate Program in Biomedical Sciences, Department of Biological Sciences, California Baptist University, Riverside, CA 92504, USA
| | - Dennis Ken Bideshi
- Graduate Program in Biomedical Sciences, Department of Biological Sciences, California Baptist University, Riverside, CA 92504, USA
- Undergraduate Program in Biomedical Sciences, Department of Biological Sciences, California Baptist University, Riverside, CA 92504, USA
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Wolstenholme AJ, Andersen EC, Choudhary S, Ebner F, Hartmann S, Holden-Dye L, Kashyap SS, Krücken J, Martin RJ, Midha A, Nejsum P, Neveu C, Robertson AP, von Samson-Himmelstjerna G, Walker R, Wang J, Whitehead BJ, Williams PDE. Getting around the roundworms: Identifying knowledge gaps and research priorities for the ascarids. ADVANCES IN PARASITOLOGY 2024; 123:51-123. [PMID: 38448148 PMCID: PMC11143470 DOI: 10.1016/bs.apar.2023.12.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/08/2024]
Abstract
The ascarids are a large group of parasitic nematodes that infect a wide range of animal species. In humans, they cause neglected diseases of poverty; many animal parasites also cause zoonotic infections in people. Control measures include hygiene and anthelmintic treatments, but they are not always appropriate or effective and this creates a continuing need to search for better ways to reduce the human, welfare and economic costs of these infections. To this end, Le Studium Institute of Advanced Studies organized a two-day conference to identify major gaps in our understanding of ascarid parasites with a view to setting research priorities that would allow for improved control. The participants identified several key areas for future focus, comprising of advances in genomic analysis and the use of model organisms, especially Caenorhabditis elegans, a more thorough appreciation of the complexity of host-parasite (and parasite-parasite) communications, a search for novel anthelmintic drugs and the development of effective vaccines. The participants agreed to try and maintain informal links in the future that could form the basis for collaborative projects, and to co-operate to organize future meetings and workshops to promote ascarid research.
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Affiliation(s)
- Adrian J Wolstenholme
- Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (INRAE), Université de Tours, ISP, Nouzilly, France.
| | - Erik C Andersen
- Department of Biology, Johns Hopkins University, Baltimore, MD, United States
| | - Shivani Choudhary
- Department of Biomedical Sciences, Iowa State University, Ames, IA, United States
| | - Friederike Ebner
- Department of Molecular Life Sciences, School of Life Sciences, Technische Universität München, Freising, Germany
| | - Susanne Hartmann
- Institute for Immunology, Freie Universität Berlin, Berlin, Germany
| | - Lindy Holden-Dye
- School of Biological Sciences, University of Southampton, Southampton, United Kingdom
| | - Sudhanva S Kashyap
- Department of Biomedical Sciences, Iowa State University, Ames, IA, United States
| | - Jürgen Krücken
- Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
| | - Richard J Martin
- Department of Biomedical Sciences, Iowa State University, Ames, IA, United States
| | - Ankur Midha
- Institute for Immunology, Freie Universität Berlin, Berlin, Germany
| | - Peter Nejsum
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Cedric Neveu
- Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (INRAE), Université de Tours, ISP, Nouzilly, France
| | - Alan P Robertson
- Department of Biomedical Sciences, Iowa State University, Ames, IA, United States
| | | | - Robert Walker
- School of Biological Sciences, University of Southampton, Southampton, United Kingdom
| | - Jianbin Wang
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, United States
| | | | - Paul D E Williams
- Department of Biomedical Sciences, Iowa State University, Ames, IA, United States
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19
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Nelson IE, Baker KA, Faraji A, White GS, Bibbs CS. Diuresis and α-glucosidase inhibition by erythritol in Aedes aegypti (Diptera: Culicidae) and viability for efficacy against mosquitoes. Parasit Vectors 2024; 17:76. [PMID: 38378683 PMCID: PMC10880232 DOI: 10.1186/s13071-024-06169-w] [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: 12/14/2023] [Accepted: 01/29/2024] [Indexed: 02/22/2024] Open
Abstract
BACKGROUND Sugar alcohols, such as erythritol, are low-impact candidates for attractive toxic sugar baits (ATSB) to kill mosquitoes. To determine whether erythritol has a viable future in ATSB formulations, a suite of assays was conducted to diagnose toxicity mechanisms and starvation effects on mortality in Aedes aegypti (L.) as a model system. METHODS We measured general carbohydrate load, glucosidase levels, and free glucose in intoxicated adult mosquitoes to observe whether sugar digestion was impaired. We assayed the effects of sugar combinations with erythritol on larvae and adults. To measure erythritol effects when mosquitoes were not resource-deprived, additional assays manipulated the prior starvation status. RESULTS Up to 50,000 ppm of erythritol in water had no effect on larvae within 72 h, but an ammonia spike indicated diuresis in larvae as early as 4 h (F8,44 = 22.50, P < 0.0001) after sucrose/erythritol combinations were added. Adult consumption of erythritol was diuretic regardless of the sugar pairing, while sucrose and erythritol together generated above 80% mortality (F2,273 = 33.30, P < 0.0001) alongside triple the normal excretion (F5,78 = 26.80, P < 0.0004). Glucose and fructose paired individually with erythritol had less mortality, but still double the fecal excretion. When ingesting erythritol-laced meals, less sugar was detected in mosquitoes as compared to after sucrose meals (χ2 = 12.54, df = 1, P = 0.0004). CONCLUSIONS Data showed that erythritol is a linear competitive inhibitor of α-glucosidase, marking it as a novel class of insecticide in the current research climate. However, the efficacy on larvae was null and not persistent in adult mosquitoes when compared across various starvation levels. Despite significant diuresis, the combined effects from erythritol are not acute enough for vector control programs considering ATSB against mosquitoes.
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Affiliation(s)
- Irvane E Nelson
- Salt Lake City Mosquito Abatement District, 2215 North 2200 West, Salt Lake City, UT, 84116, USA
- College of Science, Science Research Initiative (SRI), University of Utah, 1390 Presidents Circle, Crocker Science Center, rm 310, Salt Lake City, UT, 84112, USA
| | - Kobi A Baker
- Salt Lake City Mosquito Abatement District, 2215 North 2200 West, Salt Lake City, UT, 84116, USA
| | - Ary Faraji
- Salt Lake City Mosquito Abatement District, 2215 North 2200 West, Salt Lake City, UT, 84116, USA
| | - Gregory S White
- Salt Lake City Mosquito Abatement District, 2215 North 2200 West, Salt Lake City, UT, 84116, USA
| | - Christopher S Bibbs
- Salt Lake City Mosquito Abatement District, 2215 North 2200 West, Salt Lake City, UT, 84116, USA.
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20
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Vaselek S, Sarac BE, Uzunkaya AD, Yilmaz A, Karaaslan C, Alten B. Identification of Ochrobactrum as a bacteria with transstadial transmission and potential for application in paratransgenic control of leishmaniasis. Parasitol Res 2024; 123:82. [PMID: 38175278 DOI: 10.1007/s00436-023-08087-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Accepted: 12/05/2023] [Indexed: 01/05/2024]
Abstract
Leishmaniasis is a zoonotic vector-borne disease with worldwide distribution. All current approaches in leishmaniasis control or development of vaccines/cures showed only limited success. Recently, paratransgenesis has been marked as a promising strategy for leishmaniasis control. Thus, the investigations of the gut microbial content of sand flies have gained popularity. Gut microbial composition of the laboratory colony of Phlebotomus papatasi was investigated via microbial culturomics approach which refers to the combination of multiple culture conditions and different selective and/or enriched culture mediums, followed by 16S rDNA sequencing. Investigations were conducted on three offspring generations, with six samplings of immature stages (four larval samplings, one pre-pupa, one pupa) and samplings of adults before and after blood feeding. The aim was to determine if microbiome changes during the sand fly development and to identify bacteria with transstadial potential. The presence of 8 bacterial taxa (Bacillus sp., Terribacillus sp., Staphylococcus sp., Alcaligenes sp., Microbacterium sp., Leucobacter sp., Ochrobactrum sp. and Enterobacter sp.), 2 fungi (Fusarium sp. and Acremonium sp.) and 1 yeast (Candida sp.) were recorded. Gram-positive bacteria were more diverse, but gram-negative bacteria were more abundant. All taxa were recorded among immature stage samples, while only one bacterium was detected in adults. Microbial diversity among larval samples was stable, with a steady decrease in pre-pupa and pupa, resulting in the survival of only Ochrobactrum sp. in adults. Abundance of microbes was higher when larvae were actively feeding, with a gradual decrease after larvae stopped feeding and commenced pupation. Ochrobactrum sp. is the bacteria with transstadial potential, worthy of future in-depth analysis for the application in paratransgenic approach for the control of Leishmania sp.
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Affiliation(s)
- Slavica Vaselek
- Hacettepe University, Faculty of Science, Department of Biology, Ecology Section, Ankara, Türkiye.
| | - Basak Ezgi Sarac
- Hacettepe University, Faculty of Science, Department of Biology, Molecular Biology Section, Ankara, Türkiye
| | - Ali Doruk Uzunkaya
- Hacettepe University, Faculty of Science, Department of Biology, Molecular Biology Section, Ankara, Türkiye
| | - Ayda Yilmaz
- Hacettepe University, Faculty of Science, Department of Biology, Ecology Section, Ankara, Türkiye
| | - Cagatay Karaaslan
- Hacettepe University, Faculty of Science, Department of Biology, Molecular Biology Section, Ankara, Türkiye
| | - Bulent Alten
- Hacettepe University, Faculty of Science, Department of Biology, Ecology Section, Ankara, Türkiye
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21
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Guo Q, Li W, Niu Y, Dai X, Chen L. Culex quinquefasciatus membrane-bound alkaline phosphatase is a putative receptor for Lysinibacillus sphaericus Tpp49Aa1 toxin. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2024; 164:104044. [PMID: 38036275 DOI: 10.1016/j.ibmb.2023.104044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Revised: 11/22/2023] [Accepted: 11/23/2023] [Indexed: 12/02/2023]
Abstract
The binary toxin Cry48Aa1/Tpp49Aa1 produced by Lysinibacillus sphaericus exhibits potent toxicity against Culicidae larvae. Both Cry48Aa1 and Tpp49Aa1 toxins are crucial for binding to the toxin receptor in Culex quinquefasciatus larvae, albeit with different binding sites. Previous studies have identified Glu71, a membrane-bound α-glucosidase, as a putative binding protein for the Cry48Aa1 toxin, involved in the Cry48Aa1/Tpp49Aa1 toxicity. In this study, we employed pulldown assays to identify a group of Tpp49Aa1-binding proteins from C. quinquefasciatus solubilized midgut brush-border membrane proteins (BBMFs). RNA interference assays revealed that the silencing of an alkaline phosphatase gene (referred to as ALP1263) in C. quinquefasciatus resulted in a significant reduction in larval mortality upon exposure to Cry48Aa1/Tpp49Aa1 toxin in vivo. Furthermore, the ALP1263 protein exhibited specific and high-affinity binding to the Tpp49Aa1 toxin, with a dissociation constant (Kd) of approximately 57.3 nM. The dot blot analysis demonstrated that Tpp49Aa1 C-terminal region was essential for its interaction with the ALP1263 protein. In summary, our findings establish ALP1263 as a functional receptor for Tpp49Aa1 and emphasize its role in the toxicity of Cry48Aa1/Tpp49Aa1.
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Affiliation(s)
- Qingyun Guo
- College of Life Sciences, Gannan Normal University, Ganzhou City, Jiangxi Province, 341000, PR China.
| | - Wei Li
- College of Life Sciences, Gannan Normal University, Ganzhou City, Jiangxi Province, 341000, PR China
| | - Yingchao Niu
- College of Life Sciences, Gannan Normal University, Ganzhou City, Jiangxi Province, 341000, PR China
| | - Xiaohua Dai
- College of Life Sciences, Gannan Normal University, Ganzhou City, Jiangxi Province, 341000, PR China
| | - Lin Chen
- College of Life Sciences, Gannan Normal University, Ganzhou City, Jiangxi Province, 341000, PR China
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22
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Guzmán LE, Wijetunge AN, Riske BF, Massani BB, Riehle MA, Jewett JC. Chemical probes to interrogate the extreme environment of mosquito larval guts. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.27.573438. [PMID: 38234773 PMCID: PMC10793467 DOI: 10.1101/2023.12.27.573438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
Mosquito control methods are vital for the spread of life-threatening illnesses such as dengue fever, malaria, and yellow fever. Vector control technologies must be selective to minimize deleterious effects to our ecosystem. Successful methods that control mosquito larva populations utilize the uniquely high alkaline nature of the midgut. Here, we present novel protected triazabutadienes (pTBD) which are deprotected under basic conditions of the larval midgut, releasing an aryl diazonium ion (ADI) that results in protein modification. The probes contain a bioorthogonal terminal alkyne handle, enabling a selective Cu-click reaction with an azido-fluorophore for quantification by SDS PAGE and visualization using fluorescence microscopy. A control TBD, unable to release an ADI, did not label the midgut. We envision our chemical probes will aid in the development of new selective mosquito control methods thus preventing the spread of mosquito-borne illnesses with minimal impact on other organisms in the ecosystem.
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23
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Rezende TMT, Menezes HSG, Rezende AM, Cavalcanti MP, Silva YMG, de-Melo-Neto OP, Romão TP, Silva-Filha MHNL. Culex quinquefasciatus Resistant to the Binary Toxin from Lysinibacillus sphaericus Displays a Consistent Downregulation of Pantetheinase Transcripts. Biomolecules 2023; 14:33. [PMID: 38254633 PMCID: PMC10813629 DOI: 10.3390/biom14010033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 12/07/2023] [Accepted: 12/11/2023] [Indexed: 01/24/2024] Open
Abstract
Culex quinquefasciatus resistance to the binary (Bin) toxin, the major larvicidal component from Lysinibacillus sphaericus, is associated with mutations in the cqm1 gene, encoding the Bin-toxin receptor. Downregulation of the cqm1 transcript was found in the transcriptome of larvae resistant to the L. sphaericus IAB59 strain, which produces both the Bin toxin and a second binary toxin, Cry48Aa/Cry49Aa. Here, we investigated the transcription profiles of two other mosquito colonies having Bin resistance only. These confirmed the cqm1 downregulation and identified transcripts encoding the enzyme pantetheinase as the most downregulated mRNAs in both resistant colonies. Further quantification of these transcripts reinforced their strong downregulation in Bin-resistant larvae. Multiple genes were found encoding this enzyme in Cx. quinquefasciatus and a recombinant pantetheinase was then expressed in Escherichia coli and Sf9 cells, with its presence assessed in the midgut brush border membrane of susceptible larvae. The pantetheinase was expressed as a ~70 kDa protein, potentially membrane-bound, which does not seem to be significantly targeted by glycosylation. This is the first pantetheinase characterization in mosquitoes, and its remarkable downregulation might reflect features impacted by co-selection with the Bin-resistant phenotype or potential roles in the Bin-toxin mode of action that deserve to be investigated.
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Affiliation(s)
- Tatiana M. T. Rezende
- Department of Entomology, Instituto Aggeu Magalhães-Fiocruz, Recife 50740-465, PE, Brazil; (T.M.T.R.); (H.S.G.M.); (Y.M.G.S.); (T.P.R.)
| | - Heverly S. G. Menezes
- Department of Entomology, Instituto Aggeu Magalhães-Fiocruz, Recife 50740-465, PE, Brazil; (T.M.T.R.); (H.S.G.M.); (Y.M.G.S.); (T.P.R.)
| | - Antonio M. Rezende
- Department of Microbiology, Instituto Aggeu Magalhães-Fiocruz, Recife 50740-465, PE, Brazil; (A.M.R.); (M.P.C.); (O.P.d.-M.-N.)
| | - Milena P. Cavalcanti
- Department of Microbiology, Instituto Aggeu Magalhães-Fiocruz, Recife 50740-465, PE, Brazil; (A.M.R.); (M.P.C.); (O.P.d.-M.-N.)
| | - Yuri M. G. Silva
- Department of Entomology, Instituto Aggeu Magalhães-Fiocruz, Recife 50740-465, PE, Brazil; (T.M.T.R.); (H.S.G.M.); (Y.M.G.S.); (T.P.R.)
| | - Osvaldo P. de-Melo-Neto
- Department of Microbiology, Instituto Aggeu Magalhães-Fiocruz, Recife 50740-465, PE, Brazil; (A.M.R.); (M.P.C.); (O.P.d.-M.-N.)
| | - Tatiany P. Romão
- Department of Entomology, Instituto Aggeu Magalhães-Fiocruz, Recife 50740-465, PE, Brazil; (T.M.T.R.); (H.S.G.M.); (Y.M.G.S.); (T.P.R.)
| | - Maria Helena N. L. Silva-Filha
- Department of Entomology, Instituto Aggeu Magalhães-Fiocruz, Recife 50740-465, PE, Brazil; (T.M.T.R.); (H.S.G.M.); (Y.M.G.S.); (T.P.R.)
- National Institute for Molecular Entomology, Rio de Janeiro 21941-902, RJ, Brazil
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24
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Rudd SR, Miranda LS, Curtis HR, Bigot Y, Diaz-Mendoza M, Hice R, Nizet V, Park HW, Blaha G, Federici BA, Bideshi DK. The Parasporal Body of Bacillus thuringiensis subsp. israelensis: A Unique Phage Capsid-Associated Prokaryotic Insecticidal Organelle. BIOLOGY 2023; 12:1421. [PMID: 37998020 PMCID: PMC10669011 DOI: 10.3390/biology12111421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 11/09/2023] [Accepted: 11/09/2023] [Indexed: 11/25/2023]
Abstract
The three most important commercial bacterial insecticides are all derived from subspecies of Bacillus thuringiensis (Bt). Specifically, Bt subsp. kurstaki (Btk) and Bt subsp. aizawai (Bta) are used to control larval lepidopteran pests. The third, Bt subsp. israelensis (Bti), is primarily used to control mosquito and blackfly larvae. All three subspecies produce a parasporal body (PB) during sporulation. The PB is composed of insecticidal proteins that damage the midgut epithelium, initiating a complex process that results in the death of the insect. Among these three subspecies of Bt, Bti is unique as it produces the most complex PB consisting of three compartments. Each compartment is bound by a multilaminar fibrous matrix (MFM). Two compartments contain one protein each, Cry11Aa1 and Cyt1Aa1, while the third contains two, Cry4Aa1/Cry4Ba1. Each compartment is packaged independently before coalescing into the mature spherical PB held together by additional layers of the MFM. This distinctive packaging process is unparalleled among known bacterial organelles, although the underlying molecular biology is yet to be determined. Here, we present structural and molecular evidence that the MFM has a hexagonal pattern to which Bti proteins Bt152 and Bt075 bind. Bt152 binds to a defined spot on the MFM during the development of each compartment, yet its function remains unknown. Bt075 appears to be derived from a bacteriophage major capsid protein (MCP), and though its sequence has markedly diverged, it shares striking 3-D structural similarity to the Escherichia coli phage HK97 Head 1 capsid protein. Both proteins are encoded on Bti's pBtoxis plasmid. Additionally, we have also identified a six-amino acid motif that appears to be part of a novel molecular process responsible for targeting the Cry and Cyt proteins to their cytoplasmic compartments. This paper describes several previously unknown features of the Bti organelle, representing a first step to understanding the biology of a unique process of sorting and packaging of proteins into PBs. The insights from this research suggest a potential for future applications in nanotechnology.
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Affiliation(s)
- Sarah R. Rudd
- Program in Biomedical Sciences, Department of Biological Sciences, California Baptist University, Riverside, CA 92504, USA; (S.R.R.); (L.S.M.); (H.R.C.); (H.-W.P.)
- School of Medicine, Loma Linda University, Loma Linda, CA 92350, USA
- Department of Pediatrics, School of Medicine, University of California at San Diego, La Jolla, CA 92093, USA;
| | - Leticia Silva Miranda
- Program in Biomedical Sciences, Department of Biological Sciences, California Baptist University, Riverside, CA 92504, USA; (S.R.R.); (L.S.M.); (H.R.C.); (H.-W.P.)
| | - Hannah R. Curtis
- Program in Biomedical Sciences, Department of Biological Sciences, California Baptist University, Riverside, CA 92504, USA; (S.R.R.); (L.S.M.); (H.R.C.); (H.-W.P.)
- School of Medicine, Loma Linda University, Loma Linda, CA 92350, USA
| | - Yves Bigot
- UMR CNRS7247, Centre INRA Val de Loire, 37380 Nouzilly, France;
| | - Mercedes Diaz-Mendoza
- Department of Biochemistry and Molecular Biology, Faculty of Chemical and Biological Sciences, University Complutense of Madrid, 28040 Madrid, Spain;
| | - Robert Hice
- Department of Entomology, University of California, Riverside, CA 92521, USA;
| | - Victor Nizet
- Department of Pediatrics, School of Medicine, University of California at San Diego, La Jolla, CA 92093, USA;
| | - Hyun-Woo Park
- Program in Biomedical Sciences, Department of Biological Sciences, California Baptist University, Riverside, CA 92504, USA; (S.R.R.); (L.S.M.); (H.R.C.); (H.-W.P.)
| | - Gregor Blaha
- Department of Biochemistry, University of California, Riverside, CA 92521, USA;
| | - Brian A. Federici
- Department of Entomology, University of California, Riverside, CA 92521, USA;
| | - Dennis K. Bideshi
- Program in Biomedical Sciences, Department of Biological Sciences, California Baptist University, Riverside, CA 92504, USA; (S.R.R.); (L.S.M.); (H.R.C.); (H.-W.P.)
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25
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Šolinc G, Anderluh G, Podobnik M. Bacillus thuringiensis toxin Cyt2Aa forms filamentous oligomers when exposed to lipid membranes or detergents. Biochem Biophys Res Commun 2023; 674:44-52. [PMID: 37393643 DOI: 10.1016/j.bbrc.2023.06.078] [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: 05/26/2023] [Revised: 06/06/2023] [Accepted: 06/25/2023] [Indexed: 07/04/2023]
Abstract
The bacterium Bacillus thuringiensis (Bt) produces insecticidal proteins during the sporulation phase. These proteins are located in parasporal crystals consisting of two delta-endotoxin classes, crystal (Cry) and cytolytic (Cyt) toxins. In vitro, Cyt toxins show cytolytic activity against bacterial and a variety of insect and mammalian cells. They bind to cell membranes with unsaturated phospholipids and sphingomyelin. Although Bt and its parasporal crystals containing both Cry and Cyt toxins have been successfully used as bioinsecticides, the molecular mechanism of action of Cyt toxins is not yet fully understood. To address this, we exposed Cyt2Aa to lipid membranes and visualized membrane disruption process using cryo-electron microscopy. We observed two types of Cyt2Aa oligomers. First, Cyt2Aa forms smaller curved oligomers on the membrane surface that become linear over time, and detach when the membrane ruptures. Similar linear filamentous oligomers were also formed by Cyt2Aa in the presence of detergents without prior exposure to lipid membranes, which exhibited attenuated cytolytic activity. Furthermore, our data suggest that Cyt2Aa adopts different conformations between its monomeric and oligomeric forms. Overall, our results provide new evidence for a detergent-like mechanism of action of Cyt2Aa rather than the pore-forming model of target membrane disruption of this important class of insecticidal proteins.
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Affiliation(s)
- Gašper Šolinc
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova ulica 19, 1000, Ljubljana, Slovenia; Biotechnical Faculty, University of Ljubljana, Jamnikarjeva ulica 101, 1000, Ljubljana, Slovenia.
| | - Gregor Anderluh
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova ulica 19, 1000, Ljubljana, Slovenia.
| | - Marjetka Podobnik
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova ulica 19, 1000, Ljubljana, Slovenia.
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26
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Nkahe DL, Sonhafouo-Chiana N, Ndjeunia Mbiakop P, Kekeunou S, Mimpfoundi R, Awono-Ambene P, Wondji CS, Antonio-Nkondjio C. Can the use of larviciding with biological compounds contribute in increasing Anopheles gambiae s.l. susceptibility to pyrethroid in a population expressing high resistance intensity? PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2023; 195:105569. [PMID: 37666599 DOI: 10.1016/j.pestbp.2023.105569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 08/05/2023] [Indexed: 09/06/2023]
Abstract
BACKGROUND Larviciding using non-insecticide compounds is considered appropriate for controlling outdoor biting mosquitoes and for managing insecticide resistance. However, there is still not enough information on the influence of larviciding in managing pyrethroid resistance. In the present study, we checked whether the introduction of larviciding using the biolarvicide VectoMax G in the city of Yaoundé is contributing in restoring the susceptibility of An. coluzzii populations to pyrethroids. METHODOLOGY The susceptibility status of field An. coluzzii population was evaluated at different time points before and during larviciding treatments. In addition, An. coluzzii larvae collected in the city of Yaoundé, were split into four groups and exposed to different selection regimes for many generations as follow; (i): deltamethrin 0.05%_only, (ii): Vectomax_only, (iii): Vectomax+deltamethrin 0.05%, (iv): VectoMax+deltamethrin 0.05% + susceptible. Life traits parameters were measured in the progeny and compared between colonies. The control was the susceptible laboratory strain "Ngousso". Kdr allele frequency and the profile of expression of different detoxification genes and oxidative stress genes was checked using qPCR analysis. Gene's expression was compared between the first and the last generation of each colony and in field populations collected before and during larviciding. RESULTS An increase in mosquito susceptibility to deltamethrin and permethrin was recorded for the field populations after larviciding implementation. Resistance intensity to deltamethrin was found to decrease from high to low in field populations. Only the colony vectomax+deltamethrin+susceptible presented a high susceptibility to deltamethrin after 21 generations. The kdr gene frequency was found to be unchanged in the field population and laboratory colonies. A significant decrease in the overexpression profile of Gste2 was detected in field population after larviciding implementation. Other genes showing a similar pattern though not significant were Cyp6z1, Cyp6p1 and Cyp6g16. Concerning fitness only the colony vectomax+deltamethrin+susceptible was found to display a fitness profile similar to the susceptible colony with high fecundity, high hatching rate, short development time and long adult survival rate. CONCLUSION The profile of the field population supported reversal of phenotypic resistance to pyrethroids however no reduction in the frequency of the kdr allele was recorded. Some detoxification genes were detected less overexpressed. The study suggest that reversal may take longer to achieve in a population expressing a very high resistance profile and under continuous insecticide selection pressure.
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Affiliation(s)
- Diane Leslie Nkahe
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroon; Department of Animal Physiology and Biology, Faculty of Science, University of Yaoundé I, P.O. Box 337, Yaoundé, Cameroon
| | - Nadege Sonhafouo-Chiana
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroon; Faculty of Science, University of Buea, Buea, P.O. Box 63, Cameroon
| | - Paulette Ndjeunia Mbiakop
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroon; Department of Animal Physiology and Biology, Faculty of Science, University of Yaoundé I, P.O. Box 337, Yaoundé, Cameroon
| | - Sévilor Kekeunou
- Department of Animal Physiology and Biology, Faculty of Science, University of Yaoundé I, P.O. Box 337, Yaoundé, Cameroon
| | - Rémy Mimpfoundi
- Department of Animal Physiology and Biology, Faculty of Science, University of Yaoundé I, P.O. Box 337, Yaoundé, Cameroon
| | - Parfait Awono-Ambene
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroon
| | - Charles Sinclair Wondji
- Centre for Research in Infectious Diseases (CRID), P.O. Box 13591, Yaoundé, Cameroon; Vector Biology Liverpool School of Tropical medicine Pembroke Place, Liverpool L3 5QA, UK.
| | - Christophe Antonio-Nkondjio
- Institut de Recherche de Yaoundé (IRY), Organisation de Coordination pour la lutte Contre les Endémies en Afrique Centrale (OCEAC), P.O. Box 288, Yaoundé, Cameroon; Faculty of Medicine Paris-Sud, 63 rue Gabriel Peri, 94276, Le Kremlin-Bicêtre, Paris, France..
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Martin CL, Chester DW, Radka CD, Pan L, Yang Z, Hart RC, Binshtein EM, Wang Z, Nagy L, DeLucas LJ, Aller SG. Structures of the Insecticidal Toxin Complex Subunit XptA2 Highlight Roles for Flexible Domains. Int J Mol Sci 2023; 24:13221. [PMID: 37686027 PMCID: PMC10487846 DOI: 10.3390/ijms241713221] [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: 07/31/2023] [Revised: 08/18/2023] [Accepted: 08/20/2023] [Indexed: 09/10/2023] Open
Abstract
The Toxin Complex (Tc) superfamily consists of toxin translocases that contribute to the targeting, delivery, and cytotoxicity of certain pathogenic Gram-negative bacteria. Membrane receptor targeting is driven by the A-subunit (TcA), which comprises IgG-like receptor binding domains (RBDs) at the surface. To better understand XptA2, an insect specific TcA secreted by the symbiont X. nematophilus from the intestine of entomopathogenic nematodes, we determined structures by X-ray crystallography and cryo-EM. Contrary to a previous report, XptA2 is pentameric. RBD-B exhibits an indentation from crystal packing that indicates loose association with the shell and a hotspot for possible receptor binding or a trigger for conformational dynamics. A two-fragment XptA2 lacking an intact linker achieved the folded pre-pore state like wild type (wt), revealing no requirement of the linker for protein folding. The linker is disordered in all structures, and we propose it plays a role in dynamics downstream of the initial pre-pore state.
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Affiliation(s)
- Cole L. Martin
- Department of Pharmacology & Toxicology, University of Alabama at Birmingham, Birmingham, AL 35205, USA; (C.L.M.); (D.W.C.); (C.D.R.); (L.P.)
| | - David W. Chester
- Department of Pharmacology & Toxicology, University of Alabama at Birmingham, Birmingham, AL 35205, USA; (C.L.M.); (D.W.C.); (C.D.R.); (L.P.)
| | - Christopher D. Radka
- Department of Pharmacology & Toxicology, University of Alabama at Birmingham, Birmingham, AL 35205, USA; (C.L.M.); (D.W.C.); (C.D.R.); (L.P.)
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky, Lexington, KY 40536, USA
| | - Lurong Pan
- Department of Pharmacology & Toxicology, University of Alabama at Birmingham, Birmingham, AL 35205, USA; (C.L.M.); (D.W.C.); (C.D.R.); (L.P.)
| | - Zhengrong Yang
- Department of Biochemistry & Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35205, USA;
| | - Rachel C. Hart
- Department of Pathology, Microbiology & Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA; (R.C.H.); (E.M.B.)
| | - Elad M. Binshtein
- Department of Pathology, Microbiology & Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA; (R.C.H.); (E.M.B.)
| | - Zhao Wang
- Biochemistry & Molecular Pharmacology, Cryo-Electron Microscopy and Tomography Core, Baylor College of Medicine, Houston, TX 77030, USA;
| | - Lisa Nagy
- Department of Mathematics, Engineering & Physical Sciences, Jefferson State Community College, Jefferson Campus, Birmingham, AL 35215, USA;
| | - Lawrence J. DeLucas
- Predictive Oncology Inc., 200 Riverhills Business Park, Suite 250, Birmingham, AL 35242, USA;
| | - Stephen G. Aller
- Department of Pharmacology & Toxicology, University of Alabama at Birmingham, Birmingham, AL 35205, USA; (C.L.M.); (D.W.C.); (C.D.R.); (L.P.)
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Menezes HSG, Costa-Latgé SG, Genta FA, Napoleão TH, Paiva PMG, Romão TP, Silva-Filha MHNL. A Culex quinquefasciatus strain resistant to the binary toxin from Lysinibacillus sphaericus displays altered enzyme activities and energy reserves. Parasit Vectors 2023; 16:273. [PMID: 37559134 PMCID: PMC10413512 DOI: 10.1186/s13071-023-05893-z] [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: 05/03/2023] [Accepted: 07/20/2023] [Indexed: 08/11/2023] Open
Abstract
BACKGROUND The resistance of a Culex quinquefasciatus strain to the binary (Bin) larvicidal toxin from Lysinibacillus sphaericus is due to the lack of expression of the toxin's receptors, the membrane-bound Cqm1 α-glucosidases. A previous transcriptomic profile of the resistant larvae showed differentially expressed genes coding Cqm1, lipases, proteases and other genes involved in lipid and carbohydrate metabolism. This study aimed to investigate the metabolic features of Bin-resistant individuals by comparing the activity of some enzymes, energy reserves, fertility and fecundity to a susceptible strain. METHODS The activity of specific enzymes was recorded in midgut samples from resistant and susceptible larvae. The amount of lipids and reducing sugars was determined for larvae and adults from both strains. Additionally, the fecundity and fertility parameters of these strains under control and stress conditions were examined. RESULTS Enzyme assays showed that the esterase activities in the midgut of resistant larvae were significantly lower than susceptible ones using acetyl-, butyryl- and heptanoyl-methylumbelliferyl esthers as substrates. The α-glucosidase activity was also reduced in resistant larvae using sucrose and a synthetic substrate. No difference in protease activities as trypsins, chymotrypsins and aminopeptidases was detected between resistant and susceptible larvae. In larval and adult stages, the resistant strain showed an altered profile of energy reserves characterized by significantly reduced levels of lipids and a greater amount of reducing sugars. The fertility and fecundity of females were similar for both strains, indicating that those changes in energy reserves did not affect these reproductive parameters. CONCLUSIONS Our dataset showed that Bin-resistant insects display differential metabolic features co-selected with the phenotype of resistance that can potentially have effects on mosquito fitness, in particular, due to the reduced lipid accumulation.
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Affiliation(s)
- Heverly Suzany G Menezes
- Department of Entomology, Instituto Aggeu Magalhães-FIOCRUZ, Av. Moraes Rego s/n, Recife, PE, 50740-465, Brazil
| | - Samara G Costa-Latgé
- Laboratory of Insect Biochemistry and Physiology, Instituto Oswaldo Cruz-FIOCRUZ, Rio de Janeiro, RJ, 21045-900, Brazil
| | - Fernando A Genta
- Laboratory of Insect Biochemistry and Physiology, Instituto Oswaldo Cruz-FIOCRUZ, Rio de Janeiro, RJ, 21045-900, Brazil
- National Institute for Molecular Entomology, Rio de Janeiro, RJ, 21941-902, Brazil
| | - Thiago H Napoleão
- Department of Biochemistry, Universidade Federal de Pernambuco, Recife, PE, 50670-901, Brazil
| | - Patrícia M G Paiva
- Department of Biochemistry, Universidade Federal de Pernambuco, Recife, PE, 50670-901, Brazil
| | - Tatiany P Romão
- Department of Entomology, Instituto Aggeu Magalhães-FIOCRUZ, Av. Moraes Rego s/n, Recife, PE, 50740-465, Brazil
| | - Maria Helena N L Silva-Filha
- Department of Entomology, Instituto Aggeu Magalhães-FIOCRUZ, Av. Moraes Rego s/n, Recife, PE, 50740-465, Brazil.
- National Institute for Molecular Entomology, Rio de Janeiro, RJ, 21941-902, Brazil.
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Mouawad C, Awad MK, Liegeois S, Ferrandon D, Sanchis-Borja V, El Chamy L. The NF-κB factor Relish is essential for the epithelial defenses protecting against δ-endotoxin dependent effects of Bacillus thuringiensis israelensis infection in the Drosophila model. Res Microbiol 2023; 174:104089. [PMID: 37348743 DOI: 10.1016/j.resmic.2023.104089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 05/29/2023] [Accepted: 06/09/2023] [Indexed: 06/24/2023]
Abstract
Bacillus thuringiensis israelensis is largely regarded as the most selective, safe and ecofriendly biopesticide used for the control of insect vectors of human diseases. Bti enthomopathogenicity relies on the Cry and Cyt δ-endotoxins, produced as crystalline inclusions during sporulation. Insecticidal selectivity of Bti is mainly ascribed to the binding of the Cry toxins to receptors in the gut of target insects. However, the contribution of epithelial defenses in limiting Bti side effects in non-target species remains largely unexplored. Here, taking advantage of the genetically tractable Drosophila melanogaster model and its amenability for deciphering highly conserved innate immune defenses, we unravel a central role of the NF-κB factor Relish in the protection against the effects of ingested Bti spores in a non-susceptible host. Intriguingly, our data indicate that the Bti-induced Relish response is independent of its canonical activation downstream of peptidoglycan sensing and does not involve its longstanding role in the regulation of antimicrobial peptides encoding genes. In contrast, our data highlight a novel enterocyte specific function of Relish that is essential for preventing general septicemia following Bti oral infections strictly when producing δ-endotoxins. Altogether, our data provide novel insights into Bti-hosts interactions of prominent interest for the optimization and sustainability of insects' biocontrol strategies.
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Affiliation(s)
- Carine Mouawad
- Unité de Recherche Environnement, Génomique et Protéomique, Faculté des Sciences, Université Saint-Joseph de Beyrouth-Liban, Mar Roukos, Mkalles, Beirut, Lebanon.
| | - Mireille Kallassy Awad
- Unité de Recherche Environnement, Génomique et Protéomique, Faculté des Sciences, Université Saint-Joseph de Beyrouth-Liban, Mar Roukos, Mkalles, Beirut, Lebanon.
| | - Samuel Liegeois
- Université de Strasbourg, Strasbourg, France; Modèles Insectes de l'Immunité Innée, UPR 9022 du CNRS, Strasbourg, France.
| | - Dominique Ferrandon
- Université de Strasbourg, Strasbourg, France; Modèles Insectes de l'Immunité Innée, UPR 9022 du CNRS, Strasbourg, France.
| | - Vincent Sanchis-Borja
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, Jouy-en-Josas, France.
| | - Laure El Chamy
- Unité de Recherche Environnement, Génomique et Protéomique, Faculté des Sciences, Université Saint-Joseph de Beyrouth-Liban, Mar Roukos, Mkalles, Beirut, Lebanon.
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Sivabalakrishnan K, Thanihaichelvan M, Tharsan A, Eswaramohan T, Ravirajan P, Hemphill A, Ramasamy R, Surendran SN. Resistance to the larvicide temephos and altered egg and larval surfaces characterize salinity-tolerant Aedes aegypti. Sci Rep 2023; 13:8160. [PMID: 37208485 DOI: 10.1038/s41598-023-35128-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 05/12/2023] [Indexed: 05/21/2023] Open
Abstract
Aedes aegypti, the principal global vector of arboviral diseases and previously considered to oviposit and undergo preimaginal development only in fresh water, has recently been shown to be capable of developing in coastal brackish water containing up to 15 g/L salt. We investigated surface changes in eggs and larval cuticles by atomic force and scanning electron microscopy, and larval susceptibility to two widely-used larvicides, temephos and Bacillus thuringiensis, in brackish water-adapted Ae. aegypti. Compared to freshwater forms, salinity-tolerant Ae. aegypti had rougher and less elastic egg surfaces, eggs that hatched better in brackish water, rougher larval cuticle surfaces, and larvae more resistant to the organophosphate insecticide temephos. Larval cuticle and egg surface changes in salinity-tolerant Ae. aegypti are proposed to respectively contribute to the increased temephos resistance and egg hatchability in brackish water. The findings highlight the importance of extending Aedes vector larval source reduction efforts to brackish water habitats and monitoring the efficacy of larvicides in coastal areas worldwide.
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Affiliation(s)
| | | | - Annathurai Tharsan
- Department of Zoology, Faculty of Science, University of Jaffna, Jaffna, 40000, Sri Lanka
| | - Thamboe Eswaramohan
- Department of Zoology, Faculty of Science, University of Jaffna, Jaffna, 40000, Sri Lanka
| | | | - Andrew Hemphill
- Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, Institute of Parasitology, University of Bern, Länggass-Strasse 122, 3012, Bern, Switzerland
| | - Ranjan Ramasamy
- Department of Zoology, Faculty of Science, University of Jaffna, Jaffna, 40000, Sri Lanka.
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Pacheco S, Gómez I, Peláez-Aguilar AE, Verduzco-Rosas LA, García-Suárez R, do Nascimento NA, Rivera-Nájera LY, Cantón PE, Soberón M, Bravo A. Structural changes upon membrane insertion of the insecticidal pore-forming toxins produced by Bacillus thuringiensis. FRONTIERS IN INSECT SCIENCE 2023; 3:1188891. [PMID: 38469496 PMCID: PMC10926538 DOI: 10.3389/finsc.2023.1188891] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Accepted: 04/04/2023] [Indexed: 03/13/2024]
Abstract
Different Bacillus thuringiensis (Bt) strains produce a broad variety of pore-forming toxins (PFTs) that show toxicity against insects and other invertebrates. Some of these insecticidal PFT proteins have been used successfully worldwide to control diverse insect crop pests. There are several studies focused on describing the mechanism of action of these toxins that have helped to improve their performance and to cope with the resistance evolved by different insects against some of these proteins. However, crucial information that is still missing is the structure of pores formed by some of these PFTs, such as the three-domain crystal (Cry) proteins, which are the most commercially used Bt toxins in the biological control of insect pests. In recent years, progress has been made on the identification of the structural changes that certain Bt insecticidal PFT proteins undergo upon membrane insertion. In this review, we describe the models that have been proposed for the membrane insertion of Cry toxins. We also review the recently published structures of the vegetative insecticidal proteins (Vips; e.g. Vip3) and the insecticidal toxin complex (Tc) in the membrane-inserted state. Although different Bt PFTs show different primary sequences, there are some similarities in the three-dimensional structures of Vips and Cry proteins. In addition, all PFTs described here must undergo major structural rearrangements to pass from a soluble form to a membrane-inserted state. It is proposed that, despite their structural differences, all PFTs undergo major structural rearrangements producing an extended α-helix, which plays a fundamental role in perforating their target membrane, resulting in the formation of the membrane pore required for their insecticidal activity.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Alejandra Bravo
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, Mexico
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Ma X, Hu J, Ding C, Portieles R, Xu H, Gao J, Du L, Gao X, Yue Q, Zhao L, Borrás-Hidalgo O. New native Bacillus thuringiensis strains induce high insecticidal action against Culex pipiens pallens larvae and adults. BMC Microbiol 2023; 23:100. [PMID: 37055727 PMCID: PMC10099900 DOI: 10.1186/s12866-023-02842-9] [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: 01/24/2023] [Accepted: 03/28/2023] [Indexed: 04/15/2023] Open
Abstract
Mosquitoes of many species are key disease vectors, killing millions of people each year. Bacillus thuringiensis-based insecticide formulations are largely recognized as among the most effective, ecologically safe, and long-lasting methods of managing insect pests. New B. thuringiensis strains with high mosquito control effectiveness were isolated, identified, genetically defined, and physiologically characterized. Eight B. thuringiensis strains were identified and shown to carry endotoxin-producing genes. Using a scanning electron microscope, results revealed typical crystal forms of various shapes in B. thuringiensis strains. Fourteen cry and cyt genes were found in the strains examined. Although the genome of the B. thuringiensis A4 strain had twelve cry and cyt genes, not all of them were expressed, and only a few protein profiles were observed. The larvicidal activity of the eight B. thuringiensis strains was found to be positive (LC50: 1.4-28.5 g/ml and LC95: 15.3-130.3 g/ml). Bioassays in a laboratory environment demonstrated that preparations containing B. thuringiensis spores and crystals were particularly active to mosquito larvae and adults. These new findings show that the novel preparation containing B. thuringiensis A4 spores and crystals mixture might be used to control larval and adult mosquitoes in a sustainable and ecologically friendly manner.
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Affiliation(s)
- Xinmin Ma
- Joint R and D Center of Biotechnology, RETDA, Yotabio-Engineering Co., Ltd, 99 Shenzhen Road, Rizhao, 276826, Shandong, People's Republic of China
| | - Jianjian Hu
- Joint R and D Center of Biotechnology, RETDA, Yotabio-Engineering Co., Ltd, 99 Shenzhen Road, Rizhao, 276826, Shandong, People's Republic of China
| | - Chengsong Ding
- Joint R and D Center of Biotechnology, RETDA, Yotabio-Engineering Co., Ltd, 99 Shenzhen Road, Rizhao, 276826, Shandong, People's Republic of China
| | - Roxana Portieles
- Joint R and D Center of Biotechnology, RETDA, Yotabio-Engineering Co., Ltd, 99 Shenzhen Road, Rizhao, 276826, Shandong, People's Republic of China
| | - Hongli Xu
- Joint R and D Center of Biotechnology, RETDA, Yotabio-Engineering Co., Ltd, 99 Shenzhen Road, Rizhao, 276826, Shandong, People's Republic of China
| | - Jingyao Gao
- Joint R and D Center of Biotechnology, RETDA, Yotabio-Engineering Co., Ltd, 99 Shenzhen Road, Rizhao, 276826, Shandong, People's Republic of China
| | - Lihua Du
- Joint R and D Center of Biotechnology, RETDA, Yotabio-Engineering Co., Ltd, 99 Shenzhen Road, Rizhao, 276826, Shandong, People's Republic of China
| | - Xiangyou Gao
- Joint R and D Center of Biotechnology, RETDA, Yotabio-Engineering Co., Ltd, 99 Shenzhen Road, Rizhao, 276826, Shandong, People's Republic of China
| | - Qiulin Yue
- State Key Laboratory of Biobased Material and Green Papermaking, Shandong Provincial Key Lab of Microbial Engineering, Qilu University of Technology (Shandong Academic of Science), Jinan, People's Republic of China
| | - Lin Zhao
- State Key Laboratory of Biobased Material and Green Papermaking, Shandong Provincial Key Lab of Microbial Engineering, Qilu University of Technology (Shandong Academic of Science), Jinan, People's Republic of China
| | - Orlando Borrás-Hidalgo
- Joint R and D Center of Biotechnology, RETDA, Yotabio-Engineering Co., Ltd, 99 Shenzhen Road, Rizhao, 276826, Shandong, People's Republic of China.
- State Key Laboratory of Biobased Material and Green Papermaking, Shandong Provincial Key Lab of Microbial Engineering, Qilu University of Technology (Shandong Academic of Science), Jinan, People's Republic of China.
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Bacillus thuringiensis Cyt Proteins as Enablers of Activity of Cry and Tpp Toxins against Aedes albopictus. Toxins (Basel) 2023; 15:toxins15030211. [PMID: 36977103 PMCID: PMC10054650 DOI: 10.3390/toxins15030211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 02/27/2023] [Accepted: 03/08/2023] [Indexed: 03/14/2023] Open
Abstract
Aedes albopictus is a species of mosquito, originally from Southeast Asia, that belongs to the Culicidae family and the Dipteran insect order. The distribution of this vector has rapidly changed over the past decade, making most of the temperate territories in the world vulnerable to important human vector-borne diseases such as dengue, yellow fever, zika or chikungunya. Bacillus thuringiensis var. israeliensis (Bti)-based insecticides represent a realistic alternative to the most common synthetic insecticides for the control of mosquito larvae. However, several studies have revealed emerging resistances to the major Bti Crystal proteins such as Cry4Aa, Cry4Ba and Cry11Aa, making the finding of new toxins necessary to diminish the exposure to the same toxicity factors overtime. Here, we characterized the individual activity of Cyt1Aa, Cry4Aa, Cry4Ba and Cry11Aa against A. albopictus and found a new protein, Cyt1A-like, that increases the activity of Cry11Aa more than 20-fold. Additionally, we demonstrated that Cyt1A-like facilitates the activity three new Bti toxins: Cry53-like, Cry56A-like and Tpp36-like. All in all, these results provide alternatives to the currently available Bti products for the control of mosquito populations and position Cyt proteins as enablers of activity for otherwise non-active crystal proteins.
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MosChito rafts as effective and eco-friendly tool for the delivery of a Bacillus thuringiensis-based insecticide to Aedes albopictus larvae. Sci Rep 2023; 13:3041. [PMID: 36810640 PMCID: PMC9944263 DOI: 10.1038/s41598-023-29501-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 02/06/2023] [Indexed: 02/23/2023] Open
Abstract
Adult mosquito females, through their bites, are responsible for the transmission of different zoonotic pathogens. Although adult control represents a pillar for the prevention of disease spread, larval control is also crucial. Herein we characterized the effectiveness of a suitable tool, named "MosChito raft", for the aquatic delivery of a Bacillus thuringiensis var. israelensis (Bti) formulate, a bioinsecticide active by ingestion against mosquito larvae. MosChito raft is a floating tool composed by chitosan cross-linked with genipin in which a Bti-based formulate and an attractant have been included. MosChito rafts (i) resulted attractive for the larvae of the Asian tiger mosquito Aedes albopictus, (ii) induced larval mortality within a few hours of exposure and, more importantly, (iii) protected the Bti-based formulate, whose insecticidal activity was maintained for more than one month in comparison to the few days residual activity of the commercial product. The delivery method was effective in both laboratory and semi-field conditions, demonstrating that MosChito rafts may represent an original, eco-based and user-friendly solution for larval control in domestic and peri-domestic aquatic habitats such as saucers and artificial containers in residential or urban environments.
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Jiang K, Chen Z, Zang Y, Shi Y, Shang C, Jiao X, Cai J, Gao X. Functional characterization of Vip3Aa from Bacillus thuringiensis reveals the contributions of specific domains to its insecticidal activity. J Biol Chem 2023; 299:103000. [PMID: 36764522 PMCID: PMC10017365 DOI: 10.1016/j.jbc.2023.103000] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 01/31/2023] [Accepted: 02/02/2023] [Indexed: 02/11/2023] Open
Abstract
Microbially derived, protein-based biopesticides offer a more sustainable pest management alternative to synthetic pesticides. Vegetative insecticidal proteins (Vip3), multidomain proteins secreted by Bacillus thuringiensis, represent a second-generation insecticidal toxin that has been preliminarily used in transgenic crops. However, the molecular mechanism underlying Vip3's toxicity is poorly understood. Here, we determine the distinct functions and contributions of the domains of the Vip3Aa protein to its toxicity against Spodoptera frugiperda larvae. We demonstrate that Vip3Aa domains II and III (DII-DIII) bind the midgut epithelium, while DI is essential for Vip3Aa's stability and toxicity inside the protease-enriched host insect midgut. DI-DIII can be activated by midgut proteases and exhibits cytotoxicity similar to full-length Vip3Aa. In addition, we determine that DV can bind the peritrophic matrix via its glycan-binding activity, which contributes to Vip3Aa insecticidal activity. In summary, this study provides multiple insights into Vip3Aa's mode-of-action which should significantly facilitate the clarification of its insecticidal mechanism and its further rational development.
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Affiliation(s)
- Kun Jiang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Zhe Chen
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Yuanrong Zang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Yiting Shi
- School of Life Sciences, Shandong University, Qingdao, China; Taishan College, Shandong University, Jinan, China
| | - Chengbin Shang
- School of Life Sciences, Shandong University, Qingdao, China
| | - Xuyao Jiao
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Jun Cai
- Department of Microbiology, College of Life Sciences, Nankai University, Tianjin, China
| | - Xiang Gao
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China.
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Aromatic Residues on the Side Surface of Cry4Ba-Domain II of Bacillus thuringiensis subsp. israelensis Function in Binding to Their Counterpart Residues on the Aedes aegypti Alkaline Phosphatase Receptor. Toxins (Basel) 2023; 15:toxins15020114. [PMID: 36828427 PMCID: PMC9960242 DOI: 10.3390/toxins15020114] [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: 12/28/2022] [Revised: 01/22/2023] [Accepted: 01/26/2023] [Indexed: 01/31/2023] Open
Abstract
Receptor binding is a prerequisite process to exert the mosquitocidal activity of the Cry4Ba toxin of Bacillus thuringiensis subsp. israelensis. The beta-sheet prism (domain II) and beta-sheet sandwich (domain III) of the Cry4Ba toxin have been implicated in receptor binding, albeit the precise binding mechanisms of these remain unclear. In this work, alanine scanning was used to determine the contribution to receptor binding of some aromatic and hydrophobic residues on the surface of domains II and III that are predicted to be responsible for binding to the Aedes aegypti membrane-bound alkaline phosphatase (Aa-mALP) receptor. Larvicidal activity assays against A. aegypti larvae revealed that aromatic residues (Trp327 on the β2 strand, Tyr347 on the β3-β4 loop, and Tyr359 on the β4 strand) of domain II were important to the toxicity of the Cry4Ba toxin. Quantitative binding assays using enzyme-linked immunosorbent assay (ELISA) showed similar decreasing trends in binding to the Aa-mALP receptor and in toxicity of the Cry4Ba mutants Trp327Ala, Tyr347Ala, and Tyr359Ala, suggesting that a possible function of these surface-exposed aromatic residues is receptor binding. In addition, binding assays of the Cry4Ba toxin to the mutants of the binding residues Gly513, Ser490, and Phe497 of the Aa-mALP receptor supported the binding function of Trp327, Tyr347, and Tyr359 of the Cry4Ba toxin, respectively. Altogether, our results showed for the first time that aromatic residues on a side surface of the Cry4Ba domain II function in receptor binding. This finding provides greater insight into the possible molecular mechanisms of the Cry4Ba toxin.
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Pacheco S, Gómez I, Soberón M, Bravo A. A major conformational change of N-terminal helices of Bacillus thuringiensis Cry1Ab insecticidal protein is necessary for membrane insertion and toxicity. FEBS J 2022; 290:2692-2705. [PMID: 36560841 DOI: 10.1111/febs.16710] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 12/01/2022] [Accepted: 12/21/2022] [Indexed: 12/24/2022]
Abstract
Pore forming toxins rely on oligomerization for membrane insertion to kill their targets. Bacillus thuringiensis produces insecticidal Cry-proteins composed of three domains that form pores that kill the insect larvae. Domain I is involved in oligomerization and membrane insertion, whereas Domains II and III participate in receptor binding and specificity. However, the structural changes involved in membrane insertion of these proteins remain unsolved. The most widely accepted model for membrane insertion, the 'umbrella model', proposed that the α-4/α-5 hairpin of Domain I swings away and is inserted into the membrane. To determine the topology of Cry1Ab in the membrane, disulfide bonds linking α-helices of Domain I were introduced to restrict their movement. Disulfide bonds between helices α-2/α-3 or α-3/α-4 lost oligomerization and toxicity, indicating that movement of these helices is needed for insecticidal activity. By contrast, disulfide bonds linking helices α-5/α-6 did not affect toxicity, which contradicts the 'umbrella model'. Additionally, Föster resonance energy transfer closest approach analyses measuring distances of different points in the toxin to the membrane plane and collisional quenching assays analysing the protection of specific fluorescent-labeled residues to the soluble potassium iodide quencher in the membrane inserted state were performed. Overall, the data show that Domain I from Cry1Ab may undergo a major conformational change during its membrane insertion, where the N-terminal region (helices α-1 to α-4) participates in oligomerization and toxicity, probably forming an extended helix. These data break a paradigm, showing a new 'folding white-cane model', which better explains the structural changes of Cry toxins during insertion into the membrane.
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Affiliation(s)
- Sabino Pacheco
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Mexico
| | - Isabel Gómez
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Mexico
| | - Mario Soberón
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Mexico
| | - Alejandra Bravo
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Mexico
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38
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Best HL, Williamson LJ, Lipka-Lloyd M, Waller-Evans H, Lloyd-Evans E, Rizkallah PJ, Berry C. The Crystal Structure of Bacillus thuringiensis Tpp80Aa1 and Its Interaction with Galactose-Containing Glycolipids. Toxins (Basel) 2022; 14:863. [PMID: 36548760 PMCID: PMC9784298 DOI: 10.3390/toxins14120863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 11/21/2022] [Accepted: 11/24/2022] [Indexed: 12/13/2022] Open
Abstract
Tpp80Aa1 from Bacillus thuringiensis is a Toxin_10 family protein (Tpp) with reported action against Culex mosquitoes. Here, we demonstrate an expanded target range, showing Tpp80Aa1 is also active against the larvae of Anopheles gambiae and Aedes aegypti mosquitoes. We report the first crystal structure of Tpp80Aa1 at a resolution of 1.8 Å, which shows Tpp80Aa1 consists of two domains: an N-terminal β-trefoil domain resembling a ricin B lectin and a C-terminal putative pore-forming domain sharing structural similarity with the aerolysin family. Similar to other Tpp family members, we observe Tpp80Aa1 binds to the mosquito midgut, specifically the posterior midgut and the gastric caecum. We also identify that Tpp80Aa1 can interact with galactose-containing glycolipids and galactose, and this interaction is critical for exerting full insecticidal action against mosquito target cell lines.
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Affiliation(s)
- Hannah L. Best
- School of Biosciences, Cardiff University, Park Place, Cardiff CF10 3AX, UK
| | | | | | - Helen Waller-Evans
- School of Pharmacy, Cardiff University, Park Place, Cardiff CF10 3AX, UK
| | - Emyr Lloyd-Evans
- School of Biosciences, Cardiff University, Park Place, Cardiff CF10 3AX, UK
| | | | - Colin Berry
- School of Biosciences, Cardiff University, Park Place, Cardiff CF10 3AX, UK
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Mishra R, Hua G, Bagal UR, Champagne DE, Adang MJ. Anopheles gambiae strain (Ag55) cultured cells originated from Anopheles coluzzii and are phagocytic with hemocyte-like gene expression. INSECT SCIENCE 2022; 29:1346-1360. [PMID: 35358364 DOI: 10.1111/1744-7917.13036] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 02/21/2022] [Accepted: 03/07/2022] [Indexed: 06/14/2023]
Abstract
Anopheles gambiae and Anopheles coluzzii are closely related species that are predominant vectors of malaria in Africa. Recently, A. gambiae form M was renamed A. coluzzii and we now conclude on the basis of a diagnostic PCR-restriction fragment length polymorphism assay that Ag55 cells were derived from A. coluzzii. We established an Ag55 cell transcriptome, and KEGG pathway analysis showed that Ag55 cells are enriched in phagosome pathway transcripts. The Ag55 transcriptome has an abundance of specific transcripts characteristic of mosquito hemocytes. Functional E. coli bioparticle uptake experiments visualized by fluorescence microscopy and confocal microscopy and quantified by flow cytometry establish the phagocytic competence of Ag55 cells. Results from this investigation of Ag55 cell properties will guide researchers in the use and engineering of the Ag55 cell line to better enable investigations of Plasmodium, other microbes, and insecticidal toxins.
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Affiliation(s)
- Ruchir Mishra
- Department of Entomology, College of Agricultural and Environmental Sciences, University of Georgia, Athens, Georgia, USA
- Department of Entomology and Nematology, University of Florida, Gainesville, Florida, USA
| | - Gang Hua
- Department of Entomology, College of Agricultural and Environmental Sciences, University of Georgia, Athens, Georgia, USA
| | - Ujwal R Bagal
- Institute of Bioinformatics, University of Georgia, Athens, Georgia, USA
| | - Donald E Champagne
- Department of Entomology, College of Agricultural and Environmental Sciences, University of Georgia, Athens, Georgia, USA
| | - Michael J Adang
- Department of Entomology, College of Agricultural and Environmental Sciences, University of Georgia, Athens, Georgia, USA
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA
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40
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Bio-fabricated zinc oxide and cry protein nanocomposites: Synthesis, characterization, potentiality against Zika, malaria and West Nile virus vector's larvae and their impact on non-target organisms. Int J Biol Macromol 2022; 224:699-712. [DOI: 10.1016/j.ijbiomac.2022.10.158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 09/29/2022] [Accepted: 10/18/2022] [Indexed: 11/05/2022]
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41
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Dechkla M, Charoenjotivadhanakul S, Imtong C, Visitsattapongse S, Li HC, Angsuthanasombat C. Cry4Aa and Cry4Ba Mosquito-Active Toxins Utilize Different Domains in Binding to a Particular Culex ALP Isoform: A Functional Toxin Receptor Implicating Differential Actions on Target Larvae. Toxins (Basel) 2022; 14:toxins14100652. [PMID: 36287921 PMCID: PMC9607545 DOI: 10.3390/toxins14100652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 09/10/2022] [Accepted: 09/16/2022] [Indexed: 11/16/2022] Open
Abstract
The three-domain Cry4Aa toxin produced from Bacillus thuringiensis subsp. israelensis was previously shown to be much more toxic to Culex mosquito larvae than its closely related toxin—Cry4Ba. The interaction of these two individual toxins with target receptors on susceptible larval midgut cells is likely to be the critical determinant in their differential toxicity. Here, two full-length membrane-bound alkaline phosphatase (mALP) isoforms from Culex quinquefasciatus larvae, Cq-mALP1263and Cq-mALP1264, predicted to be GPI-linked was cloned and functionally expressed in Spodoptera frugiperda (Sf9) cells as 57- and 61-kDa membrane-bound proteins, respectively. Bioinformatics analysis disclosed that both Cq-mALP isoforms share significant sequence similarity to Aedes aegypti-mALP—a Cry4Ba toxin receptor. In cytotoxicity assays, Sf9 cells expressing Cq-mALP1264, but not Cq-mALP1263, showed remarkably greater susceptibility to Cry4Aa than Cry4Ba, while immunolocalization studies revealed that both toxins were capable of binding to each Cq-mALP expressed on the cell membrane surface. Molecular docking of the Cq-mALP1264-modeled structure with individual Cry4 toxins revealed that Cry4Aa could bind to Cq-mALP1264 primarily through particular residues on three surface-exposed loops in the receptor-binding domain—DII, including Thr512, Tyr513 and Lys514 in the β10-β11loop. Dissimilarly, Cry4Ba appeared to utilize only certain residues in its C-terminal domain—DIII to interact with such a Culex counterpart receptor. Ala-substitutions of selected β10-β11loop residues (T512A, Y513A and K514A) revealed that only the K514A mutant displayed a drastic decrease in biotoxicity against C. quinquefasciatus larvae. Further substitution of Lys514 with Asp (K514D) revealed a further decrease in larval toxicity. Furthermore, in silico calculation of the binding affinity change (ΔΔGbind) in Cry4Aa-Cq-mALP1264 interactions upon these single-substitutions revealed that the K514D mutation displayed the largest ΔΔGbind value as compared to three other mutations, signifying an adverse impact of a negative charge at this critical receptor-binding position. Altogether, our present study has disclosed that these two related-Cry4 mosquito-active toxins conceivably exploited different domains in functional binding to the same Culex membrane-bound ALP isoform—Cq-mALP1264 for mediating differential toxicity against Culex target larvae.
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Affiliation(s)
- Manussawee Dechkla
- Department of Environmental Biology, Faculty of Science and Technology, Suan Sunandha Rajabhat University, Bangkok 10300, Thailand
- Correspondence: (M.D.); (C.A.)
| | - Sathapat Charoenjotivadhanakul
- Bacterial Toxin Research Innovation Cluster (BRIC), Institute of Molecular Biosciences, Salaya Campus, Mahidol University, Nakorn Pathom 73170, Thailand
| | - Chompounoot Imtong
- Laboratory of Structural Biochemistry and Cell Chemical Biology, Biophysics Institute for Research and Development (BIRD), Fang, Chiang Mai 50110, Thailand
| | - Sarinporn Visitsattapongse
- Department of Biomedical Engineering, School of Engineering, King Mongkut’s Institute of Technology Ladkrabang, Ladkrabang, Bangkok 10520, Thailand
| | - Hui-Chun Li
- Department of Biochemistry, School of Medicine, Tzu Chi University, Hualien 97004, Taiwan
| | - Chanan Angsuthanasombat
- Bacterial Toxin Research Innovation Cluster (BRIC), Institute of Molecular Biosciences, Salaya Campus, Mahidol University, Nakorn Pathom 73170, Thailand
- Laboratory of Structural Biochemistry and Cell Chemical Biology, Biophysics Institute for Research and Development (BIRD), Fang, Chiang Mai 50110, Thailand
- Department of Biochemistry, School of Medicine, Tzu Chi University, Hualien 97004, Taiwan
- Correspondence: (M.D.); (C.A.)
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42
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Complete structure elucidation of a functional form of the Bacillus thuringiensis Cry4Ba δ-endotoxin: Insights into toxin-induced transmembrane pore architecture. Biochem Biophys Res Commun 2022; 620:158-164. [DOI: 10.1016/j.bbrc.2022.06.065] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Accepted: 06/21/2022] [Indexed: 11/24/2022]
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da Silva JS, Oliveira M, Viana JL, da Silva MC, Pinheiro VCS, Zilse GAC, Tadei WP. Cyt1Aa toxin gene frequency in Bacillus thuringiensis isolates and its relation with pathogenicity for vector mosquitoes. Acta Trop 2022; 233:106549. [PMID: 35671782 DOI: 10.1016/j.actatropica.2022.106549] [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: 04/02/2022] [Revised: 06/02/2022] [Accepted: 06/03/2022] [Indexed: 11/28/2022]
Abstract
Bacillus thuringiensis produces several virulence factors, the main ones being the Cry and Cyt toxins, present in the parasporal body produced during sporulation. The Cyt toxins have mechanisms specific for mosquitoes and Cyt1Aa, the most studied cytolytic toxin, is effective for mosquito control by acting in synergism with Cry toxins. The goal of the present work was to study the frequency of the codifying gene for Cyt1Aa in B. thuringiensis native isolates acquired from samples of soil, insect and water, as well as to verify any possible genetic polymorphism. 1,448 B. thuringiensis strains were used for DNA extraction and PCR technique, all with the use of a primer that amplifies a fragment of 300 pairs of the cyt1Aa gene. The strains that showed amplification in the PCR reaction were sequenced and compared to each other and to the sequences available at Genbank. 32 (2.3%) strains of B. thuringiensis showed positive amplification for the cyt1Aa gene. The highest frequency of isolates with cyt1Aa gene was acquired from samples coming from the Cerrado biome, both isolates from soil and from insects, equally with 3.4%. The cyt1Aa gene sequencing highlighted that, for that 300 bp region, the gene is conserved and there is no single-base polymorphism.
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Affiliation(s)
- Joelma S da Silva
- Curso Ciências Naturais, Centro de Ciências de Codó, Universidade Federal do Maranhão, Avenida Dr. José Anselmo, 2008, São Sebastião, Codó, Maranhão, 65400-000, Brasil.
| | - Maxcilene Oliveira
- Laboratório de Entomologia Médica, Departamento de Química e Biologia, Centro de Estudos Superiores de Caxias, Universidade Estadual do Maranhão, Praça Duque de Caxias, s/n, Morro do Alecrim, Caxias, Maranhão, 65604-380, Brasil
| | - Juliete L Viana
- Universidade do Estado do Amazonas - UEA, Programa de Pós-graduação em Biodiversidade e Biotecnologia da Rede BIONORTE - PPG BIONORTE, Av. Carvalho Leal, 1777, Ed. Anexo, 4° andar, Cachoeirinha, CEP 69065001, Manaus, AM, Brasil
| | - Maria C da Silva
- Laboratório de Bactérias Entomopatogênicas e Marcadores Moleculares, Departamento de Química e Biologia, Centro de Estudos Superiores de Caxias, Universidade Estadual do Maranhão, Praça Duque de Caxias, s/n, Morro do Alecrim, Caxias, Maranhão, 65604-380, Brasil
| | - Valéria C S Pinheiro
- Laboratório de Entomologia Médica, Departamento de Química e Biologia, Centro de Estudos Superiores de Caxias, Universidade Estadual do Maranhão, Praça Duque de Caxias, s/n, Morro do Alecrim, Caxias, Maranhão, 65604-380, Brasil
| | - Gislene A C Zilse
- Grupo de Pesquisas em Abelhas, Instituto Nacional de Pesquisas da Amazônia, Programa de Pós-Graduação em Entomologia, Avenida André Araújo, 2936, Petrópolis, Manaus, Amazonas, 69067-375, Brasil
| | - Wanderli P Tadei
- Laboratório de Malária e Dengue, Instituto Nacional de Pesquisas da Amazônia, Programa de Pós-Graduação em Entomologia, Avenida André Araújo, 2936, Petrópolis, Manaus, Amazonas, 69067-375, Brasil
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Vector-Borne Viral Diseases as a Current Threat for Human and Animal Health—One Health Perspective. J Clin Med 2022; 11:jcm11113026. [PMID: 35683413 PMCID: PMC9181581 DOI: 10.3390/jcm11113026] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 05/23/2022] [Accepted: 05/25/2022] [Indexed: 12/15/2022] Open
Abstract
Over the last decades, an increase in the emergence or re-emergence of arthropod-borne viruses has been observed in many regions. Viruses such as dengue, yellow fever, or zika are a threat for millions of people on different continents. On the other hand, some arboviruses are still described as endemic, however, they could become more important in the near future. Additionally, there is a group of arboviruses that, although important for animal breeding, are not a direct threat for human health. Those include, e.g., Schmallenberg, bluetongue, or African swine fever viruses. This review focuses on arboviruses and their major vectors: mosquitoes, ticks, biting midges, and sandflies. We discuss the current knowledge on arbovirus transmission, ecology, and methods of prevention. As arboviruses are a challenge to both human and animal health, successful prevention and control are therefore only possible through a One Health perspective.
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45
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Overcoming Poor Transgene Expression in the Wild-Type Chlamydomonas Chloroplast: Creation of Highly Mosquitocidal Strains of Chlamydomonas reinhardtii. Microorganisms 2022; 10:microorganisms10061087. [PMID: 35744605 PMCID: PMC9229432 DOI: 10.3390/microorganisms10061087] [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: 04/26/2022] [Revised: 05/19/2022] [Accepted: 05/21/2022] [Indexed: 12/10/2022] Open
Abstract
High-level expression of transgenes in the chloroplast of wild-type Chlamydomonas reinhardtii (C. reinhardtii) remains challenging for many genes (e.g., the cry toxin genes from Bacillus thuringiensis israelensis). The bottleneck is presumed to be post-transcriptional and mediated by the 5′ element and the coding region. Using 5′ elements from highly expressed photosynthesis genes such as atpA did not improve the outcome with cry11A regardless of the promoter. However, when we employed the 5′ UTR from mature rps4 mRNA with clean fusions to promoters, production of the rCry11A protein became largely promoter-dependent. The best results were obtained with the native 16S rrn promoter (−91 to −1). When it was fused to the mature 5′ rps4 UTR, rCry11A protein levels were ~50% higher than was obtained with the inducible system, or ~0.6% of total protein. This level was sufficient to visualize the 73-kDa rCry11A protein on Coomassie-stained gels of total algal protein. In addition, analysis of the expression of these transgenes by RT-PCR indicated that RNA levels roughly correlated with protein production. Live cell bioassays using the best strains as food for 3rd instar Aedes aegypti larvae showed that most larvae were killed even when the cell concentration was as low as 2 × 104 cells/mL. Finally, the results indicate that these highly toxic strains are also quite stable, and thus represent a key milestone in using C. reinhardtii for mosquito control.
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46
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Alam I, Batool K, Idris AL, Tan W, Guan X, Zhang L. Role of Lectin in the Response of Aedes aegypti Against Bt Toxin. Front Immunol 2022; 13:898198. [PMID: 35634312 PMCID: PMC9136036 DOI: 10.3389/fimmu.2022.898198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 04/19/2022] [Indexed: 12/05/2022] Open
Abstract
Aedes aegypti is one of the world’s most dangerous mosquitoes, and a vector of diseases such as dengue fever, chikungunya virus, yellow fever, and Zika virus disease. Currently, a major global challenge is the scarcity of antiviral medicine and vaccine for arboviruses. Bacillus thuringiensis var israelensis (Bti) toxins are used as biological mosquito control agents. Endotoxins, including Cry4Aa, Cry4Ba, Cry10Aa, Cry11Aa, and Cyt1Aa, are toxic to mosquitoes. Insect eradication by Cry toxin relies primarily on the interaction of cry toxins with key toxin receptors, such as aminopeptidase (APN), alkaline phosphatase (ALP), cadherin (CAD), and ATP-binding cassette transporters. The carbohydrate recognition domains (CRDs) of lectins and domains II and III of Cry toxins share similar structural folds, suggesting that midgut proteins, such as C-type lectins (CTLs), may interfere with interactions among Cry toxins and receptors by binding to both and alter Cry toxicity. In the present review, we summarize the functional role of C-type lectins in Ae. aegypti mosquitoes and the mechanism underlying the alteration of Cry toxin activity by CTLs. Furthermore, we outline future research directions on elucidating the Bti resistance mechanism. This study provides a basis for understanding Bti resistance, which can be used to develop novel insecticides.
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Affiliation(s)
- Intikhab Alam
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
- Key Lab of Biopesticides and Chemical Biology, MOE, Fujian Agriculture and Forestry University, Fuzhou, China
- College of Life Sciences, South China Agricultural University, Guangzhou, China
| | - Khadija Batool
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
- Key Lab of Biopesticides and Chemical Biology, MOE, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Aisha Lawan Idris
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
- Key Lab of Biopesticides and Chemical Biology, MOE, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Weilong Tan
- Nanjing Bioengineering (Gene) Technology Center for Medicines, Nanjing, China
| | - Xiong Guan
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
- Key Lab of Biopesticides and Chemical Biology, MOE, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Lingling Zhang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
- Key Lab of Biopesticides and Chemical Biology, MOE, Fujian Agriculture and Forestry University, Fuzhou, China
- *Correspondence: Lingling Zhang,
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47
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Batool K, Alam I, Liu P, Shu Z, Zhao S, Yang W, Jie X, Gu J, Chen XG. Recombinant Mosquito Densovirus with Bti Toxins Significantly Improves Pathogenicity against Aedes albopictus. Toxins (Basel) 2022; 14:147. [PMID: 35202174 PMCID: PMC8879223 DOI: 10.3390/toxins14020147] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 02/12/2022] [Accepted: 02/14/2022] [Indexed: 12/12/2022] Open
Abstract
Mosquito densoviruses (MDVs) are mosquito-specific viruses that are recommended as mosquito bio-control agents. The MDV Aedes aegypti densovirus (AeDNV) is a good candidate for controlling mosquitoes. However, the slow activity restricts their widespread use for vector control. In this study, we introduced the Bacillus thuringiensis (Bti) toxin Cry11Aa domain II loop α8 and Cyt1Aa loop β6-αE peptides into the AeDNV genome to improve its mosquitocidal efficiency; protein expression was confirmed using nanoscale liquid chromatography coupled to tandem mass spectrometry (nano LC-MS/MS). Recombinant plasmids were transfected into mosquito C6/36 cell lines, and the expression of specific peptides was detected through RT-PCR. A toxicity bioassay against the first instar Aedes albopictus larvae revealed that the pathogenic activity of recombinant AeDNV was significantly higher and faster than the wild-type (wt) viruses, and mortality increased in a dose-dependent manner. The recombinant viruses were genetically stable and displayed growth phenotype and virus proliferation ability, similar to wild-type AeDNV. Our novel results offer further insights by combining two mosquitocidal pathogens to improve viral toxicity for mosquito control.
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Affiliation(s)
- Khadija Batool
- Department of Pathogen Biology, Institute of Tropical Medicine, School of Public Health, Southern Medical University, Guangzhou 510515, China; (K.B.); (P.L.); (Z.S.); (S.Z.); (W.Y.); (X.J.); (J.G.)
| | - Intikhab Alam
- College of Life Sciences, South China Agricultural University, Guangzhou 510515, China;
| | - Peiwen Liu
- Department of Pathogen Biology, Institute of Tropical Medicine, School of Public Health, Southern Medical University, Guangzhou 510515, China; (K.B.); (P.L.); (Z.S.); (S.Z.); (W.Y.); (X.J.); (J.G.)
| | - Zeng Shu
- Department of Pathogen Biology, Institute of Tropical Medicine, School of Public Health, Southern Medical University, Guangzhou 510515, China; (K.B.); (P.L.); (Z.S.); (S.Z.); (W.Y.); (X.J.); (J.G.)
| | - Siyu Zhao
- Department of Pathogen Biology, Institute of Tropical Medicine, School of Public Health, Southern Medical University, Guangzhou 510515, China; (K.B.); (P.L.); (Z.S.); (S.Z.); (W.Y.); (X.J.); (J.G.)
| | - Wenqiang Yang
- Department of Pathogen Biology, Institute of Tropical Medicine, School of Public Health, Southern Medical University, Guangzhou 510515, China; (K.B.); (P.L.); (Z.S.); (S.Z.); (W.Y.); (X.J.); (J.G.)
| | - Xiao Jie
- Department of Pathogen Biology, Institute of Tropical Medicine, School of Public Health, Southern Medical University, Guangzhou 510515, China; (K.B.); (P.L.); (Z.S.); (S.Z.); (W.Y.); (X.J.); (J.G.)
| | - Jinbao Gu
- Department of Pathogen Biology, Institute of Tropical Medicine, School of Public Health, Southern Medical University, Guangzhou 510515, China; (K.B.); (P.L.); (Z.S.); (S.Z.); (W.Y.); (X.J.); (J.G.)
| | - Xiao-Guang Chen
- Department of Pathogen Biology, Institute of Tropical Medicine, School of Public Health, Southern Medical University, Guangzhou 510515, China; (K.B.); (P.L.); (Z.S.); (S.Z.); (W.Y.); (X.J.); (J.G.)
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Sharma M, Kumar V. Mosquito-larvicidal Binary (BinA/B) proteins for mosquito control programs —advancements, challenges, and possibilities. CURRENT RESEARCH IN INSECT SCIENCE 2022; 2:100028. [PMID: 36003274 PMCID: PMC9387486 DOI: 10.1016/j.cris.2021.100028] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 12/11/2021] [Accepted: 12/14/2021] [Indexed: 11/18/2022]
Abstract
Binary (BinAB) toxin is primarily responsible for the larvicidal action of the WHO recognized mosquito-larvicidal bacterium Lysinibacillus sphaericus. BinAB is a single receptor-specific toxin, active against larvae of Culex and Anopheles, but not Aedes aegypti. The target receptor in Culex is Cqm1 protein, a GPI-anchored amylomaltase located apically in the lipid-rafts of the larval-midgut epithelium. Interaction of the toxin components with the receptor is critical for the larvicidal activity of the toxin. Evidences support the pore formation model for BinAB toxin internalization and the role of toxin-glycan interactions in the endoplasmic reticulum in mediating larval death. Targeted R&D efforts are required to maintain the sustainability and improve efficacy of the eco-friendly BinAB proteins for efficient mosquito control interventions.
The increasing global burden of mosquito-borne diseases require targeted, environmentally friendly, and sustainable approaches for effective vector control without endangering the non-target beneficial insect population. Biological interventions such as biopesticides, Wolbachia-mediated biological controls, or sterile insect techniques are used worldwide. Here we review Binary or BinAB toxin—the mosquito-larvicidal component of WHO-recognized Lysinibacillus sphaericus bacterium employed in mosquito control programs. Binary (BinAB) toxin is primarily responsible for the larvicidal effect of the bacterium. BinAB is a single-receptor-specific toxin and is effective against larvae of Culex and Anopheles, but not against Aedes aegypti. The receptor in Culex, the Cqm1 protein, has been extensively studied. It is a GPI-anchored amylomaltase and is located apically in the lipid rafts of the larval-midgut epithelium. The interaction of the toxin components with the receptor is crucial for the mosquito larvicidal activity of the BinAB toxin. Here we extend support for the pore formation model of BinAB toxin internalization and the role of toxin-glycan interactions in the endoplasmic reticulum in mediating larval death. BinAB is phylogenetically safe for humans, as Cqm1-like protein is not expected in the human proteome. This review aims to initiate targeted R&D efforts, such as applying fusion technologies (chimera of BinA, chemical modification of BinA), for efficient mosquito control interventions. In addition, the review also examines other areas such as bioremediation and cancer therapeutics, in which L. sphaericus is proving useful and showing potential for further development.
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Affiliation(s)
- Mahima Sharma
- Radiation Biology & Health Sciences Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400085, India
| | - Vinay Kumar
- Radiation Biology & Health Sciences Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400085, India
- Correspondence Author: Professor (Retired) Vinay Kumar, Radiation Biology & Health Sciences Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400085, India
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Andreazza F, Oliveira EE, Martins GF. Implications of Sublethal Insecticide Exposure and the Development of Resistance on Mosquito Physiology, Behavior, and Pathogen Transmission. INSECTS 2021; 12:insects12100917. [PMID: 34680686 PMCID: PMC8539869 DOI: 10.3390/insects12100917] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/03/2021] [Accepted: 10/04/2021] [Indexed: 12/31/2022]
Abstract
Simple Summary Mosquitoes are one of the greatest threats to human lives; they transmit a wide range of pathogens, including viruses that cause lethal diseases. Mosquitoes are found in both aquatic (as larvae or pupae) and terrestrial (as adults) environments during their complex life cycle. For decades, insecticides have been systematically used on mosquitoes with the aim to reduce their population. Little is known about how the stress resulting from the exposure of mosquitoes to insecticides impacts the tri-partite relationship between the mosquitoes, their vertebrate hosts, and the pathogens they transmit. In this work, we review existing experimental evidence to obtain a broad picture on the potential effects of the (sub)lethal exposure of hematophagous mosquitoes to different insecticides. We have focused on studies that have advanced our understanding of their physiological and behavioral responses (including the mechanisms behind insecticide resistance) and the spread of pathogens by these vectors—understudied but critically important issues for epidemiology. Studying these exposure-related effects is of paramount importance for predicting how they respond to insecticide exposure and whether this exposure makes them more or less likely to transmit pathogens. Abstract For many decades, insecticides have been used to control mosquito populations in their larval and adult stages. Although changes in the population genetics, physiology, and behavior of mosquitoes exposed to lethal and sublethal doses of insecticides are expected, the relationships between these changes and their abilities to transmit pathogens remain unclear. Thus, we conducted a comprehensive review on the sublethal effects of insecticides and their contributions to insecticide resistance in mosquitoes, with the main focus on pyrethroids. We discuss the direct and acute effects of sublethal concentrations on individuals and populations, the changes in population genetics caused by the selection for resistance after insecticide exposure, and the major mechanisms underlying such resistance. Sublethal exposures negatively impact the individual’s performance by affecting their physiology and behavior and leaving them at a disadvantage when compared to unexposed organisms. How these sublethal effects could change mosquito population sizes and diversity so that pathogen transmission risks can be affected is less clear. Furthermore, despite the beneficial and acute aspects of lethality, exposure to higher insecticide concentrations clearly impacts the population genetics by selecting resistant individuals, which may bring further and complex interactions for mosquitoes, vertebrate hosts, and pathogens. Finally, we raise several hypotheses concerning how the here revised impacts of insecticides on mosquitoes could interplay with vector-mediated pathogens’ transmission.
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Affiliation(s)
- Felipe Andreazza
- Departamento de Entomologia, Universidade Federal de Viçosa, Viçosa 36570-900, MG, Brazil; (F.A.); (E.E.O.)
| | - Eugênio E. Oliveira
- Departamento de Entomologia, Universidade Federal de Viçosa, Viçosa 36570-900, MG, Brazil; (F.A.); (E.E.O.)
| | - Gustavo Ferreira Martins
- Departamento de Biologia Geral, Universidade Federal de Viçosa, Viçosa 36570-900, MG, Brazil
- Correspondence:
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