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Xu G, Wang Z, Bai Y, Crickmore N, Wang K, Hassen AI, Geng L, Shu C, Zhang J. Identification of a biomarker for Bacillus thuringiensis strains with high toxicity against Spodoptera frugiperda based on insecticidal gene linkage analysis. PEST MANAGEMENT SCIENCE 2024; 80:5473-5480. [PMID: 38940437 DOI: 10.1002/ps.8276] [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: 05/21/2024] [Revised: 06/11/2024] [Accepted: 06/13/2024] [Indexed: 06/29/2024]
Abstract
BACKGROUND Bacillus thuringiensis (Bt) is a Gram-positive bacterium that produces various insecticidal proteins used to control insect pests. Spodoptera frugiperda is a global insect pest which causes serious damage to crops, but bio-insecticides currently available to control this pest have limited activity and so new ones are always being sought. In this study we have tested the hypothesis that a biomarker for strain toxicity could be found that would greatly facilitate the identification of new potential products. RESULTS Using genomic sequencing data we constructed a linkage network of insecticidal genes from 1957 Bt genomes and found that four gene families, namely cry1A, cry1I, cry2A and vip3A, showed strong linkage. For 95 strains isolated from soil samples we assayed them for toxicity towards S. frugiperda and for the presence of the above gene families. All of the strains that showed high toxicity also contained a member of the vip3A gene family. Two of them were more toxic than a commercially available strain and genomic sequencing identified a number of potentially novel toxin-encoding genes. CONCLUSIONS The presence of a vip3A gene in the genome of a Bt strain proved to be a strong indicator of toxicity towards S. frugiperda validating this biomarker approach as a strategy for future discovery programs. © 2024 Society of Chemical Industry.
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Affiliation(s)
- Guoli Xu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
- School of Plant Protection, Anhui Agricultural University, Hefei, China
| | - Zeyu Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yuqi Bai
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
- School of Plant Protection, Anhui Agricultural University, Hefei, China
| | - Neil Crickmore
- School of Life Sciences, University of Sussex, Brighton, UK
| | - Kui Wang
- School of Plant Protection, Anhui Agricultural University, Hefei, China
| | - Ahmed Idris Hassen
- Agricultural Research Council-Plant Health and Protection, Pretoria, South Africa
| | - Lili Geng
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Changlong Shu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jie Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
- School of Plant Protection, Anhui Agricultural University, Hefei, China
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2
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Sun Y, Yang P, She M, Lin C, Ye Y, Xu C, Shen Z. A Vip3Af mutant confers high resistance to broad lepidopteran insect pests. PEST MANAGEMENT SCIENCE 2024. [PMID: 39300681 DOI: 10.1002/ps.8402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2024] [Revised: 08/19/2024] [Accepted: 08/21/2024] [Indexed: 09/22/2024]
Abstract
BACKGROUND Vegetative insecticidal proteins (Vip3) from Bacillus thuringiensis (Bt) have been utilized for control of lepidopteran insect pests. The majority of known Vip3 proteins possess exceptional high toxicity against Noctuid insects such as the fall armyworm (FAW, Spodoptera frugiperda), beet armyworm (BAW, Spodoptera exigua) and cotton bollworm (CBW, Helicoverpa armigera), but generally have relatively low or even no activity against some very important pest insects, such as Asian corn borer (ACB, Ostrinia furnacalis), European corn borer (ECB, Ostrinia nubilalis), rice stem borer (RSB, Chilo suppressalis) and oriental armyworm (OAW, Mythimna separata). RESULTS Here, we report mutant Vip3Af with a single amino acid mutation, Vip3Af-T686R, which gains significantly higher insecticidal activity against ACB, OAW and BAW, while retaining high activity against FAW, CBW and RSB. Protein proteolytic activation in vitro showed that the proteolytic activation efficiency of the mutant protein was greater than the wild-type protein in the midgut juice of ACB, OAW and BAW. Transgenic corn expressing this mutant Vip3Af showed high levels of resistance to ACB, OAW, FAW, BAW and CBW. CONCLUSION Our results suggest that Vip3Af may be a superior Vip3A mutant for the development of transgenic crops with resistance to a broad range of lepidopteran pest species. © 2024 Society of Chemical Industry.
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Affiliation(s)
- Yajie Sun
- Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
- Hainan Institute, Zhejiang University, Sanya, China
| | - Pan Yang
- Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Mingjun She
- Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
| | - Chaoyang Lin
- Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
- Hainan Institute, Zhejiang University, Sanya, China
| | - Yuxuan Ye
- Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
- Hainan Institute, Zhejiang University, Sanya, China
| | - Chao Xu
- Ruifeng Biotechnology Co., Ltd, Hangzhou, China
| | - Zhicheng Shen
- Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, China
- Hainan Institute, Zhejiang University, Sanya, China
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3
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Xu W, Sun X, Mi L, Wang K, Gu Z, Wang M, Shu C, Bai X, Zhang J, Geng L. Plants recruit insecticidal bacteria to defend against herbivore attacks. Microbiol Res 2024; 281:127597. [PMID: 38266597 DOI: 10.1016/j.micres.2023.127597] [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: 08/14/2023] [Revised: 12/01/2023] [Accepted: 12/28/2023] [Indexed: 01/26/2024]
Abstract
Pest feeding affects the rhizobacteria community. The rhizomicrobiota activates salicylic acid and jasmonic acid signaling pathways to help plants deal with pest infestation. However, whether plants can recruit special pesticidal microorganisms to deal with attack from herbivores is unclear. A system composed of peanuts and first-instar larvae of Holotrichia parallela were used to analyze whether peanuts truly enrich the insecticidal bacteria after feeding by larvae, and whether inoculation of the enriched bacteria promotes the resistance of plants to herbivore. In this study, high-throughput sequencing of 16 S rRNA gene amplicons was used to demonstrate that infestation of the subterranean pest H. parallela quickly changed the rhizosphere bacterial community structure within 24 h, and the abundance of Enterobacteriaceae, especially Enterobacter, was manifestly enriched. Root feeding induced rhizobacteria to form a more complex co-occurrence network than the control. Rhizosphere bacteria were isolated, and 4 isolates with high toxicity against H. parallela larvae were obtained by random forest analysis. In a back-inoculation experiment using a split-root system, green fluorescent protein (GFP)-labeled Enterobacter sp. IPPBiotE33 was observed to be enriched in uneaten peanut roots. Additionally, supplementation with IPPBiotE33 alleviated the adverse effects of H. parallela on peanuts. Our findings indicated that herbivore infestation could induce plants to assemble bacteria with specific larvicidal activity to address threats.
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Affiliation(s)
- Wenyu Xu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xiaoxiao Sun
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Liang Mi
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China; College of Life Sciences, Northeast Agricultural University, Harbin, China
| | - Kui Wang
- School of Plant Protection, Anhui Agricultural University, Hefei, China
| | - Ziqiong Gu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Meiling Wang
- College of Plant Protection, Shanxi Agricultural University, Taigu, China
| | - Changlong Shu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xi Bai
- College of Life Sciences, Northeast Agricultural University, Harbin, China
| | - Jie Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Lili Geng
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.
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4
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Shao E, Huang H, Yuan J, Yan Y, Ou L, Chen X, Pan X, Guan X, Sha L. N-Terminal α-Helices in Domain I of Bacillus thuringiensis Vip3Aa Play Crucial Roles in Disruption of Liposomal Membrane. Toxins (Basel) 2024; 16:88. [PMID: 38393166 PMCID: PMC10892741 DOI: 10.3390/toxins16020088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2024] [Revised: 01/29/2024] [Accepted: 02/04/2024] [Indexed: 02/25/2024] Open
Abstract
Bacillus thuringiensis Vip3 toxins form a tetrameric structure crucial for their insecticidal activity. Each Vip3Aa monomer comprises five domains. Interaction of the first four α-helices in domain I with the target cellular membrane was proposed to be a key step before pore formation. In this study, four N-terminal α-helix-deleted truncations of Vip3Aa were produced and, it was found that they lost both liposome permeability and insecticidal activity against Spodoptera litura. To further probe the role of domain I in membrane permeation, the full-length domain I and the fragments of N-terminal α-helix-truncated domain I were fused to green fluorescent protein (GFP), respectively. Only the fusion carrying the full-length domain I exhibited permeability against artificial liposomes. In addition, seven Vip3Aa-Cry1Ac fusions were also constructed by combination of α-helices from Vip3Aa domains I and II with the domains II and III of Cry1Ac. Five of the seven combinations were determined to show membrane permeability in artificial liposomes. However, none of the Vip3Aa-Cry1Ac combinations exhibited insecticidal activity due to the significant reduction in proteolytic stability. These results indicated that the N-terminal helix α1 in the Vip3Aa domain I is essential for both insecticidal activity and liposome permeability and that domain I of Vip3Aa preserved a high liposome permeability independently from domains II-V.
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Affiliation(s)
- Ensi Shao
- China National Engineering Research Center of JUNCAO Technology, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (E.S.); (J.Y.); (Y.Y.); (L.O.); (X.C.)
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & Key Laboratory of Biopesticide and Chemical Biology of Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (H.H.); (X.P.); (X.G.)
| | - Hanye Huang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & Key Laboratory of Biopesticide and Chemical Biology of Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (H.H.); (X.P.); (X.G.)
| | - Jin Yuan
- China National Engineering Research Center of JUNCAO Technology, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (E.S.); (J.Y.); (Y.Y.); (L.O.); (X.C.)
| | - Yaqi Yan
- China National Engineering Research Center of JUNCAO Technology, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (E.S.); (J.Y.); (Y.Y.); (L.O.); (X.C.)
| | - Luru Ou
- China National Engineering Research Center of JUNCAO Technology, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (E.S.); (J.Y.); (Y.Y.); (L.O.); (X.C.)
| | - Xiankun Chen
- China National Engineering Research Center of JUNCAO Technology, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (E.S.); (J.Y.); (Y.Y.); (L.O.); (X.C.)
| | - Xiaohong Pan
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & Key Laboratory of Biopesticide and Chemical Biology of Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (H.H.); (X.P.); (X.G.)
| | - Xiong Guan
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & Key Laboratory of Biopesticide and Chemical Biology of Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (H.H.); (X.P.); (X.G.)
| | - Li Sha
- China National Engineering Research Center of JUNCAO Technology, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (E.S.); (J.Y.); (Y.Y.); (L.O.); (X.C.)
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & Key Laboratory of Biopesticide and Chemical Biology of Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (H.H.); (X.P.); (X.G.)
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5
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He X, Yang Y, Soberón M, Bravo A, Zhang L, Zhang J, Wang Z. Bacillus thuringiensis Cry9Aa Insecticidal Protein Domain I Helices α3 and α4 Are Two Core Regions Involved in Oligomerization and Toxicity. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:1321-1329. [PMID: 38175929 DOI: 10.1021/acs.jafc.3c08070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2024]
Abstract
Bacillus thuringiensis Cry9 proteins show high insecticidal activity against different lepidopteran pests. Cry9 could be a valuable alternative to Cry1 proteins because it showed a synergistic effect with no cross-resistance. However, the pore-formation region of the Cry9 proteins is still unclear. In this study, nine mutations of certain Cry9Aa helices α3 and α4 residues resulted in a complete loss of insecticidal activity against the rice pest Chilo suppressalis; however, the protein stability and receptor binding ability of these mutants were not affected. Among these mutants, Cry9Aa-D121R, Cry9Aa-D125R, Cry9Aa-D163R, Cry9Aa-E165R, and Cry9Aa-D167R are unable to form oligomers in vitro, while the oligomers formed by Cry9Aa-R156D, Cry9Aa-R158D, and Cry9Aa-R160D are unstable and failed to insert into the membrane. These data confirmed that helices α3 and α4 of Cry9Aa are involved in oligomerization, membrane insertion, and toxicity. The knowledge of Cry9 pore-forming action may promote its application as an alternative to Cry1 insecticidal proteins.
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Affiliation(s)
- Xiang He
- Anhui Province Engineering Laboratory for Green Pesticide Development and Application, School of Plant Protection, Anhui Agricultural University, Hefei, Anhui Province 230036, China
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Yanchao Yang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Mario Soberón
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Apdo. Postal 510-3, Morelos 62250, Mexico
| | - Alejandra Bravo
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Apdo. Postal 510-3, Morelos 62250, Mexico
| | - Lihong Zhang
- Anhui Province Engineering Laboratory for Green Pesticide Development and Application, School of Plant Protection, Anhui Agricultural University, Hefei, Anhui Province 230036, China
| | - Jie Zhang
- Anhui Province Engineering Laboratory for Green Pesticide Development and Application, School of Plant Protection, Anhui Agricultural University, Hefei, Anhui Province 230036, China
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Zeyu Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
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6
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Wang Z, Yang Y, Li S, Ma W, Wang K, Soberón M, Yan S, Shen J, Francis F, Bravo A, Zhang J. JAK/STAT signaling regulated intestinal regeneration defends insect pests against pore-forming toxins produced by Bacillus thuringiensis. PLoS Pathog 2024; 20:e1011823. [PMID: 38236820 PMCID: PMC10796011 DOI: 10.1371/journal.ppat.1011823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 11/13/2023] [Indexed: 01/22/2024] Open
Abstract
A variety of coordinated host-cell responses are activated as defense mechanisms against pore-forming toxins (PFTs). Bacillus thuringiensis (Bt) is a worldwide used biopesticide whose efficacy and precise application methods limits its use to replace synthetic pesticides in agricultural settings. Here, we analyzed the intestinal defense mechanisms of two lepidopteran insect pests after intoxication with sublethal dose of Bt PFTs to find out potential functional genes. We show that larval intestinal epithelium was initially damaged by the PFTs and that larval survival was observed after intestinal epithelium regeneration. Further analyses showed that the intestinal regeneration caused by Cry9A protein is regulated through c-Jun NH (2) terminal kinase (JNK) and Janus tyrosine kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathways. JAK/STAT signaling regulates intestinal regeneration through proliferation and differentiation of intestinal stem cells to defend three different Bt proteins including Cry9A, Cry1F or Vip3A in both insect pests, Chilo suppressalis and Spodoptera frugiperda. Consequently, a nano-biopesticide was designed to improve pesticidal efficacy based on the combination of Stat double stranded RNA (dsRNA)-nanoparticles and Bt strain. This formulation controlled insect pests with better effect suggesting its potential use to reduce the use of synthetic pesticides in agricultural settings for pest control.
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Affiliation(s)
- Zeyu Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yanchao Yang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
- Department of Functional and Evolutionary Entomology, Gembloux Agro-Bio Tech, University of Liège, Gembloux, Belgium
| | - Sirui Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Weihua Ma
- National Key Laboratory of Crop Genetic Improvement, National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan, China
| | - Kui Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Mario Soberón
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, Mexico
| | - Shuo Yan
- Department of Plant Biosecurity and MOA Key Laboratory of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, China
| | - Jie Shen
- Department of Plant Biosecurity and MOA Key Laboratory of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, China
| | - Frederic Francis
- Department of Functional and Evolutionary Entomology, Gembloux Agro-Bio Tech, University of Liège, Gembloux, Belgium
| | - Alejandra Bravo
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, Mexico
| | - Jie Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
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7
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Hou X, Li M, Mao C, Jiang L, Zhang W, Li M, Geng X, Li X, Liu S, Yang G, Zhou J, Fang Y, Cai J. Domain III β4- β5 Loop and β14- β15 Loop of Bacillus thuringiensis Vip3Aa Are Involved in Receptor Binding and Toxicity. Toxins (Basel) 2024; 16:23. [PMID: 38251240 PMCID: PMC10820090 DOI: 10.3390/toxins16010023] [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: 11/17/2023] [Revised: 12/23/2023] [Accepted: 12/30/2023] [Indexed: 01/23/2024] Open
Abstract
Vip3Aa, secreted by Bacillus thuringiensis, is effective at controlling major agricultural pests such as Spodoptera frugiperda. However, to control Vip3Aa resistance evolved in the field by different lepidoptera species, an in-depth study of sequence--structure--activity relationships is necessary to design new Vip3Aa variants. In this study, the four specific loops (β4-β5 loop, β9-β10 loop, β12-β13 loop, and β14-β15 loop) in domain III were selected and four loop mutants were constructed by replacing all residues in each specific loop with alanine. We obtained soluble proteins for three of the loop mutants, excluding the β9-β10 loop. These loop mutants have been characterized by toxicity bioassays against S. frugiperda, proteolytic processing, and receptor binding. These results indicate that the β4-β5 loop and β14-β15 loop are involved in receptor binding and Vip3Aa toxicity. Based on this, we constructed numerous mutants and obtained three single mutants (Vip3Aa-S366T, Vip3Aa-S366L, and Vip3Aa-R501A) that exhibited significantly increased toxicity of 2.61-fold, 3.39-fold, and 2.51-fold, respectively. Compared to Vip3Aa, the receptor affinity of Vip3Aa-S366T and Vip3Aa-S366L was significantly enhanced. Furthermore, we also analyzed and aligned the three-dimensional structures of the mutants and Vip3Aa. In summary, these results indicate that the loops in domain III have the potential to be targeted to enhance the insecticidal toxicity of the Vip3Aa protein.
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Affiliation(s)
- Xiaoyue Hou
- Jiangsu Key Laboratory of Marine Bioresources and Environment, Jiangsu Ocean University, Lianyungang 222005, China; (X.H.); (S.L.); (G.Y.)
- Co–Innovation Center of Jiangsu Marine Bio–Industry Technology, Jiangsu Ocean University, Lianyungang 222005, China
- Jiangsu Marine Resources Development Research Institute, Jiangsu Ocean University, Lianyungang 222005, China
- College of Marine Food and Bioengineering, Jiangsu Ocean University, Lianyungang 222005, China; (M.L.); (C.M.); (L.J.); (W.Z.); (M.L.); (X.G.); (X.L.)
- College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Mengjiao Li
- College of Marine Food and Bioengineering, Jiangsu Ocean University, Lianyungang 222005, China; (M.L.); (C.M.); (L.J.); (W.Z.); (M.L.); (X.G.); (X.L.)
| | - Chengjuan Mao
- College of Marine Food and Bioengineering, Jiangsu Ocean University, Lianyungang 222005, China; (M.L.); (C.M.); (L.J.); (W.Z.); (M.L.); (X.G.); (X.L.)
| | - Lei Jiang
- College of Marine Food and Bioengineering, Jiangsu Ocean University, Lianyungang 222005, China; (M.L.); (C.M.); (L.J.); (W.Z.); (M.L.); (X.G.); (X.L.)
| | - Wen Zhang
- College of Marine Food and Bioengineering, Jiangsu Ocean University, Lianyungang 222005, China; (M.L.); (C.M.); (L.J.); (W.Z.); (M.L.); (X.G.); (X.L.)
| | - Mengying Li
- College of Marine Food and Bioengineering, Jiangsu Ocean University, Lianyungang 222005, China; (M.L.); (C.M.); (L.J.); (W.Z.); (M.L.); (X.G.); (X.L.)
| | - Xiaomeng Geng
- College of Marine Food and Bioengineering, Jiangsu Ocean University, Lianyungang 222005, China; (M.L.); (C.M.); (L.J.); (W.Z.); (M.L.); (X.G.); (X.L.)
| | - Xin Li
- College of Marine Food and Bioengineering, Jiangsu Ocean University, Lianyungang 222005, China; (M.L.); (C.M.); (L.J.); (W.Z.); (M.L.); (X.G.); (X.L.)
| | - Shu Liu
- Jiangsu Key Laboratory of Marine Bioresources and Environment, Jiangsu Ocean University, Lianyungang 222005, China; (X.H.); (S.L.); (G.Y.)
- Co–Innovation Center of Jiangsu Marine Bio–Industry Technology, Jiangsu Ocean University, Lianyungang 222005, China
- Jiangsu Marine Resources Development Research Institute, Jiangsu Ocean University, Lianyungang 222005, China
- College of Marine Food and Bioengineering, Jiangsu Ocean University, Lianyungang 222005, China; (M.L.); (C.M.); (L.J.); (W.Z.); (M.L.); (X.G.); (X.L.)
| | - Guang Yang
- Jiangsu Key Laboratory of Marine Bioresources and Environment, Jiangsu Ocean University, Lianyungang 222005, China; (X.H.); (S.L.); (G.Y.)
- Co–Innovation Center of Jiangsu Marine Bio–Industry Technology, Jiangsu Ocean University, Lianyungang 222005, China
- Jiangsu Marine Resources Development Research Institute, Jiangsu Ocean University, Lianyungang 222005, China
- College of Marine Food and Bioengineering, Jiangsu Ocean University, Lianyungang 222005, China; (M.L.); (C.M.); (L.J.); (W.Z.); (M.L.); (X.G.); (X.L.)
| | - Jing Zhou
- Lianyungang City Quality Technology Comprehensive Inspection and Quality Inspection Center, Lianyungang 222346, China;
| | - Yaowei Fang
- Jiangsu Key Laboratory of Marine Bioresources and Environment, Jiangsu Ocean University, Lianyungang 222005, China; (X.H.); (S.L.); (G.Y.)
- Co–Innovation Center of Jiangsu Marine Bio–Industry Technology, Jiangsu Ocean University, Lianyungang 222005, China
- Jiangsu Marine Resources Development Research Institute, Jiangsu Ocean University, Lianyungang 222005, China
- College of Marine Food and Bioengineering, Jiangsu Ocean University, Lianyungang 222005, China; (M.L.); (C.M.); (L.J.); (W.Z.); (M.L.); (X.G.); (X.L.)
| | - Jun Cai
- College of Life Sciences, Nankai University, Tianjin 300071, China
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8
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Xue B, Wang M, Wang Z, Shu C, Geng L, Zhang J. Analysis of Synergism between Extracellular Polysaccharide from Bacillus thuringensis subsp. kurstaki HD270 and Insecticidal Proteins. Toxins (Basel) 2023; 15:590. [PMID: 37888621 PMCID: PMC10610938 DOI: 10.3390/toxins15100590] [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: 08/24/2023] [Revised: 09/22/2023] [Accepted: 09/26/2023] [Indexed: 10/28/2023] Open
Abstract
Bacillus thuringiensis (Bt) is the most widely used biopesticide worldwide and can produce several insecticidal crystal proteins and vegetative insecticidal proteins (Vips) at different growth stages. In our previous study, extracellular polysaccharides (EPSs) of Bt strain HD270 were found to enhance the insecticidal activity of Cry1Ac protoxin against Plutella xylostella (L.) and promote the binding of Cry1Ac to the intestinal brush border membrane vesicles (BBMVs). Whether the synergistic activity of Bt EPSs is common to other Cry1-type or Vip proteins is unclear, as is the potential synergistic mechanism. In this study, crude EPS-HD270 was found to increase the toxicity of Cry1-type toxins and Vip3Aa11 against different lepidopteran pests by approximately 2-fold. The purified EPS-HD270 also possessed synergistic activity against the toxicity of Cry1Ac and Vip3Aa11 against Spodoptera frugiperda (J.E. Smith) and Helicoverpa armigera (Hübner). Furthermore, we found that EPS-HD270 had a strong binding ability with Vip3Aa11 and promoted the binding of Vip3Aa11 to the BBMVs of H. armigera and S. frugiperda. Bt EPS-HD270 also protected Vip3Aa11 from proteolytic processing in larval midgut juice. Bt EPSs had universal synergistic effects on Cry1-type or Vip toxins against S. frugiperda and H. armigera. Bt EPS-HD270 exhibited synergistic activity with Vip3Aa through promotion of binding to BBMVs and protection from digestion by midgut protease. The results indicated that synergistic activity with Bt toxins was an important function of Bt EPSs, which was very different from other Bacillus spp.
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Affiliation(s)
- Bai Xue
- College of Life Sciences, Northeast Agricultural University, Harbin 150030, China
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Meiling Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Zeyu Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Changlong Shu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Lili Geng
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Jie Zhang
- College of Life Sciences, Northeast Agricultural University, Harbin 150030, China
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
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