Browse
Submit Data
Databases
API
Help

Dataset Information

26 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Toxicity analysis of N- and C-terminus-deleted vegetative insecticidal protein from Bacillus thuringiensis.

ABSTRACT: A vegetative insecticidal protein (VIP)-encoding gene from a local isolate of Bacillus thuringiensis has been cloned, sequenced, and expressed in Escherichia coli. The expressed protein shows insecticidal activity against several lepidopteran pests but is ineffective against Agrotis ipsilon. Comparison of the amino acid sequence with those of reported VIPs revealed a few differences. Analysis of insecticidal activity with N- and C-terminus deletion mutants suggests a differential mode of action of VIP against different pests.

SUBMITTER: Selvapandiyan A

PROVIDER: S-EPMC93383 | biostudies-literature | 2001 Dec

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Toxicity analysis of N- and C-terminus-deleted vegetative insecticidal protein from Bacillus thuringiensis.

Selvapandiyan A A Arora N N Rajagopal R R Jalali S K SK Venkatesan T T Singh S P SP Bhatnagar R K RK

Applied and environmental microbiology 20011201 12

A vegetative insecticidal protein (VIP)-encoding gene from a local isolate of Bacillus thuringiensis has been cloned, sequenced, and expressed in Escherichia coli. The expressed protein shows insecticidal activity against several lepidopteran pests but is ineffective against Agrotis ipsilon. Comparison of the amino acid sequence with those of reported VIPs revealed a few differences. Analysis of insecticidal activity with N- and C-terminus deletion mutants suggests a differential mode of action ...[more]

PMID: 11722946

Similar Datasets

Vip3C, a novel class of vegetative insecticidal proteins from Bacillus thuringiensis.

Project description:Three vip3 genes were identified in two Bacillus thuringiensis Spanish collections. Sequence analysis revealed a novel Vip3 protein class (Vip3C). Preliminary bioassays of larvae from 10 different lepidopteran species indicated that Vip3Ca3 caused more than 70% mortality in four species after 10 days at 4 ?g/cm(2).

| S-EPMC3457495 | biostudies-literature

Vegetative Insecticidal Protein Vip3Aa Is Transported via Membrane Vesicles in Bacillus thuringiensis BMB171.

Project description:Vegetative insecticidal protein Vip3Aa, secreted by many Bacillus thuringiensis (Bt) strains during the vegetative growth stage, represents the second-generation insecticidal toxin. In recent years, significant progress has been made on its structure and action mechanism. However, how it is translocated across the cytoplasmic membrane into the environment remains a mystery. This work demonstrates that Vip3Aa is not secreted by the General Secretion (Sec) System. To reveal the secretory pathway of Vip3A, we purified the membrane vesicles (MVs) of B. thuringiensis BMB171 and observed by TEM. The size of MVs was determined by the dynamic light scattering method, and their diameter was approximately 40-200 nm, which is consistent with the vesicles in Gram-negative bacteria. Moreover, Vip3A could be detected in the purified MVs by Western blot, and immunoelectron microscopy reveals Vip3A antibody-coated gold particles located in the MVs. After deleting its signal peptide, chitinase B (ChiB) failed to be secreted. However, the recombinant ChiB, whose signal peptide was substituted with the N-terminal 39 amino acids from Vip3A, was secreted successfully through MVs. Thus, this sequence is proposed as the signal region responsible for vesicle transport. Together, our results revealed for the first time that Vip3Aa is transported to the medium via MVs.

| S-EPMC9319297 | biostudies-literature

Interaction of Bacillus thuringiensis vegetative insecticidal protein with ribosomal S2 protein triggers larvicidal activity in Spodoptera frugiperda.

Project description:Vegetative insecticidal protein (Vip3A) is synthesized as an extracellular insecticidal toxin by certain strains of Bacillus thuringiensis. Vip3A is active against several lepidopteran pests of crops. Polyphagous pest, Spodoptera frugiperda, and its cell line Sf21 are sensitive for lyses to Vip3A. Screening of cDNA library prepared from Sf21 cells through yeast two-hybrid system with Vip3A as bait identified ribosomal protein S2 as a toxicity-mediating interacting partner protein. The Vip3A-ribosomal-S2 protein interaction was validated by in vitro pulldown assays and by RNA interference-induced knockdown experiments. Knockdown of expression of S2 protein in Sf21 cells resulted in reduced toxicity of the Vip3A protein. These observations were further extended to adult fifth-instar larvae of Spodoptera litura. Knockdown of S2 expression by injecting corresponding double-stranded RNA resulted in reduced mortality of larvae to Vip3A toxin. Intracellular visualization of S2 protein and Vip3A through confocal microscopy revealed their interaction and localization in cytoplasm and surface of Sf21 cells.

| S-EPMC2976263 | biostudies-literature

Vegetative Insecticidal Protein (Vip): A Potential Contender From Bacillus thuringiensis for Efficient Management of Various Detrimental Agricultural Pests.

Project description:Bacillus thuringiensis (Bt) bacterium is found in various ecological habitats, and has natural entomo-pesticidal properties, due to the production of crystalline and soluble proteins during different growth phases. In addition to Cry and Cyt proteins, this bacterium also produces Vegetative insecticidal protein (Vip) during its vegetative growth phase, which is considered an excellent toxic candidate because of the difference in sequence homology and receptor sites from Cry proteins. Vip proteins are referred as second-generation insecticidal proteins, which can be used either alone or in complementarity with Cry proteins for the management of various detrimental pests. Among these Vip proteins, Vip1 and Vip2 act as binary toxins and have toxicity toward pests belonging to Hemiptera and Coleoptera orders, whereas the most important Vip3 proteins have insecticidal activity against Lepidopteran pests. These Vip3 proteins are similar to Cry proteins in terms of toxicity potential against susceptible insects. They are reported to be toxic toward pests, which can't be controlled with Cry proteins. The Vip3 proteins have been successfully pyramided along with Cry proteins in transgenic rice, corn, and cotton to combat resistant pest populations. This review provides detailed information about the history and importance of Vip proteins, their types, structure, newly identified specific receptors, and action mechanism of this specific class of proteins. Various studies conducted on Vip proteins all over the world and the current status have been discussed. This review will give insights into the significance of Vip proteins as alternative promising candidate toxic proteins from Bt for the management of pests in most sustainable manner.

| S-EPMC8158940 | biostudies-literature

Vip3A, a novel Bacillus thuringiensis vegetative insecticidal protein with a wide spectrum of activities against lepidopteran insects.

Project description:A novel vegetative insecticidal gene, vip3A(a), whose gene product shows activity against lepidopteran insect larvae including black cutworm (Agrotis ipsilon), fall armyworm (Spodoptera frugiperda), beet armyworm (Spodoptera exigua), tobacco budworm (Heliothis virescens), and corn earworm (Helicoverpa zea) has been isolated from Bacillus thuringiensis strain AB88. VIP3-insecticidal gene homologues have been detected in approximately 15% of Bacillus strains analyzed. The sequence of the vip3A(b) gene, a homologue of vip3A(a) isolated from B. thuringiensis strain AB424 is also reported. Vip3A(a) and (b) proteins confer upon Escherichia coli insecticidal activity against the lepidopteran insect larvae mentioned above. The sequence of the gene predicts a 791-amino acid (88.5 kDa) protein that contains no homology with known proteins. Vip3A insecticidal proteins are secreted without N-terminal processing. Unlike the B. thuringiensis 5-endotoxins, whose expression is restricted to sporulation, Vip3A insecticidal proteins are expressed in the vegetative stage of growth starting at mid-log phase as well as during sporulation. Vip3A represents a novel class of proteins insecticidal to lepidopteran insect larvae.

| S-EPMC39256 | biostudies-other

Vegetative insecticidal protein (Vip3A) production by Bacillus thuringiensis Bt294 and its efficacy against Lepidopteran pests (Spodoptera exigua).

Project description:A vegetative insecticidal protein, Vip3A, is highly active against lepidopteran pests, which are the most important pests in most tropical countries. An important aspect of the successful commercial production of this bacterial insecticide is the development of bacterial culture media that maximize the titres of this protein and cost reduction. This study aimed to investigate and optimize Vip3A production by Bacillus thuringiensis Bt294 using statistical methods and 3-step sequential approaches. The experimental design showed that the production of Vip3A was maximized to 300 mg/L when the bacterium was cultivated in medium composed of 5.05 g/L glycerol, 49.17 g/L soytone, 30.05 g/L casein hydrolysate, 1.99 g/L CaCl2.2H2O, 7.5 mg/L CuSO4, 15 mg/L MnSO4.H2O, 9.4 g/L K2HPO4, 2.2 g/L KH2PO4, 0.2 g/L MgSO4.7H2O, 5 g/L yeast extract, 2.5 mg/L NiCl2.6H2O and 3 mL/L vitamin solution. B. thuringiensis Bt294 Vip3A toxin was highly toxic to Spodoptera exigua with LC50 values of 187.1 ng/cm2 at 7 days. This result demonstrated that a high titre of Vip3A produced by B. thuringiensis Bt294 will be useful as a biological control agent. This optimization will allow production to be scaled up for commercial production in the future.

| S-EPMC10509655 | biostudies-literature

Structural and functional insights into the first Bacillus thuringiensis vegetative insecticidal protein of the Vpb4 fold, active against western corn rootworm.

Project description:The western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, is a major maize pest in the United States causing significant economic loss. The emergence of field-evolved resistant WCR to Bacillus thuringiensis (Bt) traits has prompted the need to discover and deploy new insecticidal proteins in transgenic maize. In the current study we determined the crystal structure and mode of action (MOA) of the Vpb4Da2 protein (formerly known as Vip4Da2) from Bt, the first identified insecticidal Vpb4 protein with commercial level control against WCR. The Vpb4Da2 structure exhibits a six-domain architecture mainly comprised of antiparallel β-sheets organized into β-sandwich layers. The amino-terminal domains 1-3 of the protein share structural homology with the protective antigen (PA) PA14 domain and encompass a long β-pore forming loop as in the clostridial binary-toxB module. Domains 5 and 6 at the carboxyl-terminal half of Vpb4Da2 are unique as this extension is not observed in PA or any other structurally-related protein other than Vpb4 homologs. These unique Vpb4 domains adopt the topologies of carbohydrate-binding modules known to participate in receptor-recognition. Functional assessment of Vpb4Da2 suggests that domains 4-6 comprise the WCR receptor binding region and are key in conferring the observed insecticidal activity against WCR. The current structural analysis was complemented by in vitro and in vivo characterizations, including immuno-histochemistry, demonstrating that Vpb4Da2 follows a MOA that is consistent with well-characterized 3-domain Bt insecticidal proteins despite significant structural differences.

| S-EPMC8687597 | biostudies-literature

Scavenger receptor-C acts as a receptor for Bacillus thuringiensis vegetative insecticidal protein Vip3Aa and mediates the internalization of Vip3Aa via endocytosis.

Project description:The vegetative insecticidal proteins (Vip), secreted by many Bacillus thuringiensis strains during their vegetative growth stage, are genetically distinct from known insecticidal crystal proteins (ICPs) and represent the second-generation insecticidal toxins. Compared with ICPs, the insecticidal mechanisms of Vip toxins are poorly understood. In particular, there has been no report of a definite receptor of Vip toxins to date. In the present study, we identified the scavenger receptor class C like protein (Sf-SR-C) from the Spodoptera frugiperda (Sf9) cells membrane proteins that bind to the biotin labeled Vip3Aa, via the affinity magnetic bead method coupled with HPLC-MS/MS. We then certified Vip3Aa protoxin could interact with Sf-SR-C in vitro and ex vivo. In addition, downregulation of SR-C expression in Sf9 cells and Spodoptera exigua larvae midgut reduced the toxicity of Vip3Aa to them. Coincidently, heterologous expression of Sf-SR-C in transgenic Drosophila midgut significantly enhanced the virulence of Vip3Aa to the Drosophila larvae. Moreover, the complement control protein domain and MAM domain of Sf-SR-C are involved in the interaction with Vip3Aa protoxin. Furthermore, endocytosis of Vip3Aa mediated by Sf-SR-C correlates with its insecticidal activity. Our results confirmed for the first time that Sf-SR-C acts as a receptor for Vip3Aa protoxin and provides an insight into the mode of action of Vip3Aa that will significantly facilitate the study of its insecticidal mechanism and application.

| S-EPMC6191154 | biostudies-literature

Molecular architecture and activation of the insecticidal protein Vip3Aa from Bacillus thuringiensis.

Project description:Bacillus thuringiensis Vip3 (Vegetative Insecticidal Protein 3) toxins are widely used in biotech crops to control Lepidopteran pests. These proteins are produced as inactive protoxins that need to be activated by midgut proteases to trigger cell death. However, little is known about their three-dimensional organization and activation mechanism at the molecular level. Here, we have determined the structures of the protoxin and the protease-activated state of Vip3Aa at 2.9 Å using cryo-electron microscopy. The reconstructions show that the protoxin assembles into a pyramid-shaped tetramer with the C-terminal domains exposed to the solvent and the N-terminal region folded into a spring-loaded apex that, after protease activation, drastically remodels into an extended needle by a mechanism akin to that of influenza haemagglutinin. These results provide the molecular basis for Vip3 activation and function, and serves as a strong foundation for the development of more efficient insecticidal proteins.

| S-EPMC7414852 | biostudies-literature

Evolution of Bacillus thuringiensis Cry toxins insecticidal activity.

Project description:Insecticidal Cry proteins produced by Bacillus thuringiensis are use worldwide in transgenic crops for efficient pest control. Among the family of Cry toxins, the three domain Cry family is the better characterized regarding their natural evolution leading to a large number of Cry proteins with similar structure, mode of action but different insect specificity. Also, this group is the better characterized regarding the study of their mode of action and the molecular basis of insect specificity. In this review we discuss how Cry toxins have evolved insect specificity in nature and analyse several cases of improvement of Cry toxin action by genetic engineering, some of these examples are currently used in transgenic crops. We believe that the success in the improvement of insecticidal activity by genetic evolution of Cry toxins will depend on the knowledge of the rate-limiting steps of Cry toxicity in different insect pests, the mapping of the specificity binding regions in the Cry toxins, as well as the improvement of mutagenesis strategies and selection procedures.

| S-EPMC3815381 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data