title: Isolation, characterization and expression of a novel vegetative insecticidal protein gene of Bacillus thuringiensis.
abstract: Twenty-four serovars of Bacillus thuringiensis (Bt) were screened by polymerase chain reaction to detect the presence of vegetative insecticidal protein gene (vip)-like sequences by using vip3Aa1-specific primers. vip-like gene sequences were identified in eight serovars. These genes were cloned and sequenced. The deduced amino acid sequence of the vip3Aa14 gene from Bacillus thuringiensis tolworthi showed considerable differences as compared to those of Vips reported so far. The vip3Aa14 gene from Bt tolwarthi was expressed in Escherichia coli using expression vector pET29a. The expressed Vip3Aa14 protein was found in cytosolic supernatant as well as pellet fraction, but the protein was more abundant in the cytosolic supernatant fraction. Both full-length and truncated (devoid of signal sequence) Vips were highly toxic to the larvae of Spodoptera litura and Plutella xylostella. Truncation of Vip3Aa14 protein at N-terminus did not affect its insecticidal activity.
authors.affiliation: National Research Center for Plant Biotechnology, Indian Agricultural Research Institute, New Delhi 110 012, India.
authors.forename: Ritu
authors.initials: R
authors.lastname: Bhalla
authors.forename: Monika
authors.initials: M
authors.lastname: Dalal
authors.forename: Siva K
authors.initials: SK
authors.lastname: Panguluri
authors.forename: Borra
authors.initials: B
authors.lastname: Jagadish
authors.forename: Ajin D
authors.initials: AD
authors.lastname: Mandaokar
authors.forename: A K
authors.initials: AK
authors.lastname: Singh
authors.forename: Polumetla A
authors.initials: PA
authors.lastname: Kumar
mesh_terms: D000818:Animals; D001413:Bacillus thuringiensis / Q000145:classification / Q000235:genetics / Q000254:growth & development*; D001426:Bacterial Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism / Q000633:toxicity; D001427:Bacterial Toxins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism / Q000633:toxicity; D001681:Biological Assay; D004731:Endotoxins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism / Q000633:toxicity; D007814:Larva / Q000254:growth & development; D008969:Molecular Sequence Data; D009036:Moths / Q000254:growth & development; D010572:Pest Control, Biological; D018515:Plant Leaves / Q000737:chemistry; D017422:Sequence Analysis, DNA; D018411:Spodoptera / Q000254:growth & development
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004731:Endotoxins