title: Cloning, characterization, and expression of a new cry1Ab gene from DOR Bt-1, an indigenous isolate of Bacillus thuringiensis.
abstract: A new cry1Ab gene was cloned from the promising local isolate, DOR Bt-1, a Bacillus thuringiensis strain isolated from castor semilooper (Achaea janata L.) cadavers from castor bean (Ricinus communis L.) field. The nucleotide sequence of the cloned cry1Ab gene indicated that the open reading frame consisted of 3,465 bases encoding a protein of 1,155 amino acid residues with an estimated molecular weight of 130 kDa. Homology comparisons revealed that the deduced amino acid sequence of cry1Ab had a variation of seven amino acid residues compared to those of the known Cry1Ab proteins in the NCBI database and this gene has been designated as cry1Ab26 by the B. thuringiensis δ-endotoxin Nomenclature Committee. cry1Ab26 was cloned into pET 29a(+) vector and expressed in E. coli strain BL21 (DE3) under the control of T7 promoter with IPTG induction. ELISA, SDS-PAGE, and Western blot analysis confirmed the expression of 130-kDa protein. Insect bioassays with neonate larvae of Helicoverpa armigera showed that the partially purified Cry1Ab26 caused 97 % mortality within 5 days of feeding.
authors.affiliation: Directorate of Oilseeds Research, ICAR, Rajendranagar, Hyderabad 500030, India. prathapredd@gmail.com
authors.forename: V Prathap
authors.initials: VP
authors.lastname: Reddy
authors.forename: N Narasimha
authors.initials: NN
authors.lastname: Rao
authors.forename: P S Vimala
authors.initials: PS
authors.lastname: Devi
authors.forename: S
authors.initials: S
authors.lastname: Sivaramakrishnan
authors.forename: M Lakshmi
authors.initials: ML
authors.lastname: Narasu
authors.forename: V Dinesh
authors.initials: VD
authors.lastname: Kumar
mesh_terms: D000818:Animals; D001413:Bacillus thuringiensis / Q000235:genetics*; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D015153:Blotting, Western; D003001:Cloning, Molecular; D004591:Electrophoresis, Polyacrylamide Gel; D004731:Endotoxins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D004797:Enzyme-Linked Immunosorbent Assay; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D006460:Hemolysin Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D007814:Larva / Q000187:drug effects; D009036:Moths; D010572:Pest Control, Biological; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D004731:Endotoxins; D006460:Hemolysin Proteins; D011994:Recombinant Proteins; C030956:insecticidal crystal protein, Bacillus Thuringiensis