Cloning and characterization of an insecticidal crystal protein gene from Bacillus thuringiensis subspecies kenyae

Journal of genetics

Nivedita P. Khairnar²  S. K. Mahajan¹  Manjula Mathur²  Hari S. Misra1²  Remesh S. Hire¹  T. K. Dongre¹  N. Vijayalakshmi¹ 

[1] Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Centre, Mumbai 400 085, India$$;Molecular Biology and Agriculture Division, Bhabha Atomic Research Centre, Mumbai 400 085, India$$

关键词: insecticidal protein;    dipteran;    Bacillus thuringiensis var. kenyae.;   

DOI  :  

学科分类：生物科学（综合）

来源: Indian Academy of Sciences

【 摘 要 】

A sporulating culture of Bacillus thuringiensis subsp. kenyae strain HD549 is toxic to larvae of lepidopteran insect species such as Spodoptera litura, Helicoverpa armigera and Phthorimaea operculella, and a dipteran insect, Culex fatigans. A 1.9-kb DNA fragment, PCR-amplified from HD549 using cryII-gene-specific primers, was cloned and expressed in E. coli. The recombinant protein produced 92% mortality in first-instar larvae of Spodoptera litura and 86% inhibition of adult emergence in Phthorimaea operculella, but showed very low toxicity against Helicoverpa armigera, and lower mortality against third-instar larvae of dipteran insects Culex fatigans, Anopheles stephensi and Aedes aegypti. The sequence of the cloned crystal protein gene showed almost complete homology with a mosquitocidal toxin gene from Bacillus thuringiensis var. kurstaki, with only five mutations scattered in different regions. Amino acid alignment with different insecticidal crystal proteins using the MUTALIN program suggested presence of the conserved block 3 region in the sequence of this protein. A mutation in codon 409 of this gene that changes a highly conserved phenylalanine residue to serine lies in this block.

【 授权许可】

Unknown