Prevalence of cry2-type genes in Bacillus thuringiensis isolates recovered from diverse habitats in India and isolation of a novel cry2Af2 gene toxic to Helicoverpa armigera (cotton boll worm).
Insecticidal cry and vip genes from Bacillus thuringiensis (Bt) have been used for control of lepidopteran insects in transgenic crops. However, novel genes are required for gene pyramiding to delay evolution of resistance to the currently deployed genes. Two PCR-based techniques were employed for screening of cry2-type genes in 129 Bt isolates from diverse habitats in India and 27 known Bt strains. cry2Ab-type genes were more prevalent than cry2Aa- and cry2Ac-type genes. Correlation between source of isolates and abundance of cry2-type genes was not observed. Full-length cry2A-type genes were amplified by PCR from 9 Bt isolates and 4 Bt strains. The genes from Bt isolates SK-758 from Sorghum grain dust and SK-793 from Chilli seeds warehouse, Andhra Pradesh, were cloned and sequenced. The gene from SK-758 (NCBI GenBank accession No. GQ866915) was novel, while that from SK-793 (NCBI GenBank accession No. GQ866914) was identical to the cry2Ab1 gene. The Bacillus thuringiensis Nomenclature Committee ( http://www.lifesci.sussex.ac.uk/home/Neil_Crickmore/Bt/toxins2.html ) named these genes cry2Af2 and cry2Ab16, respectively. The cry2Af2 gene was expressed in Escherichia coli and found to be toxic towards Helicoverpa armigera. The cry2Af2 gene will be useful for pyramiding in transgenic crops.
Indian Council of Agricultural Research (ICAR) - National Research Centre on Plant Biotechnology, Indian Agricultural Research Institute Campus, New Delhi 110012, India.|Indian Council of Agricultural Research (ICAR) - National Research Centre on Plant Biotechnology, Indian Agricultural Research Institute Campus, New Delhi 110012, India.
Jawahar Lal
JL
Katara
Indian Council of Agricultural Research (ICAR) - National Research Centre on Plant Biotechnology, Indian Agricultural Research Institute Campus, New Delhi 110012, India.|Indian Council of Agricultural Research (ICAR) - National Research Centre on Plant Biotechnology, Indian Agricultural Research Institute Campus, New Delhi 110012, India.
Sarvjeet
S
Kaur
Indian Council of Agricultural Research (ICAR) - National Research Centre on Plant Biotechnology, Indian Agricultural Research Institute Campus, New Delhi 110012, India.|Indian Council of Agricultural Research (ICAR) - National Research Centre on Plant Biotechnology, Indian Agricultural Research Institute Campus, New Delhi 110012, India.
Gouthami Krishna
GK
Kumari
Indian Council of Agricultural Research (ICAR) - National Research Centre on Plant Biotechnology, Indian Agricultural Research Institute Campus, New Delhi 110012, India.|Indian Council of Agricultural Research (ICAR) - National Research Centre on Plant Biotechnology, Indian Agricultural Research Institute Campus, New Delhi 110012, India.
Nagendra Kumar
NK
Singh
D000818:Animals; D001413:Bacillus thuringiensis / Q000235:genetics* / Q000302:isolation & purification; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000235:genetics* / Q000494:pharmacology; D018556:Crops, Agricultural; D017753:Ecosystem; D004731:Endotoxins / Q000235:genetics* / Q000494:pharmacology; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D003368:Gossypium / Q000469:parasitology*; D006460:Hemolysin Proteins / Q000235:genetics* / Q000494:pharmacology; D007194:India; D007306:Insecticides / Q000494:pharmacology*; D009036:Moths / Q000382:microbiology*
D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D004731:Endotoxins; D006460:Hemolysin Proteins; D007306:Insecticides; C030956:insecticidal crystal protein, Bacillus Thuringiensis
Bacillus thuringiensis; Helicoverpa armigera; cry2 genes; cry2Af2; gènes cry2; gènes insecticides; insecticidal genes