title: Cloning, characterization and diversity of insecticidal crystal protein genes of bacillus thuringiensis native isolates from soils of Andaman and Nicobar Islands.
abstract: Bt strains were isolated from soils of Andaman and Nicobar Islands and characterized by microscopic and molecular methods. Diversity was observed both in protein and cry gene profiles, where majority of the isolates showed presence of 65 kDa protein band on SDS-PAGE while rest of them showed 130, 72, 44, and 29 kDa bands. PCR analysis revealed predominance of cry1I and cry7, 8 genes in these isolates. The PCR screening strategy presented here led us to identify putative novel cry genes which could be active against Coleoptera insects. Variation in the nucleotide sequences of cry genes from the isolates suggests that the genetic diversity of Bt isolates results from the influence of different ecological factors and spatial separation between strains generated by the conquest of different habitats in the soils of Andaman and Nicobar islands. The implications of our studies are important from the point of view of identifying novel cry genes that could be toxic to insects other than lepidoptera.
authors.affiliation: Bio Pesticide Laboratory, Division of Biotechnology, Indian Institute of Horticultural Research, Hessarghatta Lake Post, Bangalore, 560089 Karnataka, India.
authors.forename: H M
authors.initials: HM
authors.lastname: Mahadeva Swamy
authors.forename: R
authors.initials: R
authors.lastname: Asokan
authors.forename: S N
authors.initials: SN
authors.lastname: Nagesha
authors.forename: D K
authors.initials: DK
authors.lastname: Arora
authors.forename: Ajantha
authors.initials: A
authors.lastname: Birah
authors.forename: Riaz
authors.initials: R
authors.lastname: Mahmood
mesh_terms: D000818:Animals; D001413:Bacillus thuringiensis / Q000235:genetics* / Q000302:isolation & purification* / Q000378:metabolism; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D003001:Cloning, Molecular; D001517:Coleoptera / Q000187:drug effects; D004731:Endotoxins / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D014644:Genetic Variation; D006460:Hemolysin Proteins / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D007194:India; D007306:Insecticides / Q000378:metabolism / Q000494:pharmacology; D008969:Molecular Sequence Data; D012987:Soil; D012988:Soil Microbiology
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D004731:Endotoxins; D006460:Hemolysin Proteins; D007306:Insecticides; D012987:Soil; C030956:insecticidal crystal protein, Bacillus Thuringiensis