Phenotypic and genotypic features of new autoagglutinating Bacillus thuringiensis strains

• Published in: Journal of invertebrate pathology Vol. 98; no. 1; pp. 85 - 92
• Main Authors: Chaves, J.Q., Cavados, C.F.G., Rabinovitch, L.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01-05-2008; Elsevier
• Subjects: Aedes - microbiology; Aedes aegypti; agglutination; Animals; Autoagglutinating strains; Bacillus thuringiensis; Bacillus thuringiensis - classification; Bacillus thuringiensis - genetics; Bacillus thuringiensis - isolation & purification; bacterial insecticides; Biological and medical sciences; Biological control; Control; crystal proteins; Culex - microbiology; Culex quinquefasciatus; DNA, Bacterial - genetics; electrophoresis; Fundamental and applied biological sciences. Psychology; genetic polymorphism; Genotype; Larva - microbiology; MLEE; Mosquitocidal strains; Phenotype; Phytopathology. Animal pests. Plant and forest protection; Polymorphism, Genetic - genetics; Protozoa. Invertebrates; random amplified polymorphic DNA technique; RAPD-PCR; SDS–PAGE; serotypes; strain differences; toxicity; Bacillus thuringiensis; RAPD-PCR; Aedes aegypti; Mosquitocidal strains; MLEE; SDS–PAGE; Autoagglutinating strains; Culex quinquefasciatus; Entomopathogen; Insecta; Biological control; Bacillaceae; Pest; Microbiological control; Bacillales; RAPD- PCR; Bacteria; Biopesticide; Genotype; Random amplified polymorphic DNA marker; Polymerase chain reaction; Toxin; SDS-PAGE; Phenotype; Arthropoda; Culicidae; Invertebrata; Diptera; Microbial insecticide
• ISSN: 0022-2011; 1096-0805
• DOI: 10.1016/j.jip.2008.01.002

A total of 28 autoagglutinating strains of
Bacillus thuringiensis were isolated from different ecologic niches and distinct sites. Twenty-six strains demonstrated toxicity to mosquito larvae of
Aedes aegypti and
Culex quinquefasciatus. The electrophoretic protein profiles of the crystal components were studied. Twenty-three out of the 28 strains showed the same larvicidal activity and the same protein profiles as
B. thuringiensis serovar
israelensis. Using isoenzyme analysis (MLEE), it was observed the presence of three electrophoretic types (ETs). The mosquitocidal strains grouped into one ET. The random amplified polymorphic DNA analysis (RAPD) was evaluated using six primers, which demonstrated three different patterns for the 28 autoagglutinating strains, allowing correlation of the profiles obtained with the toxicity observed in the bioassays. The RAPD patterns for mosquitocidal strains were identical to the one of serovar
israelensis. However, to strains of low toxicity, each primer generated distinctive RAPD patterns, which demonstrated that these strains belong to different serovars. Although the antigenic classification the 26 autoagglutinating strains of
B. thuringiensis could not be determined by classical flagellar serotyping, MLEE and RAPD profiles proved these strains to be compatible with
B. thuringiensis serovar
israelensis.