Insertion sequence elements in Bacillus thuringiensis subsp. darmstadiensis.
Two variants of insertion sequence IS231, named IS231G and H, were isolated from Bacillus thuringiensis subsp. darmstadiensis 73-E-10-2 (BTD2), an isolate toxic to dipteran insects, and characterized by DNA sequence analysis. They are encoded consecutively as direct repeats on an EcoRI fragment of 5.6 kilo base pairs. Direct tandem repeats of IS231 elements have not been previously reported. Both elements are closely related to other members of the IS231 family that have been isolated from B. thuringiensis strains toxic to lepidopteran as well as to dipteran insects. A close correlation exists between the evolutionary relationships of the IS231 sequences determined to data and the toxicity spectrum of the host cell. Probing of BTD2 DNA with a radiolabeled IS231G fragment demonstrated that IS231 elements are located on 55- and 34-MDa plasmids as well as on chromosomal DNA. Chromosomal DNA, but not plasmids, from BTD2 also hybridizes to another, unrelated insertion sequence, IS240, from B. thuringiensis subsp. israelensis, an isolate toxic to dipteran insects. BTD2, therefore, contains IS elements once thought to reside exclusively in either dipteran- or lepidopteran-specific subspecies of B. thuringiensis.
Department of Molecular Biology, University of Wyoming, Laramie 82071.
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D001413:Bacillus thuringiensis / Q000145:classification / Q000235:genetics*; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000235:genetics; D001427:Bacterial Toxins / Q000235:genetics; D001483:Base Sequence; D015342:DNA Probes; D004251:DNA Transposable Elements / Q000235:genetics*; D004269:DNA, Bacterial / Q000145:classification / Q000235:genetics*; D004731:Endotoxins / Q000235:genetics; D006460:Hemolysin Proteins; D007300:Insect Control; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D010957:Plasmids / Q000235:genetics; D011498:Protein Precursors / Q000235:genetics; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics; D017422:Sequence Analysis, DNA
D000083722:Bacillus thuringiensis Toxins; C029103:Bacillus thuringiensis protoxin; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D015342:DNA Probes; D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D004731:Endotoxins; D006460:Hemolysin Proteins; D011498:Protein Precursors; C030956:insecticidal crystal protein, Bacillus Thuringiensis