title: The clonal structure of Bacillus thuringiensis isolates from north-east Poland does not correlate with their cry gene diversity.
abstract: The genetic relationship among 103 natural Bacillus thuringiensis isolates was investigated on the basis of polymerase chain reaction amplification of their specific crystal (cry) protein type genes and chromosomal DNA profiling by pulsed-field gel electrophoresis (PFGE). The strains were recovered from the intestines of small wild rodents and insectivores from the Biebrza National Park and the Lomza Landscape Park of the Narew River Valley in north-east Poland. The percentage of B. thuringiensis strains harbouring genes coding for toxins active against Lepidoptera (cry1, cry2, cry9) was very high (64%) compared with that of Diptera-specific strains (cry4, 14%). No strain with cry genes coding for proteins directed against coleopteran larvae and nematodes was found. After digestion with NotI and AscI, only nine PFGE pulsotypes were observed among all isolates, indicating a clonal structure for the B. thuringiensis population from NE Poland. Interestingly, no correlation was observed between the DNA pulsotype strains and their crystal gene content and diversity. These results therefore emphasize the importance of cry gene horizontal transfer occurring among natural isolates of B. thuringiensis.
authors.affiliation: Department of Microbiology, Institute of Biology, University of Białystok, 15-950 Białystok, Swierkowa 20B, Poland. izabelas@uwb.edu
authors.forename: Izabela
authors.initials: I
authors.lastname: Swiecicka
authors.forename: Jacques
authors.initials: J
authors.lastname: Mahillon
mesh_terms: D000818:Animals; D000835:Animals, Wild / Q000382:microbiology; D001413:Bacillus thuringiensis / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000145:classification / Q000235:genetics* / Q000494:pharmacology; D001427:Bacterial Toxins / Q000145:classification / Q000235:genetics* / Q000494:pharmacology; D016172:DNA Fingerprinting / Q000379:methods; D004269:DNA, Bacterial / Q000032:analysis; D004175:Diptera / Q000187:drug effects; D016521:Electrophoresis, Gel, Pulsed-Field; D004731:Endotoxins / Q000145:classification / Q000235:genetics* / Q000494:pharmacology; D014644:Genetic Variation; D016680:Genome, Bacterial; D005838:Genotype; D006460:Hemolysin Proteins; D007422:Intestines / Q000382:microbiology; D007915:Lepidoptera / Q000187:drug effects; D011044:Poland; D016133:Polymerase Chain Reaction; D012377:Rodentia / Q000382:microbiology
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004269:DNA, Bacterial; D004731:Endotoxins; D006460:Hemolysin Proteins; C030956:insecticidal crystal protein, Bacillus Thuringiensis