title: Genetic diversity of Bacillus cereus/B. thuringiensis isolates from natural sources.
abstract: The genetic diversity and relationships among 154 Bacillus cereus/B. thuringiensis isolates recovered from soil samples from five geographic areas in Norway were investigated with multilocus enzyme electrophoresis (MEE). Cluster analysis revealed two major groups (designated cluster I and cluster II) separated at genetic distance greater than 0.55. Cluster I included 62 electrophoretic types (ETs) originating from all five locations, whereas, in cluster II, all but one isolate were from the same location. The isolates were also serotyped with B. thuringiensis flagellar antisera, and 28 distinct serotypes were identified. In general, serotyping did not show correlation to the genetic diversity of the isolates. The presence of IS231- and IS240-like transposable elements was detected in 14% of the strains of cluster II only. Parasporal crystals were observed in three strains; ten other strains were toxic to Trichoplusia ni. We conclude that B. cereus/B. thuringiensis from soil exhibit a high degree of recombination.
authors.affiliation: Biotechnology Centre of Oslo and Institute of Pharmacy, University of Oslo, PB1125, 0316 Oslo 3, Norway.
authors.forename: E
authors.initials: E
authors.lastname: Helgason
authors.forename: D A
authors.initials: DA
authors.lastname: Caugant
authors.forename: M M
authors.initials: MM
authors.lastname: Lecadet
authors.forename: Y
authors.initials: Y
authors.lastname: Chen
authors.forename: J
authors.initials: J
authors.lastname: Mahillon
authors.forename: A
authors.initials: A
authors.lastname: Lövgren
authors.forename: I
authors.initials: I
authors.lastname: Hegna
authors.forename: K
authors.initials: K
authors.lastname: Kvaløy
authors.forename: A B
authors.initials: AB
authors.lastname: Kolstø
mesh_terms: D001409:Bacillus cereus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D001413:Bacillus thuringiensis / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000378:metabolism; D001427:Bacterial Toxins; D004251:DNA Transposable Elements / Q000235:genetics; D004731:Endotoxins / Q000378:metabolism; D014644:Genetic Variation; D006460:Hemolysin Proteins; D009664:Norway; D010572:Pest Control, Biological; D010802:Phylogeny; D012703:Serotyping; D012988:Soil Microbiology
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004251:DNA Transposable Elements; D004731:Endotoxins; D006460:Hemolysin Proteins; C030956:insecticidal crystal protein, Bacillus Thuringiensis