title: Transfer of Bacillus thuringiensis plasmids coding for delta-endotoxin among strains of B. thuringiensis and B. cereus.
abstract: The recently discovered high-frequency transfer of plasmids between strains of Bacillus thuringiensis was used to study the genetic relationship between plasmids and production of the insecticidal delta-endotoxin crystal. Three strains of B. thuringiensis transmitted the Cry+ (crystal-producing) phenotype to Cry- (acrystalliferous) B. thuringiensis recipients. Agarose gel electrophoresis showed that one specific plasmid from each donor strain was always present in Cry+ "transcipients." The size of the transmissible crystal-coding plasmid varied with the donor strain, being 75 MDal (megadaltons) in size in HD-2, 50 MDal in HD-73, and 44 MDal in HD-263. Immunological analysis showed the Cry+ transcipients to be hybrid strains, having flagella of the recipient serotype and crystals of the donor serotype. These results demonstrate that the structural genes for the delta-endotoxin are plasmid borne. Crystal-coding plasmids also transferred into two strains of the related species Bacillus cereus and yielded transcipients that produced crystals of the same antigenicity as the donor strain.
mesh_terms: D001409:Bacillus cereus / Q000235:genetics*; D001413:Bacillus thuringiensis / Q000235:genetics*; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D001483:Base Sequence; D003001:Cloning, Molecular; D004731:Endotoxins / Q000235:genetics* / Q000302:isolation & purification; D006460:Hemolysin Proteins; D008970:Molecular Weight; D009154:Mutation; D010957:Plasmids; D013045:Species Specificity
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004731:Endotoxins; D006460:Hemolysin Proteins; C030956:insecticidal crystal protein, Bacillus Thuringiensis