The aggregation-mediated conjugation system of Bacillus thuringiensis subsp. israelensis: host range and kinetics of transfer

Curr Microbiol. 1996 Oct;33(4):228-36. doi: 10.1007/s002849900105.


The aggregation-mediated conjugation system in Bacillus thuringiensis subsp. israelensis encoded on the plasmid pXO16 is characterized by the formation of aggregates when Agr+ and Agr- cells are socialized in exponential growth. Using the aggregation phenotypes, we have identified potential recipients of the aggregation-plasmid pXO16 among Bacillus cereus, Bacillus subtilis, Bacillus megaterium, Bacillus sphaericus, and 24 subspecies of B. thuringiensis. We found 14 Agr- strains, i.e., potential recipients of the aggregation system encoded by plasmid pXO16. Five strains contained a conjugative apparatus of their own and were excluded from further examinations. To monitor the transfer of plasmid pXO16, we constructed a transposon insertion of the plasmid with Tn5401. The study of the plasmid transfer of pXO16::Tn5401 indicated the secretion of bacteriocins from both donor strain and recipient strains. Only one out of the nine strains examined was unable to receive the aggregation-plasmid pXO16 and express the aggregation phenotype and the conjugative abilities. It was found that the transfer of plasmid pXO16 to Bacillus thuringiensis subsp. israelensis Agr- strains was 100%. All recipients had acquired the aggregation-plasmid pXO16 and converted to the Agr+ phenotype.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Bacillus / genetics
  • Bacillus thuringiensis / drug effects
  • Bacillus thuringiensis / genetics*
  • Bacillus thuringiensis / growth & development
  • Bacteriocins / biosynthesis
  • Bacteriocins / metabolism
  • Conjugation, Genetic / genetics*
  • DNA / analysis
  • DNA Transposable Elements
  • Electrophoresis, Agar Gel
  • Mutagenesis, Insertional
  • Plasmids / genetics
  • Tetracycline / pharmacology


  • Anti-Bacterial Agents
  • Bacteriocins
  • DNA Transposable Elements
  • DNA
  • Tetracycline