[Insertion mutations in Pseudomonas pseudomallei genome induced by transposons Tn10. Tn9, and Tn5].

Tn10 and Tn9 from temperature-sensitive replicons RPI::Tn10 Rep is and RP1::Tn9 Rep ts and Tn5 from the "suicidal" vector pSUP5011 may integrate in the P. pseudomallei chromosome. Transposons induced auxotrophic mutations of different spectrum, depending on the strain, Tn element, and defects in the genes responsible for the mobility sign, function of some extracellular elements (lecithinase and lipase), hemolytic activity, and antigen 8 synthesis, which are considered as the potential factors of the pathogenicity of melioidosis agent. No secondary restructuring induced by Tn elements were detected in the domains adjacent to insertion sites. Plasmids RP1::Tn10 Rep ts and RP1::Tn9 Rep ts were stable in insertion mutant cells, mediating the variable TR-TS phenotype probably indicating that plasmid integration with the chromosome is unstable.