IBR   13079
INSTITUTO DE BIOLOGIA MOLECULAR Y CELULAR DE ROSARIO
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Functional characterization of a novel Acinetobacter baumannii insertion sequence, ISAba825
Autor/es:
RAVASI P.; LIMANSKY A.; VIALE A.; MUSSI M.A.
Lugar:
Tucumán. Argentina
Reunión:
Congreso; XLV Reunión Anual de la Sociedad Argentina de Investigación Bioquímica y Biología Molecular (SAIB); 2009
Institución organizadora:
Sociedad Argentina de Investigación Bioquímica y Biología Molecular (SAIB)
Resumen:
We previously showed that A. baumannii CarO functions as an outer membrane channel for basic amino acids and carbapenem b-lactam antibiotics, and that its loss is correlated with carbapenem resistance. The natural inactivation of carO by insertion elements such as ISAba825, was identified as responsible for CarO loss indicating that the element is involved in A. baumannii genome plasticity. We evaluated here by PCR the distribution of ISAba825 among the genus Acinetobacter and other clinical bacterial species sharing habitats with A. baumannii. Among different strains analyzed, including members of the Acinetobacter genus as well as enterobacterial clinical strains and P. aeruginosa, we detected ISAba825 only in Acinetobacter lwoffii. For further studies, we tagged ISAba825 with a kanamycin resistance gene cassette and cloned this construction into a conditionally suicide plasmid (AmpR) for A. baumannii and E. coli. The selection of kanamycin-resistant, ampicillin-sensitive colonies of these bacteria after transformation and plating was used as a criterion for identifying transposition events. We could demonstrate by this approach transposition of ISAba825::Kn in A. baumannii but not in E. coli.   The overall results indicated that ISAba825 could transpose only in some members of the genus Acinetobacter and that either A. baumannii or A. lwoffii could act as reservoir of the element.