IMPAM   23988
INSTITUTO DE INVESTIGACIONES EN MICROBIOLOGIA Y PARASITOLOGIA MEDICA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Achromobacter xylosoxidans: An Emerging Pathogen Carrying Different Elements Involved In Horizontal Genetic
Autor/es:
TRAGLIA G.; ADAMS C.; ALMUZARA M.N.; MERKIER A.K.; VAY C.A; CENTRON D.; RAMIREZ M.S.
Lugar:
Washington
Reunión:
Congreso; 10th Annual ASM Biodefense and Emerging Diseases Research Meeting; 2012
Institución organizadora:
ASM American Society for Microbiology
Resumen:
In the last few years numerous cases of multidrug resistant Achromobacter Xylosoxidans infections have been documented in immunocompromised and cystic fibrosis patients. To gain insights into the molecular mechanisms and mobile elements contributing to multidrug resistance of this bacterium, we studied 28 non-epidemiological A. xylosoxidans clinical isolates from Argentina. All isolates were identified using standard biochemical tests, API 20NE (Biomeriux), and 16S rRNA gene sequencing. Clonal relationships were determined by macrorestriction mapping. Total DNA was used as template for PCR amplification reactions. Specific primers for plasmids (IncP, IncW, IncA/C, IncN, IncFII, repAci1), transposons (Tn1331, Tn3, Tn7), insertion sequences (IS) (IS26, IS1999, IS440, ISPa12, ISPa13, IS18, IS125, IS1008, ISAba1), and the blaampC, intI1 and intI2 genes were used in PCR reactions. The variable regions (vr) of integrons and their association with IS26 and IS440 were analyzed by PCR cartography. IS26 and IS440 were found in 2 and 7 isolates, respectively. Wide host range IncP plasmids were identified in 10 isolates. The intI1 and intI2 genes were present in 10 and 3 isolates, respectively. PCR cartography showed 4 different arrays in the vr of class 1 integrons. Relevant gene cassettes found in these vr include the aminoglycoside resistance aac(6’)-Ib and aadA1, the trimethoprim resistance dfrA1 and dfrA16, and the beta-lactamase blaOXA-2. In only one of the class 2 integrons a vr was amplified, which included dfrA1. No association of integrons with IS26 and IS440 were found. The blaampC gene was found in all isolates, confirming its ubiquitous nature. Our results show that A. xylosoxidans clinical isolates contain a rich variety of genetic elements commonly associated with resistance genes and their dissemination. This supports the hypothesis that A. xylosoxidans is becoming a reservoir of resistance determinants included in mobile elements.