REPI researchers, lead by Hospital Son Espases Group, have used whole genome sequencing (WGS) for the characterization of the frequently extensively-drug resistant (XDR), P. aeruginosa high-risk clone ST175, widely disseminated in Spanish hospitals and at international level. The resistome of ST175 was mainly determined by mutational events, with resistance traits common to all or nearly all of the 22 strains sequenced, including specific ampR mutations leading to ampC overexpression, specific mutations in oprD conferring carbapenem resistance or a mexZ mutation leading to MexXY overexpression. All isolates additionally harbored an aadB gene conferring gentamicin and tobramycin resistance. Several other resistance traits were specific to certain geographic areas such as a streptomycin resistance aadA13 gene or a glpT mutation conferring fosfomycin resistance. Finally, several unique resistance mutations were detected in single isolates; particularly interesting among them were those in genes encoding PBPs (PBP1A, PBP3 and PBP4). Thus, these results provide valuable information for understanding the genetic basis of resistance and the dynamics of dissemination and evolution of high-risk clones.
Gabriel Cabot, Carla López-Causapé, Alain A. Ocampo-Sosa, Lea M. Sommer, María Ángeles Domínguez, Laura Zamorano, Carlos Juan, Fe Tubau, Cristina Rodríguez, Bartolomé Moyà, Carmen Peña, Luis Martínez-Martínez, Patrick Plesiat, Antonio Oliver, and Spanish Network for Research in Infectious Diseases (REIPI)
Deciphering the resistome of the widespread P. aeruginosa ST175 international high-risk clone through whole genome sequencingAntimicrob. Agents Chemother. Accepted manuscript posted online 10 October 2016 ,doi:10.1128/AAC.01720-16