Mechanisms of Linezolid Resistance Among Enterococci of Clinical Origin in Spain—Detection of optrA- and cfr(D)-Carrying E. faecalis

Microorganisms

AndreaT. Feßler¹  Dennis Hanke¹  Stefan Schwarz¹  Inga Eichhorn¹  Carmen Aspiroz²  Luis Torres³  CarlaAndrea Alonso⁴  JoséManuel Azcona-Gutiérrez⁴  Cristina Seral⁵  Juan-Ignacio Alós⁶  MarOlga Pérez-Moreno⁷  Carmen Torres⁸  Laura Ruiz-Ripa⁸ 

[1] Institute of Microbiology and Epizootics, Department of Veterinary Medicine, Freie Universität Berlin, 14163 Berlin, Germany;Servicio Microbiología, Hospital Royo-Villanova, 50015 Zaragoza, Spain;Servicio Microbiología, Hospital San Jorge, 22004 Huesca, Spain;Servicio Microbiología, Hospital San Pedro, 26006 Logroño, Spain;Servicio Microbiología, Hospital Universitario Lozano Blesa, 50009 Zaragoza, Spain;Servicio Microbiología, Hospital Universitario de Getafe, 28905 Getafe, Spain;Servicio Microbiología, Hospital Verge de la Cinta, 43500 Tortosa, Spain;Área de Bioquímica y Biología Molecular, Universidad de La Rioja, 26006 Logroño, Spain;

关键词: whole genome sequencing;    optrA;    cfr(D);    linezolid;    Enterococcus spp.;   

DOI  :  10.3390/microorganisms8081155

来源: DOAJ

【 摘 要 】

The mechanisms of linezolid resistance among 13 E. faecalis and 6 E. faecium isolates, recovered from six Spanish hospitals during 2017–2018, were investigated. The presence of acquired linezolid resistance genes and mutations in 23S rDNA and in genes encoding for ribosomal proteins was analyzed by PCR and amplicon sequencing. Moreover, the susceptibility to 18 antimicrobial agents was investigated, and the respective molecular background was elucidated by PCR-amplicon sequencing and whole genome sequencing. The transferability of the linezolid resistance genes was evaluated by filter-mating experiments. The optrA gene was detected in all 13 E. faecalis isolates; and one optrA-positive isolate also carried the recently described cfr(D) gene. Moreover, one E. faecalis isolate displayed the nucleotide mutation G2576T in the 23S rDNA. This mutation was also present in all six E. faecium isolates. All linezolid-resistant enterococci showed a multiresistance phenotype and harbored several antimicrobial resistance genes, as well as many virulence determinants. The fexA gene was located upstream of the optrA gene in 12 of the E. faecalis isolates. Moreover, an erm(A)-like gene was located downstream of optrA in two isolates recovered from the same hospital. The optrA gene was transferable in all but one E. faecalis isolates, in all cases along with the fexA gene. The cfr(D) gene was not transferable. The presence of optrA and mutations in the 23S rDNA are the main mechanisms of linezolid resistance among E. faecalis and E. faecium, respectively. We report the first description of the cfr(D) gene in E. faecalis. The presence of the optrA and cfr(D) genes in Spanish hospitals is a public health concern.

【 授权许可】

Unknown