Author(s):
Sabença, Carolina ; de Sousa, Telma ; Oliveira, Soraia ; Viala, Didier ; Théron, Laetitia ; Chambon, Christophe ; Hébraud, Michel ; Beyrouthy, Racha ; Bonnet, Richard ; Caniça, Manuela ; Poeta, Patrícia ; Igrejas, Gilberto
Date: 2020
Persistent ID: http://hdl.handle.net/10362/120027
Origin: Repositório Institucional da UNL
Subject(s): Antibiotic resistance; Enterococcus spp; MALDI-TOF MS; Next-generation sequencing; Processed meat; Biochemistry, Genetics and Molecular Biology(all); Immunology and Microbiology(all); Agricultural and Biological Sciences(all)
Description
Ação n.º: TC-14 / 2017 UID/QUI/50006/2020 UIDB/00211/2020 UMR1071 USC-2018
Vancomycin-resistant enterococci (VRE), due to their intrinsic resistance to various commonly used antibiotics and their malleable genome, make the treatment of infections caused by these bacteria less effective. The aims of this work were to characterize isolates of Enterococcus spp. that originated from processed meat, through phenotypic and genotypic techniques, as well as to detect putative antibiotic resistance biomarkers. The 19 VRE identified had high resistance to teicoplanin (89%), tetracycline (94%), and erythromycin (84%) and a low resistance to kanamycin (11%), gentamicin (11%), and streptomycin (5%). Based on a Next-Generation Sequencing NGS technique, most isolates were vanA-positive. The most prevalent resistance genes detected were erm(B) and aac(6')-Ii, conferring resistance to the classes of macrolides and aminoglycosides, respectively. MALDI-TOF mass spectrometry (MS) analysis detected an exclusive peak of the Enterococcus genus at m/z (mass-to-charge-ratio) 4428 ± 3, and a peak at m/z 6048 ± 1 allowed us to distinguish Enterococcus faecium from the other species. Several statistically significant protein masses associated with resistance were detected, such as peaks at m/z 6358.27 and m/z 13237.3 in ciprofloxacin resistance isolates. These results reinforce the relevance of the combined and complementary NGS and MALDI-TOF MS techniques for bacterial characterization.
