Genotypic diversity, antibiotic resistance and bacteriocin production of enterococci isolated from rhizospheres

Abstract

This study aimed to identify and to characterize rhizospheric-derived enterococci. The results showed the prevalence of Enterococcus faecium species (97%) vs. Enterococcus durans (3%). Susceptibility testing for antibiotics showed a low percentage of resistance to erythromycin (3.2%) and tetracycline (11.2%), and intermediate resistance to vancomycin (6.5%). Nevertheless, a high proportion of bacteriocin production was recorded. Furthermore, PCR detection of antibiotic resistance and bacteriocin production-encoding genes was investigated. Pulsed-field gel electrophoresis typing (PFGE) showed a great variability of enterococci in the rhizosphere. Moreover, mutilocus-sequence-typing analysis (MLST) revealed the identification of three new sequence types (STs), which were registered as ST613, ST614 and ST615.