Multilocus sequence typing and antimicrobial resistance in Enterococcus faecium isolates from fresh produce

Area of Science:

• Microbiology
• Food Safety
• Antimicrobial Resistance

Background:

• Enterococcus faecium is a common bacterium found in various environments, including fresh produce.
• Understanding the genetic relatedness and antimicrobial resistance of foodborne E. faecium is crucial for public health and food safety.

Purpose of the Study:

• To investigate the genetic relationship between Enterococcus faecium isolates from fresh produce and strains from other sources.
• To determine the antimicrobial resistance profiles of these fresh produce E. faecium isolates.

Main Methods:

• Multi-locus sequence typing (MLST) was employed to analyze 22 E. faecium isolates from fresh produce.
• Antimicrobial susceptibility testing was performed for various antibiotics and biocides.

Main Results:

• MLST revealed 7 distinct sequence types (STs), with ST 296 and ST 94 being the most prevalent.
• Isolates were sensitive to vancomycin and imipenem but resistant to cefotaxime and ceftazidine.
• Effective inhibition was observed with quaternary compounds, biguanides, polyguanides, and bisphenols, with hexadecylpyridinium chloride being the most potent.

Conclusions:

• The Enterococcus faecium isolates from fresh produce are genetically distinct from clinically relevant strains, particularly CC17.
• The observed antimicrobial resistance patterns highlight differences between foodborne and clinical E. faecium populations.
• Findings contribute to understanding the ecology and potential risks associated with E. faecium in the food chain.