Antimicrobial Resistance and Antimicrobial Activity of Obtained from Two Spanish Hospitals.

is a coagulase-negative-staphylococci (CoNS) that lately has gained special attention in public health as a human pathogen and also as a bacteriocin-producer bacteria. In this study, we characterized 56 isolates recovered from human samples in two Spanish hospitals. Antimicrobial susceptibility testing was performed and antimicrobial resistance and virulence genotypes were determined. Antimicrobial activity (AA) production was evaluated by the method against 37 indicator bacteria, including multidrug-resistant (MDR) isolates, and the presence of the D gene coding for lugdunin bacteriocin was analyzed by PCR. The antibiotic resistance detected was as follows (% resistance/genes detected): penicillin (44.6%/Z), oxacillin (1.8%/ on SCC-V), erythromycin-clindamycin inducible (7.1%/(C), ), tetracycline (5.3%/), gentamicin and/or tobramycin (3.6%/(4')-Ia, (6')-(2″)), and fosfomycin (21.4%). A MDR phenotype was detected in 5% of isolates. Twenty-one of the isolates showed susceptibility to all 20 antibiotics tested (37.5%). The screening for AA revealed 23 antimicrobial producer (AP) isolates with relevant inhibition against coagulase-positive-staphylococci (CoPS), including both methicillin-susceptible and -resistant . The D gene was detected in 84% of the 56 isolates. All of the AP isolates ( = 23) carried the D gene and it was also detected in 24 of the non-AP isolates, suggesting different gene expression levels. One of the AP isolates stood out due to its high antimicrobial activity against more than 70% of the indicator bacteria tested, so it will be further characterized at genomic and proteomic level.