Antibiotic resistance and restriction endonucleases in fecal enterococci of chamois (Rupicapra rupicapra Linnaeus, 1758).

Two hundred eighty-four isolates of enterococci from feces of wild living chamois from alpine environments were tested for sensitivity to three antibiotics. Low frequency of resistance was observed in studied enterococcal populations (about 5 % for tetracycline and erythromycin and 0 % for ampicillin). In six animals, the population of enterococci lacked any detectable resistance. Our data indicated that enterococcal population in feces of the majority of studied animals did not encounter mobile genetic elements encoding antibiotic resistance probably due to spatial separation and/or due to low exposure to the antibiotics. Based on resistance profiles observed, three populations were analyzed for the presence of restriction endonucleases. The restriction enzymes from two isolates-31K and 1K-were further purified and characterized. Restriction endonuclease Efa1KI recognizes CCWGG sequence and is an isoschizomer of BstNI. Endonuclease Efc31KI, a BsmAI isoschizomer, recognizes the sequence GTCTC and it is a first restriction endonuclease identified in Enterococcus faecium. Our data indicate that restriction-modification (R-M) systems do not represent an efficient barrier for antibiotic resistance spreading; enterococcal populations colonized by antibiotics resistance genes were also colonized by the R-M systems.