title: Genotypic and technological characterization of enterococci isolated from artisanal Fiore Sardo cheese.
abstract: A total of 118 enterococcal strains isolated from artisanal Fiore Sardo cheese were characterized technologically and genetically. The presence of potential virulence factors was also investigated. Strains were classified as Ec. faecium (84 strains), Ec. durans (24 strains) and Ec. faecalis (10 strains). RAPD-PCR analysis with two different primers (M13 and XD9) confirmed species identification and proved useful for the detection of interstrain variations, especially among Ec. faecium isolates. Most strains could hydrolyse casein and had weak acidifying activity in milk. None of the isolates produced lipolytic reactions. Gelatinase activity was observed in two strains of Ec. faecalis and one strain of Ec. durans. beta-Haemolysis on horses' blood was never detected in any of the strains, independently of species. Most strains produced tyramine from tyrosine but none decarboxylated lysine, histidine or ornithine. Overall, a wide spectrum of resistance was observed. Almost all strains were resistant to the aminoglycosides, gentamycin, kanamycin, streptomycin, neomycin, and to the semisynthetic penicillin, oxacillin, but resistance to vancomycin was not widespread among our strains: only one Ec. faecium and one Ec. durans strain were found to be vancomycin resistant. Our results show a certain diversity in technological traits of the enterococcal strains isolated from artisanal Fiore Sardo, together with a low incidence of some potentially pathogenic traits of health concern.
authors.affiliation: Department of Experimental Biology, Section of Hygiene, University of Cagliari, Italy. scosenti@unica.it
authors.forename: Sofia
authors.initials: S
authors.lastname: Cosentino
authors.forename: M Barbara
authors.initials: MB
authors.lastname: Pisano
authors.forename: Arianna
authors.initials: A
authors.lastname: Corda
authors.forename: M Elisabetta
authors.initials: ME
authors.lastname: Fadda
authors.forename: Carla
authors.initials: C
authors.lastname: Piras
mesh_terms: D002611:Cheese / Q000032:analysis / Q000382:microbiology*; D004352:Drug Resistance, Microbial; D016983:Enterococcus / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification*; D013293:Enterococcus faecalis / Q000235:genetics / Q000302:isolation & purification; D016984:Enterococcus faecium / Q000235:genetics / Q000302:isolation & purification; D005838:Genotype; D007558:Italy; D019105:Random Amplified Polymorphic DNA Technique; D037521:Virulence Factors / Q000032:analysis
chemical_list: D037521:Virulence Factors