Genotypic and phenotypic characteristics of Yersinia spp. isolates from food and man

Yersinia strains collected by the Unit of Enteric Pathogens of the Istituto Superiore di Sanita were analysed for bioserogroup, virulence-related char acteristics, DNA plasmid profile and biotype. The isolates were from clinic al and food samples, 26 were Y. enterocolitica, four Y. intermedia and four Y. frederiksenii. Seventeen were isolated in Northern Italy 11 in Southern Italy, five in Central Italy and one from a sample of mussels imported fro m Greece. Virulence-related characteristics were expressed only by four Y. enterocolitica, bioserogroup 4:O3 associated with the presence of a plasmid weighing 76.8 Kbp. The DNA digested by Spel and Xbal and analysed by PFGE generated restriction patterns of 12-23 bands, ranging between 400 and 20 K bp. The similarities of the DNA fingerprintings of Y, enterocolitica strain s generated using Spel and Xbal and calculated by Dice's index were not clo sely related to bioserogroup. (C) 2000 Academic Press.