Characterization of Yersinia enterocolitica and Yersinia pseudotuberculosis by Deoxyribonucleic Acid Hybridization and by Biochemical Reactions

Abstract
Strains of Y. enterocolitica and Y. pseudotuberculosis were characterized by DNA hybridization, and the extent of DNA relatedness between the strains was assessed by hydroxyapatite chromatography. DNAs from 24 strains of Y. pseudotuberculosis were highly related, but Y. pseudotuberculosis was only 40-60% related to Y. enterocolitica. Y. enterocolitica strains formed 3 DNA relatedness groups, and the data strongly suggest a 4th relatedness group. Each relatedness group can be defined biochemically. One DNA relatedness group corresponds to typical Y. enterocolitica; the 2nd is rhamnose positive; the 3rd is rhamnose positive, melibiose positive, .alpha.-methyl glucoside positive and raffinose positive. The suggested 4th hybridization group is sucrose negative. Although all of these DNA relatedness groups should remain in the genus Yersinia, only the 1st group is Y. enterocolitica. All of the yersiniae tested are distantly, but significantly, related to other members of Enterobacteriaceae. Yersiniae were more related to members of Enterobacteriaceae than to Pasteurella multocida.