Yersinia intermedia: A new species of enterobacteriaceae composed of rhamnose-positive, melibiose-positive, raffinose-positive strains (formerly called Yersinia enterocolitica or Yersinia enterocolitica-like)

Yersinia intermedia sp. nov. is defined biochemically and genetically. Y. intermedia strains belong to a single DNA relatedness group that is separable from Y. enterocolitica, Y. frederiksenii, Y. kristensenii, and Y. pseudotuberculosis. Y. intermedia is positive in reactions for melibiose, raffinose, α-methyl-d-glucoside, rhamnose, and usually Simmons' citrate. It is metabolically more active at 22-28°C than at 35-37°C. These positive reactions serve to distinguish Y. intermedia from Y. enterocolitica and Y. kristensenii. Positive melibiose, raffinose, and α-methyl-d-glucoside reactions differentiate Y. intermedia from the other new rhamnose-positive species, Y. frederiksenii. Y. intermedia is separated from Y. pseudotuberculosis by its positive reactions for sucrose, indole, cellobiose, i-inositol, d-sorbitol, α-methyl-d-glucoside, and ornithine decarboxylase. Yersinia biotype X2, an additional rhamnose-positive, sucrose-negative group, as yet not identified to a species, and X1, a sucrose- and ornithine decarboxylase-negative Yersinia biotype, do not belong to Y. intermedia. Strain 3953 (=CIP 80-28=ATCC 29909=Bottone 48=Chester 48) is proposed as the type strain for Y. intermedia.