Yersinia intermedia: temperature-dependent bacteriocin production.

Yersinia enterocolitica and related Yersinia species share many temperature-dependent biological attributes. The present report documents temperature-dependent production of a bacteriocin-like substance only among Yersinia strains which ferment L-rhamnose, raffinose, and melibiose and which have been tentatively designed Y. intermedia. When tested by the "lawn-spotting" technique at 25 and 37 degrees C, 7 of 15 Y. intermedia strains produced a bacteriocin only at 25 degrees C with a uniform spectrum of activity against 2 strains of Y. enterocolitica, 1 rhamnose-positive, raffinose-negative, melibiose-negative strain tentatively designated Y. frederiksenii, 8 Y. intermedia, and 3 sucrose- and acetylmethylcarbinol-negative yersinial isolates tested. Bacteriocin-like activity was not detected among the Y. enterocolitica, Y. frederiksenii, or sucrose-negative yersinial strains tested. The exclusive activity of the Y. intermedia antibacterial substance only against yersiniae and not against other representative Enterobacteriaceae tested supports the placement of these microorganisms within the genus Yersinia and further establishes the singularity of Y. intermedia.