Properties of corynephage attachment site and molecular epidemiology of Corynebacterium ulcerans isolated from humans and animals in Japan.

Sporadic reports of Corynebacterium ulcerans infection in humans and animals have become increasingly common throughout the world. Between 2001 and 2006, five human cases, in addition to isolation of the bacterium from the carcasses of Orcinus orca and Panthera leo, were reported in Japan. While an isolate from P. leo generated only phospholipase D (PLD), the other isolates produced both PLD and diphtheria-like toxin (DLT). Pulsed-field gel electrophoresis analysis showed that isolates from P. leo and humans were genetically homologous. Southern blotting found that a human isolate was lysogenized by two corynephages coding DLT. Sequence analysis of the region of the DLT gene revealed that the integration in C. ulcerans occurred in the same manner as that in C. diphtheriae.