ABSTRACT
This chapter presents an approach to the laboratory identification of Y. enterocolitica which utilizes a general schema based on the four deoxyribonucleic acid (DNA)-DNA homology groups of Brenner et al. The laboratory identification of the Gram-negative bacterium, Yersinia enterocolitica, proceeds through two distinct but interwoven avenues — namely recognition of suspect colonies and awareness of several biochemical characteristics, some temperature-dependent, necessary for ascription of an isolate to the genus Yersinia. The biochemical characterization of typical Y. enterocolitica should proceed without great difficulty. The biochemical identification of a suspect Y. enterocolitica as alluded to should be carried out at both 25 and 37° C, as many of the indicated results are manifested only at the lower incubation temperature. Rhamnose-fermenting Y. enterocolitica-like. isolates, until recently, presented a particular diagnostic problem for microbiologists, working in the hospital setting. Sucrose-negative isolates of Y. enterocolitica have only infrequently been recovered from human sources although reports of their occurrence in animals have appeared.
