Spiroplasma mirum, a New Species from the Rabbit Tick (Haemaphysalis leporispalustris)

Abstract

Three hundred and eighty-four strains of bacteria representing the genera of the Enterobacteriaceae were examined over a wide range of biochemical, physiological, and morphological characters. The data were subjected to numerical analysis, and the resulting 33 clusters were equated as far as possible with established taxa within the Enterobacteriaceae. The clusters formed three groups. Group A corresponded to the tribe Klebsielleae and consisted of the genera Enterobacter, Klebsiella, and Serratia. The data suggest that Enterobacter and Klebsiella, could be combined into a single genus, whereas Hafnia alvei should be retained in a genus separate from Enterobacter. Group B comprised the tribes Edwardsielleae, Salmonelleae, and Escherichieae. Strains of Edwardsiella species fell into two clusters, suggestive of possible biotype differences or perhaps two separate species. Many of Kauffmann's biochemical subgroup 1 salmonellae could be combined into a single species, which on grounds of priority should be designated Salmonella enteritidis (Gaertner) Castellani and Chalmers. However, there are other subgroup 1 serotypes which clearly do not belong in this species. Further study is suggested. Three species of Shigella, i.e., S. boydii. S. flexneri, and S. dysenteriae, were not separated by the analyses performed in this study. Either the three species cannot be identified on the basis of the biochemical characters employed or their identification requires considerable modification. Also included in group B were members of the genus Yersinia. Group C, representing the tribe Proteae, requires considerable revision, if a classification reflecting both molecular genetic and phenetic taxonomic relationships is to be attained.