Ewingella americana gen.nov., sp.nov., a new Enterobacteriaceae isolated from clinical specimens.

We propose the name Ewingella gen.nov. for a new group in the Enterobacteriaceae. Ewingella is phenotypically distinct from all other groups of Enterobacteriaceae. The members of this genus are lipase- and deoxyribonuclease-negative; Voges-Proskauer-positive; lysine-, ornithine- and arginine-decarboxylase-negative; anaerogenic; they produce acid from glucose in the presence (and absence) of iodoacetate, but fail to produce acid from L-arabinose, melibiose, raffinose, D-sorbitol or sucrose. DNA-relatedness studies (S1-nuclease method) showed that the 10 Ewingella strains studied form a single DNA-hybridization group which is less than 21% related to other members of the Enterobacteriaceae. This single DNA-hybridization group is named Ewingella americana sp. nov. The type strain of E. americana is CDC 1468-78 (= ATCC 33852 = CIP 8194). Although the 10 strains of E. americana were isolated from clinical sources in the United States, the clinical significance of these organisms is not known.