More than 70 characters of 55 strains of Achromobacter xylosoxidans were compared with those of the type strain of A . xylosoxidans, ATCC 27061 (= KM 543). Repeated examination of these 55 strains confirmed the stability of the flagellar morphology and biochemical reaction pattern and xmed that the species can be recognized by these characters. Two strains of Aicaligenes faecalis, two strains of A ZcaZigenes denitrificans, five strains of A lcaligenes sp., and five strains of each of King groups IIIa and IIIb were identified as strains of A . xylosoxidans. The base compositions of the deoxyribonucleic acids of 20 strains are given. The cellular fatty acid composition of extractable and bound lipids of five strains was determined. The minimal characters for the identification of strains of A . xylosoxidans are presented.A chromobacter xylosoxidans was named and described by Yabuuchi and Ohyama ( 1 3) after a study of seven strains isolated from purulent ear discharge of patients with chronic otitis media. The type strain, KM 543, was designated and deposited in several type-culture collections. Among 18 3 strains of nonfermenting, gram-negative rods received from several clinical laboratories since 1969, 35 were identified as A . xylosoxidans. Twenty strains received from foreign investigators were subsequently identified as A . xylosoxidans. The uniformity of the flagellar morphology, biochemical reactions, cellular lipid and fatty acid composition, and the guanine plus cytosine (GC) mole percent of composition deoxyribonucleic acid (DNA) serve to establish the homogeneity of A . xylosoxidans. The purposes of this report are to offer evidence of the uniformity of the species, to amend the previous description (1 3), and t o present the minimal characters for the identification of strains of A . xykosoxidans.
MATERIALS AND METHODSThe histories and corresponding accession numbers of 55 strains of A. xylosoxidans are listed in Table 1.Strains described in the literature (3, 6 , 9 ) are listed in Table 2.A . xylosoxidans ATCC 212 (= RH 137 = KM 1051) was isolated in 1923 and deposited in the American Type Culture Collection by E. 0. Jordan, University of Chicago, in 1925, and is the oldest strain of this species known to be available. The type strain, ATCC 27061 (KM 543), was isolated by H. Takeda, Kansai Medical University Hospital, from the purulent ear discharge of a 32-year-old female patient with otitis media chronica sinistra. It was isolated from a specimen collected during the patient's first visit for medical attention at Kansai Medical University Hospital on 8 July 1969, and was mixed with Sraphylococcus aureus. The unidentified glucose nonfermenter, strain 9, was received from Takeda on 30 September 1969 and was designated KM 543 (13).A broth culture was formalinized, washed twice with distilled water, and stained for flagella by the method of Leifson (7,8). A distilled-water suspension, prepared from growth on an infusion agar (Difco 0045) slant, was also stained for flagella. Growth from infusion agar w...