Phylum Proteobacteria, Class Gammaproteobacteria, Order Pseudomonadales, Family Moraxellaceae, Genus Moraxella, Moraxella
atlantae Bovre et al. 1976.
Gram negative rods, variable in shape and size (1-2 μm), with little tendency to form
chains. No swimming motility. Cells are often fimbriated and may show “twitching
motility”. Not encapsulated. Does not form poly-beta-hydroxybutyrate inclusions.
Colonies are small (0.2–0.5 mm in diameter, occasionally up to 1 mm) in 48 hours
on either blood agar or chocolate agar. Agar corrosion and spreading of colonies may
be seen. Colonies are semiopaque and may appear slightly pink, probably due to
blood pigment accumulation. Not pigmented. Non-hemolytic. Bile salts (or Tween 80)
stimulation of growth occurs with levels up to 1%. No growth at 4 or 42 ºC. Slight
growth at 22 ºC, optimum temperature for growth 33 to 37 ºC. Strict aerobe, not
distinctly stimulated by CO2, or humidity. Grows on MacConkey agar. No growth on
minimal medium containing ammonium and acetate.
Isolated from human blood, cerebrospinal fluid, and spleen. The natural habitat is not certain.
- Elliot Juni and Kjell Bovre: Order IX Pseudomonadales Orla-Jensen 1921, Family II Moraxellaceae Rossau, Van Landschoot,
Gillis and De Ley 1991 In: Bergey’s Manual of Systematic Bacteriology, Second edition,Vol two, part B, George M. Garrity (Editor-in-
Chief), pp. 411-442.
- K. Bovre, J. E. Fuglesang, N. Hagen, E. Jantzen, and L. O. Froholm. Moraxella atlantae sp. nov. and Its Distinction from Moraxella
phenylpyrouvica. Int J Syst Bacteriol October 1976 26:511-521.
- Gabriel Ionescu, Delia Berceanu-Vaduva: Cocobacili Gram negativi nefermentativi. In: (Eds.) Dumitru Buiuc, Marian Negut. Tratat
de microbiologie clinica, ed. a III-a, cap. 32.2, 787-795.
Positive results for alkaline phosphatase, acid phosphatase, catalase, esterase & oxidase.
Negative results for DN-ase, citrate utilization, nitrate and nitrite reduction, coagulated serum liquefaction, gelatin hydrolysis, indole
production, H2S production, lysine decarboxylase, ornithine decarboxylase, phenylalanine deaminase, tryptophan deaminase &
urease. No acid production from carbohydrates.
(c) Costin Stoica