Phylum Proteobacteria, Class Epsilonproteobacteria, Order Campylobacterales, Family Campylobacteraceae, Genus Campylobacter,
Campylobacter, gracilis (Tanner et al. 1981) Vandamme et al. 1995.
Basonym: Bacteroides gracilis Tanner et al. 1981.
Gram-negative cells, small and straight, 0.4-4 x 6 μm, with rounded or tapered ends.
Colonies vary from small pinpoint, 1 mm in diameter to spreading colonies up to 5
mm in diameter. Agar pitting is medium dependent, negative in anaerobic, 3-days-old
cultures on 5% blood agar. Translucent colonies are produced on blood agar base.
Does not grow microaerobically on common agar bases in an atmosphere without
hydrogen. Does not grow in semisolid medium (0.16% agar), in air, or in an
atmosphere containing O2:CO2:N2 (5:10:85). Growth is stimulated in broth cultures by
formate and fumarate.
Strains grow in the presence of 0.1% potassium permanganate, 1% glycine and
0.05% basic fuchsin but not in the presence of 0.04% triphenyl-tetrazolium chloride,
64 mg/l cefoperazone, or 2% ox bile. A few strains (14%) grow on 0.01% Janus green
medium and in 2% NaCl. No growth at 25 ºC.
Isolated from gingival crevices and from various infections; soft tissue abscesses, pneumonia, empyema and wound in humans.
Associated with with deep tissue infection in humans.
- Don J. Brenner and J.J. Farmer III, 2001. Family I. Campylobacteraceae. In: Bergey’s Manual of Systematic Bacteriology, Second
edition,Vol 2, part C, George M. Garrity (Editor-in-Chief), pp 1145-1168.
- P. Vandamme, M. I. Daneshvar, F. E. Dewhirst, B. J. Paster, K. Kersters, H. Goossens, and C. W. Moss. Chemotaxonomic
Analyses of Bacteroides gracilis and Bacteroides ureolyticus and Reclassification of B. gracilis as Campylobacter gracilis comb.
nov. Int J Syst Bacteriol January 1995 45:145-152.
Usually positive results for indoxyl acetate hydrolysis & nitrate reduction.
Negative results for oxidase, catalase (most strains), urea hydrolysis, hippurate hydrolysis, selenite reduction & H2S production on
TSI. No carbohydrates fermentation.
(c) Costin Stoica