Phylum Proteobacteria, Class Epsilonproteobacteria, Order Campylobacterales, Family Campylobacteraceae, Genus Arcobacter,
Arcobacter halophilus Donachie et al. 2005.
Gram-negative, slightly curved rods, becoming helical as cells lengthen, 0.4-0.5 x 1.5-
2.5 μm. Motile by means of a polar flagellum.
Colonies are smooth, off-white, circular with entire margins, convex, non-swarming
with a sticky consistency and approximately 1–2 mm in diameter after 72 hours
incubation at 18–22 ºC under microaerobic conditions on 5% blood agar containing
3.5% NaCl. Nonhemolytic.
Obligately halophilic; does not grow, or grows only poorly, on media that contain less
than 2%NaCl or less than 0.1% KNO3.
Growth is not observed under microaerobic conditions on media containing 0.04%
triphenyl-tetrazolium chloride, 1% glycine, 0.1% potassium permanganate, 0.001%
sodium arsenite, 0.02–0.05% safranin, 32 mg/L nalidixic acid, 32 mg/L cephalothin,
32 mg/L carbenicillin, 64mg/L cefoperazone, 0.032% methyl orange, 0.1% sodium
deoxycholate, 0.005% basic fuchsin, 00005% crystal violet, 0.01% janus green, 0.1%
sodium fluoride or 0.2% pyronin.
When tested on 5% blood agar containing 3.5% NaCl, growth is observed under aerobic and microaerobic conditions at room
temperature and at 37 ºC, and under anaerobic conditions at 37 ºC. Growth is not observed on 5% blood agar containing
3.5% NaCl under microaerobic conditions at 42 ºC. Grows microaerobically on 5% BA containing 2–4% (w/v) NaCl. Growth is not
observed under microaerobic conditions on nutrient, charcoal, minimal, MacConkey, potato starch, lecithin, tyrosine or casein media.
Isolated from water collected from a hypersaline lagoon on Laysan Atoll in the north-western Hawaiian Islands.
- Stuart P. Donachie, John P. Bowman, Stephen L. W. On, and Maqsudul Alam. Arcobacter halophilus sp. nov., the first obligate
halophile in the genus Arcobacter. Int J Syst Evol Microbiol May 2005 55:1271-1277.
- Luis Collado and Maria José Figueras. Taxonomy, Epidemiology, and Clinical Relevance of the Genus Arcobacter. Clin. Microbiol.
Rev. 2011, 24(1):174.
Positive results for oxidase, nitrate reduction, & indoxyl acetate hydrolysis.
Negative results for catalase, urease, alkaline phosphatase, hippurate hydrolysis, DN-ase & H2S production on TSI.
(c) Costin Stoica