Phylum Proteobacteria, Class Epsilonproteobacteria, Order Campylobacterales, Family Helicobacteraceae, Genus Helicobacter,
Helicobacter felis Paster et al. 1991.
Gram-negative, tightly coiled helical rods, 0.4 x 5–7.5 μm. Coccoid forms appear in
old cultures. Rapid, corkscrew-like motility by means of 10-17 sheathed flagella in a
bipolar arrangement. Cells of most strains are surrounded by periplasmic fibers,
which appear as concentric helical ridges on the cell surface, either in pairs, threes,
Grows as a thin, translucent film on enriched blood agar and does not readily form
colonies. Colonies when observed are pinpoint and colorless after 3 days growth.
Highly fastidious. Can be cultured using serum-enriched broths (brain-heart infusion
and Brucella broths have been used), in which growth is enhanced by shaking the
culture. Some strains can grow on solid media under anaerobic conditions. Grow at
37 and 42 ºC (variable) but not at 25 ºC. Most strains are resistant to 5-fluorouracil
(100 U/l). No growth in 1.5% NaCl.
Isolated from the canine and feline gastric mucosal samples (apparently more frequent in felines). One strain was isolated from
human gastric biopsy. Susceptible to cephalothin, ampicillin, erythromycin, metronidazole, and bismuth compounds. Resistant to
Infection associated with lymphoid follicles in experimentally infected dogs. Colonizes the gastric mucosa of mice and may cause a
persistent chronic gastritis of approximately 1 year in duration in germ-free mice and their conventional non-germ-free counterparts.
Widely used as an experimental model, including for vaccine studies.
- George M. Garrity, Julia A. Bell and Timothy Lilburn, 2001. Family II. Helicobacteraceae. In: Bergey’s Manual of Systematic
Bacteriology, Second edition, Vol 2, part C, George M. Garrity (Editor-in-Chief), pp 1168-1195.
- B. J. Paster, A. Lee, J. G. Fox, F. E. Dewhirst, L. A. Tordoff, G. J. Fraser, J. L. O'Rrourke, N. S. Taylor, and R. Ferrero. Phylogeny of
Helicobacter felis sp. nov., Helicobacter mustelae, and Related Bacteria. Int J Syst Bacteriol January 1991 41:31-38.
- Katri Jalava, M. Kaartinen, M. Utriainen, I. Happonen, and M.-L. Hanninen. Helicobacter salomonis sp. nov., a Canine Gastric
Helicobacter sp. Related to Helicobacter felis and Helicobacter bizzozeronii. Int J Syst Bacteriol October 1997 47:975-982.
H. felis, H. bizzozeronii, and H. salomonis are biochemically and 16S rRNA gene sequence very similar.
Positive results for catalase, oxidase, urease (may be lost after subcultivation), nitrate reduction, arginine aminopeptidase, leucine
aminopeptidase, and gamma-glutamyl transpeptidase.
Negative results for N-acetylglucosaminidase, alpha-glucosidase, alpha-arabinosidase, beta-glucosidase, alpha-fucosidase,
alpha-galactosidase, beta-galactosidase, proline aminopeptidase, pyroglutamic acid amylamidase, tyrosine aminopeptidase,
alanine aminopeptidase, phenylalanine aminopeptidase, glycine aminopeptidase, arginine dihydrolase, hippurate hydrolysis, indoxyl
acetate hydrolysis, indole production, H2S production, and tolerance to 1% glycine.
Variable results for histidine and leucine aminopeptidase activity.
(c) Costin Stoica