Campylobacter mustelae, a New Species Resulting from the Elevation of Campylobacter pylori subsp. mustelae to Species Status

Abstract

The name Campylobacter pylori subsp. mustelae was recently proposed for strains belonging to the genus Campylobacter that were isolated from the gastric mucosa of ferrets because of the high levels of deoxyribonucleic acid relatedness (85 to 100%) of these strains to the type strain of Campylobacter pylori. Subsequent deoxyribonucleic acid relatedness studies done independently in three laboratories by three different methods indicate that the original results were in error. Strains isolated from ferrets in the United States, England, and Australia are members of a single species that is substantially different from C. pylori (10 to 20% relatedness at 50°C and 3 to 10% relatedness at 65°C as determined by the hydroxyapatite method; less than 10% relatedness at 65°C as determined by the nylon membrane blot method; and 30 to 49% relatedness at 66 to 68°C as determined by the spectrophotometric method). The strains isolated from ferrets also differ from human C. pylori strains in their ability to reduce nitrates, their negative leucine arylamidase reaction, their susceptibility to nalidixic acid, and their resistance to cephalothin. The strains from ferrets possess both polar and lateral flagella, whereas only polar flagella have been demonstrated in human C. pylori strains. Thus, the strains isolated from ferrets are members of a species that is distinct from C . pylori, and we propose elevating C. pylori subsp. mustelae to species status as Campylobacter mustelae sp. nov.

Transfer of Campylobacter pylori and Campylobacter mustelae to Helicobacter gen. nov. as Helicobacter pylori comb. nov. and Helicobacter mustelae comb. nov., Respectively

“…Causes gastritis and peptic ulceration in adult animals. The type strain is strain R85-13-6 (= ATCC 43772) (15), which has a G+C content of 35.5 +. 0.8 mol%.…”

“…DNA hybridization was performed by two methods. The nylon filter blot method (method P) was used in Perth, Australia (15). Briefly, DNA was extracted and purified as described by Majewski and Goodwin (31); samples were denatured by boiling and blotted in triplicate onto a positively charged nylon membrane (Biotrace; Gelman Sciences, Inc., Ann Arbor, Mich.), and the membranes were baked at 80°C for 1 to 2 h to immobilize the DNA.…”

“…However, in Perth, our DNA-DNA hybridization studies yielded a much lower degree of homology, indicating a more distant relationship; this finding was subsequently confirmed by the original workers. Other important taxonomic features distinguish C. pylori and the ferret organism, and the latter organism has now been elevated to species status as Cumpylobacter mustelae (15).…”

Comparative ultrastructural and functional studies of Helicobacter pylori and Helicobacter mustelae flagellin mutants: both flagellin subunits, FlaA and FlaB, are necessary for full motility in Helicobacter species

“…These results show that the presence of both flagellin subunits is necessary for complete motility of Helicobacter species. The importance of this flagellar organization for the ability of the bacteria to colonize the gastric mucosa and to persist in the gastric mucus remains to be proven.Helicobacter mustelae is a close relative of the human pathogen Helicobacter pylori and naturally colonizes the stomachs of ferrets (17,39). It has raised particular interest as an animal model for human H. pylori infection because its colonization patterns and histology and the resulting chronic lifelong disease bear a close resemblance to the human type B gastritis caused by H. pylori (16,18).…”

Helicobacter species and in vivo models of gastrointestinal cancer

“…Helicobacter mustelae, a natural gastric pathogen of ferrets, has many biochemical, molecular and phenotypic characteristics similar to those of H.pylori. 118,119 For example, H. mustelae is urease positive and motile and adheres to gastric mucosa using similar adhesin receptors to those utilized by H. pylori. H. pylori appears to have a limited host range of natural infection; this species naturally colonizes human, non-human primates, and cats.…”