Helicobacter nemestrinae sp. nov., a Spiral Bacterium Found in the Stomach of a Pigtailed Macaque (Macaca nemestrina)

Abstract

A new microaerophilic, spirally curved, rod-shaped bacterium was isolated from the gastric mucosa of a pigtailed macaque (Macaca nemestrina). The gram-negative cells of this bacterium are oxidase, catalase, and urease positive and strongly resemble Helicobacter pylon' (Campylobacter pylon) cells. Like H. pylon', this organism does not metabolize glucose, does not reduce nitrate or produce indole, does not produce H,S from triple sugar iron agar, does not hydrolyze hippurate or esculin, and does not grow in the presence of 1% glycine, 1.5% salt, or 1% bile. Also like H. pylon', it is resistant to nalidixic acid and susceptible to cephalothin. However, unlike H. pylori, the colorless colonies are flat and have irregular edges. This organism has a unique cellular fatty acid composition, forming a new gas-liquid chromatography group, group K, and a distinctive DNA content (24 mol% guanine plus cytosine). It exhibits less than 10% DNA-DNA homology (as determined by the nylon filter blot method at 65°C) with other members of the genus Helicobacter. Although the levels of DNA relatedness between previously described Helicobacter species and the new organism are low (less than 10%) and the difference in guanine-plus-cytosine content is large (24 versus 36 to 41 mol%), the genus Helicobacter is the only genus in which it is logical to include the organism at this time. We propose that our single strain represents a new species, Helicobacter nemestn'nae, and we designate strain T81213-NTB (= ATCC 49396) as the type strain.Gastric spiral organisms belonging to the genus Campylobacter have been described in human and nonhuman primates (4, 5 , 16, 23, 24, 28, 31, 37) and in ferrets (8, 10, 11). In humans these organisms have been known as Campylobacter pylori, but RNA sequencing studies have shown clearly that they do not belong to the genus Campylobacter (19,29,32,35). Thompson et al. (35) suggested that C. pylori is closely related to Wolinella succinogenes. However, Goodwin et al. described sufficient phenotypic differences between these organisms to support transfer of C. pylori to a separate genus, and so C. pylori was renamed Helicobacter pylori and the ferret organism Campylobacter mustelae was renamed Helicobacter mustelae (13). These gram-negative bacilli colonize the mucus layer on the gastric epithelium. H. pylori has been associated with subclinical chronic gastritis in monkeys and with chronic nonautoimmune type B gastritis and possibly peptic ulcers in humans (1,4,6,7,14,17,24,27,30,37).A distinct Helicobacter species was removed from the gastric mucosa of a Macaca nemestrina male. The distinguishing features of this organism include the ability to grow at 42"C, a unique cellular fatty acid composition, and a distinctive DNA guanine-plus-cytosine (G + C) content (24 mol%), as well as less than 10% homology with H. pylori or H. mustelae (12,16). Colonization of the gastric mucosa by this organism was not associated with morbidity, mortality, or pathology in the monkey. We describe this new organism and propose...

Helicobacter nemestrinae ATCC 49396T is a strain of Helicobacter pylori (Marshall et al. 1985) Goodwin et al. 1989, and Helicobacter nemestrinae Bronsdon et al. 1991 is therefore a junior heterotypic synonym of Helicobacter pylori.

“…At present, the reason for the discrepancy between our data and the data published by Bronsdon et al (1991) and Sly et al (1993) is unclear. The 16S rDNA sequencing results were reproduced with a sample of ATCC 49396 T grown from a ' seed vial ' that was kindly provided by the ATCC and had been produced in the initial deposition process in 1990.…”

“…The beststudied of these is Helicobacter pylori, a prevalent human pathogen that colonizes the gastric mucus of more than half of the human population and causes chronic, often lifelong infections. Helicobacter nemestrinae T81213-NTB T (l ATCC 49396 T ) was isolated from a pigtailed macaque (Macaca nemestrina) and has been reported to be closely related to H. pylori (Bronsdon et al, 1991 The GenBank/EMBL/DDBJ accession numbers for the sequences reported in this paper are AJ421784-AJ421792.…”

Identification of structures containing polyphosphate in Helicobacter pylori

“…mustelae, H. felis, H. suis, H. nemestrinae and H . heilmannii Fox & Lee, 1989;Bronsdon et al, 1991;Paster et al, 1991).…”

Species differentiation and identification in the genus ofHelicobacter

“…pylori was, therefore, transferred to the new genus and renamed as Helicobacter pylori. The major features [15,29] of Helicobacter genus consist of Helical, curved or straight unbranched morphology.…”