Mycoplasma oxoniensis, a New Species Isolated from Chinese Hamster Conjunctivas

Abstract

Mycoplasmas which were distinct from Mycoplasma cricetuli were isolated from the conjunctivas of Chinese hamsters. Two clones, which were derived from a single colony and were obtained on separate occasions, were examined in detail for morphology, growth, and biochemical characteristics. These clones were indistinguishable from each other and had the following properties: guanine-plus-cytosine content of 29 mol% , requirement for sterol, facultatively anaerobic, and positive for glucose metabolism. They were serologically distinct from M . cricetuli and all 94 other previously described Mycoplasma and Acholepksma spp. One of them, strain 128 (= NCTC 11712), is designated the type strain of a new species, Mycoplasma oxoniensis.Previously, only one named Mycoplasma species has been isolated from Chinese hamsters. Mycoplasma cricetuli was isolated from the conjunctivas of Chinese hamsters in several animal colonies in the United Kingdom that were mostly derived from one original group (12, 14). M . cricetuli was also recovered from Chinese hamsters in The Netherlands (19a).Recently, other mycoplasma strains that appeared to be serologically and otherwise distinct from M . cricetuli were isolated from Chinese hamsters (unpublished data). In this paper I describe tests that were carried out to characterize two of these isolates in order to examine their relationships to each other and to M . cricetuli and also to provide the criteria necessary for determining whether they represent a new species (26). Other strains isolated had similar properties. MATERIALS AND METHODSMycoplasma strains. Mycoplasmas were isolated from the conjunctivas of Chinese hamsters from an animal colony on two separate occasions. A culture of each isolate was cloned to produce a pure culture by using a method involving initial filtration of a broth culture through a 300-nm-pore-size membrane filter, culturing of the filtrate on solid medium, transfer of a single resulting colony to another agar plate, and inoculation of the subsequent growth into broth. This whole procedure was repeated an additional four times; thus, the organisms were filter cloned five times (26). One of the clones was designated strain 12gT (T = type strain), and the other clone was designated strain 547.Mycoplasma species. The following Acholeplasma spp. type strains were used:Medium and growth conditions. The culture medium used has been described by and by Hill (11). The purified agar used in the growth medium was Lab M agar (Lab M, London, England). Depending on their biochemical activities, the mycoplasmas were grown in liquid medium containing 1% (wt/vol) glucose (pH 7.8) or in liquid medium containing 1% (wt/vol) arginine (pH 7.3). The species grown in medium containing arginine were not inhibited by 1% arginine. Agar cultures were incubated at 35 to 37°C either in a humid chamber or under anaerobic conditions in a GasPak system. Liquid cultures were stored at -70°C in ampules.Growth requirements and characteristics. subcultured onto solid medium and incubated for 1...

Bacterial species to be considered in quality assurance of mice and rats

“…However, enough information is available in order to identify a number of specific bacteria about which information on their status will be important for a range of research groups (Table 3). All of these, that is, Alistipes spp., 87 A. muciniphila , 88 bifidobacteria, 89 Bacteroides spp., 90 F. prausnitzii , 91 Prevotella spp. 92 and segmented filamentous bacteria (SFBs), 93 can be detected by PCR.…”