Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1992 Jan;30(1):172-5.
doi: 10.1128/jcm.30.1.172-175.1992.

Characterization and classification of strains of Francisella tularensis isolated in the central Asian focus of the Soviet Union and in Japan

Affiliations

Characterization and classification of strains of Francisella tularensis isolated in the central Asian focus of the Soviet Union and in Japan

G Sandström et al. J Clin Microbiol. 1992 Jan.

Abstract

The two subspecies of Francisella tularensis, F. tularensis subsp. tularensis (type A) and F. tularensis subsp. palaearctica (type B), differ from each other in biochemistry and virulence. Strains of F. tularensis subsp. tularensis are believed to be confined to North America, whereas strains of F. tularensis subsp. palaearctica occur in Europe, in Asia, and in North America. Moreover, the existence of two other subspecies, designated F. tularensis subsp. mediaasiatica and F. tularensis subsp. palaearcitica japonica, has been suggested for strains of F. tularensis isolated in the central Asian focus of the Soviet Union and in Japan, respectively. In the present study, strains biochemically classified as F. tularensis subsp. mediaasiatica or F. tularensis subsp. palaearctica japonica have been investigated by hybridization with probes specific to 16S rRNAs of the two main subspecies. Furthermore, the virulence and biochemical characteristics of the strains were compared with those of strains belonging to F. tularensis subsp. palaearctica and F. tularensis subsp. tularensis. It was found that 16S rRNAs of F. tularensis subsp. mediaasiatica and F. tularensis subsp. palaearctica japonica hybridize with the probe specific to a genotype proposed herein, genotype A (F. tularensis subsp. tularensis), which shows that strains genetically related to this subspecies are found outside North America. However, the central Asian strains differed from F. tularensis subsp. palaearctica and F. tularensis subsp. tularensis strains when investigated by fermentation of glucose. The results of the biochemical tests could not be unambiguously used for differentiation of strains into F. tularensis subsp. palaearctica or F. tularensis subsp. tularensis. These drawbacks suggest that classification of strains of Francisella on the basis of 16S rRNA analysis may be preferable to classification on the basis of biochemical analysis.

PubMed Disclaimer

References

    1. Appl Environ Microbiol. 1990 Apr;56(4):949-55 - PubMed
    1. N Engl J Med. 1969 Dec 4;281(23):1310 - PubMed
    1. Gene. 1986;46(2-3):287-90 - PubMed
    1. Rev Infect Dis. 1989 May-Jun;11(3):440-51 - PubMed
    1. Appl Environ Microbiol. 1989 Aug;55(8):1907-10 - PubMed

LinkOut - more resources