Emergence of a novel Shigella flexneri serotype 4s strain that evolved from a serotype X variant in China.
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ABSTRACT:
SUBMITTER: Qiu S
PROVIDER: S-EPMC3067715 | biostudies-literature | 2011 Mar
REPOSITORIES: biostudies-literature
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Emergence of a novel Shigella flexneri serotype 4s strain that evolved from a serotype X variant in China.
Qiu Shaofu S Wang Zhongqiang Z Chen Chen C Liu Nan N Jia Leili L Liu Wenjing W Wang Ligui L Hao Rongzhang R Zhang Ling L Wang Yong Y Song Hongbin H
Journal of clinical microbiology 20101222 3
This paper describes the first isolation of a new Shigella flexneri serotype, designated 4s, in Beijing, China. Genotypic and phenotypic profiling suggests that this isolate is a clone of the S. flexneri serotype X variant reference strain. Of particular concern is the multidrug resistance exhibited by this isolate. ...[more]
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Project description:BackgroundShigella flexneri is the major pathogen causing bacillary dysentery. Fifteen serotypes have been recognized up to now. The genesis of new S. flexneri serotypes is commonly mediated by serotype-converting bacteriophages. Untypeable or novel serotypes from natural infections had been reported worldwide but have not been generated in laboratory.ResultsA new S. flexneri serotype-serotype 1 d was generated when a S. flexneri serotype Y strain (native LPS) was sequentially infected with 2 serotype-converting bacteriophages, SfX first and then SfI. The new serotype 1 d strain agglutinated with both serotype X-specific anti-7;8 grouping serum and serotype 1a-specific anti- I typing serum, and differed from subserotypes 1a, 1b and 1c. Twenty four S. flexneri clinical isolates of serotype X were all converted to serotype 1 d by infection with phage SfI. PCR and sequencing revealed that SfI and SfX were integrated in tandem into the proA-yaiC region of the host chromosome.ConclusionsThese findings suggest a new S. flexneri serotype could be created in nature. Such a conversion may be constrained by susceptibility of a strain to infection by a given serotype-converting bacteriophage. This finding has significant implications in the emergence of new S. flexneri serotypes in nature.
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