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. 2020 Aug;28(8):696-697.
doi: 10.1016/j.tim.2020.02.011. Epub 2020 Apr 8.

Shigella sonnei

Vincenzo Torraca  1 , Kathryn Holt  2 , Serge Mostowy  3
Affiliations

Shigella sonnei

Vincenzo Torraca et al. Trends Microbiol. 2020 Aug.
No abstract available

Keywords: O-antigen; antimicrobial resistance; bacillary dysentery; type VI secretion system.

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Figures

Figure 1
Figure 1. Epidemiology of Shigella sonnei.
(A) Cases of S. sonnei versus Shigella flexneri. Cases of S. sonnei are increasing globally. Red indicates countries where S. sonnei is the dominant cause of shigellosis (when compared with S. flexneri). Blue indicates countries where a higher proportion of S. flexneri is still being reported (although S. sonnei cases may be rapidly increasing). Data presented according to Thompson et al. (see Literature). (B) Distribution of S. sonnei resistance to first- and second-line antibiotics. FQR, fluoroquinolone resistance; ESBL, extended-spectrum β-lactamase-producing (i.e., resistant to third-generation cephalosporins or carbapenems); RSA, reduced sensitivity to azithromycin. Countries are colored according to antibiotic-resistant cases reported in Table S1 in the supplemental information online.
Figure 2
Figure 2. Shigella sonnei Virulence Determinants.
(A) S. sonnei 53G platedon Congo Red agar.Thevirulenceplasmid (pINV) of S. sonnei is essential for pathogenesis in vivo but is unstable outside the host (and is lost when bacteria are cultured in vitro). As a result of maintenance or loss of pINV, S. sonnei presents two different phenotypes on Congo Red plates. Black arrows indicate small smooth red colonies (Phase I S. sonnei). These colonies retain pINV and accumulate Congo Red dye because they express a type III secretion system (T3SS). The small smooth phenotype is due to expression of O-antigen (O-Ag). White arrows indicate large rough white colonies (Phase II S. sonnei). These colonies are unable to accumulate Congo Red and have an irregular shape because they lose pINV (which encodes both T3SS and O-Ag). In this case, bacteria were plated from a glycerol stock (originally obtained from a liquid culture of a single Phase I colony) and incubated overnight at 37°C. Grid numbers indicate the size in centimetres. (B) Schematic representing key S. sonnei virulence determinants. S. sonnei encodes a T3SS crucial for host cell invasion; IcsAwhich mediates actin-based motility; aT6SS crucial for bacterial competition and niche occupancy; a horizontally acquired g4c capsule and O-antigen involved in resistance to phagocytosis, complement-mediated lysis, and phagolysosomal degradation. L-AltNAc, 2-acetamido-2-deoxy-L-altruronic acid; D-FucNAc, N-acetyl-2-acetamido-4-amino-2,4-dideoxy-D-fucose. Figure adapted from Torraca et al. (see Literature).
See this image and copyright information in PMC

References

    1. Anderson MC, et al. Shigella sonnei encodes a functional T6SS used for interbacterial competition and niche occupancy. Cell Host Microbe. 2017;21:769–776.:e3. - PubMed
    1. Baker KS, et al. Intercontinental dissemination of azithromycin-resistant shigellosis through sexual transmission: A cross-sectional study. Lancet Infect Dis. 2015;15:913–921. - PubMed
    1. Baker KS, et al. Horizontal antimicrobial resistance transfer drives epidemics of multiple Shigella species. Nat Commun. 2018;9:1462. - PMC - PubMed
    1. Caboni M, et al. An O-antigen capsule modulates bacterial pathogenesis in Shigella sonnei. PLoS Pathog. 2015;11:e1004749. - PMC - PubMed
    1. Chung The H, et al. Dissecting the molecular evolution of fluoroquinolone-resistant Shigella sonnei. Nat Commun. 2019;10:4828. - PMC - PubMed

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