UV-Sensitivity of Shiga Toxin-Converting Bacteriophage Virions Φ24B, 933W, P22, P27 and P32

Toxins

Sylwia Bloch¹  Bo៎na Nejman-Faleᑌzyk¹  Gracja Topka¹  Aleksandra Dydecka¹  Katarzyna Licznerska¹  Magdalena Narajczyk⁴  Agnieszka Necel¹  Alicja Węgrzyn³  Grzegorz Węgrzyn¹  Gerald B. Koudelka² 

[1] Department of Molecular Biology, University of Gdańsk, Wita Stwosza 59, Gdańsk 80-308, Poland; E-Mails:Department of Molecular Biology, University of Gdańsk, Wita Stwosza 59, Gdańsk 80-308, Poland;;Laboratory of Molecular Biology (affiliated with the University of Gdańsk), Polish Academy of Sciences, Wita Stwosza 59, Gdańsk 80-308, Poland; E-Mail:;Laboratory of Electron Microscopy, University of Gdańsk, Wita Stwosza 59, Gdańsk 80-308, Poland; E-Mail:

关键词: Shiga toxin-converting bacteriophages;    virion stability;    UV irradiation;   

DOI  :  10.3390/toxins7093727

来源: mdpi

【 摘 要 】

Shiga toxin-converting bacteriophages (Stx phages) are present as prophages in Shiga toxin-producing Escherichia coli (STEC) strains. Theses phages can be transmitted to previously non-pathogenic E. coli cells making them potential producers of Shiga toxins, as they bear genes for these toxins in their genomes. Therefore, sensitivity of Stx phage virions to various conditions is important in both natural processes of spreading of these viruses and potential prophylactic control of appearance of novel pathogenic E. coli strains. In this report we provide evidence that virions of Stx phages are significantly more sensitive to UV irradiation than bacteriophage λ. Following UV irradiation of Stx virions at the dose of 50 J/m², their infectivity dropped by 1–3 log₁₀, depending on the kind of phage. Under these conditions, a considerable release of phage DNA from virions was observed, and electron microscopy analyses indicated a large proportion of partially damaged virions. Infection of E. coli cells with UV-irradiated Stx phages resulted in significantly decreased levels of expression of N and cro genes, crucial for lytic development. We conclude that inactivation of Stx virions caused by relatively low dose of UV light is due to damage of capsids that prevents effective infection of the host cells.

【 授权许可】

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© 2015 by the authors; licensee MDPI, Basel, Switzerland.