Induction and characterization of lysogenic bacteriophages from Streptococcus iniae
Article first published online: 4 APR 2013
© 2013 The Society for Applied Microbiology
Journal of Applied Microbiology
Volume 114, Issue 6, pages 1616–1624, June 2013
How to Cite
Wright, E.E., Elliman, J.R. and Owens, L. (2013), Induction and characterization of lysogenic bacteriophages from Streptococcus iniae. Journal of Applied Microbiology, 114: 1616–1624. doi: 10.1111/jam.12192
- Issue published online: 17 MAY 2013
- Article first published online: 4 APR 2013
- Accepted manuscript online: 12 MAR 2013 03:41PM EST
- Manuscript Accepted: 7 MAR 2013
- Manuscript Revised: 4 MAR 2013
- Manuscript Received: 27 DEC 2012
- Siphoviridae ;
- Streptococcus iniae
To investigate the presence of prophage in Streptococcus iniae, a highly problematic fish pathogen.
Methods and Results
Cross-spotting assays and mitomycin C inductions were conducted to screen for prophage in 48 Strep. iniae isolates. Bacteriophages were characterized by plaque assays, transmission electron microscopy and DNA restriction enzyme digestion. Plaque assays confirmed prophages in 14·6% of isolates. Phages vB_SinS-44, vB_SinS-45, vB_SinS-46 and vB_SinS-48 lysed 78·5% of Strep. iniae isolates and displayed distinctive host ranges. Microscopy revealed virions exhibiting long, non-contractile tails and isometric heads consistent with phages from the family Siphoviridae. Restriction digests revealed genome sizes ranging from 27·5 to 66·3 kbp, with distinct cutting patterns that indicate the presence of related prophages in bacteria isolated from different geographic regions.
The rate of prophage carriage found is comparably low and induction rates varied between phages. The four characterized Siphoviridae phages have broad host ranges within the Strep. iniae isolates.
Significance and Impact of the Study
This is the first description and characterization of lysogenic phages from Strep. iniae. These phages are candidates for research and diagnosis of the bacterium and their identification should accelerate the discovery of lytic phages to be trialled against Strep. iniae infections in fish.