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Published on: January 8, 2020
Two mobile Pectobacterium atrosepticum prophages modulate virulence
Terry J Evans1, Sarah J Coulthurst, Evangelia Komitopoulou
1Department of Biochemistry, University of Cambridge, Cambridge, UK.
FEMS Microbiology Letters
|February 12, 2010
Summary
Pectobacterium atrosepticum prophages ECA41 and ECA29 influence bacterial virulence. Deleting these prophages reduced virulence in potato plants and decreased swimming motility, but did not impact growth or enzyme secretion.
Area of Science:
- Bacteriology
- Microbial Genetics
- Plant Pathology
Background:
- The Pectobacterium atrosepticum strain SCRI1043 genome harbors two complete prophages: ECA41 (Mu-like) and ECA29 (P2 family).
- Both prophages possess the capability to integrate into and excise from the bacterial genome.
Purpose of the Study:
- To investigate the functional role of prophages ECA41 and ECA29 in Pectobacterium atrosepticum.
- To determine the impact of prophage deletion on bacterial growth, motility, enzyme secretion, and virulence.
Main Methods:
- Genetic manipulation to create deletion mutants for individual and combined prophages (ECA41, ECA29).
- Assays to evaluate bacterial growth rates, secretion of plant cell wall-degrading enzymes, and swimming motility.
- Virulence assays using a potato host model.
Main Results:
- Prophage excision was observed but was rare, and spontaneous lysis was not induced.
- Deletion of prophages did not affect bacterial growth rate or the secretion of plant cell wall-degrading enzymes.
- Swimming motility was significantly decreased in prophage deletion strains.
- Virulence of prophage deletion strains in potato was reduced compared to the wild-type.
Conclusions:
- Prophages ECA41 and ECA29 play a role in the virulence of Pectobacterium atrosepticum.
- These prophages contribute to bacterial swimming motility, which may be linked to host plant infection.
- Further research is warranted to elucidate the precise mechanisms by which these prophages affect virulence.
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