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05:57
In Vitro Assay of Bacterial Adhesion onto Mammalian Epithelial Cells
Published on: May 16, 2011
Flavobacterium columnare colony types: connection to adhesion and virulence?
Heidi M T Kunttu1, Lotta-Riina Suomalainen, E Ilmari Jokinen
1University of Jyväskylä, Department of Biological and Environmental Science, P.O. Box 35, FI-40014 Jyväskylä, Finland. hkunttu@jyu.fi
Microbial Pathogenesis
|November 6, 2008
Summary
Flavobacterium columnare exhibits four colony types, but molecular analysis shows no differences within strains. Virulence and adhesion varied, suggesting adhesion may not be the primary factor in columnaris disease.
Area of Science:
- Bacteriology
- Fish Pathology
- Molecular Biology
Background:
- Flavobacterium columnare causes columnaris disease in fish.
- Colony morphology can vary among bacterial strains.
- Understanding F. columnare colony types is crucial for disease management.
Purpose of the Study:
- To investigate the relationship between colony morphology, molecular characteristics, and virulence of Flavobacterium columnare.
- To assess the adhesion capabilities of different F. columnare colony types.
- To determine if adhesion is a key virulence factor in columnaris disease.
Main Methods:
- Culturing F. columnare on Shieh and AO agar to observe colony morphologies (types 1-4).
- Molecular characterization using Amplified Fragment Length Polymorphism (AFLP), Automated Ribosomal Intergenic Spacer Analysis (ARISA), and SDS-PAGE.
- Assessing virulence in rainbow trout fingerlings and adhesion to polystyrene and fish gills.
Main Results:
- Four distinct colony morphologies (types 1-4) were identified on Shieh agar.
- No molecular differences were found between colony types within the same strain.
- Type 1 colonies were most virulent, while type 2 showed highest adhesion to polystyrene; adhesion did not correlate with virulence.
- Multiple colony types were re-isolated from infected fish, indicating potential phase variation.
Conclusions:
- Strong adhesion capacity may not be the primary virulence factor for F. columnare.
- Colony morphology variations could be due to phase variation.
- Different colony types may play distinct roles during the infection process of columnaris disease.
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