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09:28
A Microfluidic Device for Quantifying Bacterial Chemotaxis in Stable Concentration Gradients
Published on: April 19, 2010
Flavobacterium columnare chemotaxis to channel catfish mucus
Phillip H Klesius1, Craig A Shoemaker, Joyce J Evans
1Aquatic Animal Health Research Laboratory, US Department of Agriculture, Agriculture Research Service, Auburn, AL 36830, USA. phillip.klesius@ars.usda.gov
FEMS Microbiology Letters
|September 20, 2008
Summary
Flavobacterium columnare bacteria are attracted to channel catfish mucus, especially from the skin. This chemotaxis is stronger in the more virulent genomovar II, suggesting a role in fish disease.
Area of Science:
- Fish pathology
- Bacterial chemotaxis
- Aquatic microbiology
Background:
- Flavobacterium columnare is a Gram-negative fish pathogen affecting various fish species.
- Isolates from channel catfish are classified into genomovar I and II, with genomovar II being more virulent.
- Understanding bacterial chemotaxis is crucial for fish disease management.
Purpose of the Study:
- To investigate chemotactic responses of Flavobacterium columnare genomovars to channel catfish mucus.
- To compare responses to mucus from different anatomical locations (skin, gills, intestines).
- To determine if chemotaxis differs between virulent (genomovar II) and less virulent (genomovar I) F. columnare isolates.
Main Methods:
- Capillary chemotaxis assay was employed.
- Mucus was collected from the skin, gills, and intestines of healthy channel catfish.
- Chemotactic responses of F. columnare genomovar I and II isolates were measured.
Main Results:
- F. columnare exhibited a chemotactic response to channel catfish mucus.
- Skin and gill mucus elicited a stronger chemotactic response than intestinal mucus.
- Sixty percent of skin mucus samples induced a positive chemotactic response.
- Genomovar II isolates showed a significantly greater chemotactic response to skin mucus compared to genomovar I isolates.
Conclusions:
- Channel catfish mucus, particularly skin mucus, attracts Flavobacterium columnare.
- Chemotaxis towards mucus may be a critical initial step in F. columnare colonization of fish.
- The enhanced chemotaxis of genomovar II isolates suggests a link between chemotaxis and virulence in F. columnare.
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