Journal of Bacteriology & Parasitology

Aeromonas salmonicida proliferation and quorum sensing in response to mucins isolated from Atlantic salmon skin and intestine

3^rd International Congress on Bacteriology and Infectious Diseases

August 04-06, 2015 Valencia, Spain

János Tamás Padra, Henrik Sundh, Chunsheng Jin, Niclas G Karlsson, Kristina Sundell and Sara K Lindén

Scientific Tracks Abstracts: J Bacteriol Parasitol

Abstract:

Aquaculture is a growing industry increasing the need for understanding host-pathogen interactions in fish. The skin and
mucosal surfaces covered by a mucus layer is the first point of contact between fish and pathogens. However, knowledge
on fish mucin-pathogen interactions is limited. A. salmonicida, the causative agent of furunculosis is a major infectious threat
to aquaculture. We previously demonstrated that the binding of A. salmonicida to Atlantic salmon mucins differ between body
sites and is dependent on the presence of the sialic acid: N-acetyl neuraminic acid on mucins. Here, we cultured A. salmonicida
in the presence of mucins purifiedfrom skin, pyloric caeca, proximal and distal intestine from five healthy Atlantic salmons
and analyzed growth rate and bacterial communication through quorum sensing molecules. Intestinal mucins enhanced A.
salmonicida growth, whereas skin mucins had no effect. The increase in growth was positively affected by longer glycan chains
of mucins and higher ratio of sialic acid. Enzymatic desialylation of mucins enhanced proliferation further. Mucins from all
sites decreased the production of autoinducer-II (AI-II) signal molecules. Desialylation organ specifically altered the level
of AI-II molecules produced by A. salmonicida. Thus, it appears that although mucins of the intestinal tract stimulated A.
salmonicida growth, presumably reflecting that the pathogen senses the right target niche, the sialylated mucin glycans seem
to act as a defense mechanism and limit the growth response. Mucin inhibition of QS may be an additional host defense
mechanism influenced by the level of sialylation on salmon mucins.

Biography :

János Tamás Padra has completed his PhD at the University of Debrecen, Hungary in 2012. Since then he is a Post-Doctoral member of Mucins in Infection and
Cancer team lead by Dr Sara K Lindén at Sahlgrenska Academy, University of Gothenburg, Sweden.