Reciprocal immune benefit based on complementary production of antibiotics by the leech Hirudo verbana and its gut symbiont Aeromonas veronii

• DOI: 10.1038/srep17498
• Publication Date: 2015-12-04T10:05:25Z
• Authors: Aurélie Tasiemski; François Massol; Virginie Cuvillie...; Céline Boidin-Wic...; Emmanuel Roger; Franck Rodet; Isabelle Fournier; Frédéric Thomas; Michel Salzet
• Keywords: Aeromonas veronii; Commensalism

Abstract The medicinal leech has established a long-term mutualistic association with Aeromonas veronii, versatile bacterium which can also display free-living waterborne and fish- or human-pathogenic lifestyles. Here, we investigated the role of antibiotics in dynamics interaction between its gut symbiont . By combining biochemical molecular approaches, isolated identified for first time antimicrobial peptides (AMPs) produced by digestive tract Immunohistochemistry data PCR analyses evidenced that AMP genes are induced epithelial cells when load is low (starved animals), while repressed abundance highest (post blood feeding). asynchronous production AMPs both partners suggests these antibiotic substances (i) provide them reciprocal protection against invasive bacteria (ii) contribute to unusual simplicity microflora leech. This immune benefit substantially reinforces evidence an evolutionarily stable H. verbana A. veronii Altogether may insights into processes making species either deleterious beneficial.