P8 The marine environment as source of quorum sensing inhibitors

P8 The marine environment as source of quorum sensing inhibitors

Andrea Muras1, Celia Mayer1, Sarah Ikediashi1, Manuel Romero1 and Ana Otero1

1Microbioloxía E Parasitoloxía, Universidade De Santiago De Compostela, Santiago De Compostela, ESP

Quorum sensing (QS) is used by bacteria to coordinate the expression of genes involved in many key physiological processes mainly related to environment adaptation and pathogenesis. Enzymatic interference with these signalling systems, known as Quorum Quenching (QQ), has been explored as a novel anti-pathogenic therapy to control bacterial infections with positive results in plants, aquaculture and more recently in biomedicine.

Given the suitability of spore-producing bacterial species for biotechnological applications, 155

thermo-resistant bacteria isolated from macroalgae were screened for QQ activity against Nacyl-homoserine lactone (AHL) QS signals. Nine out of them presented wide-spectrum QQ activity. Further characterization of the QQ strains revealed that most isolates present an AiiA-like AHL lactonase.

This study shows that QQ is a common feature among cultivable marine bacteria and confirms the marine environment and more specifically macroalgae as an important source for anti-AHL compounds. Moreover, the thermo-resistance shown by the isolates used in this study enhances their potential biotechnological applications.