1-octanol, a self-inhibitor of spore germination in Penicillium camemberti

Guillaume Gillot (1) , Nicolas Decourcelle (1) , Gaëlle Dauer (1) , Georges Barbier (1) , Emmanuel Coton (1) , David Delmail (2) , Jérôme Mounier (1)

1 LUBEM - Laboratoire Universitaire de Biodiversité et Ecologie Microbienne
2 ISCR - Institut des Sciences Chimiques de Rennes

Penicillium camemberti is a technologically relevant fungus used to manufacture mould-ripened cheeses. This fungal species produces many volatile organic compounds (VOCs) including ammonia, methyl-ketones, alcohols and esters. Although it is now well known that VOCs can act as signaling molecules, nothing is known about their involvement in P. camemberti lifecycle. In this study, spore germination was shown to be self-regulated by quorum sensing in P. camemberti. This phenomenon, also called the "crowding effect", is population-dependent (i.e. observed at high population densities). After determining the volatile nature of the compounds involved in this process, 1-octanol was identified as the main compound produced at high-spore density using GC-MS. Its inhibitory effect was confirmed in vitro and 3 mM 1-octanol totally inhibited spore germination while 100 μM only transiently inhibited spore germination. This is the first time that self-inhibition of spore germination is demonstrated in P. camemberti. The obtained results provide interesting perspectives for better control of mould-ripened cheese processes

Keywords: Penicillium camemberti; quorum sensing; Cheese; 1-octanol; germination

Domains: Life Sciences [q-bio]; Microbiology and Parasitology; Mycology; Life Sciences [q-bio]; Food engineering

Guillaume Gillot, Nicolas Decourcelle, Gaëlle Dauer, Georges Barbier, Emmanuel Coton, et al.. 1-octanol, a self-inhibitor of spore germination in Penicillium camemberti. Food Microbiology, 2016, 57, pp.1-7. ⟨10.1016/j.fm.2015.12.008⟩. ⟨hal-01254795⟩