Importance of quorum sensing crosstalk in the brown alga epimicrobiome.

Brown macroalgae are colonized by diverse microorganisms influencing the physiology of their host. However, cell-cell interactions within the surface microbiome (epimicrobiome) are largely unexplored, despite the significance of specific chemical mediators in maintaining host-microbiome homeostasis. In this study, by combining liquid chromatography coupled to mass spectrometry (LC-MS) analysis and bioassays, we demonstrated that the widely diverse fungal epimicrobiota of the brown alga can affect quorum sensing (QS), a type of cell-cell interaction, as well as bacterial biofilm formation.

Aldehyde perception induces specific molecular responses in Laminaria digitata and affects algal consumption by a specialist grazer.

In the marine environment, distance signaling based on water-borne cues occurs during interactions between macroalgae and herbivores. In the brown alga Laminaria digitata from North-Atlantic Brittany, oligoalginates elicitation or grazing was shown to induce chemical and transcriptomic regulations, as well as emission of a wide range of volatile aldehydes, but their biological roles as potential defense or warning signals in response to herbivores remain unknown. In this context, bioassays using the limpet Patella pellucida and L.

The microbiome: Effects of region, season, and physiology.

Introduction: is a canopy-forming species of brown algae and, as such, is considered an ecosystem engineer. Several populations of this alga are exploited worldwide, and a decrease in the abundance of at its southern distributional range limits has been observed. Despite its economic and ecological interest, only a few data are available on the composition of microbiota associated with and its role in algal physiologyn.

qPCR-based relative quantification of the brown algal endophyte in : variation and dynamics of host-endophyte interactions.

Morphological changes-such as dark spots, twisted stipes and deformed blades-have been observed in wild and cultivated . The putative cause for the disease symptoms is the filamentous endophytic brown alga , which is known to invade stipes and fronds of its hosts. Little is known about this interaction and its occurrence in the field, although former studies indicated high endophyte prevalence in kelp populations.