Trans-Atlantic Fucus microbiome

Understanding the resilience of intertidal communities to climate change requires understanding the microbiomes of macrophytic algae that are key ecosystem engineers and/or major primary producers. Some, perhaps all, of these macrophytes disintegrate if deprived of their bacteria, but the particular bacteria that maintain algal multicellularity remain virtually unknown, as are host transcriptomic responses. Moreover, how macroalgal microbiomes change in space and time is poorly known. Is there a "cool, wet" versus a "hot, dry" macroalgal microbiome(s)? If so, how does this affect host function? Here, microbiomes were characterized over the vertical gradient of the intertidal zone on the Maine shore in differentially-zoned species within each of two prominent genera, Fucus ("rockweed") and Porphyra ("laver"). Contemporaneously, a trans-Atlantic study of microbiomes of the mid-zone Porphyra umbilicalis and Fucus vesiculosus will determine whether compositional changes found over an intertidal stress gradient are mirrored over the latitudinal range of mid-zoned species. Environmental variation associated with microbiome collections was measured with in situ sensors and from archival and real time data available from government climate services (e.g., NOAA).