Metagenomic sequencing of Saccharina latissima enriched RUSITEC communities

Seaweed plays a crucial role in carbon cycling and is expected to become a key source of biomass in the future as human and livestock feed, and biofuels. While seaweed has been used historically as a feed source for livestock that graze near coastlines, how it is digested in the rumen has never been investigated. Here, we investigated if and how the brown algae Saccharina latissima is catabolized in the rumen ecosystem through in vitro (cattle-based RUSITEC systems; up to 50 percent inclusion) experiments. We determined that the ruminal decomposition of alginate, a prominent component of brown algae cell wall, requires dedicated catabolic pathways complete with alginate lyases and transport proteins.