By investigating how phytoplankton-produced glycans influence microbiome assembly, this project directly addresses how glycan production contributes to carbon sequestration in the ocean. It investigates the hypothesis, that these glycan structures provide a protective zone against antagonistic bacterial colonizers, while simultaneously providing a home to selected phycosphere bacteria. Via experimental and computational analyses, A6 HOME will elucidate the genomic basis of phytoplankton glycan production that shape phycosphere microbiomes.