The Blueremediomics-cocultures project : A multi-omics analysis of Prymnesium parvum holobiont reveals nutrient stress-driven interactions with a synthetic bacterial community.

Microalgal-bacterial interactions are central to nutrient cycling and ecosystem functioning, yet the mechanisms structuring these associations within marine microbiomes under defined nutrient constraints remain poorly resolved. We investigated how biotic interactions within the holobiont of the microalgae Prymnesium parvum shape responses to nutrient limitations. This harmful alga was co-cultivated with a synthetic 15-member bacterial community (SynCom) under controlled nitrogen (N), phosphorus (P), and vitamin B12 limitation. To enable strain-resolved analyses of community activity, whole-genome sequencing was performed for each SynCom member prior to the co-culture experiments. These genome assemblies provided high-quality reference sequences for downstream mapping of metatranscriptomic reads. During the co-cultures experiment, DNA and RNA were collected to characterize microbial community composition and functional activity. The dataset includes 16S rRNA gene metabarcoding data and metatranscriptomic sequencing data generated from algal-bacterial co-cultures across nutrient regimes. These data provide a resource to explore microbial interactions, nutrient-dependent community dynamics, and transcriptional responses within algal holobiont under controlled laboratory conditions.