A dataset for forty complete bacterial genome sequences in cultures of the toxic dinoflagellate Ostreopsis cf. ovata

Increasing occurrences of toxic dinoflagellate blooms are a growing concern under climate change. The benthic dinoflagellate <i>Ostreopsis</i> blooms through mechanisms that remain poorly understood and is assumed to produce palytoxin-like compounds such as ovatoxins. Recent studies have highlighted the diversity of bacterial communities associated with <i>Ostreopsis</i> and suggested a possible role for these bacteria in toxin biosynthesis. However, genome information on potential bacterial toxin producers remains limited. Here, we report a dataset of bacterial metagenome-assembled genomes (MAGs) obtained from the culture of the toxic dinoflagellate <i>Ostreopsis</i> cf. <i>ovata</i> strain (NIES-3351). HiFi long reads from PacBio Revio system were assembled with hifiasm-meta. We identified forty complete bacterial MAGs, each with an estimated completeness of 93-100%. These MAGs span a wide range of genome sizes (1.5 Mb to 6.7 Mb) and GC contents (36% to 67%). The dataset is available at DDBJ/ENA/GenBank under accession number PRJDB37958.