Recovery of 178 metagenome-assembled genomes from sediments in subterranean estuary

Subterranean estuaries (STEs), the mixing zones between terrestrial groundwater and seawater, function as critical biogeochemical reactors that buffer anthropogenic pollutants from entering the open ocean. To date, microbial diversity and community structure within STEs remain poorly characterized. Here, we reconstructed 178 metagenome-assembled genomes (MAGs) exclusively from bacteria (no archaeal MAGs identified). All MAGs met medium-quality standards (>70% completeness, <10% contamination), including 59 near-complete (>90%), 47 with completeness over 80%, and 23 over 75% complete genomes. These MAGs spanned 17 bacterial phyla, with Pseudomonadota dominating (30.9%). Crucially, 157 MAGs (88%) are unclassified at the species level based on GTDB assessment, potentially representing novel taxa, including 1 candidate family, 28 candidate genera, and 128 candidate species. This study provides a genomic resource for studying the functional roles of these unclassified taxa in STEs.