Mediterranean Microbial Genomics and Biosynthetic Potential: Multi-source Actinomycetota BGC Catalogue — Version 1.0.0

This record is Version 1.0.0 of a living, versioned resource for Mediterranean microbial genomics and biosynthetic gene-cluster (BGC) discovery. The present release focuses on Actinomycetota and provides a reproducible catalogue of antiSMASH-derived BGC regions, source-genome metadata, GTDB-Tk taxonomy, BiG-SCAPE family information, novelty summaries, and links to the original public genome and contig accessions. The source selection contains 3,559 publicly available cultured isolate genomes associated with one of 15 Mediterranean-basin countries. The collection is multi-source and includes environmental, clinical, food-associated, animal-associated, plant-associated, and other host-associated records. No host or biome filter was applied; therefore, the dataset should not be interpreted as an unbiased ecological survey or as a prevalence estimate for Mediterranean environments. The release index contains 41,060 predicted BGC regions. The primary Actinomycetota view contains 41,038 BGCs. Three source genomes representing 22 BGCs are retained in the full catalogue but flagged as `taxonomy_anomaly` because their GTDB-Tk phylum assignment is inconsistent with their source organism name and the intended Actinomycetota scope. These records are documented separately and excluded from the primary Actinomycetota view pending marker-gene and assembly-quality review. Using BiG-SCAPE 2.0.3 at a clustering cutoff of 0.3, the original analysis identified 2,164 recurrent multi-member BGC families without MIBiG members, containing 26,332 BGC regions (64.1% of the original 41,060-region analysis). In this release, “novel” is an operational comparison to the included MIBiG reference database and clustering parameters; it does not imply experimentally confirmed chemical novelty, geographic specificity, or ecological uniqueness. The package includes the BGC-level metadata catalogue, source-category annotations, taxonomy-quality flags, family and novelty summaries, reproducibility documentation, and NCBI/ENA links for the source assemblies and contigs. Source genome assemblies are not redistributed and remain available from the public repositories through the accession links. A future version may expand the resource to additional microbial phyla and organisms while preserving the version history and concept DOI. Software and reference resources used in the analysis include antiSMASH 8.0.4, BiG-SCAPE 2.0.3, Pfam 35.0, MIBiG 4.0, GTDB-Tk 2.7.2 with GTDB release r232, InterProScan 5.77-108.0, and ESMFold