Resequencing of the oral bacterium Actinomyces oris MG-1 for high-quality genome assembly

Actinomyces oris is an important early colonizer in the oral cavity and plays a critical role in dental plaque formation. A hallmark of A. oris is the presence of three distinct types of fimbriae on its cell surface, which facilitate adhesion to salivary proteins and various oral streptococci. Interestingly, A. oris also exhibits physical interaction with Fusobacterium nucleatum, a key bridging species and oral pathobiont. This interaction appears to be independent of the well-characterized fimbrial structures, suggesting a novel mechanism of interspecies association.To elucidate the molecular basis of A. oris/F. nucleatum coaggregation, we are generating a library of A. oris random transposon mutants using a Tn5 mutagenesis system. Each mutant will be subjected to coaggregation assays with F. nucleatum to identify surface factors required for the interaction.The existing genome assembly of A. oris MG-1 (PRJNA327886) consists of 485 contigs, which limits the resolution of mutant mapping and analysis. To overcome this, we resequenced the MG-1 genome using both Illumina short-read and Oxford Nanopore long-read technologies, resulting in a high-quality, complete genome assembly. This dataset will support downstream functional genomics and interaction studies between A. oris and F. nucleatum.