Bacterial mobile genetic elements (MGEs) are critical in disseminating pathogenesis and antimicrobial-resistance determinants. These elements, such as conjugative plasmids, Integrative and Conjugative Elements (ICEs), and Integrative and Mobilizable Elements (IMEs), typically consist of four modules in their conjugative regions: the origin-of-transfer (oriT) region, relaxase gene, type IV coupling protein (T4CP) gene, and a gene cluster encoding type IV secretion system (T4SS). The oriT region is essential for the transfer process, as it is recognized by the relaxase and undergoes nicking at a conserved site (nic), resulting in the formation of single-stranded DNA (ssDNA). This ssDNA, together with the relaxase and auxiliary proteins, forms a relaxosome and is transferred with the assistance of T4SS and its T4CPs.

The database oriTDB currently contains comprehensive information on the oriT regions, nic sites, relaxases, auxiliary proteins, relaxosomes, T4CPs, T4SSs, as well as the cargo genes in the MGEs.