Rickettsia are obligate intracellular bacteria normally living in arthropod cells. They occationally cause diseases in human. R. conorii is the agent of Mediterranean spotted fever, which is transmitted by ticks.

To understand their pathogenicity, physiologies, and evolutionary mechanisms, the 1.27 Mb genomic sequence of R. conorii has been determined. Its comparison against the previously sequenced R. prowazekii has revealed many surprising biological features of Rickettsia.

RicBase aims to organize the genomic and updated annotation data to assist followup studies of those bacteria.