The genome contains three replicons: a chromosome (~3.7 megabases), and two megaplasmids pSymB (~1.7 megabases), and pSymA (~1.4 megabases).
O xenoma contén tres replicóns: un cromosoma (~3.7 megabases) e dous megaplásmidos pSymB (~1.7 megabases) e pSymA (~1.4 megabases).