- The Ton system, an ABC transporter, and a universally conserved GTPase are involved in iron utilization by Brucella melitensis 16M. Danese, I., Haine, V., Delrue, R.M., Tibor, A., Lestrate, P., Stevaux, O., Mertens, P., Paquet, J.Y., Godfroid, J., De Bolle, X., Letesson, J.J. Infect. Immun. (2004)