**3.5 Interaction with iron metabolism**

Antunes et al. have demonstrated that virulent bacteria are able to acquire iron in the blood and tissues [33]. Given the essential role of iron in bacterial physiology and pathogenicity, iron uptake and metabolism have become attractive targets for the development of new antibacterial agents [52, 53]. The ion gallium [Ga(III)], a ferric iron [Fe(III)] mimetic, has been shown to inhibit the growth of many bacterial species by interfering with iron-dependent metabolic pathways. Therefore, gallium drugs have gained special interest in the fight of MDR-GNB infections [31]. Gallium nitrate is an anticancer drug that was approved by the FDA for the treatment of cancer-associated hypercalcemia. Antibacterial properties of gallium nitrate have been previously reported against GNB infections, both *in vitro* and *in vivo* [31–35]. In addition, Ebselen as mentioned before has the characteristic to inhibit TonB in *A. baumannii* and *E. coli* [51].
