Fig. 7: Strategies adopted by Salmonella to prevent iron-driven bactericidal mechanisms.

a S. Typhimurium overexpress different iron acquisition systems to compete for the intracellular iron (1). Excess of iron can be used by the host to generate antimicrobial mechanisms which improve bacterial clearance (2). b Non-typhoidal Salmonella limit intracellular iron loading by reducing surface expression of TFRC most likely through the action of MARCH1 (1 and 2). c Infection with S. Typhi results in increased iron loading and activation of oxidative and nitrosative stress mechanisms (1–4). However, the higher production of detoxifying enzymes, such as HmpA (5), protect the bacteria by the toxic effect of RNI. Enterobactin (entF and entC) are responsible of iron acquisition during stress (5).