Table 1.

Mechanisms of excess iron and gallium toxicity

Mechanism	Fe	Ga
Reactive oxygen species	+	+
Disruption of transcription/translation	+	−
Damage to cell wall/membrane	+	+
Interfering with respiration	+	+
Release of cellular components	+	+
Binding to thiol groups	?	?
Change in zinc homeostasis	−	+
Disruption of iron metabolism	−	+

Mechanisms of cellular damage are listed resulting from excess iron toxicity. As these systems are common to virtually all bacteria, there is a strong potential that resistance mechanisms might be conserved across wide varieties of taxa. +, established; ?, unknown. Sources: [7, 11, 16].