Iron is vital to most bacteria, but in high quantities can be toxic. Bacteria can achieve iron homeostasis even in environments with low quantities of this element. In this situation, some bacteria use specialized proteins, which maximize the absorption of iron. Pathogenic bacteria living in the human blood can maintain their iron homeostasis by using the host's haemoglobin or other iron-complexes. Bacteria also have proteins, such as ferritine, which they used to store iron as an intracellular reserve. When in environments with toxic levels of iron, bacteria use their iron detoxification proteins (Dps), which protect their chromosome from damage.
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