Iron is one of those things that life needs, it’s at the heart of many proteins such as the hemoglobin in your blood. But getting that sweet, sweet ferrous metal is not always so easy. That’s why many creatures have evolved to use special chemical compounds known as siderophores (Greek for iron carrier). Siderophores are produced within the cell and then released into the extracellular environment where they bind to iron ions, helping to solubilize them and thus transfer them into the cell. Enterobactin (pictured above) is a particularly potent siderophore that works somewhat like the claw in one of those games where you try and retrieve a stuffed animal. In this case the oxygen atoms surround and bind to the iron atom to form metal-ligand bonds.
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