User:Michael Roberts/BIOL115 Myo: Difference between revisions
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'''PROXIMAL AND DISTAL HISTIDINES''': The iron atom sits either side of the side chains of two <scene name='User:Michael_Roberts/BIOL115_Myo/Heme/4'>histidine residues</scene>. | '''PROXIMAL AND DISTAL HISTIDINES''': The iron atom sits either side of the side chains of two <scene name='User:Michael_Roberts/BIOL115_Myo/Heme/4'>histidine residues</scene>. | ||
One of these (coloured cyan) is attached to the iron atom, and is known as the ''proximal'' histidine. The other (green) is called the ''distal'' histidine. | One of these (coloured cyan) is attached to the iron atom, and is known as the ''proximal'' histidine. It is also referred to as His F8, because it is the eighth residue of helix F. The other (green) is called the ''distal'' histidine, also referred to as his E7 (7th residue of helix E). | ||
Note how the iron is pulled out slightly to one side of the plane of the heam group as a result of it's co-ordination with the side chain of the proximal histidine. | Note how the iron is pulled out slightly to one side of the plane of the heam group as a result of it's co-ordination with the side chain of the proximal histidine. | ||