Virtuelle (Nano) Welten PDB Molecule of the Month 81: Cytochrome p450

Exploring the Structure

The best-studied cytochrome p450 enzyme is a bacterial enzyme that adds oxygen to camphor. Two early structures are shown here. On the left (PDB entry 3cpp) is a structure with camphor and carbon monoxide bound in the active site. The carbon monoxide is an inhibitor that poisons the enzyme. It binds to the iron (large yellowish sphere in the middle of the heme) in the same place as oxygen gas. The cysteine amino acid at the bottom activates the iron. The structure on the right (PDB entry 1noo) shows camphor after the reaction, when an oxygen atom has been added (the other oxygen atom is released during the reaction as a water molecule). Looking through the PDB, you can find dozens of other structures of cytochrome p450cam, showing many different molecules bound in the small active site, and showing many different stages in the reaction.

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A list of 'cytochrome p450' related entries in the PDB as determined by a keyword search on October 1, 2006 is available. For more information on cytochrome p450, click here.