The Structure of Cyclooxygenase-1 with Bound Arachidonic Acid
See the structure of aspirin
See the amino acid structure of Cox-1
CPK Color Scheme
This is the human cyclooxygenase-1 protein (Cox-1). Cox-1 is colored to show alpha helices in red ribbons, and beta-pleated sheets in yellow ribbons.
to reset the view of Cox-1.
If you zoom in some,
you will see arachidonic acid (gray structure surrounded with dots made of mostly carbon and hydrogen) that is bound inside the active site of Cox-1. The two red atoms on arachidonic acid are oxygen.
Notice the protoporphyrin IX ring with
ion in the center
Zoom Out and examine it yourself
that is acetylated by aspirin.
Aspirin adds an acetyl group to Serine 530 which as you can see is very near the arachidonic acid. Acetylation of Cox-1 (or Cox-2) irreversibly inactivates the enzyme. That's how aspirin works.