The Structure of Cyclooxygenase-1 with Bound Arachidonic Acid
See the structure of aspirin
See the amino acid structure of Cox-1
Cyclooxygenase-1
CPK Color Scheme
C
O
N
Co
3+
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.
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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
Cobalt
3+
ion in the center
.
Zoom Out and examine it yourself
.
Locate
Serine #530
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.