|
11. Squalene epoxide is then converted to lanosterol by lanosterol synthase. |
|
Biosynthesis of Cholesterol: |




|
CoA |
|
O |
|
O |
|
S |
|
H2O |
|
CoA |
|
CoA |
|
O |
|
S |
|
+ |
|
Acetyl-CoA |
|
Acetoacetyl-CoA |
|
1. Condensation of Acetyl-CoA and Acetoacetyl-CoA, catalyzed by HMG-CoA synthase, forms HMG-CoA (3-hydroxy-3-methylglutaryl-CoA). |
|
1. |

|
5. 5-pyrophosphomevalonate to 3-isopentenyl pyrophosphate (IPP) by mevalonate-5-pyrophosphate decarboxylase. |

|
7. Catalyzed by prenyl transferase (farnesyl pyrophosphate synthase) dimethylallyl pyrophosphate undergoes reaction with 3-isopentenyl pyrophosphate to form geranyl pyrophosphate. |
|
8. Catalyzed by prenyl transferase (farnesyl pyrophosphate synthase) dimethylallyl pyrophosphate undergoes reaction with 3-isopentenyl pyrophosphate to form geranyl pyrophosphate. |
|
6. Isopentenyl pyrophosphate isomerase catalyzes isomerization of IPP to dimethylallyl pyrophosphate. |

|
9. 3-isopentenyl pyrophosphate reacts with geranyl pyrophosphate forming farnesyl pyrophosphate. (This reaction is also catalyzed by prenyl transferase.) |
|
10. Two molecules of farnesyl pyrophosphate condense to form squalene using squalene synthase. |

