Fatty Acid Synthesis

Why is fatty acid synthesis important?

It provides essential molecules for energy storage, cell membranes, hormones, messengers, co-factors, pigments, and detergents.

What is the primary molecule required for fatty acid synthesis?

Malonyl-CoA (not just acetyl-CoA).

Which enzyme catalyzes fatty acid synthesis?

Fatty acid synthase (a polypeptide homodimer with 7 active sites).

What are the four repeating steps in fatty acid synthesis?

• Condensation

• Reduction

• Dehydration

• Reduction

How does the fatty acid chain grow during synthesis?

By 2-carbon units added via malonyl-CoA in each cycle.

What happens after one round of synthesis?

The process repeats until the desired fatty acid chain length is reached (e.g., palmitate, 16:0).

Where in the cell does fatty acid synthesis occur?

In the cytoplasm.

What is acetyl-CoA's role in fatty acid synthesis?

It is the central molecule, but must first be converted into malonyl-CoA via acetyl-CoA carboxylase.

How is fatty acid synthesis regulated?

• Through acetyl-CoA carboxylase (rate-limiting step)

• Allosteric and hormonal regulation (e.g., insulin activates)

• Compartmentalization in the cytosol