Fat Metabolism | mysite-1

Fat is used in the body for many purposes. It serves as a source of insulation, protection, vitamin absorption and energy (New Health Guide, 2017).

Before fat can be used for these purposes it has to be either broken down or synthesized. The breaking down and synthesis of fat in the body is known as fat metabolism. The process of breaking down fat is known as fat catabolism and the process of synthesizing fat is known as fat anabolism.

Fat Catabolism

Fat Anabolism

After the digestion of fats to triglycerides, by the digestive system, the triglycerides are transferred to the adipose cells by a specific kind of lipoprotein. They are stored as fat droplets. Triglycerides are broken down into fatty acid and glycerol by another lipoprotein before entering the adipose cell. Fat is moved out of the adipose cell by several chemicals to the blood stream for energy usage while glycerol is converted to dihydroxyacetone which undergoes glycolysis (Diwan, 2017).

Initiation

There are some steps that come before the oxidation of fatty acid. Altogether, they are known as initiation and they occur in the cytosol. These steps are:

First, fatty acid is converted into acyl-CoA thioester with the help of acyl-CoA synthetase (Department of Biochemistry and Molecular Biology, the University of Kansas, 1996).
Acyl-CoA is then sent into the mitochondrial membrane through a porin protein (Department of Biochemistry and Molecular Biology, the University of Kansas, 1996).
Long fatty acids are turned to carnitine with the help of carnitine acyl transferase I while short chain fatty acids enter the mitochondrial matrix (Department of Biochemistry and Molecular Biology, the University of Kansas, 1996).
Translocase catalyzes the translocation of acyl carnitine to the mitochondrial matrix (Department of Biochemistry and Molecular Biology, the University of Kansas, 1996).
Acyl carnitine is esterified to acyl-CoA. It is catalyzed by carnitine acyl transferase II (Department of Biochemistry and Molecular Biology, the University of Kansas, 1996).

Now that acyl-CoA is in the mitochondrial matrix, beta oxidation occurs.

Fat can be synthesized from other nutrients like carbohydrates. After carbohydrate is converted into acetyl-CoA, it is transferred to the cytosol for fat synthesis.

Steps:

Biotin, an enzyme prosthetic group, is carboxylized by acetyl-CoA carboxylase with the use of ATP. The carboxyl group is then passed on to acetyl-CoA to produce malonyl-CoA.

Learn more

(1.bp.blogspot.com, 2017)

Questions

Fat metabolism is the process of making and breaking down fats in the body.
Fat catabolism is the process of breaking fats down in the body.
Fat anabolism is the process of synthesizing fats by the body.
The initiation process includes the conversion of fatty acid to acyl-CoA for oxidation.
The initiation step ends with the formation of acyl-CoA in the mitochondrial matrix.

Answers

What is fat metabolism?
What is fat catabolism?
What is fat anabolism?
What does the initiation step include?
How does the initiation step end?