Lipid Metabolism: FA Degradation Flashcards Preview

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Flashcards in Lipid Metabolism: FA Degradation Deck (10)

Which FAs can easily pass through the mitochondria and which ones can't? What is the protocol for the FAs that cannot pass?

SCFAs + MCFAs can pass through

LCFAs can't ; Protocol--> go to peroxisomes to be broken down into degradable form--> sent to mitochondria for continued Beta-Oxidation


What is the general step for FA oxidation?

1.) FA needs to be broken down by lipases
2.) FA needs to enter the mitochondria via rate-limiting step of Fatty Acyl-CoA Synthetase
3.) **Carnitine Acyl Transferase I/ Carnitine Palmitoyl Transferase I will change the CoA--> Carnitine so it can get in through to matrix
4.) Carnitine Acyl Translocase I will push into the Matrix
5.) Carnitine Palmitoyl Transferase II/ Carnitine Palmitoyl Transferase II will change the Carnitine--> CoA
6.) Carnitine will go through the Carnitine Acyl Translocase I back to the intermembrane space


Once the FA chain is in the matrix, what are the general steps for the breakdown of one unit of Acetyl CoA?

1.) Oxidation
2.) Hydration
3.) Oxidation
4.) Thiolysis


What is the net breakdown of 1 Acetyl CoA release?

1 Acetyl CoA
1 NADH--> ETC Complex I
1 FADH2 --> ETC Complex II (CoQ/Ubiquinone)


What are the different types of Acyl-CoA dehydrogenase and what does it do?

It catalyzes the first oxidation of the Beta Oxidation in the matrix (Acyl-CoA Dehydrogenase):

Different Types:


What happens during odd-chain oxidation in the mitochondria?

The resulting molecule that becomes produced is Propional-CoA (3-C):

Propionyl-CoA Carboxylase-->
Carboxylates Proionyl CoA (3C)--> Methylmalonyl-CoA (4C)

***A MethylMalonyl-CoA Mutase converts:
Methylmalonyl-CoA--> Succinyl CoA

*Succinyl CoA then falls into the TCA cycle


What is the process for unsaturated FAs for degradation?

Reductase followed by Isomerase to get it to Saturated State!


What happens when their is defect in MCAD?

Their is a halt in Beta Oxidation which results in the sole use of Glycogen via glucose release


What happens when the body starves?

Ketone body from conversion of Acetyl CoA:
1.) Acetoacetate (23 ATP) (24 -1= 23 for synthesis)
2.) Hydroxybutyrate (26 ATP)
3.) Acetyl CoA (24 ATP)


What is the bodies process through which the metabolism goes through when the human is not feeding?

1.) glycogenolysis (few hrs)
2.) gluconeogenesis (few hrs)
3.) FA catabolism (Day 1)
4.) Ketone Body Production + FA catabolism (Day 3)
5.) Ketone Bodies only (1-2 weeks)