FA II

Question 1

FA are made in the cytosol. If they need to be longer, we send them to the _____ or ____.

Answer 1

1. SEr

2. Mitochondria

Question 2

In the blood, _____ must be tagged with albumin to keep them from clumping.

Answer 2

LCFA must be tagged with albumin to keep them from clumping.

Question 3

There are 2 steps to FA degradation

Answer 3

1. FA movement inside the MT

2. B Oxidation

Question 4

_____ and ____ can diffuse into the mitochondria. However, the outer MT membrane is impermeable to _____.

Answer 4

short chain FA and medium chain FA can diffuse into the membrane. However, the outer MT is not permeable to LCFA and VLCFA.

Question 5

How do we combat the fact that LCFA are not permeable to the outer mitochondrial membrane?

Answer 5

ADD A ACYL COA

Question 6

Step 1 Steps

Answer 6

As we have said, the outer membrane is not permeable to LCFA.

So:
1. FA–[Fatty acyl CoA synthetase]–> Fatty Acyl CoA
Fatty Acyl CoA can now cross the membrane into the intermembrane space. But now, there is a problem, it cannot cross the inner mT membrane

This required 1 ATP

2. So we want to remove the Co-A and add a carnitine. Adding a carnitine is its right of passage into the matrix.
   Fatty Acyl CoA–[CPT-1: carnitine palmitoytransferase I]–> Fatty Acyl Carntine.

CPT-1 is the rate limiting enzyme in FA breakdown.

3. Fatty acyl carnitine can now move into the matrix via CACT (carnitine shuttle)
   Carnitine shuttle is an antiport. It moves Fatty acyl carnitine into the matrix and moves carnitine out
4. Fatty acyl carntine is now acted upon by CPTII to remove the carnitine and change it back to Fatty acyl coA

Question 7

Shortcut of phase 1

Answer 7

To get past outer MT membrane:
1. add a coA
To get past the inner MT membrane
2. add a carnitine
Once inside
3. remove carnitine and add a coA again.

Question 8

Where is fatty acyl coA synthetase located?

Answer 8

on the outer membrane

Question 9

What is CPT-1

Answer 9

Carnitine palmitoytransferase will remove the coA and add a carnitine. Located in the inter mT membrane

Question 10

What is CACT

Answer 10

CACT is the carnitine shuttle that will transport fatty acyl carnitine to the mitochondrial membrane.

It is an antiport and remove the build up of carnitine from inside the matrix

Question 11

What is CPT-II

Answer 11

Removes carnitine and adds coA

Question 12

Where is CPT-1 located

Answer 12

intermembrane space

Question 13

Where is CACT located

Answer 13

inner mt membrane

Question 14

where is CPT-II located

Answer 14

inner mt membrane

Question 15

What is the rate limiting enzyme in FA breakdown?

Answer 15

CPT-1

Carnitine palmitoy transferase!

Question 16

Our typical saturated FA have how many carbons

Answer 16

an even number

16-20

Question 17

What do we make in B oxidation?

Answer 17

1. Acetyl Co-A- taken into the TCA cycle
2. NADH–> move electrons to complex 1
3. FADH2–> move electrons of coQ

Question 18

B oxidation makes 3 things: what is it?

Answer 18

1. Acetyl CoA
   NADH
   FADH2

Question 19

What is the first substrate of B-oxidation?

Answer 19

Fatty Acyl Co-A

Question 20

Acroynm for B oxidation

Answer 20

OHOT
oxidation
hydration
oxidation
thiolysis

Question 21

Oxidation

Answer 21

ACAD (acyl coA dehydrogenase) will oxidize Fatty acyl coA

FADH2 is made

Question 22

Why is ACAD important

Answer 22

it causes many disease

Question 23

Hydration

Answer 23

NADH is made

Question 24

2nd oxidation step

Answer 24

Acetyl CoA is released

Question 25

The only enzyme to remember in B oxidation is

Answer 25

ACAD Acyl Co-A Dehydrogenase

Question 26

B oxidation occurs where?

Answer 26

mT matrix

Question 27

Types of ACADS

Answer 27

4 types 1. SCAD 2. MCAD 3. LCAD 4. VLCAD

Question 28

______ is the type of ACAD that causes the most diseases

Answer 28

MCAD medium chain acyl coA dehydrogenase

Question 29

What happens if we have a FA with a odd number of carbons?

Answer 29

Phase 1- same. However, if we break it down, we will be left with a 3 carbon compound known as PROPIONYL COA. So what do we do? PROPIONYL COA.--[propionyl coA carboxylase]--> methylmelonyl coA (a 4 carbon compound) methyl melonyl coA will eventually become succinyl coA and go into the TCA cycle

Question 30

3 carbon compound created when oxidizing odd numbered FA

Answer 30

propionyl coA

Question 31

What would we do to proponiol coA

Answer 31

carboxylate it via propionyl coA and make a 4 carbon compound called methmalonyl coA

Question 32

What happens to the methyl-melonyl coA made?

Answer 32

it will eventually become succinyl coA and enter the TCA cycle

Question 33

What happens if we are trying to break down unsaturated FA?

Answer 33

We will need new enzymes. We metabolize it until a DB is reached 1. Reducatases will reduce the DB 2. Isomerase will move the disrupted bond so it can be degraded by a regular enzyme

Question 34

How are VLCFA--> LCFA

Answer 34

perixisomal B oxidation | once you get to 20 carbons, it undergoes normal oxidation

Question 35

When you are undergoing B oxidation in the perixoisome, do you make energy?

Answer 35

NO. You do not make any NRG. High energy electrons are transferred to O2 to make H202.

Question 36

If you undergo B oxidation in the perixisome, wont it create a build up of H2O2?

Answer 36

No. A catalase will then convert the H2O2 to water and O2.

Question 37

Key difference in peroxisomal B oxidation and regular?

Answer 37

During the 1st oxidation stage, ACAD is not used. | It will use Acyl CoA Oxidase, which still creates FADH2, but not for NRG. electrons are transferred to O2 to make H2O2

Question 38

What enzyme is used instead of ACAD in perixosomal B oxidation?

Answer 38

Acyl CoA Oxidase

Question 39

Zellweger syndrome

Answer 39

patient has a defect in the generation of peroxisomes. Thus, they cannot break down VLCFAs

Question 40

MCAD deficiency

Answer 40

People with MCAD deficiencies cannot break down medium chain FA. It leads to a secondary deficiency in carnitines because we rare excreting a lot of it out. We are soaking up alot of our carnitines. Person will have elevated levels of ammonia Pts will depend on glucose for NRG. This is preventative

Question 41

Ketone bodies are made when we have a lot of _______

Answer 41

acetyl coA

Question 42

What begins the creation of ketone bodies?

Answer 42

Ketone bodies are made when we have a problem with insulin signaling (people with DB or on a ketogenic diet). Glucose is not getting into the cells; so we cannot use it for energy. As a result, we start to use our fat stores. Fat is broken down and is made into acetyl coA We then get a build up of acetyl coA, which will then make ketone bodies.

Question 43

Where are ketone bodies made/

Answer 43

ONLY the mT matrix of the LIVER!!!!

Question 44

Characteristics of ketone bodies

Answer 44

1. acidic | 2. water-soluble

Question 45

3 types of ketone bodies

Answer 45

1. acetoacetate 2. acetone 3. beta- hydroxybutryate.

Question 46

What can use ketone bodies?

Answer 46

1. brain 2. muscles 3. kidneys

Question 47

Can RBCs use ketone bodies?

Answer 47

NO!

Question 48

How can we create acetoacetate?

Answer 48

2 acetyl coAs combine--> acetoacetyl CoA--> | HMB CoA--> Acetoacetate

Question 49

few hours after fasting

Answer 49

1. blood glucose 2. glycogen stores 3. gluconeogenesis

Question 50

1 day after not eating

Answer 50

B oxidation of TAGS

Question 51

3 days after eating

Answer 51

1. begin to make ketone bodies 2. proteins in muscles break down 3. glycerol from TAGS and proteins enter glucogonic AA enter gluconeogenesis can provide NRG to the brain and RBC

Question 52

1-2 weeks after

Answer 52

brain will use ketone bodies

Question 53

2-3 months

Answer 53

death

Question 54

When can we get physiological ketosis?

Answer 54

slight elevation of ketone bodies occurs when fasting, pregnant, excercising, babies and ketogenic diet

Question 55

Pathological ketoacidosis

Answer 55

Glucagon/insulin ratio is increased and we favor FA breakdown

Question 56

in diabetic ketoacidosis

Answer 56

ketones are being formed and they drop your blood pH big time

Question 57

What does CACT stand for

Answer 57

Carnitine acylcarnitine translocate (CACT) shuttles fatty acyl carnitine into the matrix

Question 58

why do we die from ketone bodies

Answer 58

blood pH drop