B Oxidation of Fats Flashcards
In what organs does B-oxidation of fats occur?
Liver + Muscle
pathway of B-oxidation of fats
Acyl CoA -(Acyl CoA dehydrogenase + FAD)-> Enoyl CoA -(Enoyl CoA hydratase + H2O)-> Hydroxyacyl CoA -(Hydroxyacyl CoA dehydrogenase + NAD)-> B-Ketoacyl-CoA -(Thiolase + CoA)-> Fatty Acyl CoA + Acetyl CoA –> Ketogenesis = Ketones; OR Kreb’s 12ATP
Where does B-oxidation of fats occur within the cell?
mitochondrial matrix
(for majority of FAs)
An FA made of 2-4 Carbons is termed
Short chain
An FA made of 6-14 Carbons is termed
Medium chain
An FA made of 16-20 Carbons is termed
Long chain
what FA do we make when we make TAGs for storage?
Long chain
An FA made of 22 or more Carbons is termed
Very Long chain
Which FAs are located in the Mitochondria?
Short, Medium, and Long chain FAs
Which FAs are located in the Peroxisomes?
Very Long chain FAs
How are Short chain FAs transported?
Simple diffusion
How are Medium chain FAs transported?
Diffusion
How are Long chain FAs transported?
Carnitine cycle
How are Very Long chain FAs transported?
unknown
name the 16 Carbon FA
Palmitate
Palmitic acid
name the 18 Carbon FA
Stearate
Steric acid
name the 20 Carbon FA
Arachidate
Arachidic acid
B-oxidation of fats in the Liver is also known as ____
Ketogenesis
what enzyme releases FAs from adipose tissue?
Hormone-sensitive Lipase
what 2 hormones allosterically activate Hormone-sensitive Lipase?
Glucagon + Epinephrine
Hormone-sensitive lipase converts TAGs to ____
3FAs + Glycerol
where does the glycerol from TAGs go
back to Liver
what is the function of Albumin?
transport FAs back to Liver/Muscle
What hormone is required for normal rate of B-oxidation?
T3
Where is T3 produced?
Thyroid (T4 + T3)
Liver (T4 converted to T3)
What is the coenzyme for T3?
Bile
What enzyme converts FA –> fatty acyl CoA
Thiokinase
where is the enzyme Thiokinase located?
outer mitochondrial membrane
What is the location + purpose of CPT1?
in the outer mitochondrial membrane, CPT1 puts Fatty Acyl CoA in carnitine
what is the biochemical composition of Carnitine
Trimethyl-lysine (needs B6)
(made from Lysine + SAMe)
how is Carnitine recycled, and where is the enzyme located?
CPT2 + Acyl Carnitine Translocase, in the inner mitochondrial membrane
How many ATPs are generated from B-Oxidation of Palmitic Acid?
131 ATP
How many ATPs are generated from B-Oxidation of Stearic Acid?
148 ATP
How many ATPs are generated from B-Oxidation of Arachidic Acid?
165 ATP
(Ketogenesis) Name the 3 ketone bodies
Acetoacetate (4C), B-Hydroxybutyrate (4C), Acetone (3C)
(Ketogenesis) which ketone body is found in blood/urine?
B-hydroxybutyrate
(Ketogenesis) what tissues can use ketone bodies for energy?
Heart, Skeletal muscle, + Brain only during starvation
Metabolism of ketone bodies requires what Kreb’s cycle intermediate?
Succinyl-CoA
What AAs enter the Kreb’s cycle as Succinyl-CoA?
Valine, Isoleucine, Methionine
Name the 4 coenzymes of the B-oxidation of Fats pathway? (1st –> 4th step)
FAD, H2O, NAD+, CoA
what is the enzyme in the 1st step of B-oxidation
acyl CoA dehydrogenase
what is the enzyme in the 2nd step of B-oxidation
enoyl CoA hydratase
what is the enzyme in the 3rd step of B-oxidation
hydroxyacyl CoA dehydrogenase
what is the enzyme in the 4th step of B-oxidation
thiolase
Which enzyme adds H2O to the molecule during B-Oxidation of FAs?
Enoyl CoA hydratase
The carnitine shuttle requires the enzyme CPT-1 located in the ____ and ____ is the biochemical composition of carnitine.
outer mitochondrial membrane; trimethyl lysine
FAs are stored as ____ in adipose tissue
Triacylglycerols (TAGs)
What is the energy from B-oxidation of fats used for?
glycogenesis
