Biochem Lecture 19- Fatty Acid Catabolism

Triacylglycerols

about 1/3 of our energy needs are met by these dietary molecules, and many hibernating animals rely on these exclusively for their energy during hibernation

Long-term energy

lipids are really great for _______ _____________ ______________ as opposed to glucose and glycogen

Get fat to cell, get fatty acids into mitochondria, let burnination begin

these are the 3 stages of releasing the fountain of fat energy

Bile salts

these emulsify dietary fats in the small intestine, morming mixed micelle, first part of transporting fatty acids into the bloodstream

Intestinal lipases

after bile emulsifies the dietary fats, these degrade the triacylglycerols

Chylomicron

these are lipid transporters where triacylglyerols are incorporated with cholesterol and apolipoproteins, which are able to then move through the lymphatic system into the bloodstream and tissues

Lipoprotein Lipase

this enzyme is super interesting and converts triacylglyerols into fatty acids and monoacylglyerols

Gs (beta adrenergic receptor)

which type of GPCR trigger the mobilization of stored triacylglyerols?

PKA

this activated phosphorylator is what the Beta adrenergic receptor eventually activates to help mobilize the fatty acids stored for energy

Hormone sensitive lipase, perilipins

PKA phosphorylates these two things when activated to release stored fats

Perilipins

these, when phosphorylated, release CGI-58 and activates ATGL

Adipose Triacylglyerol Lipase (ATGL)

this is activated by CGI-58, and converts triacylglyerol to diacylglyerol (releasing 1 fatty acid)

Hormone Sensitive Lipase (HSL)

this, when phosphorylated, gains access to the lipid droplet and converts the diacylglycerol to monacylglyerol (releasing the 2nd fatty acid)

monoacylglyerol lipase

this releases the last fatty acid after HSL and ATGL have taken off the other two

Serum Albumin

fatty acids bind to this in the bloodstream, where it binds to up to 10 fatty acids

Magic (lol we just don't know yet)

fatty acids enter the bloodstream through what mechanism?

Fatty acid transporter

these trasnport fatty acis from the bloodstream into the tissue cells that need energy

Glycerol Kinase

this enzyme breaks down glycerol while using ATP, which can then enter glycolysis as G3P

Acyl-CoA

this is what fatty acids need to be converted into in order to be metabolised

ATP

in order to transform into AcyL CoA, the fatty acid reacts with this in order to form Acyl CoA

Carnitine

this is what reacts with Acyl CoA in the cytosol in order to be transported across the inner membrane of the mitochnodria to the matrix, then transferred back after Acyl-Carnitine reacts with CoA in the matrix

Oxidation, Hydration, Oxidation, Thiolysis

these are the 4 steps of fatty acid oxidation

Beta carbon

this carbon is the most important carbon in fatty acid oxidation

Trans double bond, FAD, FADH2

In the first step of Beta oxidation, there is a _________(what kind of bond?) formed between the alpha and beta carbons of the Acyl-CoA, reducing a molecule of ______ to ____________ in the process

Water, alcohol (OH), Beta

In the second step of Beta oxidation, ________(what molecule?) reacts to get rid of the double bond and to put an _____________(what kind of functional group?) on the ______(alpha/beta) carbon

Carbonyl, NAD+, NADH

In the third step of beta oxidation, the alcohol gets oxidized to a _____________(what functional group?), which reduces a molecule of _________ to __________ in the process

CoA-SH, 2, Acetyl-CoA

In the 4th step of beta oxidation, the Beta carbon becomes electrophilic and it reacts with ___________, to lose ___(how many carbons?) from the fatty acid chain in the form of __________-_______, and the rest of the fatty acid remains, which can undergo beta oxidation until no carbons are left

O HOT

this is the way you will remember beta oxidation for the rest of your life

8 Acetyl CoA, 7 FADH2, 7 NADH

For palmitic acid (C16), how many acetyl CoA are made, how many FADH2, and how many NADH are made?

Odd, Alpha, Beta

for the oxidation of unsaturated fatty acids with the double bond on the _______(odd/even) carbon, the beta oxidation will proceed normally until it reaches the cis double bond, which then isomerases the double bond to the ________ and _____ carbons, which proceeds normal

1 Less FADH2

in the oxidation of the monounsaturated fatty acids with the double bond on the odd numbered carbon, it produces the same amount of energy, except for it produces ____ ______ __________

Even, NADPH

For the oxidation of the unsaturated fats on the _______ carbon, it works the same, except during isomerization it uses 1 molecule of ____________ in the process

Ketone bodies

these are generated when oxaloacetate is depleted and Acetyl CoA can't enter the CAC, so there is no free CoA

Gluconeogenesis

oxaloacetate is depleted in the liver when ketone bodies form because the oxaloacetate is siphoned from the CAC for this process under starvation conditions

Acetoacetate

the formation of Ketone bodies from the 2 acetyl Coas, regenerates CoA in the liver, but produces this, which can be converted into Acetone and D-Beta-Hydroxybutyrate

Beta-Hydroxybutyrate

this ketone body gets transported out of the liver into the tissues that need energy where it can then be regenerated into 2 acetyl-CoA molecules, where it can enter the CAC

Liver

even though 2 Acetyl_CoA molecules get regenerated from the ketone body, it is still useful the human body because the oxaloacetate is not being siphoned into gluconeogenesis, because the 2 acetyl-CoA are transported to tissue that is not the __________

Diabetes

production of ketone bodies can become extremely high in untreated ____________ (and starvation)

Acetone

this can be produced in ketone body utilization, and is super toxic and has a characteristic odor

Acidosis

ketone bodies can produce high levels of acetoacetate and B-hydroxybutyrate, which lower the blood pH dangerously, which is called this