Stage 1 - acetyl-CoA Production - Beta Oxidation Flashcards
Where does beta oxidation take place?
Mitochondria
How many C atoms are produced at a time in beta oxidation/how many are removed at a time?
2
What is the difference between synthase and synthetase?
synthetase = ATP
synthase = no ATP (They catalyze reactions where two small molecules are combined to form a larger molecule)
How are fatty acids prepared? Where does it occur?
By activating them to acyl-CoA (acyl CoA synthase occurs in mitochondria)
How are fatty acids activated? What does it result iin?
The nucleophilic O2 of the fatty acid attacks the alpha P of ATP which is the electrophile.
Fatty acyl CoA thioester
What transports fatty acids into the mitochondria?
Acyl-carnitine transporter
Beta oxidation - Step 1
What is the cofactor?
What is the enzyme?
Oxidation by FAD on acyl CoA between a and B carbons creating a double bond (alkane->alkene)
FAD->FADH2
Acyl CoA dehydrogenase
Beta oxidation - Step 2
What gets inputted?
What is the enzyme?
Hydration on the double bond beta carbon (alkene->alcohol)
Water
Enol CoA hydratase
Beta oxidation - Step 3
What is the cofactor?
What is the enzyme?
Oxidation by NAD+ at the alcohol
NAD+->NADH + H+
B-hydroxylacyl-CoA dehydrogenase
Beta oxidation - Step 4
What gets inputted?
What is the enzyme?
What is made?
Lysing of the a and B carbon
H+ and CoASH
Thiolase
Acetyl-CoA (into CAC)
How many acetyl-CoA are produced? How many passes through the B-oxidation sequence? How many FADH2 and NADH are produced
Fatty acid = (Number of C)/2
Above number - 1
Above number -1
What does activation and transport of fatty acids from the cytoplasm to the mitochondrial matrix require?
ATP, carnitine, and coenzyme A.
When NAD+ goes from NAD+ to NADH what does it accept?
Hydride ion
What is true regarding the “dehydrogenase” family of enzymes?
They commonly involve the cofactors NAD+/NADH or FAD/FADH2
They catalyze oxidation-reduction reactions
