Furci Flashcards
In Carnatine Shuttle, Fatty acyl-CoA is too _____ and _____ to penetrate the _____ membrane
Large
Polar
Inner
In Carnatine Shuttle, FA is transferred from CoA to ______ by _________ in the _______ membrane
Carnatine
Carnatine palmitoyl transferase I (CPT-I)
Outer
In carnatine shuttle, _______ translocase in inner membrane transfers free ______ and __________ in opposite directions
Antiport
Carnatine
Acyl-carnitine
In carnatine shuttle, ______ regenerates fatty ________, releasing carnatine
CPT-II
Acyl-CoA
Where does B-oxidation of fatty acids occur?
In the mitochondria
In B-Oxidation, carbons are released ____ at a time from the ______ end
2
Carboxyl
During B-oxidation of Saturated EVEN chain fatty acids, produces ________ and ______ and _______
Acetyl-CoA
FADH2
NADH
Where do the products of B-oxidation of EVEN chain fatty acids go?
Acetyl-CoA goes to the TCA cycle
FADH2 and NADH go to the ETC
What are the 4 steps of B-oxidation of saturated EVEN chain fatty acids
- Dehydrogenation
- Hydration (reduction)
- Dehydrogenation
- Carbon-Carbon clevage
What is the function of the family of enzymes known as Fatty Acid Dehydrogenase?
Chain-length specificity for short, medium, and long chain fatty acids
What types of FA undergo B-oxidation in the peroxisomes?
Long, very long, and branched chain FAs
What is the name of the family enzyme that allows for B-oxidation in peroxisomes?
Peroxisomal Enzymes
Peroxisomal enzymes cannot oxidize what types of FAs
Short-chain
The reduced nucleotide, ______, that is produced during B-oxidation in peroxisomes, is oxidized by molecular oxygen to produce ________.
FADH2
H2O2
Describe the geometry changes which occur during B-oxidation of UNsaturated even chain FAs
Double bonds have CIS geometry that must be changed to TRANS geometry
B-oxidation of Saturated ODD chain FAs is just like that of EVEN chained FAs except for what?
Acetyl-CoA AND PROPINOYL-CoA (by last thiolase reaction) are BOTH released
For oxidation of Branched chain FAs, the B-carbon is at the ______ point and cannot be oxidized to a ______
Branch
Ketone
During oxidation of Branched Chain FAs, they must ungergo ____-oxidation to ____ _____ releasing _______
alpha
pristanic acid
CO2
Following the release of CO2 during a-oxidation of Branch Chain FAs, the is a subsequent _______ release of _______ and ________
Alternating
Acetyl-CoA
Propinyl-CoA
Ketogenesis is the generation of _____ ______ from ________
Ketone bodies
Acetyl-CoA
During Ketogenesis, there is a _______ in blood plasma during times of _______ and _________
Increase
Fasting
Starvation
Ketogenesis releases free _____ for _________
CoA
B-oxidation
In ketogenesis, there is the bothe the synthesis, as well as the decomposition of _________
Hydroxymethylglutaryl (HMG)-CoA
During Ketogenesis, what three products are made?
Acetoacetate
B-Hydroxybutyrate
Acetone
What is another name for Lipogenesis
Fatty Acid Synthesis
What are the 2 sources of Fatty Acids
Diet
De novo synthesis (lipogenesis)
When is Lipogenesis (FA synthesis) active?
During times of excess energy intake (eg carbohydrates)
FA synthesis is linked to Glucose Metabolism through what?
Pentose Phosphate Pathway
During lipogenesis (FA synthesis), carbohydrates are converted to ______ _____ in the _____, and are stored as ______ in the _____ ______
Fatty acids
Liver
Triglycerides
Adipose Tissue
_____ (NOT _____ _______) is the main lipogenic organ
Liver
Adipose Tissue
During lipogenesis (FA synthesis), FA are synthesized from _____ in _____ number of stages: ________ and _______
Acetyl-CoA
2
Formation and Elongation
During the first stage of Lipogenesis, we see the formation of _______ from acetyl-CoA by the enzyme _______
Malonyl-CoA
Acetyl-CoA corboxylase
During the second stage of Lipogenesis, we see the elongation in ____-carbon increments by the enzyme _______
2
Fatty Acid Synthase
During lipogenesis, acetyl-CoA Carboxylase requires what helper?
Carboxylated Biotin
During lipogenesis, the enzyme ________ functions to transfer a carboxyl group to _______ to produce ________
Transcarboxylase
Acetyl-CoA
Malonyl-CoA
During lipogenesis, Acetyl-CoA Carboxylase requires ______/_______ (from TCA cycle) for polymerization to active form
Citrate/Isocitrate
In lipogenesis, Acetyl-CoA caboxylase is inhibited by ___________, which is its ________
Polmitoyl-CoA
end-product
In lipogenesis, caboxylation of Acetyl-CoA to ______ commits to ____ _____ _____
Malonyl-CoA
Fatty Acid Synthesis
What enzyme playing a central role in the 2nd step (elongation) of FA synthesis
Fatty Acid Synthase
In the elongation step of lipogenesis, the multienzyme complex is a _____ of identical polypeptides arranged _____-__-_____
Dimer
Head-to-Tail
In the elongation step of lipogenesis, the multienzyme complex has _____ distinct enzyme activities (on each monomer) and an ____ ____ _____ that replaces CoA as the entity binds to the _______ _____ ______ _____
7
Acyl Carrier Protein (ACP)
Elongating Fatty Acid Chain
In the elongation step of lipogenesis, a long ______ group acts as a long flexible arm
Pantetheine
During the elongation step of lipogenesis, the priming of ______ group with Acetyl-CoA is followed by ________ with Malonyl-CoA, causing ______ to leave
Cysteine (Cys-SH)
Condensation
CO2
What are the three processes that occur during the elongation stage of FA synthesis
Reduction, Dehydration, Reduction
During the elongation step of lipogenesis (FA synthesis), the complex is transfered from ____ to ______
ACP
Cys-SH group
How many times is the elongation stage reaction sequence repeated?
7x total
What is the greatest size of fatty acid molecule that can be made during the elongation stage of Fatty Acid synthesis?
16- carbons, Palmitate
What is the role of Fatty Acid Elongase in the elongation of fatty acids
In the ER, elongation is carried out by fatty acid elongase (multienzyme complex)
The enzyme Fatty Acid Elongase adds ___-carbon fragments from ______ during the elongation phase of fatty acid synthesis
2
malonyl-CoA
In the Desaturase System of Fatty Acid Synthesis, desaturation requires _____, _____, and ______.
Oxygen
NADH
cytochrome b5
Where does the Desaturase System occur during fatty acid synthesis
ER
In the desaturase system of fatty acid synthesis, it is not possible to introduce double bonds between carbon atoms beyond _______-__ and the __
carbon-9
w (omega) = terminal methyl group
w-3 (linolenic acid) and w-6 (linoleic acid) or precursors, must be supplied by _____ for the synthesis of ________
Diet (vegetable oil, oily fish)
Eicosanoids (C-20 fatty acids)
What is the purpose of the Malate Shuttle
Because Acetyl-CoA cannot freely cross the inner mitochondrial membrane, and fatty acid synthesis only will occur in the cytosol, the malate shuttle is needed to allow transfer or 2-carbon units from the mitochondria to the cytosol
In the 1st step of the Malate Shuttle, ________ is decarboxylated to _______ in mitochondria
Pyruvate
Acetyl-CoA
In the 2nd step of the Malate Shuttle, acetyl-CoA reacts with oxaloacetate to form ______ in the mitochondria
Citrate
In the 3rd step of the Malate Shuttle, Citrate translocates to the cytosol via the _____-______ _______ with the transfer of ______ into the mitochondrion
malate-citrate antiporter
Malate
In the 4th step of Malate Shuttle, citrate is cleaved into ______ and ______ in cytosol
Acetyl-CoA
Oxaloacetate
In the final step of the Malate Shuttle, the enzyme _______ converts acetyl-CoA into ________ for the synthesis of fatty acids
Acetyl-CoA carboxylase
Malonyl-CoA
