RANDOM
The conversion of glucose-derived pyruvate into acetyl CoA
What is the linkage between glycolysis and cellular respiration?
Conversion into lactic acid or ethanol
What is the fate of pyruvate in anaerobic conditions
Preserve free energy derived from the decarboxylation step, and drive the formation of NADH and acetyl CoA.
Why must the three steps be coupled?
What is the energy-rich thioester bond?
Fatty acid degradation
What is an alternate source of acetyl CoA ?
Conversion into acetyl coenzyme A (acetyl CoA)
CO2, NADH
What does the PDH produce, and capture?
Product hydroxyethyl-TPP
What is the product of the decarboxylation reaction?
Dihydrolipoyl transacetylase (E2)
What catalyses the transfer of CoA and the formation of acetyl CoA?
Flavoproteins
What are proteins tightly associated with FAD?
Mitochondrial matrix
Where must pyruvate be transferred to be further oxidized?
TPP, liopoic acid, FAD
What are the catalytic coenzymes of PHD?
Pyruvate dehydrogenase component (E1)
What enzyme of the multienzyme complex catalyzes the rate-limiting step of the synthesis of acetyl CoA?
( also catalyzes oxidation step!)
The oxidized form of lipoamide is regenerated by E3 DIHYDROLIPOYL DEHYDROGENASE
What is step 4 of PDH?
Core of the PDH complex
Allow lipoamide to move between different active sites
Decarboxylation, oxidation, transfer of resultant acetyl group to CoA
What are the three steps of conversion of pyruvate into Acetyl CoA?
Formation of energy-rich thioester bond
What occurs during the oxidation reaction?
Amino terminus, lipoamide domain, transacetylase domain
What are the three domains of each of the subunits that make up the trimers in the Core of the PDH complex?
Inhibition of E3
What is a regulatory point of PDH complex?
Long flexible lipoamide arm of E2 subunit
What allows the three distinct active sites to work together?
Rate limiting step in the synthesis of acetyl CoA
Proximity of one enzyme to another
What increases the overall reaction rate and minimizes side reactions of PDH complex?
What does the direct binding of Acetyl CoA to E2 do to the reaction?