Citric acid cycle Flashcards
What are the subunits of pyruvate dehydrogenase and what do they do?
E1=decarboxylates
E2= binds CoA to acetyl
E3= forms NADH from NAD
How does high ADP/ low ATP affect pyruvate dehydrogenase?
Upregulates it to produce more Acetyl CoA
How does low ADP/ high ATP affect pyruvate dehydrogenase?
Down regulates it to produce mroe Acetyul CoA
How many decarboxylations occur in the citric acid cycle?
2xCO2 are released.
How many electron carriers are formed?
3x NADH and 1x FADH2
Via which intermediate is ATP directly formed in the citric acid cycle?
Via GTP
Where do the two control points within the citric acid cycle occur?
at non-reversible reactions.
How is isocitrate dehydrogenase regulated
Allosterically by ATP, ADP and NADH concentrations
How is alpha ketoglutarate regulated?
Allosterically regulated by ATP, NADH and succinyl CoA concentrations.
What does amphibolic mean and how is it related to the citric acid cycle?
It is both catabolic and anabolic. It forms molecules as well as breaking them down.
What can the citric acid cycle form?
Nucleotide bases, haeme groups and amino acids.
What happens when the citric acid cycle intermediates are used in the formation of other molecules?
They must be replenished gluconeogeneis with anapleurotic reactions.
