Bchm Exam 4: Citric Acid Cycle

where does the citric acid cycle mainly occur (7 of 8 steps)

mitochondrial matrix

sources of acetyl-CoA for the citric acid cycle

fatty acids, amino acids, and glucose (carbs)

what is reaction 1 of the citric acid cycle

citrate synthase adds the acetyl group of acetyl-CoA to oxaloacetate to create citrate

what is the enzyme of the citric acid first step

citrate synthase

what is reaction 2 of the citric acid

aconitase isomerizes citrate to isocritate (dehydrate citrate and rehydrate aconitate to isocitrate)

what is reaction 3 of the citric acid cycle

isocrite dehydrogenase release the first CO2 while isocrite is oxidized to alpha-Ketoglutarate and NAD+ is reduced to NADH

what is reaction 4 of the citric acid cycle

alpha-ketoglutarate oxidative decarboxylation which releases the second CO2 - alpha ketoglutarate is oxidized to succinyl-CoA and NAD+ is reduced to NADH

what is reaction 5 of the citric acid cycle

succinyl-CoA synthetase catalyzes subtrate level phosphorylation- GTP/ATP is generated to form succinate

what is reaction 6 of the citric acid cycle

succinate dehydrogenase generate ubiquinol by oxidizing succinate to fumarate and reducing FAD to FADH2 which reduces Q to QH2

what is important to remember about the enzyme of reaction 6

succinate dehydrogenase is found in the inner mitochondrial membrane

what is reaction 7 of the citric acid cycle

fumarase catalyzes a hydration reaction turning fumarate to malate by adding water

what is reaction 8 of the citric acid cycle

malate dehydrogenase regnerates oxaloacetate by oxidizing malate to oxaloacetate and reducing NAD+ to NADH

what are the products of the citric acid cycle

3 NADH, 1 FADH2, 1 GTP, 2 CO2

what are the 3 regulated enzymes of the citric acid cycle

citrate synthase, alpha ketoglutarate DH, and isocitrate DH

what are anaplerotic reactions in relation to the citric acid cycle

chemical reactions that replenish intermediates (pyruvate to oxaloacetate)

how to turn of the citric acid cycle

high levels of ATP/NADH

how to turn on the citric acid cycle

high levels of ADP/NAD+