TCA Cycle Flashcards
What happens to pyruvate in aerobic conditions?
converts to acetyl coenzyme A
what does Acetyl CoA do?
Links glycolysis from cytoplasm to krebs in matrix of mitochondria
What cells lack mitochondria?
RBC - only perform glycolysis
What is each pyruvic acid converted to?
2 carbon acetyl group
How is acetyl coA made?
remove 1 molecule of co2 as waste so NAD+ to NADH
What is the net gain from glycolysis and link reaction?
2 ATP - 4 NADH - 2 Acetyl coA
What is pyruvate dehydrogenase deficiency?
sex linked disease
build up of lactic acid in body (lactic acidosis)
nausea vomiting - neuro problems
What occurs in krebs cycle?
Redox and decarboxylation reactions
What do redox reactions do?
Transfer energy to NAD and FAD
How many ATP molecules in krebs?
12 ATP - 24 per glucose
What does acetyl group in krebs cycle do?
Generates 6 carbon molecule citrate - coA recycled
What does acetyl group entry create?
citrate and regenerates coA
What happens to citrate?
Isomerisation to isocitric acid
Where does oxidative decarboxylation occur?
Remove CO2 and forms NADH and alphae ketoglutarate from isocitrate dehydrogenase
Where does substrate level phosphorylation occur?
from succinyl coA displaced for phosphate transferred to GDP and donated to ATP forms succinate
Where does dehydration occur?
succinate oxidised to furmarate by FADH2 formation
Where does hydration occur?
Furmurate converted to malate by adding water
What does dehydrogenation do?
converts to oxaloacetate and forms NADH
Which enzyme allows substrate level phosphorylation?
succinyl coA synthetase
What does regulation of TCA depend on?
substrate availability
inhibition by product accumulation
allosteric inhibition
What is citrate synthase inhibited by?
Citrate and ATP