catabolism of pyruvate Flashcards
where does the citric acid cycle occur
matrix of mitochondria
what makes NADH and FADH
dehydrogenases
what increases when hunrgy
glucagon, epinephrine and cortosol
further oxidation of pyruvate
enters mitochodnria and pyruvate dehydorgenase takes a carbon and 2 o2s from pyruvate and adds co-a mkaing acetyl co-a
role of pyruvate dehydrogenase
takes a carobn and 2o2s from pyruvate and adds co-a making acetyl co-a
what is simultaneously occuring during make up of acetyl co-a
2e- are transferred to nad+ in the from of a hydride ion making NADH
last step of further oxidation of pyruvate
carbon and 2 co2s are released to form co2
first step of citric acid cycle
acetyl co-a binds with oxaloacetate(4 carbon) by citrate synthase to make citrate (6 carbon)
what is released during the first process of citric acid cycle
co-enzyme A
role of aconitase
rearanges citrate to make its isomer isocitrate
isocitrarte dehydrogenase role
removes a carbon and 202s from isocitrate
rate limitng step
isocitrarte dehydrogenase
what also happens in the process of isocitrate dehydrogenase
two electrons are also transferred to a nearby NAD+, in the form of a hydride ion, making our first NADH, and the carbon and oxygens give us our first CO2, leaving us with a 5-carbon molecule called alpha ketoglutarate
what can inhibit isocitrate dehydorgenase
High levels of ATP and NADH in the cell
what stimulates isocitrate dehydorgenase
high levels of ADP, an ATP precursor
does calcium activate or inhibit isocitrate dehydrogenase
activates as calcium rises during muscle contraction
role of called alpha ketoglutarate dehydrogenase
converts the 5-carbon alpha-ketoglutarate to the 4-carbon succinyl-CoA, releasing our 2nd molecule of NADH and CO2 in the process
role of succinate thiokinase
removes the CoA from succinyl CoA, turning it into a 4-carbon succinate molecule
how is the first GTP made
succinate thiokinase couples a phosphate and GDP molecule to the reaction, making GTP
succinate dehydrogenase role
transforms succinate to fumarate
what is also happening durig succinate dehydrogenase role
two electrons and two protons are transferred to FAD to produce FADH2
fumarate hydrase role
adds a water molecule to fumarate, making malate.
how is malate converted to oxaloactete
by the enzyme malate dehydrogenase making our 3rd and final NADH in the process
do hormones play a role in the regulation
no
what does the citric acid cycle yield
3NADH; 3 ATP per so 9
1 FADH2; 2 ATP
2 CO2; 1 ATP
12 ATP
how many acetyl coa made from glucose
2 so 24 atp
