preparation for the cycle

pyrvuate can be converted to acetyl coa in the

mitochondria

under — condition, pyruvate can enter —- —-

aerobic

mitochondria matrix

pyruvate that enters the mitochondira matrix is converted to — — by

acetyl coa

pyruvate dehydrogenase

acetyl coa is the fuel for the

CAC

what does cac do

processes the two carbon acetyl unit to 2 molecules of co2

what does cac generate

8 high energy electrons that can form atp

the formation of acetyl coa from pyruvate is —- in animal cells

irreversible

what does cac commits the acetyl group towards (4)

tricarboxylic acid (tca)

cac

krebs cycle

fatty acid synthesis

PDH releases

co2 and 2 e'-

the formation of acetyl coa from pyruvate is — in animal cells

irreversible

the pyruvate dehydrogenase complex includes

3 enzymes and 5 cofactors

what are the three steps of acetyl coa from pyruvate

decarboxylation

oxidation

transfer to coa

decarboxylation done by

e1

oxidation done by

e1/e2

transfer to coa done by

e2

decarboxylation is catalyzed by

TPP

tpp is the cofactor found in

pyruvate dehydrogenase (E1)

tpp derived from

vitamin b1 thiamine

what is unique abt tpp

the positive charge nitrogen stabalized its carbanion form making it a good nucleophile

in the oxidation state, the two carbon —- is oxidized and transfered to —- —- —— —

hydroxyethyl

E2 core dihydrolipoamide arm

what does the oxidation form

acetyl-lipoamide

what is the acetyl lipoamide formation catalyzed by

e1 component

the —- —- —- can easily form carbanion

hydroxyethyl-tpp adduct

in the transfer of acetyl to coa, —- catalyzes the transfer of the —- from the —- —- to —— to form ——

e2, acetyl group, acetyl-lipoamide,coenzyme a, acetyl coa

in step 3, the —- arm swings back to the active site of the —- —

lipoamide

e2 core

— catalyzes the transfer of the — group from the —- —- to —- —- to form ——

e1

acetyl

acetyl lipoamide

coenzyme a

acetyl-coa

the reoxidation of reduced dihydrolipoamide is catalyzed by

E3 (dihydrolipamide dehydrogenase)

what is the equation for the reoxidation of reduced dihydrolipamide

dihydrolipamide + fad → lipoamide+ fadh → fad + nadh + h+

enzyme —- is a key site of regulation

e1

how is e1 inactivated

kinase (pdh kinase) associated with the complex phosphorylates and inactivates e1

how is e1 activated

phosphatase, also associated with the complex, removes the phosphate and thereby activates the enzyme

what inibits pdh allosterically

acetyl coa

nadh

what activates pdh kinase, thus inhibiting pdh

high atp

acetyl coa

nadh

what stimulated pdh by inhibiting pdh kinase

adp and pyruvate

what can stimulate pdh by activating pdh phosphatase

ca2+

what can stimulate pdh in liver and adipose tissue? how?

insulin

activating pdh phosphatase

what does insulin provide

acetyl coa precursor for fatty acid syntehsis

thiamine (b1) deficiency results in insufficent — and reudced

TPP

pyruvate dehydrogenase (e1) activity

— and —- inhibit —— —— —- by binding to the two —- of the ——

mercy and arsenite

pyruvate dehydrogenase complex

sulfurs

e2 (dihydrolipoamide)