krebs cycle and oxidative phosphorlaion Flashcards
what enzymes converts pyruvate into acetyl coA
pyruvate dehydrogenase.
how does pyruvate enter the kreb cycle
acetyl COA
overall reaction of pyruvate dehydrogenase
pyruvate (3C) +CoA +NAD+ -> Acetyl CoA +NADH + H+
Pyruvate is transported from where to where
cytoplasm across mitochondrial membrane
PDH has how many subuints
5
PDH relies on what vitamine
B1
WHy does PDH rely on Vitamin B1
cofactors of PHD rely on it
why is the converstion of pyruvate to Actyle CoA irreversible. how is it made irrerverible
to drive the reaction in one direction
loss on CO2
What can PDH deficiency lead to
lactic acidosis
where does the kreb cycle occur
mitochondrial matrix
in the kreb cycle was what actyle get converted to
2CO2
kreb cycle is oxidative what cofactors does it reduce
NAD+ FAD
What energy does the kreb cycle make
GTP
How many kreb cycles for each glucose
2 as get two pyruvates
what steps of the kreb cycles are regulated
irreversible steps, steps where co2 lost
how is the kreb cycle regulated
regulated by energy availability
stimulate ADP
inhibit: ATP
what does TCA make intermediates for
biosynthesis
TCA is central catabolism pathway for what
sugars,fatty acids, ketons bodies, amino acids and alchol
what does the TCA need to fuction
o2
where has all the energy from glucose been stored
ATP glycolsis
GTP Kreb
chemical bond energ in NADH and FADH2
HIgh energy electrons in NADH and FADH2 transferred to O2 with the release of large amounts of energy
in oxidative phosphorylation O2 is reducted to
H20
Reducting powers are used in 2 ways in ATP synthesis
electrons used for ETC pump protons
free energy released used to drive atp unthesis oxidative phosphorlayion
which part of the mitochondria is the O2 reduced to H20 in
mitochondrial matrix
which part of the mitochondria is the proton gradient build up in
intermembrane space
what complexs transport the protins from the matrix to the intermembrane space of the mitchondria
proton transloacting
proton gradient across the intermembrane space is known as
proton motive force
the return of protons back to the matrix is favpured by
electrical and chemiscal gradient
protons retunr across the membrane via
ATP synthase
what is used to generate the proton gradient
the flow of electrons form the reducted cofactos to molecular oxygen
electron in which reducted coenzymes have more energy
NADH
P/O ratio of NADH
2.5
P/O ration of FADH2
1.5
Inhibition of oxidative phosphorlyation
cyanide. binds to heam in O2 blocks electron tranpsort
uncoupling of oxidatibe phosporyaltion
increase the permeability of the mitchodnrial inner membrane to protons
no ATP synthases
example of an uncoupler
dinitrophenol
ox/phos
genetics defects in proteins encoded by mitochodntraol DNA some subunits of the PTC and ATP synthase
brown adi[ose UCP1 mechanisms
noradenraline
actives liapses which releases fatty acid from triacylglycer
fatty acid oxidation NADH2/FADH2 electron transport
farry acids activates UCP1
UCP1 transport H+ back into mitochondra
