Biochem Bioenergetics Flashcards
catabolic reaction pathways (exergonic) create what? Anabolic (endergonic) pathways create what?
ATP, NADPH,
ADP, NADP+
The ∆G° is the (blank) of this reaction ∆G = ∆G° + RT·ln([Y]/[X])
rate constant
What is RT numerically?
1.364
what is the free energy equation when non-equilibrium concentrations are known?
∆G = ∆G° + RT·ln([Y]/[X])
What is the free energy equation when at equilibrium?
∆G° = -RT·lnKeq
What is the free energy equation when heat/cold or disorder are known?
∆G = ∆H – T∆S
What are the units of RT if it is 1364
cal/mol
What are the units of RT if it is 1.364
kcal/mol
∆G < 0: ?∆G > 0: ?∆H < 0: ?∆H > 0: ?
- exergonic2. endergonic3. exothermic4. endothermic
If ∆H > 0, reaction is spontaneous (∆G < 0) only if ∆S is what?
∆S > 0
What effects your ∆G°?
nothing
Will decreasing the delta G make the reaction proceed faster, lower the activation energy barrier or catalyze a reaction?
NO
What is the ∆G° of ATP hydrolysis?
-7 kcal/mol
What does glucose-6 phosphate make?
pyruvate
What makes pyruvate?
glucose-6 phosphate, lactic acid, alanine, oxaloacetate
What makes acetyl coa?
fatty acids, pyruvate, amino acids
How does creatine help out ATP?
coupled to produce ATP
How does glucose interact with ATP?
couples, makes ADP
What are four high energy compounds?
esters (Amide), thiol-esters (acetyl-coA), anhydrides (ATP), guanidium phosphata(CP), enoyl phosphate (PEP)
What electron carriers have a delta g knot of -15kcal/mol?
NADH, FADH2
The complex involved in electron transport chain are contained in (blank)
inner membrane
ATP synthase is contained in the (blank)
inner membrane
where is he pyruvate dehydrogenase complex,
matrix
What is the point of ETC?
to transfer NADH energy to molecules of ATP.
in the ETC, protons get pumped out of matrix into what?
intermembrane space
When is the reduction potential (E) positive?
for a redox pair with a tendency to acquire electrons
When is the reduction potential (E) negative?
for a redox pair with a tendency to donate electrons
What is the reduction potiential equation?
∆G° = -nF∆E°
WHat are the two types of flavoproteins?
FADH2 and FMNH2
flavoproteins can accept (blank) electrons
1 or 2
What is also called Coenzyme Q or just Q
Can accept one or two electrons
Freely diffusible within inter membrane billayer
ubiquinone
Heme cofactors in cytochromes contain Fe which can (blank).
be reduced or oxidized
What do iron sulfer centers do?
participate in electron transfer (8 different participate it in)
Recent studies support the idea the complex (blank) are associated.
I, III, and IV
What does Complex I in the electron transport chain do?
NADH transfers 2 e- to FMN and Iron sulfers centers into qh2 which pumps 4 H into intermembrane space.
How many electrons does Q accept?
2e-s
What is another name for complex I?
NADH dehydrogenase
What is the main equation of complex 1?
NADH +H+Q- _> NAD+ + QH2
ubiquinone is considrered a transfer molecule, Why?
because it transfers electrons from complex I to complex II
for 1 electron how many hydrogens get pumped through to the inter membrane space?
2
What complex in electron transport is this?
Contains four subunits, heme b, and a binding site for ubiquinone
Heme b is not on path of electron transfer and is thought to play a role in preventing electron leak
Mutations near heme b lead to hereditary paraganglioma: benign tumors in head and neck
Complex II
What complex in the ETC is the only one that is membrane bound?
Complex II
Which complex in ETC uses succinate dehydrogenase, heme b, iron-sulfer centers and binding sites for Q/QH2 and succinate?
Complex II
What complex uses NADH transfer of electrson which get transfered to FMN then to iron sulfer centers and then QH2?
complex I
(blank) is a soluble protein in the intermembrane space. It accepts electron and delivers it to complex IV
cytochrome c
What complex in the ETC has 2 cytochrome b monomorswith vaern in middle of membrane in which ubiquinone is free to move?
complex III
What complex in the ETC has cytochrome b, c and 2 ironsulfer centers and a rieske iron sulfer protein?
complex III
What complex has the following equation:
QH2 + 2cyt c (ox) + 2H+N->Q + 2 cyt c (red) + 4H+P
complex III
What complex in the ETC consists of three subunits with subunit II containing copper and SH from cystein and subunit I containing two heme groups and copper?
Complex IV
What is another name for complex IV?
cytochrome oxidase
Summarize the steps in the ETC:
NADH to ubiquinone, succinate to ubiquinone, ubiquinone to cytochrom c, cytochrome c to O2-> proton gradient and ATP
What 3 types of energy are at work in ATP synthase?
Chemical potential (ph inside is alkaline), Proton motive force, electrical potential (inside is negative)
In ATP synthase, which piece is the circle yellow piece bound to the inner membrane?
Fo
Where is the F1 piece of ATP synthase found?
inside the matrix
what makes the Fo part turn in ATP synthase?
hydrogens binding to the negative charge of it and eliciting a confirmational change
How is ATP transferred from mito matrix to cytosol?
Phosphate translocase, adenine nucleotide translocase (antiporter)
How do we get NADH from cytosol into mitochondria matrix?
in liver kidney and heart; Malate-Aspartate shuttle.
In skeletal muscle and brain: glycerol 3 phosphate shuttle (intermediates)
What inhibits electron transfer?
cyanide, CO, Rotenone, and Amytal
What inhibits ATP synthase?
oligomycin
What uncouples phosphorylation from electron transfer?
thermogenin
What are 6 agents that interfere with oxidative phophorylation?
cyanide, CO, rotenone, amytal, oligomycin, thermogenin
How does thermogenin uncouple oxidative phosphorylation?
it inserts in the membrane and allows protons that were pumped across the membrane to freely diffuse back into the matrix. Activated at points when the body temperature drops and generates Heat rather than ATP
