Electron Transport Chain Flashcards
What is Complex I and What are the chain the electrons go?
NADH dehydrogenase. NADH to FMN to FeS clusters to Coenzyme Q (CoQ - CoQH2)
What are some properties of CoQ?
It is lipid soluble and exists in the inner mito membrane. Single electron transfers from CoQ to O2 are a major source of ROS.
What complexes directly intreat in the ETC?
I, III, and IV
What is the electron flow in complex II SDH?
Succinate to Fumarate make FADH2. FADH2 to CoQ
What is the electron flow to Complex III?
CoQH2 gives its electrons to CytB then CytB to Fe-S cluster then to free floating CytC.
What is the name of Complex III?
cytochrome b c1
What is the name of complex IV?
cytochrome c oxidase
What is the flow of electrons in complex IV?
free CytC gives to CytA. CytA to CytA3. CytA3 gives electrons to free O2 converting it to H2O.
How many hydrogens does each complex pump into the inter membrane space?
Complex I and III:4, Complex II:0, Complex IV:2
What is a superoxide?
O2-
How is a hydroxyl radical formed?
H2O2-H2O + OH radical
What is the Haber-Weiss reaction?
none enzymatic. superoxide+H202 to O2+H2O+hydroxyl radical.
What is the Fenton reaction?
H2O2 to OHrad+OH- by Fe
What is the ATPase structure?
F1 is in the matrix: 12C subunits
F2 in in the inner membrane: 3 alphabet pairs.
How is heat generated form the normal formation of ATP during ETC?
by the extra energy of the NADH to H2O reaction.
What are the three uncouplings of the ETC
Adaptive thermogenesis, chemical uncoupling, and mechanical uncoupling.
How does Adaptive thermogenesis work?
when it’s cold norepinephrine activates hormone sensitive lipase in brown fat cells. Also a proton channel called thermogenin (UCP1) is also activated which generates heat as it allows H+ to travel down it’s gradient.
What is the prototypical chemical uncoupler?
Dinitrophenol
How does mechanical uncoupling occur?
ROS and mito swelling. protons then leak through holes
Where does the energy for H+ transport come from?
the electrochemical gradient because the matrix side is - charged. the pH gradient
Example of an anti porter?
ATP/ADP
Example of a symporter?
pyruvate+H+ and Pi+H+
Example of a uniporter?
calcium
What is VDAC?
Voltage dependant ion channel
What causes and what is a mitochondrial permeability transition pore (MPTP)?
A pore that forms under hypoxia that is composed of ANT and VDAC that causes depolarization of the membrane gradients and proton gradients. Leads to apoptosis and necrosis.
