Lecture 32 Flashcards
What is the proton motive force?
The proton gradient across the inner mitochondrial membrane produced two gradients, the first is a chemical/pH gradient (more protons in intermembrane space than matrix, meaning they will want to flow across), the second is an electrical gradient (intermembrane space more positive because of protons, pushing the positive protons to the more negative matrix). These two combined are known as the proton motive force and it provides the energy for producing ATP.
This proton gradient can be used to produce ATP without the electron transport chain, if there is another way to produce it.
What is DNP and why is it illegal?
DNP is a molecule which is non polar when deprotonated and polar when protonated, it can be used to remove the proton gradient and hence stop the proton motive force. Thereby preventing oxidative phosphorylation. The body will then send more resources in order to produce more ATP due to the lack of ATP and hence body heat will rise as the fuel is still burnt, this causes people to die.
What is ATP synthases structure and function?
ATP synthase can be seen under an electron mixroscope as a stalk with a blob on the end. Part of the structure is in the inner mitochondrial membrane (known as F0), the part in the matrix is the F1 part, this leads to the name F0F1-ATP synthase. It works as a molecular motor, turning the chemical energy into mechanical energy in order to produce ATP.
What are the main individual parts of ATP synthase?
The rotor subunits turn (part conected to stalk in F0 and stalk of F1), the stator subunits don’t turn. The turning is driven by proton flow (the proton binds to the binding sites in F0 rotor area, this leads to conformational changes in the stator catalytic alpha and beta subunits of the F1 area which enables ADP to be phosphorylated).
What are the catalytic state subunits?
The states of the catalytic subunits can be open (for release an bidning), tight (leads to ATP formation), loose (holds ADP and phosphate in preparation for catalysis). The catalytic area will have 3 sections and all forms will be had. When the catalysation happens the states will change (open to loose, loose to tight, tight to open).
Do ATP accounting for NADH and FADH2
1 ATP is made for every 4 protons pumped out. Overall this means for every NADH 2.5 ATP (10 protons) is produced, FADH2 is 1.5 (6 protons).
