Reactions of NAD, FAD, NADP

[NiCKEL]

Why do some sources show:

 

NAD⁺ + 2H⁺ + 2e^- >>> NADH + H⁺

 

While others show

 

NAD⁺ + H⁺ + 2e^- >>> NADH?

 

I understand the H+ formed in the first one probably contributes to the proton gradient so either way the NADH molecule is the same, but why do some equations involve 2H+?

 

Also, what do the equations for FAD⁺ and NADP⁺ look like (did I write NADP correctly?)

 

I guess the real question is how many electrons each of these carry, but I'm curious to know the equation

[Xavier]

I'm assuming the question involves the electron transport chain.

So to solve the problem you need to look at complex i (NADH Dehydrogenase). Put simply NADH donates 2 electrons to FMN, which passes them on to Q10 (ubiquanone) through a series of iron-sulfate clusters. So I'm guessing that's where your 2e^- come from. Through out this process 4H+ ions are from the matrix into the intermembrain, two more are given used to reduce ubiquanone to ubiquanol.

 

So the complete equation looks something like this:

 

NADH + Q + 5H⁺ ---> NAD⁺ QH₂ + 4H⁺

 

^{(Hydrogen on the left side is in the matrix, while on the right it is in the intermembrain space.)}

 

FAD works in a similar way in complex ii compared to how FMD works in complex i. However instead of oxidizing NADH it oxidizes succinate...

 

This is from my notes so not sure how accurate they are. Just a disclaimer... 

[NiCKEL]

I'm assuming the question involves the electron transport chain.

So to solve the problem you need to look at complex i (NADH Dehydrogenase). Put simply NADH donates 2 electrons to FMN, which passes them on to Q10 (ubiquanone) through a series of iron-sulfate clusters. So I'm guessing that's where your 2e^- come from. Through out this process 4H+ ions are from the matrix into the intermembrain, two more are given used to reduce ubiquanone to ubiquanol.

 

So the complete equation looks something like this:

 

NADH + Q + 5H⁺ ---> NAD⁺ QH₂ + 4H⁺

 

^{(Hydrogen on the left side is in the matrix, while on the right it is in the intermembrain space.)}

 

FAD works in a similar way in complex ii compared to how FMD works in complex i. However instead of oxidizing NADH it oxidizes succinate...

 

This is from my notes so not sure how accurate they are. Just a disclaimer... 

Wow! We would never even have those notes lol...I hope our class is not screwed for the final. Our bio department is pretty bad, everybody basically helps themselves in class

[Xavier]

 

I'm assuming the question involves the electron transport chain.

So to solve the problem you need to look at complex i (NADH Dehydrogenase). Put simply NADH donates 2 electrons to FMN, which passes them on to Q10 (ubiquanone) through a series of iron-sulfate clusters. So I'm guessing that's where your 2e^- come from. Through out this process 4H+ ions are from the matrix into the intermembrain, two more are given used to reduce ubiquanone to ubiquanol.

 

So the complete equation looks something like this:

 

NADH + Q + 5H⁺ ---> NAD⁺ QH₂ + 4H⁺

 

^{(Hydrogen on the left side is in the matrix, while on the right it is in the intermembrain space.)}

 

FAD works in a similar way in complex ii compared to how FMD works in complex i. However instead of oxidizing NADH it oxidizes succinate...

 

This is from my notes so not sure how accurate they are. Just a disclaimer... 

Wow! We would never even have those notes lol...I hope our class is not screwed for the final. Our bio department is pretty bad, everybody basically helps themselves in class

 

 

Our bio is roughly the same, the notes are are ones I made myself while studying for my ee...