should we know about vitamin B's affect on Pyruvate dehydrogenase complex

WhittyPsyche

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I doubt it. Knowing it's a prosthetic group and why it's necessary should be enough.

Even more doubtful that the PDC co enzymes is required knowledge, never encountered it.


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Leumas8

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Pretty sure the fact that lipoic acid is a co-enzyme showed up in the section bank. So may not be a bad idea to memorize them. 5 coenzymes for PDH are NAD+, FAD, CoA, Lipoic Acid, Thiamine Pyrophosphate
 
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WhittyPsyche

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Pretty sure the fact that lipoic acid is a co-enzyme showed up in the section bank. So may not be a bad idea to memorize them. 5 coenzymes for PDH are NAD+, FAD, CoA, Lipoic Acid, Thiamine Pyrophosphate
It wasn't an explicit question though. The passage gave all the details necessary.


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This information will be given to you in a passage. Sure you can waste time and memorize it to save time on the off chance it shows up - very possible for anything mitochondrial related - but your time would probably be better spent memorizing cell signaling pathways and even more so by doing practice passages.
 
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My issue with that though was I knew about the 5 co-factors but the question on the section bank required you to link lipoic acid back to the PDC complex. It cant hurt not knowing. Just another thing to memorize
 

WhittyPsyche

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Did it? what did it say in the passage?
Are you asking me to recite the passage?

I did not memorize them and I know I didn't have to have that knowledge to answer, it was reasoned from the passage. If you'd like to search through the SB and come paste the question feel free. I can find a better use of my time, and it wouldn't change the fact that knowing Thiamine is a prosthetic group in the PDC should be sufficient knowledge.


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wizzed101

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Are you asking me to recite the passage?

I did not memorize them and I know I didn't have to have that knowledge to answer, it was reasoned from the passage. If you'd like to search through the SB and come paste the question feel free. I can find a better use of my time, and it wouldn't change the fact that knowing Thiamine is a prosthetic group in the PDC should be sufficient knowledge.


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I must be illiterate and/or very stupid. I can't for the life of mine find in that passage anything related to PDC complex much less lipoic acid. O wise scholar please enlighten me how you "reasoned" to arrive at that answer.
 

WhittyPsyche

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I must be illiterate and/or very stupid. I can't for the life of mine find in that passage anything related to PDC complex much less lipoic acid. O wise scholar please enlighten me how you "reasoned" to arrive at that answer.
You are really something special. I'll repeat. AAMC materials did not require memorization of the co enzymes. I never memorized them and did not have an issue. Most information was given in the passage. Again, I DID NOT memorize any of it, and had no issue.

Being that I did the SB weeks ago, and already took my exam, I am not going to search through 100 questions to find the exact question to tickle your fancy. If that's how you want to spend your time, feel free.

As someone else also mentioned, it's more important to know the pathway and why certain steps are needed. So again, at the end of the day, it is not NECESSARY to memorize all the coenzymes and every single detail about them. And back to OPs original question, AGAIN, knowing thiamine is a prosthetic group that participates in the PDC is literally all you need to know.

So should we go over this one more time for good times sake or nah?


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Leumas8

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Holy hardo, chill out
 
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I looked it up. It is passage 12 #94 in the B/B section Bank. So the way you would answer this is using the passage for slight information and ruling out the answer choices. You are required to know the cofactors for Glycolysis and Citric Acid cycle as well as knowing which steps are KEY metabolic steps. The way I answered this was by ruling out all the answers that could not be true. So you did not require knowledge of this particular topic, you were required to understand glycolysis the TCA cycle in order to realize that they could not be the correct answers. Hope this helps
 

wizzed101

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You are really something special. I'll repeat. AAMC materials did not require memorization of the co enzymes. I never memorized them and did not have an issue. Most information was given in the passage. Again, I DID NOT memorize any of it, and had no issue.

Being that I did the SB weeks ago, and already took my exam, I am not going to search through 100 questions to find the exact question to tickle your fancy. If that's how you want to spend your time, feel free.

As someone else also mentioned, it's more important to know the pathway and why certain steps are needed. So again, at the end of the day, it is not NECESSARY to memorize all the coenzymes and every single detail about them. And back to OPs original question, AGAIN, knowing thiamine is a prosthetic group that participates in the PDC is literally all you need to know.

So should we go over this one more time for good times sake or nah?


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Quality discourse, scholar.
@Roayer o really?! Wow, I just looked at the question again. I didn't realize that oxaloacetate to phosphoenolpyruvate is a key step in Glycolysis/Citric acid cycle! These biochem textbooks are full of lies!!!!!

How exactly did you eliminate the other 3 options, btw?
 
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WhittyPsyche

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Quality discourse, scholar.
@Roayer o really?! Wow, I just looked at the question again. I didn't realize that oxaloacetate to phosphoenolpyruvate is a key step in Glycolysis/Citric acid cycle! These biochem textbooks are full of lies!!!!!

How exactly did you eliminate the other 3 options, btw?
Lmao you are such a special apple. I'm sure you could find a better use of your time there bud.


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Quality discourse, scholar.
@Roayer o really?! Wow, I just looked at the question again. I didn't realize that oxaloacetate to phosphoenolpyruvate is a key step in Glycolysis/Citric acid cycle! These biochem textbooks are full of lies!!!!!

How exactly did you eliminate the other 3 options, btw?
Lol that is gluconeogenesis sorry I didn't clarify that, you are supposed to know that pathway as well in depth. Go to page 544. And I eliminated the other options because you are supposed to know each step in glycolysis/gluconeogenesis/TCA and those steps don't need that so I crossed them out.
http://50.30.47.15/Ebook/Course_SUST_BMB/BMB_121/Lehninger_Principles_of_Biochemistry.pdf
 
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wizzed101

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Lol that is gluconeogenesis sorry I didn't clarify that, you are supposed to know that pathway as well in depth. Go to page 544. And I eliminated the other options because you are supposed to know each step in glycolysis/gluconeogenesis/TCA and those steps don't need that so I crossed them out.
http://50.30.47.15/Ebook/Course_SUST_BMB/BMB_121/Lehninger_Principles_of_Biochemistry.pdf
Those steps don't need what? Did you mean the enzymes for each of those step can be made without using such and such cofactors? On top of that, you need to know know which cofactors can be made endogenously? But somehow, knowing how PDC works is out of scope? If you have taken a biochem course, I am pretty sure that PDC is a very important topic and it is frankly quite fascinating.

@WhittyPsyche Idk man. The other guy has helped located the Q so it's pretty easy to check. Or did you imply that I did not know oxaloacetate/phosphoenolpyruvate on top of my head? Stop!!!!

BTW, you can better use your time by just saying that "IDK what the question is and what the passage was about, but I am pretty sure it's was NOT a discrete question because I was touched by an apple." instead of that quality discourse, scholar.
 
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Those steps don't need what? Did you mean the enzymes for each of those step can be made without using such and such cofactors? On top of that, you need to know know which cofactors can be made endogenously? But somehow, knowing how PDC works is out of scope? If you have taken a biochem course, I am pretty sure that PDC is a very important topic and it is frankly quite fascinating.

@WhittyPsyche Idk man. The other guy has helped located the Q so it's pretty easy to check. Or did you imply that I did not know oxaloacetate/phosphoenolpyruvate on top of my head? Stop!!!!

BTW, you can better use your time by just saying that "IDK what the question is and what the passage was about, but I am pretty sure it's was NOT a discrete question because I was touched by an apple." instead of that quality discourse, scholar.
PDC is rather important but I don't believe it was in the Official Guide topic list. I took Biochem 1 (not 2 so I never covered it). I did briefly learn metabolism and don't recall that Lipoic acid was a cofactor for those specific steps. I don't think you need to know which cofactors can be made endogenously. It won't hurt but yeah you most likely don't need to know it. It would be more improtant to understand the role of the cofactors as presented in a passage. Example would be how Mg2+ stabilizes the active site for some of the reactions. And yeah I don't believe PDC was mentioned in the OG.
 

wizzed101

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The question was written with that knowledge in mind, if you read the answer. It is quite easy tbh.

All enzymes are always made endogenously because they are proteins. The cofactors (not all of them) can be thought of as "non-protein." The question asked what happened if the body cannot make fat effectively. Of the three enzymes listed, only the PDC needs fat to work. The swinging arm mechanism is like the coolest feature of the PDC, and is imo the most defining.

BUT are we supposed to know that? If so, what other cool things we also need to know?

Edit: and to the OP, no you don't need to know that.