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Discussion Starter · #1 ·
In case of pyruvate carboxylase deficiency there are increasing of lactate, alanine, pyruvate, ketoacids. I know this fact but do not clear understand it. OK, we have lack of pyruvate carboxylase, but what prevent the pyruvate "goes to acetyl-CoA, then to citrate" for example?
 

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well i think i am not able to understand ur question fully ..... Anyways

Pyruvate carboxylase is a mitochondrail enzyme (requires ABC ATP, Biotin & Co2) & is the first rate limiting enzyme of the gluconeogenesis. So its an entry point for all the substrates for gluconeogensis in the form of pyruvate.

The other fate of pyruvate is to follow

Pyruvate -----> Acetyl CoA into the Citric acid cycle..

But this reaction is controlled by negative feedback control by Acetly CoA itself.
Also liver wants to make Glucose so there is no point in making more ATPs through the Citric Acid cycle once its requirement for ATP is fulfilled. So this would result in the accumulation of pyruvate & other substrates of gluconeogenesis.

I hope this helps...
 

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Discussion Starter · #3 ·
But this reaction is controlled by negative feedback control by Acetly CoA itself.
Thank you. Think I understood. I just didn't know (or forget ;) ) that there is feedback in the path pyruvate - >acethyl-CoA. Hmm it is very simple :redcheeks;
 
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