can the liver convert fat to aminoacids? I know it can convert fat to glucose by gluconeogenesis, but what about fat to aa?
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liver Question
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that is a very curious question but in short I think the answer is no. I didn't read this from any source, but compare the composition of a fat : glycerol (3 Carbons with 3 hydroxyl groups) and 3 fatty acids (long hydrocarbon chains with Carboxylic acid group) and Amino acid structure: central Carbon, with 4 groups [carboxyl group, amino group, Hydrogen, and variable group). Amino acids are very different from fats and unite to form proteins. The proteins in our body are largely made up of the amino acids taken up from the diet where many amino acids can not be synthesized by the body (essential amino acids). Amino acids are very unique structures and it is unlikely that fats can be converted into proteins. (Again this is just a hypothesis ).
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No, the liver cannot convert fat to amino acids, since their compositions are entirely different. Fat, however, can be hydrolyzed by lipases to their respective glycerol and fatty acid components. Glycerol can then be converted into PGAL, and fatty acids can be converted to acetyl CoA, both intermediates of cellular respiration. The only way you can get amino acids I believe, not entirely sure, are from proteins. Once the proteins are broken down into amino acids, the amino acids can undergo transamination reactions (loss of an amino group to form a-keto acids) and can eventually form acetyl CoA, pyruvate, or some other intermediate of cellular respiration. Hope that helped!
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I disagree...I think fats can be coverted into AA. Fats can be broken down into glycerol and fatty acids. Glycerol can be convrted into pyruvate, and pyruvate can be converted into AA. I dont recall the exact mechanism, but I'm about 90% sure it's possible. My physio text is in my locker. I'll check it tomorrow.
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not directly from the fatty acid, meaning its not
Fatty Acid->AA, its more like
Fatty Acid->->->->->->->->->->->->->->->->->->->->->->->->->AA
but derivatives from it yea...intermediates from the CAC and anaplerotic pathways are converted to AA[...also the urea cycle might help answer this q...]and/or the Fatty acid chains are broken down [Beta-oxidation] to acetyl Co-A and from that the liver converts it to Ketone bodies...but really do you need to know this for the DAT?
Fatty Acid->AA, its more like
Fatty Acid->->->->->->->->->->->->->->->->->->->->->->->->->AA
but derivatives from it yea...intermediates from the CAC and anaplerotic pathways are converted to AA[...also the urea cycle might help answer this q...]and/or the Fatty acid chains are broken down [Beta-oxidation] to acetyl Co-A and from that the liver converts it to Ketone bodies...but really do you need to know this for the DAT?
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not directly
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No! Liver does not convert fat to amino acid. What people are confusing is the transamination process that takes place in the liver during urea cycle. In urea cycle, oxaloacetate is a byproduct and this can be converted to an AA but only at a cost of breaking down another AA.
Incidentally oxaloacetate is a byproduct of citric acid cycle, and this can potentially come from a lipid, a carbohydrate, or even from an amino acid. So it might seem as though we are creating an AA out of a fat molecule but only at the cost of breaking down another AA.
Another way of explaining this is ... that the liver cannot create an amino group (-NH3+) using just the elements in the lipids and carbs (C, H, O). The nitrogen must come from another amino acid.
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I would hope after 6 months that the OP got his/her answer 🙂
