Brief Answer:
Welcome to HCM. I have reviewed your question

Detailed Answer:
I am sorry for the delay. My answer was erased completely and I must start over.

Briefly, the length of time an amino acid stays in the body is variable dependent on many factors. Amino acids are transformed into several pathways and other needed chemicals such as enzymes, hormones, blood.

There are nine amino acids that must be consumed every day out of the 20 needed to make a complete protein. So, these amino acids are not stored, or immortal.
These 9 are: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. Amino acids are not recycled to other amino acids.

Proteins and amino acids as well as peptides are eventually "transformed" or degraded. So the amino acid may exist in another format therefore, in some manner, extending its mortality in another chemical format, but no, there are no immortal amino acids.

Unlike fat and starch, the human body does not store excess amino acids for later use—the amino acids must be in the food every day. The 10 amino acids that we can produce are alanine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, proline, serine and tyrosine.

It is your DNA that codes for the proteins that we can make.

However, all things die. We do not have any "immortal" proteins or amino acids.
There is a time when the body degrades and/or transforms until death.

I hope I have addressed your question. If satisfied, please close and rate.
Sincerely, XXXXXXX Shattler, MS, RDN

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Brief Answer:
Welcome back

Detailed Answer:
The distribution of amino acids is complex. You ask a very difficult question as amino acids are in flux with constant degradation and transformation.

You mention cartilage where there is little turnover, it does make sense that the degradation process in amino acids might occur at a slower rate. However, I doubt if original amino acids from childhood are still present.

As we age amino acids are either replaced more slowly or just become reduced. Sometimes amino acids do not degrade, but change isomers, which disturbs the originality.

Consider that by the time you are 50 you have a 90% chance there is a visible change in your cartilage. This means original amino acids are gone.

I feel you are getting into longevity research. You might want to check out the TOR pathway details and the mechanisms of action of the the SIRT 1 enzymes as it relates to slowing down the aging process aside from the protective effects of these pathways on chronic disease prevention.

I wish I could help you further. Regards, XXXXXXX Shattler, MS,RDN

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Brief Answer:
Hi! Great Train of Thought

Detailed Answer:
I, too, am interested in theoretical and quantum physics, biology and physiology, so lets put our thinking caps on.

Yes, at some level it seems possible, but I do not believe at this point scientifically plausible, that some form of that same structure (amino acid), some carbon atom, still randomly exists in a new formation elsewhere originating from childhood.

After thinking about it,however, another variable should be considered. If 90% of your cartilage is changed, what happened with the other 10% I asked myself. Then I queried myself as to how prions (mad cow disease, wasting syndrome), composed entirely of protein material, can be transmitted as an infectious agent from host to child unchanged and I questioned my answer to you.

It is that no one has ever asked me this, I never really thought about it and this is the most interesting question I have had in awhile. So, after giving it some thought, I do see examples where proteins are surviving through generations, at least infectious prions are so why not other proteins???

This is the best I can come up with on such short notice. Would love to enjoy a conversation with you sometime. Please don't forget to close and rate the question, although I don't know of how much help I have been. Most Respectfully, XXXXXXX Shattler, MS,RDN

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