[akaryocyte]

The article rather understates the use of glutamate in the body.

> it is an essential building block of protein found in muscle tissue, the brain, and other organs.

It's not only found in every organ, it's present in 99.6% of all human proteins, out of 20328 only 72 do not use glutamate, and of those 29 are keratin proteins.

[ajross]

Interestingly, though (just to digress -- your point is quite valid) it's not an essential amino acid for humans. Obviously it's required to make proteins, but if we don't get enough in our diet our bodies will synthesize it.

It's just interesting that the molecule we evolved to recognize as a "protein!" marker in our food turns out not to be one of the protein submolecules we actually need to surive.

[tschwimmer]

I agree with you, but it makes sense that we may have evolved to be able to synthesize it. Since it's such a crucial amino acid, it would be an advantageous adaptation to do so.

[jannotti]

I suppose that makes sense if it's one of the easier ones to produce, so many animals can produce it. So it would be a better indicator of general protein than any of the rarer ones would be.

[tptacek]

Supposedly, the glutamate you absorb in your intestine from food is an important precursor for glutathione, which protects your mucosa from dietary toxins. It's possible that you need to consume some level of it for healthy digestion.

[Nomentatus]

Plus a neurotransmitter and a fuel as I remember. Modern domesticated plants have far larger amounts than other plants, however.