Amino Acid Etymology

Students are often required to know something about each of twenty amino acids. There are various mnemonic devices to remember which name goes with each structure. Valine, for example, has an isopropyl side chain which resembles the letter "V".

Sometimes etymology is a better mnemonic device. "Valine", for example, has something to do with valeric acid, which doesn't help me much, but it might help someone who knows more than I do about organic chemistry. Maybe some reader can offer a comment about this. "Valeric", in turn, is derived from the name of a Roman emperor.

"Proline" is interesting. It's short for pyrrolidine-2-carbolylic acid. This amino acid is unique in that its side chain is attached, not only to the alpha carbon, but also to the nitrogen that is attached to the alpha carbon. Pyrrolidine is hydrogenated pyrrole. This is a helpful mnemonic device for someone who already knows what pyrrole is.

Threonine has a four carbon backbone which is slightly reminiscent of threose, which is an isomer (and not quite an anagram) of erythrose, which is derived from the Greek word for "red" as in "erythrocyte".

The etymology of an amino acid may not be a useful mnemonic device for everyone, but it has a certain charm and is always related to the history of that compound. Besides, by studying etymology, you are learning something worthwhile, not just cramming for a test.

I invite readers to leave comments about other amino acids. You don't need to be registered to leave a comment here.