The Standing Invitation

The Power of Names

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Sometimes, it is enough simply to give it a name. That is all it takes to change the way people think about something.

Of course, it helps if the name is a good one ­– or at least a big one. Here is a name that I particularly like:

“Acetyl­seryl­tyrosyl­seryl­iso­leucyl­threonyl­seryl­prolyl­seryl­glutaminyl­phenyl­alanyl­valyl­phenyl­alanyl­leucyl­seryl­seryl­valyl­tryptophyl­alanyl­aspartyl­prolyl­isoleucyl­glutamyl­leucyl­leucyl­asparaginyl­valyl­cysteinyl­threonyl­seryl­seryl­leucyl­glycyl­asparaginyl­glutaminyl­phenyl­alanyl­glutaminyl­threonyl­glutaminyl­glutaminyl­alanyl­arginyl­threonyl­threonyl­glutaminyl­valyl­glutaminyl­glutaminyl­phenyl­alanyl­seryl­glutaminyl­valyl­tryptophyl­lysyl­prolyl­phenyl­alanyl­prolyl­glutaminyl­seryl­threonyl­valyl­arginyl­phenyl­alanyl­prolyl­glycyl­aspartyl­valyl­tyrosyl­lysyl­valyl­tyrosyl­arginyl­tyrosyl­asparaginyl­alanyl­valyl­leucyl­aspartyl­prolyl­leucyl­isoleucyl­threonyl­alanyl­leucyl­leucyl­glycyl­threonyl­phenyl­alanyl­aspartyl­threonyl­arginyl­asparaginyl­arginyl­isoleucyl­isoleucyl­glutamyl­valyl­glutamyl­asparaginyl­glutaminyl­glutaminyl­seryl­prolyl­threonyl­threonyl­alanyl­glutamyl­threonyl­leucyl­aspartyl­alanyl­threonyl­arginyl­arginyl­valyl­aspartyl­aspartyl­alanyl­threonyl­valyl­alanyl­isoleucyl­arginyl­seryl­alanyl­asparaginyl­isoleucyl­asparaginyl­leucyl­valyl­asparaginyl­glutamyl­leucyl­valyl­arginyl­glycyl­threonyl­glycyl­leucyl­tyrosyl­asparaginyl­glutaminyl­asparaginyl­threonyl­phenyl­alanyl­glutamyl­seryl­methionyl­seryl­glycyl­leucyl­valyl­tryptophyl­threonyl­seryl­alanyl­prolyl­alanyl­serine.”

This is one hell of a name: 1185 letters long. Not particularly memorable, but marvellously descriptive in its own way. It is the name of a naturally-occurring molecule; following the iron rules of its etymology allows you to derive its exact chemical structure.

The name describes a very long molecule made out of a series of modules called amino acids, all strung together end-to-end like beads on a rosary. There are 22 amino acids found in nature, and they can be combined in any order to make up a protein. The protein is therefore defined by the sequence of amino acids that make it up – its primary structure. Forces between amino acids pull this immensely long thread into a tight three-dimensional tangle, generating a secondary and tertiary structures ­– the protein’s folds and creases, in which different kinds of chemistry can take place.

The name provides the primary structure, with the sequence of amino acids narrated in code: seryl is the code for the amino acid serine, tyrosyl stands for tyrosine, isoleucyl for isoleucine and so on.

Now, it would be a major synthetic challenge, but there is nothing in principle preventing us from making this molecule from scratch. Given the name, a peptide chemist (with a lot of time on her hands) could build it out of the original amino acids. The amino acids could themselves be made with crude oil drilled from the ocean floor as a starting material. Our gigantic molecule could be created afresh, in a laboratory, with no natural process involved ­– and yet the result would not just be like the molecule found in nature; it would be that molecule. The artificial form would be indistinguishable from the natural one.

Now, what is this molecule?

It is the protein coat of the Tobacco Mosaic Virus.

The protein coat is protects a strand of RNA that contains instructions, written in code for making the coat; these two things, coat and code, are all the virus is. Both have structures that are known down to the last atom. Both are reasonable targets for synthesis ­– things that could be made, from scratch, out of nothing at all.

And yet the Tobacco Mosaic Virus is a parasite, capable of self-replication in living cells. It causes disease in plants.

A lot of people would call the Tobacco Mosaic Virus a living thing. And yet it is only a molecule. Where does one end and the other begin? What is the sharp line between living matter and chemicals in jars?

Being able to give a living thing a purely chemical name highlights that there is no such line.

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Written by The S I

September 21, 2011 at 11:59 pm

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