A Prelude in Protein

Researchers at the University of California, Los Angeles (UCLA), have transposed amino acids–the building blocks of proteins–into music. Studying various strings of amino acids, they have discovered short fugues, canons, and musical themes within patterns of proteins involved in a variety of molecular functions. They hope that the technique will eventually help vision-impaired people participate in the field of molecular biology.

This is not the first time that scientists have translated science into music. In the past, groups have attempted a one-to-one transposition, assigning each of the 20 amino acids a particular note, roughly spanning a two-and-a-half-octave range. Depending on the amino-acid sequence of any given protein, scientists could essentially string together notes to compose musical “pieces.” However, Jeffrey Miller, UCLA professor of microbiology, says that this method isn’t exactly pleasing to the ear.

“Most people consider ‘The Star-Spangled Banner’ beyond the typical nonprofessional singer’s voice, and that’s only an octave and a half,” says Miller. “So just imagine two and a half octaves. If you use this 20-note scale, you can have big jumps between notes, and it doesn’t sound like music.”

What’s more, the greater the span between notes, the greater the difficulty in discerning one amino acid from another. To design a more musically pleasing formula, Miller sought the help of then-undergraduate student Rie Takahashi, a molecular-biology student and trained concert pianist. Together, Miller and Takahashi came up with a more streamlined musical code.

Miller and Takahashi chose three-note chords, or triads, rather than single notes to represent each amino acid, providing a fuller sound. And instead of using the traditional one-to-one ratio, the team took a different tack to create a much smaller range. Several of the 20 different amino acids are quite similar to one another, so Miller and Takahashi assigned similar amino acids the same basic note. They then used different versions of the same chord (the same notes arranged in different positions) to distinguish between the two similar amino acids.

Finally, the team added rhythm to its musical formula. Each amino acid is genetically encoded by a string of three nucleotides, known as a codon. Each codon appears at a certain frequency in any given organism. Researchers assigned a range of codon frequencies to four different rhythmic values. The more frequently a codon appears, the longer the note value.

Once Miller and Takahashi hammered out a final formula, they tested the musical algorithm on a number of different proteins. Click here to listen to the musical score for five different proteins.

In the end, Miller and Takahashi hope that this program will make molecular biology more accessible to both a general lay audience and to vision-impaired people wanting to learn more about the field. They have set up a website where people can enter the amino-acid sequence of their choice and then receive an e-mail version of their musical “compositions.”