Protein Composition: Translating Amino Acid Sequences into Music

Proteins are composed of individual building blocks (amino acids) assembled in a chain, resembling beads on a string. This string - or sequence of amino acids - folds into a unique three-dimensional shape to form a fully functional protein. In nature, there are 20 different naturally occurring amino acids. I assigned specific musical chords to each different amino acid and arranged the chords sequentially in an order that mirrored the sequence of amino acids. The resulting composition contains a pattern of chords representative of the protein's amino acid sequence. For example, if Glycine (one of the 20 natural amino acids) is assigned to a 'C' chord and Tryptophan (another amino acid) is assigned to a 'G' chord, a sequence of Glycine-Tryptophan-Glycine would produce a chord pattern of C-G-C. Chords were assigned based on the relative frequency of amino acids within the protein (i.e., amino acids that occur more often in the protein will be assigned chords more central to the chosen key). Amino acids with similar properties were assigned similar chords. Variations in note duration were determined by the DNA sequence of the protein, with the most frequent codons (unique combinations of three DNA building blocks) corresponding to shorter note durations and vice versa. To further diversify the composition, differences in note volume were determined by membrane topology (protein segment location within a cell). For this project, I focused on a protein called transmembrane channel-like protein 1 (TMC1), which is composed of 760 amino acids. TMC1 is an essential protein in the hearing process in humans; at least 40 different mutations in this protein lead to progressive hearing loss or deafness. While a few of these mutations are extreme, resulting in a severely shortened protein, most of the mutations causing hearing loss or deafness are simple substitutions: the exchange of one amino acid for another. Such mutations do not alter the final length of the protein, but instead change a single amino acid. Similar to how one wrong note can modify the character of an entire composition, even a miniscule alteration in protein structure can lead to drastic changes on the organismal level. Converting proteins into musical compositions allows for a more intuitive comparison between functioning and disease-causing proteins. Translating proteins into musical compositions is an exciting new area of research currently studied at MIT. This program has built a musical library of numerous different proteins for use in training an artificial intelligence program to recognize and understand protein structure. Based on the observed parameters, the AI creates original musical arrangements that can be translated into novel, theoretically functional proteins. Such endeavors are aimed at better understanding protein folding and mutation for use in disease research. Not only is this approach a more intuitive way to think about protein structures, it also has the added benefit of sharing science with a wider audience, specifically those without a scientific background and those who are visually impaired.