Scientists Create Music From the Molecules of Life
Making sense of complex science is not always easy, and the perception that science is a difficult subject can lead individuals to veer away from studying and pursuing a career in the field.
Methods of science communication are becoming increasingly creative to help break down scientific concepts into bitesize, easily digestible pieces of information. Yu Zong Chen, professor in the department of pharmacy at the National University of Singapore and Peng Zhang, currently a post-doc at the Rockefeller University have perhaps taken innovation to the next level, creating melodies based upon the structure of proteins. Their research is published in Heliyon.
"Music together with visual art are the most popular ways for humans to express, propagate and perceive our feelings about, and our understanding of, the world, events and ourselves. Science is generally perceived by the public as something hard to understand. By mapping a basic element of life (As proteins are the work horses of life) to music, the general public can hear the sound of life at a microscopic level, and perceive what science sounds like," Chen told Technology Networks.
What are proteins?
Proteins play an essential role in all living organisms. They are complex biological molecules directly involved in many structural, metabolic, transport, immune, signaling and regulatory processes. Proteins are synthesized from a DNA template through a series of steps including transcription and translation.
How do we turn proteins into music?
Turning protein structure into music may sound complicated, but if we look closely at how proteins are built, and how music is made, there are some parallels. "Protein structure is like a folded chain, and this chain is composed of small units called amino acids," Zhang explained.
There are 20 different amino acids that are all labeled with an alphabetic label. "A protein chain can be denoted as a string of these alphabetic letters, very much like a string of music notes in alphabetical notation," added Zhang. Protein chains fold and wave into patterns that ultimately support their function. These patterns contain ups, downs, turns and loops. "Music string is with sound waves of higher and lower pitches, tempos and repeats. Using algorithms, scientists can map the string of amino acid structural and chemical features into a string of musical features."
This isn't a novel concept. However previous attempts haven't focused on a particular music style, and so the outcome hasn't been the most enjoyable audio experience. The existing algorithms use a simple approach of mapping the strings of amino acid features onto fundamental music features, such as note length and pitches. However, this mapping does not work well with complex musical features like harmony and rhythm.
A breakdown of protein-to-music algorithm methods:
1) Generate the distribution maps of the musical features
2) Generate the distribution maps of amino acid features
3) Compare the maps of musical features and the maps of amino acid features to find which amino acid features best match each musical feature
4) Use the matched amino acid features for mapping to each musical feature.
In this study, Chen and colleagues focused on classical music so that they could guide more complex mappings of different amino acid features to the strong characteristics of this music style.
"Classical music generally presents lighter, homophonic, graceful and emotive melodies. Some of these strong characteristics may be exploited as enforceable guide for protein-to-music mapping. We specifically selected the Romantic period classical music, which typically spans a wide range of the piano keys with features such as chromaticism and chords," Chen said. He added that music from the mid-1800s Romantic period is typically highly emotive, which enabled the researchers to test a great range of different piano keys in their algorithm.
Which proteins to choose?
There are a vast number of different proteins – scientists are still debating just how many exist in the human body. Chen and colleagues focused on 18 proteins belonging to two different groups. The first group of 11 proteins were selected as their functions are involved in emotion, cognition, sensation and performance, consistent with the lighter, more homophonic and graceful characteristics of classical music. The second group have more diverse functions, such as photosynthesis, fluorescence, food proteins and disease, representing the different "aspects" and "states” of life.
Four pieces of mid-1800s Romantic classical music were analyzed, including Fantasie-Impromptu from Chopin and Wanderer Fantasy from Franz Schubert.
The music produced was complex, with notable variations in pitch, loudness and rhythm, Chen described. No two pieces are alike due to the unique amino acid sequences, so each protein produces a distinct melody. The researchers also discovered that interesting patterns can emerge when making music in this way. "The music generated from the oxytocin receptor has some recurring motifs due to the repetition of certain smaller sequences of amino acids within the protein sequence. Some music also sounds more chromatic than others; the music generated from the cellular tumor antigen p53 is highly chromatic, and there are particularly fascinating phrases where the music sounds almost toccata-like, repeating and ‘developing’ a motif," Chen said. Music created from the M protein of the coronavirus – which defines the shape of the viral envelope – utilizes a large range of keys, particularly in the bass.
Inspiring a greater understanding of the molecules of life
The scientists hope that their music pieces can draw more attention to the molecules of life, and that it will inspire further research in the future. "Our protein-to-music mapping algorithms were developed with respect to a limited number of classical music pieces, and the algorithms were fined-tuned based on the opinion of a smaller number of people," said Chen. "A better protein-to-music mapping algorithm may be developed by using a greater number of music pieces and consultation with more diverse groups of people," he concluded.
Yu Zong Chen and Peng Zhang were speaking to Molly Campbell, Science Writer for Technology Networks. The authors would like to acknowledge Nicole Tay and Fanxi Liu from Raffles Institution Singapore for their efforts.
Reference: WanNi Tay N et al. Protein music of enhanced musicality by music style guided exploration of diverse amino acid properties. Heliyon. 2021. doi: 10.1016/j.heliyon.2021.e07933.