Individual Final Project
Metabolizing Heartbreak
Main Idea
The day we broke up, I recorded my heartbeat. I have always been afraid to look back on those losses, sorrows, betrayals and pains. But each time I truly do, it gives me a sense of release about things that are not eternal. The memory of that heartbreak in my heart is like a bowl of Meng Po soup - when I truly face it, that part has gradually faded away. I began to think: Could this memory be turned into a ritual of food? I encoded that day’s heartbeat into an ATGC sequence, implanted it into probiotics, and let it enter my intestines. The stomach has always been an organ of emotion - when people feel nervous and anxious, it is always the first to react. If the memory I swallowed could be transformed into a calming substance there, helping me release and relax, and ensuring I never repeat the same mistakes - that would be the Meng Po soup in the sense of synthetic biology.
system logic
Mengpo Soup is an engineered probiotic system. Users record their heartbeats during a moment of emotional breakdown, and this heartbeat data is encoded into a DNA sequence and edited into the plasmid of E. coli Nissle 1917. This strain of bacteria carries a molecular sensing circuit: when the host re-enters a high-stress state, the concentration of norepinephrine in the gut increases, activating the sensing system. The heartbeat sequence begins to be transcribed into RNA, triggering the toehold switch to open, and the downstream GAD gene is expressed, producing GABA, making the body feel calm.
The Process
Encoding the Body: From Heartbeat to DNA On March 29, 2026, 100 heart rate readings were recorded via Apple Watch across a single day — a day of personal significance. The data spans 12:21 to 22:45, with a several-hour gap in the middle that coincides with the most emotionally intense period of the day.
Step 1 — Modeling the rhythm The heart rate data is fitted to a Simple Harmonic Motion equation: x(t) = mean + A · cos(ωt + φ) This treats the heartbeat as a biological oscillator, extracting three parameters that together describe the rhythm of that day: ∙ A = 24.46 BPM — the amplitude of emotional fluctuation ∙ ω = 0.2848 rad/hr — the frequency, corresponding to a full cycle of approximately 22 hours ∙ φ = −0.568 rad — the phase offset, shaped by the silence in the middle The gap in recording is not treated as missing data. It is preserved in the model as a structural trace — embedded in the phase parameter as a period of arrested motion.
Step 2 — Quantization Each parameter is normalized within a defined biological range and mapped to an integer between 0 and 255, using 8 bits of precision.
Step 3 — Binary to nucleotide Each integer is converted to 8-bit binary. Every two bits are then translated into a nucleotide base:
00 → A
01 → T
10 → G
11 → C
The sequence The three parameters produce a 12-base sequence:
TCCTAGTTGGA
Flanked by neutral spacers for biological stability:
AAAA TCCTAGTTGGA AAAA
Step 4 — Inserted into GFP This sequence has been inserted into the non-coding region of a GFP reporter plasmid (pZE21-GFPaav, Addgene #26643), downstream of the rrnB T1 terminator — a location where it coexists with the fluorescent protein machinery without interfering with its function.
What this sequence holds The encoding is fully reversible. Given only these 12 bases, the original SHM parameters can be reconstructed, and from them, the heart rate curve of that day can be redrawn. The 22-hour cycle encoded in ω is not coincidental. It is the duration of the emotional arc of that day — from the peak at 12:29, through the silence, to the quiet of late evening. One oscillation. One day. One ending.