WhatsMissing
An AlphaFold model usually shows one protein chain — and that is often not the whole machine. The real molecule may need a cofactor (like a haem), a metal ion, or other chains it works with, and none of those are in the single-chain picture. For each model below, spot what is missing, then see the live UniProt annotation prove it. Everything runs locally; nothing about you is collected.
This is the tool. Your answer is checked against the protein’s live UniProt Cofactor / Subunit annotations. The proteins are listed below (works without JavaScript). A native version, when it ships, adds offline use; it never gates the web.
Loading the game… If it does not start, the guide below still works.
How to play. Press Start. Pick what the single-chain model leaves out (click an option or press its number). The live UniProt annotation is revealed and your answer is scored. Press Enter or Next. There is no way to lose.
Why the missing pieces matter
The single chain AlphaFold predicts is often not the working protein: myoglobin and haemoglobin hold oxygen only on the iron of their haem, SOD1 needs its copper and zinc ions to break down superoxide, and haemoglobin carries oxygen as a four-chain assembly. Many SOD1 variants linked to inherited ALS weaken how the protein holds its metals or pairs into its two-chain dimer.
A model is a starting point, not the whole machine
AlphaFold predicts the shape of a protein chain. Many proteins only work with extra parts a chain-only model does not include: an iron-carrying haem, a metal ion in the active site, or several copies assembled together. Reading a single-chain model as "the whole thing" is a common misreading — and this game trains the habit of asking "what is left out?".
The proteins
Answer key — open it after you play
| Protein | What the single-chain model leaves out |
|---|---|
| Hemoglobin (beta subunit) HBB · P68871 | The haem group + the other 3 chains (α₂β₂) |
| Myoglobin MB · P02144 | The haem group |
| Superoxide dismutase (Cu-Zn) SOD1 · P00441 | The copper + zinc ions |
| Catalase CAT · P04040 | The haem group and a bound NADPH (and it is four chains) |
| Lysozyme C LYZ · P61626 | Nothing big: it works as one chain with no cofactor, so the model is the whole thing |
Methods & about
This is a teaching game and a simplification. The reveal fetches the protein’s live UniProt Cofactor and Subunit annotations as evidence; the structure is the real AlphaFold prediction. No score history, no accounts, nothing sent anywhere.
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