Helixfold
Bend a chain of residues across a grid so the hydrophobic units huddle into a buried core — and squeeze the energy down to its proven minimum.
How to play
A protein is modelled as a chain of hydrophobic (H) and polar (P) residues on a 2D lattice. Hydrophobic neighbours that sit adjacent without being bonded lower the energy. Your goal is to fold the chain so the H residues form a compact core and you hit the optimum energy.
- Click a residue to pivot the tail of the chain around it.
- Alternate-click the same residue to pivot in the opposite direction.
- Use the Spin button to flip the default pivot direction (clockwise / counter-clockwise).
- Reach the provable minimum energy for the chain to win the puzzle.
Controls
- Desktop: click residues to pivot, click again to reverse, toggle Spin, and use Reset to straighten out.
- Phone & tablet: tap residues to pivot — fully touch-friendly.
Tips & strategy
- Count H-H contacts, not shape — each non-bonded hydrophobic pair that ends up adjacent drops the energy.
- Aim for a compact blob rather than a long arm; surface area exposed by H residues is wasted energy.
- When a fold stalls, reset and try seeding the core from the densest cluster of H residues first.
What you'll learn
Helixfold is built on the classic hydrophobic-polar lattice model of protein folding, turning the search for a fold into a puzzle.
- Skills: biochemistry, protein folding, the HP model, optimization
- Best for: advanced high school / college
- For parents & teachers: the HP model of protein folding.
About Helixfold
Helixfold is built on the classic hydrophobic-polar lattice model of protein folding, turning the search for a minimum-energy conformation into a tactile puzzle. It's an original, free browser game with three chain lengths and daily plus practice modes.
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