This symmetric design puzzle has C2 symmetry, with two symmetric chains. The H-bond Network Filter encourages players to bury satisfied H-bond networks at the interface between the two chains. There a couple other filters in effect; see the puzzle comments for details. The Baker Lab will run folding predictions on your solutions for this puzzle, and those that perform well will be synthesized in the lab. Remember, you can use the Upload for Scientists button for up to 5 designs that you want us to look at, even if they are not the best-scoring solutions!

This is a throwback puzzle to the early days of Foldit. This protein helps to transfer electrons between substrates in bacteria. The protein is modeled here in reducing conditions, and no disulfides are expected to form. We are revisiting old Foldit puzzles so we can see how useful the recent additions to the game have been.

We are giving you this Parabacteroides Distasonis protein as an extended chain. The native is shown as a guide on this puzzle, so try using everything you have learned in the Intro levels to match the native fold. Hints and details are posted in the puzzle comments. For players with fewer than 150 global points.

The structure of this protein is still unknown. Secondary structure predictions (from PSIPRED) are marked on the starting structure, and provide clues about where the protein might form helices and sheets!

We are giving you this currently unsolved short protein as an extended chain. It has only 48 residues and we're posting it with no secondary structure predictions. For players with fewer than 150 global points.

This small unsolved Arabidopsis protein only has 59 residues and negatively controls the biosynthesis of starch in plants and regulates leaf and seed composition. We are giving you 5 starts for this puzzle. Resetting the puzzle will cycle through these 5 Zhang server predictions. They are also in the Alignment Tool so you can use partial threading as well as an extended chain. For players with fewer than 150 global points.

This is a small symmetric trimer design puzzle. A symmetric protein relies not only on how well folded each part is, but also on how well they interface together. Your changes will be reflected in the symmetric unit. Make sure you have completed Intro Puzzle 5-2, and 7-1 through 7-4. For players with fewer than 150 global points.

We are giving you a helix positioned over a hydrophobic groove where binding occurs in nature. You can mutate any residue on the helix but none on the native binding region. Try to look for favorable hydrophobic interactions in this groove while maintaining the helix. For players with fewer than 150 global points.

In electron density puzzles, we give you some experimental data to help you find the correct fold. This data takes the form of an electron density, and appears in game as a guide. You can adjust the guide visualization by going to [Actions]>[Electron Density]. For players with fewer than 150 global points.

This symmetric design puzzle has C2 symmetry, with two symmetric chains. The H-bond Network Filter encourages players to bury satisfied H-bond networks at the interface between the two chains. There a couple other filters in effect; see the puzzle comments for details. The Baker Lab will run folding predictions on your solutions for this puzzle, and those that perform well will be synthesized in the lab. Remember, you can use the Upload for Scientists button for up to 5 designs that you want us to look at, even if they are not the best-scoring solutions!