Foldit Puzzles

1765: Revisiting Puzzle 81: Calcium Ion Binding Protein

This is a throwback puzzle to the early days of Foldit. This protein, which inhibits muscle contraction in the absence of calcium ions, changes conformation in the presence of calcium to allow muscle contraction. We are revisiting old Foldit puzzles so we can see how useful the recent additions to the game have been.

1764: Symmetric Trimer Design: H-Bond Networks

H-bond Networks are back! The H-bond Network Objective encourages players to bury satisfied H-bond networks at the interface between symmetric chains. H-bond networks are a great way to introduce polar residues at the interface, but it's important that all of the bondable atoms make hydrogen bonds! In this puzzle, there are no limits on the Complex Core, but we've included the Complex Core objective so players can see which residues count as core in the H-bond Networks.

1763: Poly-Proline Helix Design: Round 1

This puzzle introduces a new secondary structure, the poly-proline helix! The starting structure is a small 38 residue protein with a frozen helix and designable residues on either end. Players should fold the starting structure to create a compact globular protein that incorporates this new type of secondary structure. Note that the backbone of the poly-proline helix has bondable oxygen atoms. If any of these oxygens are buried in the protein core, they will need to make hydrogen bonds! See the blog for more information!

1762: Revisiting Puzzle 80: Calcium Channel Blocker

This is a throwback puzzle to the early days of Foldit. This toxin is found in green mamba venom, and blocks the flow of calcium ions that normally depolarize the muscle cell to induce muscle contraction. This protein contains six cysteine residues that oxidize to form three disulfide bonds. We are revisiting old Foldit puzzles so we can see how useful the recent additions to the game have been.

1761: Symmetric Trimer Design: H-Bond Networks

H-bond Networks are back! The H-bond Network Objective encourages players to bury satisfied H-bond networks at the interface between symmetric chains. H-bond networks are a great way to introduce polar residues at the interface, but it's important that all of the bondable atoms make hydrogen bonds! In this puzzle, there are no limits on the Complex Core, but we've included the Complex Core objective so players can see which residues count as core in the H-bond Networks. There a few other objectives 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!

1760: Unsolved De-novo Freestyle 157: Symmetric Trimer

Note: This puzzle was mistakenly posted with the wrong sequence, and has been closed and reposted as Puzzle 1760b.

1760b: Unsolved De-novo Freestyle 157: Symmetric Trimer

Note: This puzzle replaces Puzzle 1760, which was mistakenly posted with the wrong sequence.

1759: Revisiting Puzzle 79: Pheromone

This is a throwback puzzle to the early days of Foldit. This pheromone protein is secreted by the protist E. raikovi to initiate conjugation, the exchange of genetic material between two cells. This protein contains ten cysteine residues that oxidize to form five disulfide bonds. We are revisiting old Foldit puzzles so we can see how useful the recent additions to the game have been.

1758: Symmetric Trimer Design: H-Bond Networks

H-bond Networks are back! The H-bond Network Objective encourages players to bury satisfied H-bond networks at the interface between symmetric chains. H-bond networks are a great way to introduce polar residues at the interface, but it's important that all of the bondable atoms make hydrogen bonds! In this puzzle, there are no limits on the Complex Core, but we've included the Complex Core objective so players can see which residues count as core in the H-bond Networks. There a few other objectives 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!

1757: Unsolved De-novo Freestyle 157

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!