Foldit Puzzles

1997: TGF Receptor Binder Design: Round 4

Design a protein that can bind to the TGF-beta receptor! We saw some excellent designs in the previous Round 3 puzzle, so this puzzle is set up just the same. Try to max out the Contact Surface Objective by using sidechains that pack closely against the target binding site!

1995: Symmetric Trimer Design: H-bond Networks

Design a symmetric protein trimer, with 3 identical chains of 60 residues each! This puzzle includes a Secondary Structure Objective, so no more than 50% of your design can form helices. The H-bond Network Objective encourages players to build buried, 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! We've also adjusted the H-bond Network Objective so that poor-scoring H-bonds may not contribute to networks; poor-scoring H-bonds will be displayed in red. This puzzle uses the Buried Unsats Objective, with a large penalty for buried polar atoms that can't make H-bonds. In this puzzle, there are no limits on the Complex Core, but we've included the Complex Core objective so players can see the core residues that can be incorporated into H-bond Networks.

1994: Influenza HA Binder Design: Round 6

Design a protein to bind to influenza virus! This puzzle is set up similar to the Round 5, but we've increased the Contact Surface goal to 500.

1993: Revisiting Puzzle 64: Thioredoxin

This is a throwback puzzle to the early days of Foldit. This human protein helps to regulate the reduction potential of the cell, and should be modeled here in reduced form (with no disulfide bonds). We are revisiting old Foldit puzzles so we can see how useful the recent additions to the game have been.

1992: Symmetric D2 Tetramer Design: H-bond Networks

Design a D2 symmetric protein tetramer, with 4 identical chains that assemble together! Unlike the cyclical C4 symmetry that we are used to, the proteins in this puzzle will come together as a "dimer of dimers" with D2 symmetry. The H-bond Network Objective encourages players to build buried, 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! We've also adjusted the H-bond Network Objective so that poor-scoring H-bonds may not contribute to networks; poor-scoring H-bonds will be displayed in red. This puzzle uses the Buried Unsats Objective, with a large penalty for buried polar atoms that can't make H-bonds. In this puzzle, there are no limits on the Complex Core, but we've included the Complex Core objective so players can see the core residues that can be incorporated into H-bond Networks.

1991: TGF Receptor Binder Design: Round 3

Design a protein that can bind to the TGF-beta receptor! We saw some excellent designs in the previous Round 2 puzzle, so this puzzle is set up just the same. Try to max out the Contact Surface Objective by using sidechains that pack closely against the target binding site!

1990: TNK1 with Density: Round 2

Fold this TNK1 protein into the electron density map! This is a follow up to Puzzle 1984, now starting from the crystallographer's best model. We want to know if you can improve it!

1989: Symmetric Tetramer Design: H-bond Networks

Design a symmetric protein tetramer, with 4 identical chains that assemble together! This puzzle includes a Secondary Structure Objective, so no more than 50% of your design can form helices. The H-bond Network Objective encourages players to build buried, 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! We've also adjusted the H-bond Network Objective so that poor-scoring H-bonds may not contribute to networks; poor-scoring H-bonds will be displayed in red. This puzzle uses the Buried Unsats Objective, with a large penalty for buried polar atoms that can't make H-bonds. In this puzzle, there are no limits on the Complex Core, but we've included the Complex Core objective so players can see the core residues that can be incorporated into H-bond Networks.

1988: Tie2 Binder Design: Round 3

Design a protein to bind to the Tie2 receptor! This puzzle is much like the Round 1 puzzle, except that we've increased the threshold for the Contact Surface Objective. Aim for a Contact Surface value of at least 500!

1987: Revisiting Puzzle 63: Spinach Protein

This is a throwback puzzle to the early days of Foldit. This spinach protein is critical for photosynthesis, and participates in the electron transfer chain within the chloroplast. The protein is modeled here in the reduced state, so 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.