Closed

This is the fourth puzzle in the designable linker series! We are providing parts of two of the best-known designed binders to the SARS-CoV-2 spike, and are challenging players to link them together with a rigid linker! The two helical bundles are the parts of the two binders. They are currently connected with a flexible alanine linker that needs to be redesigned. We have also included the parts of the actual spike that are within 15 angstroms of the termini of the binders, so you know what regions your binder has to avoid to prevent clashing. The big thing for puzzles like these is to have buried hydrophobics at the interface between the linker and the binder helices. Packing the linker against the helices can help it maintain its shape.

Note: Due to strange behavior and frequent hangs, this puzzle has been reduced to zero points. Players should not feel compelled to play it for competitive reasons. However, the results of this puzzle have exceptional scientific value, so the puzzle will remain active for those who wish to keep working. Once we find and fix the bugs, we intend to repost the puzzle so that players may load previous work and continue competitive play.

This is a throwback puzzle to the early days of Foldit. This enzyme helps to regenerate a cofactor that is necessary for nucleic acid synthesis; the starting structure is a model produced by Rosetta. This protein contains only one cysteine, so no disulfide bonds are expected. We are revisiting old Foldit puzzles so we can see how useful the recent additions to the game have been.

Note: This puzzle replaces Puzzle 1918, which had some scoring problems. Unfortunately, players may not load solutions from the original Puzzle 1918.

Note: This puzzle was closed early due to some scoring problems, and has been reposted as Puzzle 1918b. Players may not load solutions into the reposted puzzle.

Note: This puzzle replaces Puzzle 1916, which revealed a bug in the Contact Surface metric. This puzzle lacks the Contact Surface metric, but players may load solutions from the original Puzzle 1916.

Note: This puzzle was closed early due to a bug in the Contact Surface metric, and is reposted as Puzzle 1916b. Players may load solutions from this puzzle into the reposted version.

This is a throwback puzzle to the early days of Foldit. This protein was evolved in vitro to bind testosterone; the starting structure is a model produced by Rosetta. This protein contains two cysteine residues, which oxidize to form a single disulfide bond. We are revisiting old Foldit puzzles so we can see how useful the recent additions to the game have been and to provide newer players with problems that are still scientifically relevant.

This is the second puzzle in the designable linker series! We are providing parts of two of the best-known designed binders to the SARS-CoV-2 spike, and are challenging players to link them together with a rigid linker! The two helical bundles are the parts of the two binders. They are currently connected with a flexible alanine linker that needs to be redesigned. We have also included the parts of the actual spike that are within 20 angstroms of the termini of the helices on the binders, so you know what regions your binder has to avoid to prevent clashing. The designable helices are a possible starting point for your linker designs.

This is a throwback puzzle to the early days of Foldit. This protein helps to regulate oxidation in the cell; the starting structure is a model produced by Rosetta. This protein contains two cysteine residues, which oxidize to form a single disulfide bond. We are revisiting old Foldit puzzles so we can see how useful the recent additions to the game have been and to provide newer players with puzzles that are still scientifically relevant.