One computational approach frequently used in drug discovery is "virtual screening". In this technique computational methods are used to look at a number of different small molecules and predict how well each binds to the protein. By testing the small molecules computationally, you can avoid the cost and hassle of making and testing those compounds that aren't predicted to bind the protein well.

In this example, we have a number of small molecules which bind to the Y1 receptor with different affinities. We're curious if the top scores that Foldit players can find for each molecule correlate with the ability of the small molecule to bind to the receptor. For this puzzle we have six different small molecule compounds placed in the binding site of the same protein structure, with each compound as a different multistart. Try to find the best scoring docked conformation of each of the six small molecules, and the best scoring docked conformation (best small molecule) overall.

As a ligand docking puzzle, focus on finding the best position and interactions for the ligand (the residue in the middle of the alpha helices), rather than changing the protein. It's important that you try each of the six ligands, as the ligand you start with isn't necessarily the best scoring ligand. Use the "Reset Puzzle" tool to restart the puzzle with a different ligand. Remember that you can use the "Save Solution" and "Open Solution" tools to save and go back to a particular structure/small molecule.

This is a follow on of puzzles 1441, 1446, and 1503.