This puzzle introduces the blueprint tool. The blueprint tool lets you apply predefined shapes known as "building blocks" to parts of a protein.
The blueprint tool is used in design puzzles, which are covered in more detail in the next level of intro puzzles.
Building blocks are shapes that are commonly found in the sections of loop that connect sheets and helixes in a protein. Unlike sheets and helixes, the parts of called "loop" don't have a recognizable repeating pattern of hydrogen bonds.
Loop sections have been a major problem with proteins designed by Foldit players. The Foldit science team believes that better loops are a key to designing proteins that will fold up on their own.
The building block shapes are similar shapes found in many natural proteins. Applying these shapes as part of the design should help players design better proteins.
The building blocks are specific to the secondary structure on either side of loop. There are "helix-helix" building blocks for connecting two helixes, and "sheet-sheet" building blocks for connecting two sheets. There are also "sheet-helix" and "helix-sheet" building blocks, which are different from each other. "Sheet-helix" building blocks are used when a sheet is on the left and a helix is on the right. "Helix-sheet" is used when a helix is on the left, and a sheet is on the right.
"To the left" means on the left side of the sequence display in the Blueprint.
In this puzzle, the first step is to click on the "Blueprint" button in the actions menu. This opens the Blueprint window, which shows the amino acid sequence of the protein, also known as the primary structure. The Building Blocks window opens along with the Blueprint window.
Each building block has a template of the building block on the left, and an example of what the building blocks looks like in a protein on the right. You can rotate the examples by dragging on them, and zoom in or out on them by using the mouse wheel (or shift-drag).
The puzzle has two helixes at the top. The helixes are connected by a short section of loop, containing only one segment.
To solve the puzzle, drag the first helix-helix building block template over to the sequence display in the blueprint window. A yellow rectangle appears around the section of the sequence where you applied the building block. The protein also changes shape.
The correct spot in blueprint window has a blue "D" with a red "E" to the left and a green "L" to the right. Match the blue middle of the template to the blue "D".
The puzzle is complete as soon as you apply the correct building block. If you pick the wrong building block, or put it in the wrong spot, reset the puzzle and try again.
Technical stuff: this puzzle uses ABEGO Coloring, which highlights the backbone shape of the protein. Sheets normally show up as blue in ABEGO coloring, and helixes are usually red. Loops may have a combination of red, blue, green, and yellow segments.
When the puzzle starts, the leftmost segment of the helix on the right is green, while the rest of the helix is red. The green segment is a least a potential problem. There is only one blueprint that covers two helixes with a one-segment loop between them, and it has red helix segments on either side. Applying this blueprint to the protein the helix on the right to all red segments, and makes the helix on the left angle back toward the rest of the protein.
After applying the blueprint, you may notice that the helix (formerly) on the left also has a green segment at the end. This may be OK, especially since the segment is at one end of the protein, the first segment. Also, the green segment (segment 1) happens to be proline, which tends to make the backbone curve sharply.