Overview[]
Because glycine is the most flexible amino acid (due to its lack of a sidechain), it will respond readily and rather predictably to manipulation. The glycine hinge is a tactic used to shape a section of a loop containing at least one glycine. It is most useful when a player has some idea of where other secondary structures should go, and wants to bend the loop in a way that will put them in the appropriate places while not dragging down the local score too much.
Procedure[]
First, freeze the amino acids next to the glycine, while leaving the glycine unfrozen. Then band the frozen amino acids in the direction you'd like them to move — this will correspond to the way you want the hinge to bend. Finally, global wiggle. The glycine will usually flex into a new shape, and if this helps your compactness, hydrophobicity, or hydrogen bond arrangement, the score will often go up!
Notes[]
- If you don't gain points at first from a glycine hinge, don't despair. Release the bands, unlock the puzzle, and global wiggle again. Often a glycine hinge will get you points on the rebound.
- The glycine hinge works because (apparently) there are few points to be gained or lost by bending a glycine.
- If you want to keep the glycine bent after applying the hinge, lock it while unlocking the rest of the hinge. Then global or local wiggle.