abstract
| - NULL OR PIVOT POINT PULLING Null point pulling can help you get that last final point. This technique is to very gently disturb the protein while running wiggle backbone or wiggle all. First you must find the center segment of the protein chain. This null point is different from the Q point which is a point of view and is not the null point. The null point is the center segment of the protein chain with the coordinates (0, 0, 0) or the very center point of the X, Y, Z plot of the evolving 3D computed protein's structure. The segments nearest the null point seem anchored and will not move as easily as segments further from this center point. The ends of the protein are easily moved, and will fold and move about freely. If a frozen sheet contains this central null point segment, you will not be able to move it or twist it with bands. It well remain anchored in place. You will need to pull the rest of your protein to it. The other way to find the null point sometimes is by gently pulling on various parts of the protein and noting where the center of rotation is, and what part of the protein is not moving when you pull on the rest. This null point can be located near a exposed hydrophobic on a hairpin turn near the outside of the molicule. This point of least movement is the null point. When pulling on the null point segment of the backbone, the protein should not move about; if it does, you have pulled too hard and you should reset your highest score and start over. As you gently pull on the null point and while running backbone wiggle at the same time, wheel click on the null segment to draw a band and drag it gently in small circles. Do not lift your finger. continue to gently pull on the band, jiggling and gently shaking the mouse in different directions and strengths away from the segment. watch your score and pull in the direction that makes your score climb. This will gently shake the protein and allow it to settle into a new minimum, gaining those last few precious fractions. More Techniques at > The Foldit Labs
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