Electron Density puzzles consist of an unsolved protein and an electron density cloud guide, which has a transparent, globular appearance. The cloud guide is a representation of electrons emanating from the protein structure's amino acids, and provides an insight into what the native structure of the protein will look like, once solved. The guide can alternatively be changed to other viewing modes, including wireframe, and "isocontours" (or "isomesh"). The colour, transparency, density, and viewing mode of the guide can be changed, using settings located under "Actions" > "Electron Density".
The objective of Electron Density puzzles, is to fit the protein neatly into the protein's electron density cloud, so that little or no part of the protein structure sticks out of the cloud, at a medium density threshold.
These work on Windows and Mac:
- Open ED toolbox: Shift+e - Shift+e to close
- use alt-shift-click and drag to adjust the fog with the mouse over the background
- use ctrl-alt-click and drag to adjust near visibility - with the mouse over the background
- use ctrl-shift-click and drag to adjust far visibility - with the mouse over the background
- shift-q to focus on a segment with the mouse over the segment
- Purple dots: open electron density, hover, click. on tab.
Black Belt Folding Electron videos from 2013
|Karstenw and TimovanderLaan||Susume|
Protein crystallograpers course - Fitting page: Fitting refinement and validation
For a list of Electron Density puzzles that have featured on Foldit, see the Electron Density section on the Puzzle Results page.
http://en.wikipedia.org/wiki/Electron_density - Electron Density
http://en.wikipedia.org/wiki/X-ray_crystallography - X-ray Crystallography
http://www.umass.edu/molvis/edm/cloud/ - Interactive Electron Density model (requires Java)