Irc 215720 1319325279 S2 Pauldunn

An Electron Density puzzle, in solid view mode.


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.

Hot Keys

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.

Electron Density Trim


Protein crystallograpers course - Fitting page: Fitting refinement and validation

Puzzle History

For a list of Electron Density puzzles that have featured on Foldit, see the Electron Density section on the Puzzle Results page.

Exciting Electron Density Results!

More Exciting Electron Density Results!

External Links - Electron Density - X-ray Crystallography - Interactive Electron Density model (requires Java)

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