Making FRET predictions

Making FRET predictions#

Once a donor and acceptor ACV is calculated, we can predict a mean transfer efficiency E based on the distance between the two volumes.

 E=1nmi=1nj=1m11+RA,jRD,i6/R06

Here, RD,i and RA,j are the coordinate vectors of the points i and j in the donor and acceptor volume [4, 5].

  1. R0: Förster radius of the dye pair

  2. # distances: number of distances to sample for the FRET calculation. The algorithm chooses n pairs of randomly distributed points in the donor and acceptor cloud and calculates their distance

  3. choose the donor and acceptor cloud from the drop down

  4. Calculate FRET: start the FRET calculation. The mean FRET efficiency E, the mean inter-dye distance RDA as well as the distances between the mean dye positions RMP or the two attachment sites are displayed in the table. The FRET parameters are also saved to a JSON file.

Note

The style of the ACV clouds can be tuned with the ACV visualization settings:

  • contour levels of the accessible and contact volume

  • b-factor and the gaussian resolution define the smoothness of the cloud

  • grid buffer around the ACV

  • transparency of the cloud