HI0088 GES Hydrophobicity Scale
See below for the HI0088 GES (Goldman, Engelman and Steitz) hydrophobicity scale (Engelman, D. M., Steitz, T.A. and Goldman, A. 1986. Identifying nonpolar transmembrane helices in amino acid sequences of membrane proteins. Ann. Rev. Biophys. Biophys.Chem. 15:321-353).
The GES scale is used to identify nonpolar transbilayer helices. The curve is the average of a residue-specific hydrophobicity scale over a window of 20 residues. When the line is in the upper half of the frame (positive), it indicates a hydrophobic region and when it is in the lower half (negative), a hydrophilic region.
In the graph below the X-axis represents the length of the protein in amino acids (aa), while the Y-axis represents the GES score. The blue line shows the GES pattern of the entire protein, while the two dashed red lines represent the putative (lower line) and certain (upper line) cutoffs for potential membrane spanning domains.
Protein Length: 315 aa
Below is a numbered list showing the start and stop amnio acid (aa) positions and the
GES score given each potential membrane spanning. Those domains that have a score
above the upper cutoff are labled "Certain" while those that have a score between the
lower and upper cutoff are labled "Putative".
Helix Start Stop Score Certainty
1 7 27 0.643 Putative
2 95 115 1.639 Certain
3 147 167 0.823 Putative
4 256 276 1.440 Certain