Skip to main content
. 2006 Aug 2;34(13):3646–3659. doi: 10.1093/nar/gkl395

Figure 2.

Figure 2

Evaluation of the structural alphabet. (A) The accumulated (κ, α) matrix of 225 523 segments derived from the pair database. This matrix, 648 cells (36 × 18), is clustered into 23 groups based on the similarity of representative segments of each cell using a NNC method. A representative structural letter is assigned for each group. (B) The representative 3D fragments of 23 structural letters. These 23 segments are roughly divided into five categories: helix letters (A, Y, B, C and D), helix-like letters (G, I and L), strand letters (E, F and H), strand-like letters (K and N) and others.