Figure 2.

Charge interactions of (Ser, Thr, Tyr) phospho-acceptor sites. Distributions are compared for sites that are phosphorylated in the PDB (phos) and those that are not phosphorylated (non-phos) in the same coordinate files. In these, and succeeding phos/non-phos plots, probability (p) values of the phos and non-phos distributions arising from the same underlying population were estimated with the Mann-Whitney U test. (a) 100%, no removal of sequences. (b) Sequences culled at 25% sequence identity.