Fig. 5.

Hydrophobic “spine” assembled in active kinases consists of four hydrophobic residues corresponding to four PKA residues L⁹⁵, L¹⁰⁶, Y¹⁶⁴ and F¹⁸⁵. (A) Alignment of hydrophobic residues which form the spine in 23 active eukaryotic and prokaryotic kinases (Table 2). (B) Position of the spine in PKA. The formation is shown as a red Connolly surface with probe radius of 1.4 Å. Blue spheres represent C_α atoms of the residues that lie along the “rocking” motion axis detected in molecular dynamics simulation (22).