Modelling of active forms of protein kinases: p38--a case study.

An active form of p38 protein kinase, belonging to the mitogen-activated protein kinases subfamily, has been designed based on crystallographically known structures of two other kinases, an active form of protein kinase A (PKA) and an inactive form of extracellular signal-regulated kinase 2 (ERK2). The modelling procedure is described. Its general scheme can also be applied to other kinases. The structure of the active forms of p38 and PKA is very similar in the region which binds the substrate. The ATP-binding mode is very similar in the active forms of all the three studied kinases. Models of the active forms allow for further studies on transphosphorylation processes at the molecular level, and modelling of inhibitors competitive with ATP and/or substrates.