Protein kinases signatures and profile

Eukaryotic protein kinases [1,2,3,4,5] are enzymes that belong to a very extensive family of proteins which share a conserved catalytic core common to both serine/threonine and tyrosine protein kinases. There are a number of conserved regions in the catalytic domain of protein kinases. We have selected two of these regions to build signature patterns. The first region, which is located in the N-terminal extremity of the catalytic domain, is a glycine-rich stretch of residues in the vicinity of a lysine residue, which has been shown to be involved in ATP binding. The second region, which is located in the central part of the catalytic domain, contains a conserved aspartic acid residue which is important for the catalytic activity of the enzyme [6]; we have derived two signature patterns for that region: one specific for serine/ threonine kinases and the other for tyrosine kinases. We also developed a profile which is based on the alignment in [1] and covers the entire catalytic domain.