Conservation analysis and structure prediction of the protein serine/threonine phosphatases. Sequence similarity with diadenosine tetraphosphatase from Escherichia coli suggests homology to the protein phosphatases

摘要: A multiple sequence alignment of 44 serine/threonine-specific protein phosphatases has been performed. This reveals the position a common conserved catalytic core, location invariant residues, insertions and deletions. The used to guide improve consensus secondary-structure prediction for core. deletions aided in defining positions surface loops turns. suggests that core phosphatase structure comprises two domains: first single, beta sheet flanked by alpha helices, while second is predominantly helical. Knowledge secondary structures provides design site-directed-mutagenesis experiments will not disrupt native fold. similarity between eukaryotic serine/threonine Escherichia coli diadenosine tetraphosphatase identified. extends over N-terminal 100 residues bacteriophage E. tetraphosphatase. Residues which are amongst these classes likely be important catalysis folding. These include Arg92, Asn138, Asp59, Asp88, Gly58, Gly62, Gly87, Gly93, Gly137, His61, His139 Val90 fall into three clusters with sequences GD(IVTL)HG, GD(LYF)V(DA)RG GNH, where brackets surround alternative amino acids. predicted beta-alpha beta-beta beta-alpha-beta-beta motif. places phosphate-binding site at N-terminus helix, phosphate binding may stabilised alpha-helix dipole.