Phosphatase Superfamily Cys-based III

Phosphatase Classification: Superfamily Cys-based III

The superfamily consists of two member families present in human low molecular weight PTP (LWMPTP) and SSU72 families. Although human exhibits low sequence identity with proteins from any of the cysteine-based phosphatase family, except the existence of the PTP motif, the fold of the core domain is highly identical with that of LMWPTP (Figure 1E). A -CX5R- signature motif is located at the N-terminus of the protein. With the primary sequence consensus of only 15%, the overall fold of Ssu72 exhibits a Z score of 11.6 in a DALI search [36] and an rmsd (root mean square deviation) of 1.7 Å when superimposed with the main chain of LMWPTP (PDB code 1XWW) (Ssu72 6–195 excluding residues 41–96; LMWPTP 1–157 excluding residues 50–67).