Modeling study of the thermostable alkaline phosphatase (FD-TAP)

The 3D structure of thermostable alkaline phosphatase (FD-TAP) was modeled based on the known X-ray structure of Escherichia coli alkaline phosphatase (BAP), using homology modeling. The rationality of resulting model of FD-TAP was validated by Ramanchandran plot and Profile-3D. On this basis, the three mutants of FD-TAP were modeled, the relationship between the energy and the thermostability of the FD-TAP and its mutants was studied by CHARMM energy. The result corresponds well with the experiments. It suggests that the decrease of the total energy and flexibility and increase of hydrophobicity of the protein by substitution of amino acids result in the increase of the thermostability.