[Guest peptide insertions into the surface loops of alkaline phosphatase]

The paper presents the description of the experiments in line with the rational concept for the "safe" insertion of guest polypeptides into the alkaline phosphatase with the minimal influence of the inserts on the enzymatic activity of the protein. Several approaches are described in the paper for the surface loop length estimation and two loops were used as the sites for guest peptides introduction by gene engineering technique. The experiments clearly demonstrate that insertions of several peptides after Ala218 of alkaline phosphatase (the site was selected by loop length analysis) do not block the activity of the enzyme. According the experimental data, the selection of the loops for the guest peptides insertion can be defined by the mobility of backbone dihedral angles during molecular dynamics simulation of alkaline phosphatase. The paper demonstrates the possibility to use in practice the estimation of loop length based on the mobility of backbone dihedral angles during molecular dynamics simulation. Indeed, it looks that the proteins with new features can be constructed by the introduction of new polypeptides into the enzymatically active proteins.