The effects of removal of manganese ions on the structure of the enzyme chloroperoxidase

Chloroperoxidase (CPO) is the most versatile of the knownheme enzymes [1]. This enzyme has amanganese ions in its structure [2]. We have carried out molecular dynamics (MD) simulation studies onthe removal of manganese(Mn2+) and studied its effect on the CPO. In this study protein secondarystructure, root-mean-square deviation of atomic positions(RMSD), root mean square fluctuation (RMSF)and contact map were studied before and after the removal of manganese and corresponding graphs weredrawn. The study of secondary structure of protein showed that with manganese removal, three of aminoacids were rearranged in 3.1 Helix, and the percent of alpha helix, extended and isolated bridge in theprotein secondary structure are decreased, while the percent of coil and turn are increased. The results ofthe RMSD diagram showed that the presence of manganese does not have a large impact on the on thestability of the tertiary structure of the CPO. The results of the RMSF diagram showed that the removalof manganese very effective on amino acid binding site and C-terminal.

کلیدواژه ها:

Chloroperoxidase ، molecular dynamics simulation ، manganese ، protein secondary structure ، contact map