The Biophysical Chemistry Studies of the Structure Chloroperoxidase in Present of Ionic Liquids; Molecular Dynamics Simulation Approach

Chloroperoxidase (CPO) a heme-thiolate protein secreted by the marine fungus Caldariomyces fumago, has received much attention as the most versatile known heme enzyme. The signature function of CPO is halogenation of electron-rich organic substrates [1]. Ionic Liquids (ILs) containing solvents can change the structure, stability and function of proteins. The study of protein conformation in ILs is important to understand enzymatic activity. In this work, conformational stability and activity of the enzyme in two imidazolium-based ILs (as 1-Butyl-3-methylimidazolium Bromide 1-Butyl-3-methylimidazolium methyl sulfate) were investigated. Molecular dynamics (MD) simulations were performed by the GROMACS 4.5.6 package using the GROMOS96 43A1 force field [2]. Experimental studies have shown that ILs with certain concentration increase the oxidation efficiency of this enzyme. The present study could improve our understanding of the molecular mechanism about the ionic liquid effects on the structure and activity of proteins. Root mean square deviation (RMSD), root mean square fluctuation (RMSF) and protein secondary structure were evaluated in absence and present of the ILs.