Molecular Dynamics Study of 3-Dimensional Domain Swapping Process of Cytochrome c

Abstract

A 3-dimensional domain swapping (3D-DS) phenomenon is a promising way to make a stable multimer because interactions in the multimer is about the same as that of a monomer; it would be useful to artificially design a functional protein's multimer. In this study, molecular dynamics (MD) simulation of cytochrome c(cyt c) that is known to form a 3D-DS dimer (PDB ID: 3NBS) was performed to study factors that enhance 3D-DS structure sampling. Our results show a difficulty of 3D-DS structure sampling and a necessity of a method such as the generalized ensemble method. The results also show the importance of a loop-flexibility to sample 3D-DS structure; when the bond and torsion angle potential coefficients are less than 10% of secondary structure, 3D-DS structures become easy to sample.