Influence of Hydroxyproline on Mechanical Behavior of Collagen Mimetic Proteins under Fraying Deformation - Molecular Dynamics Investigations

Molecular dynamics modeling is used to simulate, model, and analyze mechanical deformation behavior and predictive properties of three different synthetic collagen proteins obtained from RSC-PDB, 1BKV, 3A08, and 2CUO, with varying concentrations of hydroxyproline (HYP). Hydroxyproline is credited with providing structural support for the collagen protein molecules. Hydroxyproline’s influence on these three synthetic collagen proteins mechanical deformation behavior and predictive properties are investigated in this paper. A detailed study and inference of the protein’s mechanical characteristics associated with HYP content are investigated through fraying deformation behavior. A calculated Gibbs free energy value (DG) of each polypeptide alpha chain that corresponds with a complete unfolding of a single polypeptide a-chain from a triple-helical protein is obtained with umbrella sampling. The force needed for complete separation of the polypeptide alpha-chain from the triple-helical protein is analyzed for proteins to understand the influence of HYP concentration and is discussed in this paper. Along with a difference in Gibbs Energy, different unfolding pathways for the molecule and individual chains are observed. The correlation between the fraying deformation mechanical characteristics and the collagen proteins hydroxyproline content is provided in this study via the three collagen proteins resulting binding energies.