MECHANICAL BEHAVIOR OF COLLAGEN MIMETIC PEPTIDES UNDER FRAYING DEFORMATION VIA MOLECULAR DYNAMICS

摘要

Collagen is a pervasive, triple helical, extracellular matrix (ECM) protein, found in human body from skin and bones to blood vessels and lungs, making it biocompatible, biodegradable, capable of cell attachment, and relevant for applications in bio-polymers, tissue engineering and a plethora of other bio-medical fields. Natural collagen's extraction from natural sources is time consuming, sometimes costly, and it is difficult to render, and could present undesired biological and pathogenic changes. Nanoscale collagen mimetic peptides (Synthetic Collagen), without the unwanted biological entities present in the medium, has shown to mimic the unique properties that are present in natural collagen. Synthetic collagen, thus provides a superior alternative compared to natural collagen for its utilization in several applications. Their properties are affected by surrounding environments, including various solvents, and can be tailored toward specific applications. The focus of this paper is to investigate the mechanical properties of these nanoscale collagen mimetic peptides with lengths of about 10nm, leading to understanding of their feasibility in bio-printing of a composite polymeric collagen biomaterial with a blend of multiple synthetic collagen molecules. Molecular dynamics modeling is used to simulate, model and analyze mechanical properties of synthetic collagen peptides. In particular, mechanical behavior of these peptides are studied. An in-depth insight into the deformation and structural properties of the collagen peptides are of innovative significance for a multitude of bio medical engineering applications. Present paper employed steered molecular dynamics as the principal method of investigating the mechanical properties of nanoscale collagen mimetic peptide 1BK.V, which closely resembles natural collagen with a shorter sequence length of 30 amino acids. A detailed comprehension of the protein's mechanical properties is investigated through fraying deformation behavior studied.. A calculated Gibbs free energy value of 40 Kcal/mol corresponds with a complete unfolding of a single alpha-helix peptide chain from a triple helical protein in case of fraying. Force needed for complete separation of the alpha-helix from the triple-helical protein is analyzed, and discussed in this paper.