(647c) Designing Sequence Controlled Polymers for Biomineralization: A Predictive Approach Using Molecular Dynamics Simulations
Peptoids, a class of N-glycine substituted peptidomimetic polymers have been successfully employed to produce gold nanoparticles as well as dentin tubules in vitro due to the ability to precisely define peptoid sidechain sequences to mimic their peptide or protein counterpart. Additionally, the absence of backbone hydrogen bonds in peptoids enables explicit interactions through the side chains, leading to highly predictable macroscopic functions through a controlled microscopic structure. Motivated by the fact that R5 is an intrinsically disordered peptide without the backbone significantly impacting its functionality, we designed a peptoid mimic that bears the same sidechain sequence as R5 (referred to as Rp5), to test the conditions under which it may undergo biomineralization. We study Rp5 under five distinct conditions (1) wild type Rp5 (2) Rp5 with phosphate ions (3) Rp5 with phosphorylation on Ser1 (4) Rp5 with phosphorylation on Ser14 (5) globally phosphorylated Rp5. Enhanced sampling using Parallel Bias Metadynamics with Partitioned Families (PBMetaD-PF) was employed to ensure convergence of the energy landscape. Free energies of dimerization, and conformation of the dimers was calculated. This work can inform the rational design of sequence-controlled polymers for biomineralization.