Ion Effect and Metal-Coordinated Cross-Linking for Multiscale Design of Nereis Jaw Inspired Mechanomutable Materials.
The Nvjp-1 protein is a key component in the jaws of Nereis virens, a species of marine worm. It contains over 25 mol % of histidine, which is believed to play a key role in the metal-coordinated cross-linking responsible for the structural stability and exceptional mechanical performance of the worm jaw. Understanding the nanoscale mechanism behind this cross-linking and its pathway in affecting the macroscopic mechanical behavior of the material is crucial to develop bioinspired mechanomutable materials based on Nvjp-1. Here, we use a combination of multiscale modeling and experimental synthesis to understand the behavior of this heterologous-expressed protein from the nano- to the macroscale. We have built a bottom-up molecular-based model, which includes electronic-based density functional theory calculations, atomistic simulation of the nanoscale properties with replica exchange molecular dynamics, and an elastic network model for describing the macroscale behavior at different pHs. This multiscale modeling supports the experimental synthesis of a photo-cross-linked Nvjp-1 hydrogel by proving both the nanoscale mechanisms and mechanical behavior predictions. Our theoretical results agree well with the experimental observations, showing that Nvjp-1 forms a more compact structure in the presence of Zn2+ions with a suitable pH environment, leading to the formation of more stable intramolecular metal-coordinated cross-links. These metal-coordinated cross-links induce nanoscale aggregation of Nvjp-1, which is responsible for the hydrogel contraction observed in experiments and predicted by the model.
Laboratory for Atomistic and Molecular Mechanics, Department of Civil and Environmental Engineering, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
Chia-Ching
CC
Chou
Laboratory for Atomistic and Molecular Mechanics, Department of Civil and Environmental Engineering, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
Francisco J
FJ
Martin-Martinez
Laboratory for Atomistic and Molecular Mechanics, Department of Civil and Environmental Engineering, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
Zhao
Z
Qin
Air Force Research Laboratory, Materials and Manufacturing Directorate , Wright-Patterson AFB, Ohio 45433, United States.
Patrick B
PB
Dennis
Air Force Research Laboratory, Materials and Manufacturing Directorate , Wright-Patterson AFB, Ohio 45433, United States.
Maneesh K
MK
Gupta
Air Force Research Laboratory, Materials and Manufacturing Directorate , Wright-Patterson AFB, Ohio 45433, United States.
Rajesh R
0000-0002-7677-928X
RR
Naik
Laboratory for Atomistic and Molecular Mechanics, Department of Civil and Environmental Engineering, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
Markus J
0000-0002-4173-9659
MJ
Buehler
D000818:Animals; D056831:Coordination Complexes / Q000737:chemistry*; D003432:Cross-Linking Reagents / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007477:Ions / Q000737:chemistry; D007568:Jaw / Q000737:chemistry*; D011077:Polychaeta; D066329:Protein Aggregates; D011506:Proteins / Q000737:chemistry; D011789:Quantum Theory; D015032:Zinc / Q000737:chemistry*
D056831:Coordination Complexes; D003432:Cross-Linking Reagents; D007477:Ions; D066329:Protein Aggregates; D011506:Proteins; D015032:Zinc
Nereis jaw; Nvjp-1 protein; metal coordination; molecular dynamics; network model