Predicting Silk Fiber Mechanical Properties through Multiscale Simulation and Protein Design

Silk
is a promising material for biomedical applications, and much
research is focused on how application-specific, mechanical properties
of silk can be designed synthetically through proper amino acid sequences
and processing parameters. This protocol describes an iterative process
between research disciplines that combines simulation, genetic synthesis,
and fiber analysis to better design silk fibers with specific mechanical
properties. Computational methods are used to assess the protein polymer
structure as it forms an interconnected fiber network through shearing
and how this process affects fiber mechanical properties. Model outcomes
are validated experimentally with the genetic design of protein polymers
that match the simulation structures, fiber fabrication from these
polymers, and mechanical testing of these fibers. Through iterative
feedback between computation, genetic synthesis, and fiber mechanical
testing, this protocol will enable a priori prediction capability
of recombinant material mechanical properties via insights from the
resulting molecular architecture of the fiber network based entirely
on the initial protein monomer composition. This style of protocol
may be applied to other fields where a research team seeks to design
a biomaterial with biomedical application-specific properties. This
protocol highlights when and how the three research groups (simulation,
synthesis, and engineering) should be interacting to arrive at the
most effective method for predictive design of their material.