1 research outputs found
Self-assembly of artificial microtubules
Understanding the complex self-assembly of biomacromolecules is a major
outstanding question. Microtubules are one example of a biopolymer that
possesses characteristics quite distinct from standard synthetic polymers that
are derived from its hierarchical structure. In order to understand how to
design and build artificial polymers that possess features similar to those of
microtubules, we have initially studied the self-assembly of model monomers
into a tubule geometry. Our model monomer has a wedge shape with lateral and
vertical binding sites that are designed to form tubules. We used molecular
dynamics simulations to study the assembly process for a range of binding site
interaction strengths. In addition to determining the optimal regime for
obtaining tubules, we have calculated a diagram of the structures that form
over a wide range of interaction strengths. Unexpectedly, we find that the
helical tubules form, even though the monomer geometry is designed for
nonhelical tubules. We present the detailed dynamics of the tubule
self-assembly process and show that the interaction strengths must be in a
limited range to allow rearrangement within clusters. We extended previous
theoretical methods to treat our system and to calculate the boundaries between
different structures in the diagram.Comment: 15 pages, 11 figure