Co-assembling peptides can be crafted into supramolecular biomaterials for use in biotechnological applications, such as cell culture scaffolds, drug delivery, biosensors, and tissue engineering. Peptide co-assembly refers to the spontaneous organization of two different peptides into a supramolecular architecture. Here we use molecular dynamics simulations to quantify the effect of anionic amino acid type on co-assembly dynamics and nanofiber structure in binary CATCH(+/-) peptide systems. CATCH peptide sequences follow a general pattern: CQCFCFCFCQC, where all C’s are either a positively charged or a negatively charged amino acid. Specifically, we investigate the effect of substituting aspartic acid residues for the glutamic acid residues in the established CATCH(6E-) molecule, while keeping CATCH(6K+) unchanged. Our results show that structures consisting of CATCH(6K+) and CATCH(6D-) form flatter β-sheets, have stronger interactions between charged residues on opposing β-sheet faces, and have slower co-assembly kinetics than structures consisting of CATCH(6K+) and CATCH(6E-). Knowledge of the effect of sidechain type on assembly dynamics and fibrillar structure can help guide the development of advanced biomaterials and grant insight into sequence-to-structure relationships.
Qβ VLP simplified assembly approach uses the positively charged Rev tag to interact electrostatically with the negatively charged RNAs. This system exploits the known hairpins produced in the coat protein sequence to template the assembly of the full viral capsid.
more » « less- Award ID(s):
- 2003534
- PAR ID:
- 10476435
- Publisher / Repository:
- RSC
- Date Published:
- Journal Name:
- Journal of Materials Chemistry B
- Volume:
- 11
- Issue:
- 20
- ISSN:
- 2050-750X
- Page Range / eLocation ID:
- 4445 to 4452
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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