Atomistic Modeling of Peptide Aggregation and β-Sheet Structuring in Corn Zein for Viscoelasticity

The structure-function relationships of plant-based proteins that give rise to desirable texture attributes in order to mimic meat products are generally unknown. In particular, it is not dear how to engineer viscoelasticity to impart cohesiveness and proper mouthfeel; however, it is known that intermolecular beta-sheet structures have the potential to enhance the viscoelastic property. Here, we investigated the propensity of selected peptide segments within common corn alpha-zein variants to maintain stable aggregates and beta-sheet structures. Simulations on dimer systems showed that stability was influenced by the initial orientation and the presence of contiguous small hydrophobic residues. Simulations using eight-peptide beta-sheet oligomers revealed that peptide sequences without proline had higher levels of beta-sheet structuring. Additionally, we identified that sequences with a dimer hydrogen-bonding density of >22% tended to have a larger percent beta-sheet conformation. These results contribute to understanding how the viscoelasticity of zein can be increased for use in plant-based meat analogues.

Automated summary

The study revealed that specific peptide segments in corn protein variants tend to maintain stable aggregates and beta-sheet structures. Simulations showed that stability is influenced by the initial orientation and the presence of contiguous small hydrophobic residues. Peptide sequences without proline may have higher levels of beta-sheet structuring.