#Japan #Kanazawa University #Kanazawa #Nanomaterials #peptide organization

Unveiling the Role of Water in Peptide Self-Organization on 2D Nanomaterials

Researchers at the Nano Life Science Institute (WPI-NanoLSI) of Kanazawa University recently made headlines with their insightful study featured in the journal Small. The team, led by Ayhan Yurtsever, Takeshi Fukuma, and Linhao Sun, investigated how short peptides self-assemble in a linear fashion on atomically-thin surfaces such as graphite and molybdenum disulfide (MoS₂). This pioneering work addresses a significant challenge in materials science, focusing on the intricate relationships between peptides and solid substrates, along with the crucial role that local hydration layers play in shaping nanoarchitectures.

The essence of biotechnology rests in harnessing the unique properties and functionalities of various biological molecules, which often necessitates their arrangement on non-biological surfaces. This requirement poses challenges, especially since the mechanisms driving self-assembly on solid substrates remain poorly understood. The Kanazawa University team employed advanced visualization techniques and computer simulations to delve deep into these processes. Their findings point to the importance of the solvent, particularly water, in guiding the assembly of these peptide structures.

They constructed simple dipeptides comprised of alternating amino acids—tyrosine and histidine. Tyrosine is hydrophobic, fostering a water-repellent environment, whereas histidine is hydrophilic, attracting water. The researchers varied the number of repeating units to observe how these peptides adopt linear, crystalline structures that align with the atomic lattices of 2D materials.

Utilizing frequency-modulated atomic force microscopy (FM-AFM), the researchers visually captured the assembly of Tyr-His dipeptides on surfaces of graphite and MoS₂. Remarkably, they noted that the lengths of assembled peptides with their associated hydration layers coincided with the peptides' extended states. This highlights the synergistic interplay between aromatic interactions and solvation effects, fundamentally guiding peptide self-assembly. The study emphasizes water's dual role in not only facilitating intermolecular hydrogen bonding but also providing the flexibility that peptides require to adapt during assembly.

Advanced 3D-AFM techniques were employed to illustrate the three-dimensional structure of water surrounding peptide assemblies. This approach revealed complex hydration shells that encapsulate the peptide structures—features that are vital for selective molecular recognition and can mediate interactions with other biomolecules. Molecular dynamics simulations provided further details into the hydrogen bond networks stabilizing these hydration layers.

The research opens new doors for the rational design and functional control of peptide-based hybrid materials. These well-ordered peptide lattices hold potential for organizing inorganic nanoparticles with sub-nanometer precision, which might lead to exploring quantum mechanical effects. Additionally, the specific spatial arrangement of side chains in the peptides could help create active sites that mimic natural enzymatic functions and facilitate high-performance catalytic interfaces for electrochemical applications, thus illuminating the future of bioelectronics.

The focus of the research team now shifts toward understanding how local hydration structures influence the peptide assembly process. This pursuit could pave the way for advancements in the intricate dance between hydrophobic and hydrophilic amino acid sequences and their interactions with water at solid interfaces.

In conclusion, this innovative work from Kanazawa University marks a significant leap in our understanding of peptide organization on solid substrates, opening an array of possibilities for future applications in the fields of biomedical sciences, bioengineering, and nanotechnology.

Acknowledgments

This research was supported by various grants from Japan’s Ministry of Education, Culture, Sports, Science, and Technology (MEXT) and the Research Council of Finland, among other initiatives. The collaboration with international scientists highlights the global effort in advancing nanotechnology and biotechnology.

References

Ayhan Yurtsever et al., "Supramolecular Assembly and Interfacial Hydration of Tandem Repeat Dipeptides on 2D Nanomaterials Insights from 3D-AFM Measurements and MD Simulations," Small, 2025, DOI: 10.1002/smll.202501785.

For more information, please visit NanoLSI Kanazawa University.