Valentin Sereda1, Nicole M Ralbovsky1, Milana C Vasudev2, Rajesh R Naik3, Igor K Lednev1. 1. Department of Chemistry, University at Albany, SUNY, 1400 Washington Avenue, Albany, NY 12222, United States. 2. Department of Bioengineering, University of Massachusetts Dartmouth, 285 Old Westport Road, Dartmouth MA 02747, United States. 3. Soft Matter Materials Branch, Materials and Manufacturing Directorate, Wright-Patterson Air Force Base, Dayton, Ohio 45433, United States.
Abstract
Self-assembly of short peptides into nanostructures has become an important strategy for the bottom-up fabrication of nanomaterials. Significant interest to such peptide-based building blocks is due to the opportunity to control the structure and properties of well-structured nanotubes, nanofibrils, and hydrogels. X-ray crystallography and solution NMR, two major tools of structural biology, have significant limitations when applied to peptide nanotubes because of their non-crystalline structure and large weight. Polarized Raman spectroscopy was utilized for structural characterization of well-aligned D-Diphenylalanine nanotubes. The orientation of selected chemical groups relative to the main axis of the nanotube was determined. Specifically, the C-N bond of CNH3+groups is oriented parallel to the nanotube axis, the peptides' carbonyl groups are tilted at approximately 54° from the axis and the COO- groups run perpendicular to the axis. The determined orientation of chemical groups allowed the understanding of the orientation of D-diphenylalanine molecule that is consistent with its equilibrium conformation. The obtained data indicate that there is only one orientation of D-diphenylalanine molecules with respect to the nanotube main axis.
Self-assembly of short peptides into nanostructures has become an important strategy for the bottom-up fabrication of nanomaterials. Significant interest to such peptin class="Chemical">de-based building blocks is due to the opportunity to control the structure and properties of well-structured nanotubes, nanofibrils, and hydrogels. X-ray crystallography and solution NMR, two major tools of structural biology, have significant limitations when applied to peptide nanotubes because of their non-crystalline structure and large weight. Polarized Raman spectroscopy was utilized for structural characterization of well-alignedD-Diphenylalanine nanotubes. The orientation of selected chemical groups relative to the main axis of the nanotube was determined. Specifically, the C-N bond of CNH3+groups is oriented parallel to the nanotube axis, the peptides' carbonyl groups are tilted at approximately 54° from the axis and the COO- groups run perpendicular to the axis. The determined orientation of chemical groups allowed the understanding of the orientation of D-diphenylalanine molecule that is consistent with its equilibrium conformation. The obtaineddata indicate that there is only one orientation of D-diphenylalanine molecules with respect to the nanotube main axis.
Authors: Sawsan Almohammed; Agata Fularz; Mohammed Benali Kanoun; Souraya Goumri-Said; Abdullah Aljaafari; Brian J Rodriguez; James H Rice Journal: ACS Appl Mater Interfaces Date: 2022-03-07 Impact factor: 9.229