| Autor: |
Weeks WB; Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, United States., Buchanan LE; Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, United States. |
| Jazyk: |
angličtina |
| Zdroj: |
The journal of physical chemistry letters [J Phys Chem Lett] 2022 Oct 13; Vol. 13 (40), pp. 9534-9538. Date of Electronic Publication: 2022 Oct 06. |
| DOI: |
10.1021/acs.jpclett.2c02292 |
| Abstrakt: |
The ability to detect and characterize multiple secondary structures or polymorphs within peptide and protein aggregates is crucial to treatment and prevention of amyloidogenic diseases, production of novel biomaterials, and many other applications. Here we report a label-free method to distinguish multiple β-sheet configurations within a single peptide aggregate using two-dimensional infrared spectroscopy. By calculating the transition dipole strength (TDS) spectrum from the ratio of linear and two-dimensional signals, we can extract maximum TDS values which provide higher sensitivity to vibrational coupling, and thus specifics of protein structure, than vibrational frequency alone. TDS spectra of AcKFE8 aggregates reveal two distinct β-sheet structures within fibers that appear homogeneous by other techniques. Furthermore, TDS spectra taken during early stages of aggregation show additional peaks that may indicate the presence of more weakly coupled β-sheet structures. These results demonstrate a unique and powerful spectroscopic method capable of distinguishing multiple oligomeric and polymorphic motifs throughout the aggregation using only native vibrational modes. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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