Application study of infrared free-electron lasers towards the development of amyloidosis therapy
open access.
| Veröffentlicht in: | Journal of synchrotron radiation. - 1994. - 29(2022), Pt 5 vom: 01. Sept., Seite 1133-1140 |
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| 1. Verfasser: | |
| Weitere Verfasser: | , , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2022
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| Zugriff auf das übergeordnete Werk: | Journal of synchrotron radiation |
| Schlagworte: | Journal Article amyloid fibril amyloidosis infrared free-electron laser β2-microglobulin Amides Amyloid Peptides |
| Zusammenfassung: | open access. Amyloidosis is known to be caused by the deposition of amyloid fibrils into various biological tissues; effective treatments for the disease are little established today. An infrared free-electron laser (IR-FEL) is an accelerator-based picosecond-pulse laser having tunable infrared wavelengths. In the current study, the irradiation effect of an IR-FEL was tested on an 11-residue peptide (NFLNCYVSGFH) fibril from β2-microglobulin (β2M) with the aim of applying IR-FELs to amyloidosis therapy. Infrared microspectroscopy (IRM) and scanning electron microscopy showed that a fibril of β2M peptide was clearly dissociated by IR-FEL at 6.1 µm (amide I) accompanied by a decrease of the β-sheet and an increase of the α-helix. No dissociative process was recognized at 6.5 µm (amide II) as well as at 5.0 µm (non-specific wavelength). Equilibrium molecular dynamics simulations indicated that the α-helix can exist stably and the probability of forming interchain hydrogen bonds associated with the internal asparagine residue (N4) is notably reduced compared with other amino acids after the β-sheet is dissociated by amide I specific irradiation. This result implies that N4 plays a key role for recombination of hydrogen bonds in the dissociation of the β2M fibril. In addition, the β-sheet was disrupted at temperatures higher than 340 K while the α-helix did not appear even though the fibril was heated up to 363 K as revealed by IRM. The current study gives solid evidence for the laser-mediated conversion from β-sheet to α-helix in amyloid fibrils at the molecular level |
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| Beschreibung: | Date Completed 09.09.2022 Date Revised 04.10.2022 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1600-5775 |
| DOI: | 10.1107/S1600577522007330 |