Protein alpha helix — FTIR absorption peaks and assignments
These are the characteristic FTIR wavenumbers where Protein alpha helix tends to absorb, compiled from published literature and ranked by supporting evidence. Each assignment is traceable to a source (DOI) and cross-validated against our 130,000+ reference spectra and knowledge graph.
Backed by 8 cited sources
Characteristic FTIR peaks for Protein alpha helix
| Wavenumber (cm⁻¹) | Supporting facts | Cited sources | Top confidence |
|---|---|---|---|
| 1650 | 10 | 7 | 1.0 |
| 1655 | 5 | 3 | 0.9 |
| 1652 | 4 | 4 | 0.9 |
| 1653 | 4 | 1 | 0.9 |
| 1656 | 3 | 3 | 1.0 |
| 1654 | 3 | 3 | 0.95 |
| 1660 | 2 | 2 | 0.9 |
| 1651 | 2 | 2 | 0.9 |
| 1640 | 1 | 1 | 0.95 |
| 1664 | 1 | 1 | 0.95 |
| 1649 | 1 | 1 | 0.9 |
| 1637 | 1 | 1 | 0.9 |
| 1668 | 1 | 1 | 0.9 |
| 1657 | 1 | 1 | 0.9 |
| 1547 | 1 | 1 | 0.9 |
| 1550 | 1 | 1 | 0.9 |
| 1317 | 1 | 1 | 0.8 |
| 1339 | 1 | 1 | 0.8 |
| 934 | 1 | 1 | 0.8 |
| 1670 | 1 | 1 | 0.8 |
| 1659 | 1 | 1 | 0.8 |
| 1683 | 1 | 1 | 0.3 |
| 1663 | 1 | 1 | 0.3 |
| 1658 | 1 | 0 | 0.9 |
Literature behind these assignments
-
1656 cm⁻¹ confidence 1.0
“Text: 'amide I (1656 for cm-1 α-helix β-sheet)'”
Peris 等 - 2023 - Roadmap for Postnatal Brain Maturation Changes in DOI: 10.1021/acschemneuro.3c00237 -
1664 cm⁻¹ confidence 0.95
“Explicitly assigned: 'peak for 1664cm-1, α-helix'”
Stigsnaes 等 - 2007 - Characterisation and physical stability of PEGylat DOI: 10.1016/j.ijpharm.2006.09.002 -
1656 cm⁻¹ confidence 0.95
“Explicit assignment: 'α-helix at ca. 1656 cm-1'.”
Yu 等 - 2015 - Molecular basis of processing-induced changes in p DOI: 10.1016/j.saa.2015.06.050 -
1640 cm⁻¹ confidence 0.95
“Explicit assignment in text.”
Komorek 等 - 2021 - Adsorption and Conformation Behavior of Lysozyme o DOI: 10.3390/ijms22031322 -
1654 cm⁻¹ confidence 0.95
“Explicit assignment: 'Vibrational components of α-helices in the amide I region can be recognized at 1654 cm-1'”
Nedelkovski 等 - 2013 - Surface-Enhanced Infrared Absorption Spectroscopy DOI: 10.1021/jp4056347 -
1650 cm⁻¹ confidence 0.95
“Explicit assignment in text: 'α-helices at 1650 cm-1'”
Vorob'ev 等 - 2023 - Proteolysis of Micellar beta-Casein by Trypsin Se DOI: 10.3390/ijms24043874 -
1650 cm⁻¹ confidence 0.9
“Text: 'peak at 1650 cm-1 α-helix'”
Balazs 等 - 2014 - Protein structure is changed in psoriatic skin on DOI: 10.1016/j.microc.2014.07.003 -
1655 cm⁻¹ confidence 0.9
“Explicit assignment: 'α-helix (ca. 1,655 cm-1)'”
Damiran 和 Yu - 2011 - Molecular basis of structural makeup of hulless ba DOI: 10.3168/jds.2011-4564
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