Autor: |
Mónica Gutiérrez-Salazar, Eduardo Santamaría-Aranda, Louise Schaar, Jesús Salgado, Diego Sampedro, Victor A. Lorenz-Fonfria |
Jazyk: |
angličtina |
Rok vydání: |
2021 |
Předmět: |
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Zdroj: |
iScience, Vol 24, Iss 7, Pp 102771- (2021) |
Druh dokumentu: |
article |
ISSN: |
2589-0042 |
DOI: |
10.1016/j.isci.2021.102771 |
Popis: |
Summary: The spontaneous insertion of helical transmembrane (TM) polypeptides into lipid bilayers is driven by three sequential equilibria: solution-to-membrane interface (MI) partition, unstructured-to-helical folding, and MI-to-TM helix insertion. A bottleneck for understanding these three steps is the lack of experimental approaches to perturb membrane-bound hydrophobic polypeptides out of equilibrium rapidly and reversibly. Here, we report on a 24-residues-long hydrophobic α-helical polypeptide, covalently coupled to an azobenzene photoswitch (KCALP-azo), which displays a light-controllable TM/MI equilibrium in hydrated lipid bilayers. FTIR spectroscopy reveals that trans KCALP-azo folds as a TM α-helix (TM topology). After trans-to-cis photoisomerization of the azobenzene moiety with UV light (reversed with blue light), the helical structure of KCALP-azo is maintained, but its helix tilt increased from 32 ± 5° to 79 ± 8°, indication of a reversible TM-to-MI transition. Further analysis indicates that this transition is incomplete, with cis KCALP-azo existing in a ∼90% TM and ∼10% MI mixture. |
Databáze: |
Directory of Open Access Journals |
Externí odkaz: |
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