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Light and heat control over secondary structure and amyloid-like fiber formation in an overcrowded-alkene-modified Trp zipper.

ABSTRACT: The external photocontrol over peptide folding, by the incorporation of molecular photoswitches into their structure, provides a powerful tool to study biological processes. However, it is limited so far to switches that exhibit only a rather limited geometrical change upon photoisomerization and that show thermal instability of the photoisomer. Here we describe the use of an overcrowded alkene photoswitch to control a model ?-hairpin peptide. This photoresponsive unit undergoes a large conformational change and has two thermally stable isomers which has major influence on the secondary structure and the aggregation of the peptide, permitting the phototriggered formation of amyloid-like fibrils.

SUBMITTER: Poloni C

PROVIDER: S-EPMC5512536 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature

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Light and heat control over secondary structure and amyloid-like fiber formation in an overcrowded-alkene-modified Trp zipper.

Poloni Claudia C Stuart Marc C A MCA van der Meulen Pieter P Szymanski Wiktor W Feringa Ben L BL

Chemical science 20150923 12

The external photocontrol over peptide folding, by the incorporation of molecular photoswitches into their structure, provides a powerful tool to study biological processes. However, it is limited so far to switches that exhibit only a rather limited geometrical change upon photoisomerization and that show thermal instability of the photoisomer. Here we describe the use of an overcrowded alkene photoswitch to control a model β-hairpin peptide. This photoresponsive unit undergoes a large conforma ...[more]

PMID: 28757990

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