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Updated: Jun 12, 2026

Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
Published on: February 7, 2022
When is the helix conformation restored after the reverse reaction of phototropin?
Yuki Kawaguchi1, Yusuke Nakasone, Kazunori Zikihara
1Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
Abstract:
Following the disruption of the covalent bond between the cysteine and flavin of Phot1LOV2-linker, the unfolded conformation of the linker folds with a time constant of 13 ms, which is considerably (approximately 10(4) times) slower than the helix formation rate measured for an alpha-helical polypeptide in solution.
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