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Effect of Hydrated Ionic Liquid on Photocycle and Dynamics of Photoactive Yellow Protein.

ABSTRACT: The mechanism by which proteins are solvated in hydrated ionic liquids remains an open question. Herein, the photoexcitation dynamics of photoactive yellow protein dissolved in hydrated choline dihydrogen phosphate (Hy[ch][dhp]) were studied by transient absorption and transient grating spectroscopy. The photocyclic reaction of the protein in Hy[ch][dhp] was similar to that observed in the buffer solution, as confirmed by transient absorption spectroscopy. However, the structural change of the protein during the photocycle in Hy[ch][dhp] was found to be different from that observed in the buffer solution. The known change in the diffusion coefficient of the protein was apparently suppressed in high concentrations of [ch][dhp], plausibly due to stabilization of the secondary structure.

SUBMITTER: Umezaki U

PROVIDER: S-EPMC8348629 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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Effect of Hydrated Ionic Liquid on Photocycle and Dynamics of Photoactive Yellow Protein.

Umezaki Utana U Hatakenaka Miu M Onodera Kana K Mizutani Hiroto H Kim Suhyang S Nakasone Yusuke Y Terazima Masahide M Kimura Yoshifumi Y

Molecules (Basel, Switzerland) 20210728 15

The mechanism by which proteins are solvated in hydrated ionic liquids remains an open question. Herein, the photoexcitation dynamics of photoactive yellow protein dissolved in hydrated choline dihydrogen phosphate (Hy[ch][dhp]) were studied by transient absorption and transient grating spectroscopy. The photocyclic reaction of the protein in Hy[ch][dhp] was similar to that observed in the buffer solution, as confirmed by transient absorption spectroscopy. However, the structural change of the p ...[more]

PMID: 34361707

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