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Magnetoreception of Photoactivated Cryptochrome 1 in Electrochemistry and Electron Transfer.

ABSTRACT: Cryptochromes are flavoproteins whose photochemistry is important for crucial functions associated with phototropism and circadian clocks. In this report, we, for the first time, observed a magnetic response of the cryptochrome 1 (CRY1) immobilized at a gold electrode with illumination of blue light. These results present the magnetic field-enhanced photoinduced electron transfer of CRY1 to the electrode by voltammetry, exhibiting magnetic responsive rate constant and electrical current changes. A mechanism of the electron transfer, which involves photoinduced radicals in the CRY, is sensitive to the weak magnetic field; and the long-lived free radical FAD•- is responsible for the detected electrochemical Faradaic current. As a photoreceptor, the finding of a 5.7% rate constant change in electron transfer corresponding to a 50 ?T magnetic field may be meaningful in regulation of magnetic field signaling and circadian clock function under an electromagnetic field.

SUBMITTER: Zeng Z

PROVIDER: S-EPMC6641772 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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Magnetoreception of Photoactivated Cryptochrome 1 in Electrochemistry and Electron Transfer.

Zeng Zheng Z Wei Jianjun J Liu Yiyang Y Zhang Wendi W Mabe Taylor T

ACS omega 20180501 5

Cryptochromes are flavoproteins whose photochemistry is important for crucial functions associated with phototropism and circadian clocks. In this report, we, for the first time, observed a magnetic response of the cryptochrome 1 (CRY1) immobilized at a gold electrode with illumination of blue light. These results present the magnetic field-enhanced photoinduced electron transfer of CRY1 to the electrode by voltammetry, exhibiting magnetic responsive rate constant and electrical current changes. ...[more]

PMID: 31458694

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