Redox driven B12-ligand switch drives CarH photoresponse.
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ABSTRACT:
SUBMITTER: Poddar H
PROVIDER: S-EPMC10442372 | biostudies-literature | 2023 Aug
REPOSITORIES: biostudies-literature
Publications
Redox driven B<sub>12</sub>-ligand switch drives CarH photoresponse.
Poddar Harshwardhan H Rios-Santacruz Ronald R Heyes Derren J DJ Shanmugam Muralidharan M Brookfield Adam A Johannissen Linus O LO Levy Colin W CW Jeffreys Laura N LN Zhang Shaowei S Sakuma Michiyo M Colletier Jacques-Philippe JP Hay Sam S Schirò Giorgio G Weik Martin M Scrutton Nigel S NS Leys David D
Nature communications 20230821 1
CarH is a coenzyme B<sub>12</sub>-dependent photoreceptor involved in regulating carotenoid biosynthesis. How light-triggered cleavage of the B<sub>12</sub> Co-C bond culminates in CarH tetramer dissociation to initiate transcription remains unclear. Here, a series of crystal structures of the CarH B<sub>12</sub>-binding domain after illumination suggest formation of unforeseen intermediate states prior to tetramer dissociation. Unexpectedly, in the absence of oxygen, Co-C bond cleavage is follo ...[more]
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