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Pump-Probe Circular Dichroism Spectroscopy of Cyanobacteriochrome TePixJ Yields: Insights into Its Photoconversion.

ABSTRACT: The bilin-containing photoreceptor TePixJ, a member of the cyanobacteriochrome (CBCR) family of phytochromes, switches between blue-light-absorbing and green-light-absorbing states in order to drive phototaxis in Thermosynechococcus elongatus. Its photoswitching process involves the formation of a thioether linkage between the C10 carbon of phycoviolobilin and the sidechain of Cys494 during the change in state from green-absorbing to blue-absorbing forms. Complex changes in the binding pocket propagate the signal to other domains for downstream signaling. Here, we report time-resolved circular dichroism experiments in addition to pump-probe absorption measurements for interpretation of the biophysical mechanism of the green-to-blue photoconversion process of this receptor.

SUBMITTER: Clinger JA

PROVIDER: S-EPMC8721879 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Pump-Probe Circular Dichroism Spectroscopy of Cyanobacteriochrome TePixJ Yields: Insights into Its Photoconversion.

Clinger Jonathan A JA Chen Eefei E Kliger David S DS Phillips George N GN

The journal of physical chemistry. B 20201223 1

The bilin-containing photoreceptor TePixJ, a member of the cyanobacteriochrome (CBCR) family of phytochromes, switches between blue-light-absorbing and green-light-absorbing states in order to drive phototaxis in <i>Thermosynechococcus elongatus</i>. Its photoswitching process involves the formation of a thioether linkage between the C10 carbon of phycoviolobilin and the sidechain of Cys494 during the change in state from green-absorbing to blue-absorbing forms. Complex changes in the binding po ...[more]

PMID: 33355472

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