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Wavelength-dependent photocycle activity of xanthorhodopsin in the visible region.

ABSTRACT: Xanthorhodopsin (xR) is a dual-chromophore proton-pump photosynthetic protein comprising one retinal Schiff base and one light-harvesting antenna salinixanthin (SX). The excitation wavelength-dependent transient population of the intermediate M demonstrates that the excitation of the retinal at 570 nm leads to the highest photocycle activity and the excitations of SX at 460 and 430 nm reduce the activity to ca. 37% relatively, suggesting an energy transfer pathway from the S₂ state of the SX to the S₁ state of the retinal and a quick internal vibrational relaxation in the S₂ state of SX prior to the energy transfer from SX to retinal.

SUBMITTER: Chiang HK

PROVIDER: S-EPMC5613640 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

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Wavelength-dependent photocycle activity of xanthorhodopsin in the visible region.

Chiang Han-Kuei HK Chu Li-Kang LK

Biochemistry and biophysics reports 20160721

Xanthorhodopsin (xR) is a dual-chromophore proton-pump photosynthetic protein comprising one retinal Schiff base and one light-harvesting antenna salinixanthin (SX). The excitation wavelength-dependent transient population of the intermediate M demonstrates that the excitation of the retinal at 570 nm leads to the highest photocycle activity and the excitations of SX at 460 and 430 nm reduce the activity to <i>ca.</i> 37% relatively, suggesting an energy transfer pathway from the S<sub>2</sub> s ...[more]

PMID: 28955925

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