How reduced excitonic coupling enhances light harvesting in the main photosynthetic antennae of diatoms.

ABSTRACT: Strong excitonic interactions are a key design strategy in photosynthetic light harvesting, expanding the spectral cross-section for light absorption and creating considerably faster and more robust excitation energy transfer. These molecular excitons are a direct result of exceptionally densely packed pigments in photosynthetic proteins. The main light-harvesting complexes of diatoms, known as fucoxanthin-chlorophyll proteins (FCPs), are an exception, displaying surprisingly weak excitonic coupling between their chlorophyll (Chl) a's, despite a high pigment density. Here, we show, using single-molecule spectroscopy, that the FCP complexes of Cyclotella meneghiniana switch frequently into stable, strongly emissive states shifted 4-10 nm toward the red. A few percent of isolat

SUBMITTER: Kruger TPJ 

PROVIDER: S-EPMC5748208 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature