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arXiv · 2611.06602

Unraveling Primary Energy Conversion Dynamics in Intact Cells of Gemmatimonas groenlandica

Julian Lüttig·Ajeet Kumar·Maurice Schenker·Alastair T. Gardiner·Michal Koblížek·Donatas Zigmantas·Jennifer P. Ogilvie
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Abstract

Photosynthetic bacteria have evolved specialized light-harvesting structures to efficiently capture sunlight. Here, we investigate the ultrafast dynamics in intact cells of Gemmatimonas groenlandica, featuring unique double-ring LHh-LH1 photosynthetic complexes containing bacteriochlorophyll a. Two-dimensional electronic spectroscopy with lock-in detection allows us to directly observe primary energy-conversion processes, from excitation-energy transfer within the antenna system to the formation of a charge-separated state in the reaction center, taking place on 50 ps time scale. Through comparison with Rhodospirillum rubrum, which lacks the outer antenna ring, we use a combination of global analysis and nodal/center line slope analyses to resolve LHh-LH1 excitation energy transfer which occurs on a ~1-2 ps timescale in Gemmatimonas groenlandica.

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Julian Lüttig, Ajeet Kumar, Maurice Schenker, Alastair T. Gardiner, Michal Koblížek, Donatas Zigmantas, Jennifer P. Ogilvie. 2026-11-04. Unraveling Primary Energy Conversion Dynamics in Intact Cells of Gemmatimonas groenlandica. https://arxiv.org/abs/2611.06602

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