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Energy Transfer Observed in Live Cells Using Two-Dimensional Electronic Spectroscopy.

ABSTRACT: Two-dimensional electronic spectroscopy (2DES) elucidates electronic structure and dynamics on a femtosecond time scale and has proven to be an incisive tool for probing congested linear spectra of biological systems. However, samples that scatter light intensely frustrate 2DES analysis, necessitating the use of isolated protein chromophore complexes when studying photosynthetic energy transfer processes. We present a method for conducting 2DES experiments that takes only seconds to acquire thousands of 2DES spectra and permits analysis of highly scattering samples, specifically whole cells of the purple bacterium Rhodobacter sphaeroides. These in vivo 2DES experiments reveal similar timescales for energy transfer within the antennae complex (light harvesting complex 2, LH2) both in the native photosynthetic membrane environment and in isolated detergent micelles.

SUBMITTER: Dahlberg PD

PROVIDER: S-EPMC3902138 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature

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Energy Transfer Observed in Live Cells Using Two-Dimensional Electronic Spectroscopy.

Dahlberg Peter D PD Fidler Andrew F AF Caram Justin R JR Long Phillip D PD Engel Gregory S GS

The journal of physical chemistry letters 20131001 21

Two-dimensional electronic spectroscopy (2DES) elucidates electronic structure and dynamics on a femtosecond time scale and has proven to be an incisive tool for probing congested linear spectra of biological systems. However, samples that scatter light intensely frustrate 2DES analysis, necessitating the use of isolated protein chromophore complexes when studying photosynthetic energy transfer processes. We present a method for conducting 2DES experiments that takes only seconds to acquire thou ...[more]

PMID: 24478821

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Energy Transfer Observed in Live Cells Using Two-Dimensional Electronic Spectroscopy.

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Energy Transfer Observed in Live Cells Using Two-Dimensional Electronic Spectroscopy.

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