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Insights into colour-tuning of chlorophyll optical response in green plants.

ABSTRACT: First-principles calculations within the framework of real-space time-dependent density functional theory have been performed for the complete chlorophyll (Chl) network of the light-harvesting complex from green plants, LHC-II. A local-dipole analysis method developed for this work has made possible the studies of the optical response of individual Chl molecules subjected to the influence of the remainder of the chromophore network. The spectra calculated using our real-space TDDFT method agree with previous suggestions that weak interaction with the protein microenvironment should produce only minor changes in the absorption spectrum of Chl chromophores in LHC-II. In addition, relative shifting of Chl absorption energies leads the stromal and lumenal sides of LHC-II to absorb in slightly different parts of the visible spectrum providing greater coverage of the available light frequencies. The site-specific alterations in Chl excitation energies support the existence of intrinsic energy transfer pathways within the LHC-II complex.

SUBMITTER: Jornet-Somoza J

PROVIDER: S-EPMC4598288 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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Insights into colour-tuning of chlorophyll optical response in green plants.

Jornet-Somoza Joaquim J Alberdi-Rodriguez Joseba J Milne Bruce F BF Andrade Xavier X Marques Miguel A L MA Nogueira Fernando F Oliveira Micael J T MJ Stewart James J P JJ Rubio Angel A

Physical chemistry chemical physics : PCCP 20151001 40

First-principles calculations within the framework of real-space time-dependent density functional theory have been performed for the complete chlorophyll (Chl) network of the light-harvesting complex from green plants, LHC-II. A local-dipole analysis method developed for this work has made possible the studies of the optical response of individual Chl molecules subjected to the influence of the remainder of the chromophore network. The spectra calculated using our real-space TDDFT method agree ...[more]

PMID: 26250099

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Insights into colour-tuning of chlorophyll optical response in green plants.

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Insights into colour-tuning of chlorophyll optical response in green plants.

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