Light-harvesting system 2 (LH2) executes the primary processes of photosynthesis in purple bacteria; photon absorption and energy transportation to the reaction centre. A detailed mechanistic insight into these operations is obscured by the complexity of the light-harvesting systems, particularly by the chromophore-environment interaction. In this work, we focus on the effects of the protein residues that are ligated to the bacteriochlorophylls (BChls), and construct potential energy surfaces of the ground and first optically-excited state for the various BChl-residue systems, where we in each case consider two degrees of freedom in the intermolecular region. We find that the excitation energies are only slightly affected by the considered modes. In addition, we see that axial ligands and hydrogen-bonded residues have opposite effects on both excitation energies and oscillator strengths, by comparing to the isolated BChls. Our results indicate that only a small part of the chromophore-environment interaction can be associated with the intermolecular region between a BChl and an adjacent residue, but that it may be possible to selectively raise or lower the excitation energy at the axial and planar residue positions, respectively.
Anda, A., DE VICO, L., Hansen, T. (2017). Intermolecular Modes Between LH2 Bacteriochlorophylls and Protein Residues; the Effect on the Excitation Energies. JOURNAL OF PHYSICAL CHEMISTRY. B, CONDENSED MATTER, MATERIALS, SURFACES, INTERFACES & BIOPHYSICAL, 121(22), 5499-5508 [10.1021/acs.jpcb.7b02071].
Intermolecular Modes Between LH2 Bacteriochlorophylls and Protein Residues; the Effect on the Excitation Energies
DE VICO, LUCA;
2017-01-01
Abstract
Light-harvesting system 2 (LH2) executes the primary processes of photosynthesis in purple bacteria; photon absorption and energy transportation to the reaction centre. A detailed mechanistic insight into these operations is obscured by the complexity of the light-harvesting systems, particularly by the chromophore-environment interaction. In this work, we focus on the effects of the protein residues that are ligated to the bacteriochlorophylls (BChls), and construct potential energy surfaces of the ground and first optically-excited state for the various BChl-residue systems, where we in each case consider two degrees of freedom in the intermolecular region. We find that the excitation energies are only slightly affected by the considered modes. In addition, we see that axial ligands and hydrogen-bonded residues have opposite effects on both excitation energies and oscillator strengths, by comparing to the isolated BChls. Our results indicate that only a small part of the chromophore-environment interaction can be associated with the intermolecular region between a BChl and an adjacent residue, but that it may be possible to selectively raise or lower the excitation energy at the axial and planar residue positions, respectively.File | Dimensione | Formato | |
---|---|---|---|
acs%2Ejpcb%2E7b02071.pdf
non disponibili
Descrizione: Articolo principale
Tipologia:
PDF editoriale
Licenza:
NON PUBBLICO - Accesso privato/ristretto
Dimensione
7.89 MB
Formato
Adobe PDF
|
7.89 MB | Adobe PDF | Visualizza/Apri Richiedi una copia |
DE VICO-Intermolecular Modes-PostPrint-3.pdf
accesso aperto
Descrizione: Accepted Manuscript
Tipologia:
Post-print
Licenza:
PUBBLICO - Pubblico con Copyright
Dimensione
8.5 MB
Formato
Adobe PDF
|
8.5 MB | Adobe PDF | Visualizza/Apri |
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
https://hdl.handle.net/11365/1007497