Modeling study of non-line-narrowed hole-burned spectra in weakly coupled dimers and multi-chromophoric molecular assemblies

Reppert, Mike; Naibo, Virginia; Jankowiak, Ryszard

doi:10.1016/j.chemphys.2009.10.013

Cited by 10 publications

(24 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Since coupling matrix elements between the two dimers are very small compared with reorganization energy (~20 cm −1 < ~60 cm −1 ) , we first consider two Chl dimers possessing identical SDFs that are connected by slow EET (for more details on uncorrelated EET see refs ). In this model, in a given tetramer, one or another dimer can be lower in energy (due to disorder) and their energies are independent.…”

Section: Discussionmentioning

confidence: 99%

New Insight into the Water‐Soluble Chlorophyll‐Binding Protein from Lepidium virginicum

Kell

Bednarczyk

Acharya

et al. 2016

Photochem & Photobiology

Self Cite

View full text Add to dashboard Cite

This study describes new recombinant water-soluble chlorophyll (Chl)-binding proteins (WSCP) from Lepidium virginicum (LvWSCP). This complex binds four Chls (i.e. two dimers of Chls) per protein tetramer. We show that absorption, emission, hole-burned (HB) spectra and the shape of the zero-phonon hole (ZPH) action spectrum are consistent with the presence of uncorrelated excitation energy transfer between two Chl dimers. Thus, there is no need to include slow protein relaxation within the lowest excited state (as suggested in a previous analysis of cauliflower WSCP [Schmitt, F.-J. et al. (2008) J. Phys. Chem. B, 112, 13951; Pieper, J. et al. (2011) J. Phys. Chem. B, 115, 4053]) in order to explain the large shift observed between the maxima of the ZPH action and emission spectra. Experimental evidence is provided which shows that electron exchange between lowest energy Chls and the protein may occur, i.e. electrons can be trapped at low temperature by nearby aromatic amino acids. The latter explains the shape of nonresonant HB spectra (i.e. the absence of antihole), demonstrating that the hole-burning process in LvWSCP is largely photochemical in nature, though a small contribution from nonphotochemical hole burning (in resonant holes) is also observed.

show abstract

Section: Discussionmentioning

confidence: 99%

New Insight into the Water‐Soluble Chlorophyll‐Binding Protein from Lepidium virginicum

Kell

Bednarczyk

Acharya

et al. 2016

Photochem & Photobiology

Self Cite

View full text Add to dashboard Cite

show abstract

“…3 and S3) are due to the photophysical effects referred to as non-resonant holeburning [61][62][63]. The changes reverse rapidly upon warming the sample abovẽ 30 K, so the spectra at higher temperatures are unaffected by the process (Fig.…”

Section: Spectral Changes Arising From Low-temperature Illuminationmentioning

confidence: 94%

The lowest-energy chlorophyll of photosystem II is adjacent to the peripheral antenna: Emitting states of CP47 assigned via circularly polarized luminescence

Hall

Renger

Müh

et al. 2016

Biochimica et Biophysica Acta (BBA) - Bioenergetics

View full text Add to dashboard Cite

The identification of low-energy chlorophyll pigments in photosystem II (PSII) is critical to our understanding of the kinetics and mechanism of this important enzyme. We report parallel circular dichroism (CD) and circularly polarized luminescence (CPL) measurements at liquid helium temperatures of the proximal antenna protein CP47. This assembly hosts the lowest-energy chlorophylls in PSII, responsible for the well-known "F695" fluorescence band of thylakoids and PSII core complexes. Our new spectra enable a clear identification of the lowest-energy exciton state of CP47. This state exhibits a small but measurable excitonic delocalization, as predicated by its CD and CPL. Using structure-based simulations incorporating the new spectra, we propose a revised set of site energies for the 16 chlorophylls of CP47. The significant difference from previous analyses is that the lowest-energy pigment is assigned as Chl 612 (alternately numbered Chl 11). The new assignment is readily reconciled with the large number of experimental observations in the literature, while the most common previous assignment for the lowest energy pigment, Chl 627(29), is shown to be inconsistent with CD and CPL results. Chl 612(11) is near the peripheral light-harvesting system in higher plants, in a lumen-exposed region of the thylakoid membrane. The low-energy pigment is also near a recently proposed binding site of the PsbS protein. This result consequently has significant implications for our understanding of the kinetics and regulation of energy transfer in PSII.

show abstract

“…22 There are two components for pigment i. One component is a trap state L i (ω), which is already at the lowest energy and is not capable to transfer energy; the other component allows EET to other pigments, and is labeled with U i (ω).…”

Section: Derivation Of Analytical Formulas To Calculate Fln Spectmentioning

confidence: 99%

“…One possible way to ease the calculation processes of FLN spectra (in the presence of EET) is to develop analytical formulas for weak coupling conditions, including only the ef-fects of energy transfer between different chromophores in the complex and ignoring explicit coupling effects. Under weak inter-pigment coupling and weak el-ph coupling conditions, where uncorrelated EET and efficient Förster energy transfer between pigments can take place, Reppert et al 22 developed analytical formulas to describe the process of uncorrelated EET and to model nonphotochemical hole-burned (NPHB) spectra. In this work, the latter model 22 is extended to simulate resonant FLN spectra in the presence of EET (modeling of FLN spectra will be reported elsewhere).…”

Section: Introductionmentioning

confidence: 99%

“…Under weak inter-pigment coupling and weak el-ph coupling conditions, where uncorrelated EET and efficient Förster energy transfer between pigments can take place, Reppert et al 22 developed analytical formulas to describe the process of uncorrelated EET and to model nonphotochemical hole-burned (NPHB) spectra. In this work, the latter model 22 is extended to simulate resonant FLN spectra in the presence of EET (modeling of FLN spectra will be reported elsewhere). We show below that the analytical formulas developed to describe FLN spectra provide a very good approximation of both SCM and RA type calculations, assuming that both excitonic and el-ph couplings are weak.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Modeling of fluorescence line-narrowed spectra in weakly coupled dimers in the presence of excitation energy transfer

Lin

Reppert

Feng

et al. 2014

The Journal of Chemical Physics

Self Cite

View full text Add to dashboard Cite

This work describes simple analytical formulas to describe the fluorescence line-narrowed (FLN) spectra of weakly coupled chromophores in the presence of excitation energy transfer (EET). Modeling studies for dimer systems (assuming low fluence and weak coupling) show that the FLN spectra (including absorption and emission spectra) calculated for various dimers using our model are in good agreement with spectra calculated by: (i) the simple convolution method and (ii) the more rigorous treatment using the Redfield approach [T. Renger and R. A. Marcus, J. Chem. Phys. 116, 9997 (2002)]. The calculated FLN spectra in the presence of EET of all three approaches are very similar. We argue that our approach provides a simplified and computationally more efficient description of FLN spectra in the presence of EET. This method also has been applied to FLN spectra obtained for the CP47 antenna complex of Photosystem II reported by Neupane et al. [J. Am. Chem. Soc. 132, 4214 (2010)], which indicated the presence of uncorrelated EET between pigments contributing to the two lowest energy (overlapping) exciton states, each mostly localized on a single chromophore. Calculated and experimental FLN spectra for CP47 complex show very good qualitative agreement.

show abstract

Modeling study of non-line-narrowed hole-burned spectra in weakly coupled dimers and multi-chromophoric molecular assemblies

Cited by 10 publications

References 28 publications

New Insight into the Water‐Soluble Chlorophyll‐Binding Protein from Lepidium virginicum

New Insight into the Water‐Soluble Chlorophyll‐Binding Protein from Lepidium virginicum

The lowest-energy chlorophyll of photosystem II is adjacent to the peripheral antenna: Emitting states of CP47 assigned via circularly polarized luminescence

Modeling of fluorescence line-narrowed spectra in weakly coupled dimers in the presence of excitation energy transfer

Contact Info

Product

Resources

About