Excited-State Energy Equilibration via Subpicosecond Energy Transfer within the Inhomogeneously Broadened Light-Harvesting Antenna of LH-1-Only <i>Rhodobacter sphaeroides</i> Mutants M2192 at Room Temperature and 4.2 K

Visser, Henk; Somsen, O. J. G.; Mourik, Frank van; Grondelle, Rienk van

doi:10.1021/jp960883+

Cited by 35 publications

(30 citation statements)

References 43 publications

(101 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The quantum yield can be calculated as reported in ( Sener et al, 2011 , 2010 ). Electronic excitation energy absorbed directly or indirectly (through carotenoids) by a BChl is rapidly shared between BChls within individual LH1 and LH2 light harvesting complexes ( Cory et al, 1998 ), forming, within about a ps, thermally equilibrated exciton states as established experimentally ( Visser et al, 1996 ; Jimenez et al, 1997 ; Valkunas et al, 2007 ) as well as computationally ( Strümpfer and Schulten, 2009 ; Strümpfer et al, 2012 ).…”

Section: Methodsmentioning

confidence: 97%

Overall energy conversion efficiency of a photosynthetic vesicle

Sener

Strümpfer

Singharoy

et al. 2016

eLife

174

View full text Add to dashboard Cite

The chromatophore of purple bacteria is an intracellular spherical vesicle that exists in numerous copies in the cell and that efficiently converts sunlight into ATP synthesis, operating typically under low light conditions. Building on an atomic-level structural model of a low-lightadapted chromatophore vesicle from Rhodobacter sphaeroides, we investigate the cooperation between more than a hundred protein complexes in the vesicle. The steady-state ATP production rate as a function of incident light intensity is determined after identifying quinol turnover at the cytochrome bc 1 complex (cytbc 1 ) as rate limiting and assuming that the quinone/quinol pool of about 900 molecules acts in a quasi-stationary state. For an illumination condition equivalent to 1% of full sunlight, the vesicle exhibits an ATP production rate of 82 ATP molecules/s. The energy conversion efficiency of ATP synthesis at illuminations corresponding to 1%-5% of full sunlight is calculated to be 0.12-0.04, respectively. The vesicle stoichiometry, evolutionarily adapted to the low light intensities in the habitat of purple bacteria, is suboptimal for steady-state ATP turnover for the benefit of protection against over-illumination.

show abstract

Section: Methodsmentioning

confidence: 97%

Overall energy conversion efficiency of a photosynthetic vesicle

Sener

Strümpfer

Singharoy

et al. 2016

eLife

174

View full text Add to dashboard Cite

show abstract

“…Similar biexponential time scales are noted in spectroscopic experiments for LH2 15,18,50,51 as well as LH1. 52,53 The steady-state populations at t = 5 ps are shown in Fig. 5 along with the populations expected from Boltzmann distributed exciton states.…”

Section: A Dynamics Of a Single B850 Ringmentioning

confidence: 99%

Light harvesting complex II B850 excitation dynamics

Strümpfer¹,

Schulten²

2009

The Journal of Chemical Physics

153

258

View full text Add to dashboard Cite

The dynamics of excitation energy transfer within the B850 ring of light harvesting complex 2 from Rhodobacter sphaeroides and between neighboring B850 rings is investigated by means of dissipative quantum mechanics. The assumption of Boltzmann populated donor states for the calculation of intercomplex excitation transfer rates by generalized Förster theory is shown to give accurate results since intracomplex exciton relaxation to near-Boltzmann population exciton states occurs within a few picoseconds. The primary channels of exciton transfer between B850 rings are found to be the five lowest-lying exciton states, with non-850 nm exciton states making significant contributions to the total transfer rate.

show abstract

“…Recent single-molecule experiments on LH-II indicate that at 1.2 K the excitation is to a large extent delocalized [50] over the ring. However, there are indications that in LH-I, static inhomogeneity becomes more significant at room temperature [51], and might, thus, lead to delocalization of excitons on a fewer number of BChls.…”

Section: Back-transfer Ratesmentioning

confidence: 99%

Excitation energy trapping by the reaction center ofRhodobacter Sphaeroides

Damjanovi

Ritz

Schulten

2000

Int. J. Quant. Chem.

View full text Add to dashboard Cite

The excitation energy transfer between light-harvesting complex I (LH-I)and the photosynthetic reaction center (RC) of the purple bacterium Rhodobacter (Rb.) sphaeroides is investigated on the basis of the atomic level structures of the two proteins, assuming a ring-shaped model for LH-I. Rates of excitation energy transfer are calculated, based on Förster theory. The LH-I and RC electronic excitations are described through effective Hamiltonians established previously, with parameters derived from quantum chemistry calculations by Cory and co-workers. We also present an effective Hamiltonian description with parameters based on spectroscopic properties. We study two extreme models of LH-I excitations: electronic excitations delocalized over the entire LH-I ring and excitations localized on single bacteriochlorophylls. The role of accessory bacteriochlorophylls in bridging the excitation energy transfer is investigated. The rates of back-transfer, i.e., RC → LH-I excitation energy transfer, are determined, too.

show abstract

Excited-State Energy Equilibration via Subpicosecond Energy Transfer within the Inhomogeneously Broadened Light-Harvesting Antenna of LH-1-Only Rhodobacter sphaeroides Mutants M2192 at Room Temperature and 4.2 K

Cited by 35 publications

References 43 publications

Overall energy conversion efficiency of a photosynthetic vesicle

Overall energy conversion efficiency of a photosynthetic vesicle

Light harvesting complex II B850 excitation dynamics

Excitation energy trapping by the reaction center ofRhodobacter Sphaeroides

Contact Info

Product

Resources

About