A Photoinduced Persistent Structural Transformation of the Special Pair of a Bacterial Reaction Center

Reddy, N. R. S.; Kolaczkowski, Stephen V.; Small, Gerald J.

doi:10.1126/science.260.5104.68

Cited by 50 publications

(50 citation statements)

References 43 publications

(23 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(C) The same asA, but the width of the one-vibration profile is 10 cm-'. contribution seems to be negligible because as it was shown by Reddy et al (1993) that inhomogeneous broadening originates in the RC special pair primarily from statistical fluctuations in protein structure around the special pair rather than from a distribution of structures for the special pair itself.…”

Section: Discussionmentioning

confidence: 95%

Energy transfer in the inhomogeneously broadened core antenna of purple bacteria: a simultaneous fit of low-intensity picosecond absorption and fluorescence kinetics

Pullerits¹,

Visscher²,

Hess³

et al. 1994

Biophysical Journal

View full text Add to dashboard Cite

The excited state decay kinetics of chromatophores of the purple photosynthetic bacterium Rhodospirillum rubrum have been recorded at 77 K using picosecond absorption difference spectroscopy under strict annihilation free conditions. The kinetics are shown to be strongly detection wavelength dependent. A simultaneous kinetic modeling of these experiments together with earlier fluorescence kinetics by numerical integration of the appropriate master equation is performed. This model, which accounts for the spectral inhomogeneity of the core light-harvesting antenna of photosynthetic purple bacteria, reveals three qualitatively distinct stages of excitation transfer with different time scales. At first a fast transfer to a local energy minimum takes place (approximately 1 ps). This is followed by a much slower transfer between different energy minima (10-30 ps). The third component corresponds to the excitation transfer to the reaction center, which depends on its state (60 and 200 ps for open and closed, respectively) and seems also to be the bottleneck in the overall trapping time. An acceptable correspondence between theoretical and experimental decay kinetics is achieved at 77 K and at room temperature by assuming that the width of the inhomogeneous broadening is 10-15 nm and the mean residence time of the excitation in the antenna lattice site is 2-3 ps.

show abstract

Section: Discussionmentioning

confidence: 95%

Energy transfer in the inhomogeneously broadened core antenna of purple bacteria: a simultaneous fit of low-intensity picosecond absorption and fluorescence kinetics

Pullerits¹,

Visscher²,

Hess³

et al. 1994

Biophysical Journal

View full text Add to dashboard Cite

show abstract

“…Small's group has extensively performed hole-burning (HB) measurements on mutant and chemically altered RCs of Rb. Sphaeroides [44,45,[48][49][50]. Their results have revealed low-frequency modes that make important contribution to optical features such as the bandwidth of absorption line-shape, as well as to the rate constant of the ET of the RCs.…”

Section: Introductionmentioning

confidence: 96%

Ultrafast Dynamics and Spectroscopy of Bacterial Photosynthetic Reaction Centers

Lin¹,

Chang²,

Liang³

et al. 2002

Advances in Chemical Physics

117

View full text Add to dashboard Cite

“…These modes, arising from the solvent and low-energy protein vibrations, induce thermal fluctuations of onsite energies which in turn drive transitions between energetically close excitonic states. Secondly, spectroscopy studies [5][6][7][8][9][10][11][12][13] also reveal the active participation of specific vibrational modes during excitation dynamics, often described as peaks in the spectral density characterising excitonphonon interactions. Vibrations with lower frequencies may arise from inter-molecular coupling between pigments and the local protein environment 11 while peaks at high energies originate mostly from intramolecular vibrations that give rise to vibronic transitions 15,16 .…”

Section: Introductionmentioning

confidence: 99%

The fundamental role of quantized vibrations in coherent light harvesting by cryptophyte algae

Kolli¹,

O’Reilly²,

Scholes³

et al. 2012

The Journal of Chemical Physics

214

298

View full text Add to dashboard Cite

The influence of fast vibrations on energy transfer and conversion in natural molecular aggregates is an issue of central interest. This article shows the important role of high-energy quantized vibrations and their non-equilibrium dynamics for energy transfer in photosynthetic systems with highly localized excitonic states. We consider the cryptophyte antennae protein phycoerythrin 545 and show that coupling to quantized vibrations, which are quasi-resonant with excitonic transitions is fundamental for biological function as it generates non-cascaded transport with rapid and wider spatial distribution of excitation energy. Our work also indicates that the non-equilibrium dynamics of such vibrations can manifest itself in ultrafast beating of both excitonic populations and coherences at room temperature, with time scales in agreement with those reported in experiments. Moreover, we show that mechanisms supporting coherent excitonic dynamics assist coupling to selected modes that channel energy to preferential sites in the complex. We therefore argue that, in the presence of strong coupling between electronic excitations and quantized vibrations, a concrete and important advantage of quantum coherent dynamics is precisely to tune resonances that promote fast and effective energy distribution.

show abstract

A Photoinduced Persistent Structural Transformation of the Special Pair of a Bacterial Reaction Center

Cited by 50 publications

References 43 publications

Energy transfer in the inhomogeneously broadened core antenna of purple bacteria: a simultaneous fit of low-intensity picosecond absorption and fluorescence kinetics

Energy transfer in the inhomogeneously broadened core antenna of purple bacteria: a simultaneous fit of low-intensity picosecond absorption and fluorescence kinetics

Ultrafast Dynamics and Spectroscopy of Bacterial Photosynthetic Reaction Centers

The fundamental role of quantized vibrations in coherent light harvesting by cryptophyte algae

Contact Info

Product

Resources

About