Low-temperature optical properties and pigment organization of the B875 light-harvesting bacteriochlorophyll-protein complex of purple photosynthetic bacteria

Kramer, Herman J. M.; Pennoyer, Jeffrey D.; Grondelle, Rienk van; Westerhuis, Willem H.J.; Niederman, Robert A.; Amesz, J.

doi:10.1016/0005-2728(84)90204-4

Cited by 131 publications

(82 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is clear that these kinetics and absorbance differences cannot be due entirely to BChl 875, but in addition, reflect a fast energy transfer from BChl 875 to a redshifted pigment. Previous work [7][8][9][10] has strongly suggested the presence of such a pigment, designated B896 [7]. Thus, we assign the fast component, rf = 15 + 5 ps, to energy transfer from BChl 875 to BChl 896 and the slow decay, rs = 650 _ 50 ps, to deactivation of BChl 896", decoupled completely from its energy acceptor, the reaction centers.…”

Section: Resultsmentioning

confidence: 85%

“…Fluorescence polarization at 4 K of the isolated B875 complex [7] was interpreted in terms of the existence of such an antenna pigment. Picosecond fluorescence streak-camera measurements of Rhodospirillum rubrum at 77 K displayed non-exponential fluorescence decay, which was also attributed to inhomogeneity of the B880 antenna [8].…”

Section: Introductionmentioning

confidence: 99%

“…Recent picosecond absorption recovery measurements on chromatophore preparations of Rs. rubrum and Rhodobacter sphaeroides at room temperature [9] Correspondence address: V. Sundstr6m, Department of Physical Chemistry, University of Ume~t, S-901 87 Ume6, Sweden and at 77 K [10] yielded conclusive evidence for the existence of a highly red-shifted antenna component, designated as B896 [7], in both these species.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Energy transfer within the isolated B875 light‐harvesting pigment‐protein complex of Rhodobacter sphaeroides at 77 K studied by picosecond absorption spectroscopy

et al. 1988

View full text Add to dashboard Cite

The energy transfer dynamics at 77 K within detergent solubilized and purified preparations of the B875 pigment-protein complex of Rhodobacter sphaeroides have been investigated by picosecond absorption spectroscopy. Isotropic absorption recovery and decay of induced absorption anisotropy provide clear evidence that B875 is inhomogeneous in these preparations. We interpret the results as fast (r = 15 + 5 ps) energy transfer from the major BChl 875 pigments to a minor pigment pool, B896. The excited state of B896 decays with a time constant of 650 + 50 ps. We suggest that B896 is intrinsic to B875 complexes and exists in a highly organized state, close to the reaction center. In the intact membrane, B896 may concentrate excitation energy in the vicinity of the reaction center special pair, thereby increasing the efficiency of the final energy transfer step.Antenna bacteriochlorophyll-protein complex; Bacterial photosynthesis; Energy transfer; (Rhodobacter sphaeriodes)

show abstract

Section: Resultsmentioning

confidence: 85%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Energy transfer within the isolated B875 light‐harvesting pigment‐protein complex of Rhodobacter sphaeroides at 77 K studied by picosecond absorption spectroscopy

et al. 1988

View full text Add to dashboard Cite

show abstract

“…For instance, the organization and relative orientation of the chromophores ͑bacteria chlo-rophylls a and b͒ in the bacterial light-harvesting complex LH 2 was determined using a combination of CD and linearly polarized spectroscopies. 28 In addition, experimental spectra have been analyzed using a framework of exciton theory, resulting in a detailed understanding of the optical properties of these systems. 29,30 CD spectroscopy on LEPs has also been used in a few cases.…”

Section: Introductionmentioning

confidence: 99%

Polarized optical spectroscopy applied to investigate two poly(phenylene-vinylene) polymers with different side chain structures

Pålsson

Vaughan

Monkman

2006

The Journal of Chemical Physics

View full text Add to dashboard Cite

Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-pro t purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. Two related poly͑phenylene-vinylene͒ ͑PPV͒ light-emitting polymers have been investigated by means of polarized optical spectroscopy. The purpose of the investigation was to investigate the nature of the interactions in thin films and to examine what impact the difference in side chain structure and molecular weight in poly͑2Ј-methoxy-5-2-ethyl-hexoxy͒-1,4-phenylene vinylene ͑MEH-PPV͒ and poly͑2-͑3Ј ,7Ј-dimethyloctyloxy͒-5-methoxy-1,4-phenylene-vinylene͒ ͑OC 1 C 10 -PPV͒ has on the electronic and optical properties of the two polymers. Aligning the polymers by dispersing them in anisotropic solvents and stretched films shows that the side chains have an impact on the relative orientations of the transition dipole moments. In anisotropic solvents the linear dichroism is larger for MEH-PPV than for the related polymer OC 1 C 10 -PPV, while in stretched films the opposite situation prevails. A lower polarization of the luminescence from OC 1 C 10 -PPV, relative to MEH-PPV, was also obtained independent of alignment medium used. The data therefore suggest that while mechanical stretching may align the OC 1 C 10 -PPV to a greater degree, the emitting species is distinct from the absorbing species. The circular dichroism ͑CD͒ spectra of both polymers undergo dramatic changes when the liquid phase and the solid state ͑film͒ are compared. The solution CD spectra shows no evidence of interchain interactions; instead the spectra of both systems indicate a helical conformation of the polymers. The CD spectra of films are dramatically different with the strong Cotton effect being observed. This points to the formation of an aggregate in the film, with an associated ground state interaction, an interchain species such as a physical dimer, or a more complex higher aggregate.

show abstract

“…Since the two organisms are often found to have very similar photosynthetic systems, these disparate results were unexpected. One possible explanation was that the R. sphaeroides mutant might still contain low levels of the B880 complex, perhaps the 15% identified by Kramer et al [5] as being closest to the reaction center. Meinhardt et al [3] did not present low temperature spectra of their mutant, nor the results of polyacrylamide gel electrophoresis, and it was possible that the spectrum of the B800-850 complex might obscure low levels of B880 in room temperature spectra.…”

Section: Introductionmentioning

confidence: 99%

On the role of the light‐harvesting B880 in the correct insertion of the reaction center of Rhodobacter capsulatus and Rhodobacter sphaeroides

et al. 1987

View full text Add to dashboard Cite

The purple, non-sulfur photosynthetic bacteria Rhodobacter capsulatus and Rhodobacter sphaeroides have two types of pigment-protein complexes that absorb incident light and funnel it to the photochemical reaction center. One of these, B880, is present at an essentially constant ratio to the reaction center, while the abundance of the other, B800-850, varies with growth conditions. Independent work in our two laboratories has indicated that while the absence of B800-850 permits photosynthetic growth in both organisms, the lack of B880 produces a different phenotype in the two species. Thus R. sphaeroides is still photosynthetically competent when it lacks this complex, while R. eapsulatus is not. This unanticipated difference in what appear to be very closely related organisms has caused us to reexamine the properties of the two mutants simultaneously, under identical conditions. We find that the original descriptions are indeed correct; the reaction center of R. capsulatus is not correctly inserted into the photosynthetic membrane in the absence of B880, while that of R. sphaeroides is.Reaction center insertion; Pigment-protein complex; (Rhodobacter)

show abstract

Low-temperature optical properties and pigment organization of the B875 light-harvesting bacteriochlorophyll-protein complex of purple photosynthetic bacteria

Cited by 131 publications

References 18 publications

Energy transfer within the isolated B875 light‐harvesting pigment‐protein complex of Rhodobacter sphaeroides at 77 K studied by picosecond absorption spectroscopy

Energy transfer within the isolated B875 light‐harvesting pigment‐protein complex of Rhodobacter sphaeroides at 77 K studied by picosecond absorption spectroscopy

Polarized optical spectroscopy applied to investigate two poly(phenylene-vinylene) polymers with different side chain structures

On the role of the light‐harvesting B880 in the correct insertion of the reaction center of Rhodobacter capsulatus and Rhodobacter sphaeroides

Contact Info

Product

Resources

About