Temperature dependence of the Qy resonance Raman spectra of bacteriochlorophylls, the primary electron donor, and bacteriopheophytins in the bacterial photosynthetic reaction center. 1997

N J Cherepy, and A P Shreve, and L J Moore, and S G Boxer, and R A Mathies
Department of Chemistry, University of California, Berkeley, California 94720, USA.

Qy-excited resonance Raman spectra of the accessory bacteriochlorophylls (B), the bacteriopheophytins (H), and the primary electron donor (P) in the bacterial photosynthetic reaction center (RC) of Rhodobacter sphaeroides have been obtained at 95 and 278 K. Frequency and intensity differences are observed in the low-frequency region of the P vibrational spectrum when the sample is cooled from 278 to 95 K. The B and H spectra exhibit minimal changes of frequencies and relative intensities as a function of temperature. The mode patterns in the Raman spectra of B and H differ very little from Raman spectra of the chromophores in vitro. The Raman scattering cross sections of B and H are 6-7 times larger than those for analogous modes of P at 278 K. The cross sections of B and of H are 3-4 times larger at 95 K than at 278 K, while the cross sections of P are approximately constant with temperature. The temperature dependence of the Raman cross sections for B and H suggests that pure dephasing arising from coupling to low-frequency solvent/protein modes is important in the damping of their excited states. The weak Raman cross sections of the special pair suggest that the excited state of P is damped by very rapid (<<30 fs) electronic relaxation processes. These resonance Raman spectra provide information for developing multimode vibronic models of the excited-state structure and dynamics of the chromophores in the RC.

UI MeSH Term Description Entries
D007259 Infrared Rays That portion of the electromagnetic spectrum usually sensed as heat. Infrared wavelengths are longer than those of visible light, extending into the microwave frequencies. They are used therapeutically as heat, and also to warm food in restaurants. Heat Waves,Heat Wave,Infrared Ray,Ray, Infrared,Rays, Infrared,Wave, Heat,Waves, Heat
D010674 Pheophytins Chlorophylls from which the magnesium has been removed by treatment with weak acid. Pheophytin
D004579 Electron Transport The process by which ELECTRONS are transported from a reduced substrate to molecular OXYGEN. (From Bennington, Saunders Dictionary and Encyclopedia of Laboratory Medicine and Technology, 1984, p270) Respiratory Chain,Chain, Respiratory,Chains, Respiratory,Respiratory Chains,Transport, Electron
D001429 Bacteriochlorophylls Pyrrole containing pigments found in photosynthetic bacteria. Bacteriochlorophyll
D012242 Rhodobacter sphaeroides Spherical phototrophic bacteria found in mud and stagnant water exposed to light. Rhodopseudomonas sphaeroides,Rhodobacter spheroides,Rhodopseudomonas spheroides
D013053 Spectrophotometry The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.
D013059 Spectrum Analysis, Raman Analysis of the intensity of Raman scattering of monochromatic light as a function of frequency of the scattered light. Raman Spectroscopy,Analysis, Raman Spectrum,Raman Optical Activity Spectroscopy,Raman Scattering,Raman Spectrum Analysis,Scattering, Raman,Spectroscopy, Raman
D013696 Temperature The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms. Temperatures
D045322 Photosynthetic Reaction Center Complex Proteins Protein complexes that take part in the process of PHOTOSYNTHESIS. They are located within the THYLAKOID MEMBRANES of plant CHLOROPLASTS and a variety of structures in more primitive organisms. There are two major complexes involved in the photosynthetic process called PHOTOSYSTEM I and PHOTOSYSTEM II. Photosynthetic Complex,Photosynthetic Reaction Center,Photosynthetic Reaction Center Complex Protein,Photosynthetic Complexes,Photosynthetic Reaction Centers,Center, Photosynthetic Reaction,Complex, Photosynthetic,Complexes, Photosynthetic,Reaction Center, Photosynthetic,Reaction Centers, Photosynthetic
D045342 Light-Harvesting Protein Complexes Complexes containing CHLOROPHYLL and other photosensitive molecules. They serve to capture energy in the form of PHOTONS and are generally found as components of the PHOTOSYSTEM I PROTEIN COMPLEX or the PHOTOSYSTEM II PROTEIN COMPLEX. Antenna Complexes, Light-Harvesting,Light-Harvesting Antenna Complexes,Light-Harvesting Chlorophyll Protein,Light-Harvesting Chlorophyll Protein Complexes,Antenna Complexes, Light Harvesting,Chlorophyll Protein, Light-Harvesting,Complexes, Light-Harvesting Antenna,Complexes, Light-Harvesting Protein,Light Harvesting Antenna Complexes,Light Harvesting Chlorophyll Protein,Light Harvesting Chlorophyll Protein Complexes,Light Harvesting Protein Complexes,Protein Complexes, Light-Harvesting

Related Publications

N J Cherepy, and A P Shreve, and L J Moore, and S G Boxer, and R A Mathies
January 1982, Annual review of biophysics and bioengineering,
N J Cherepy, and A P Shreve, and L J Moore, and S G Boxer, and R A Mathies
November 1988, Proceedings of the National Academy of Sciences of the United States of America,
N J Cherepy, and A P Shreve, and L J Moore, and S G Boxer, and R A Mathies
January 2000, Biopolymers,
N J Cherepy, and A P Shreve, and L J Moore, and S G Boxer, and R A Mathies
April 1987, FEBS letters,
N J Cherepy, and A P Shreve, and L J Moore, and S G Boxer, and R A Mathies
April 2011, Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy,
N J Cherepy, and A P Shreve, and L J Moore, and S G Boxer, and R A Mathies
January 2011, Doklady. Biochemistry and biophysics,
N J Cherepy, and A P Shreve, and L J Moore, and S G Boxer, and R A Mathies
April 1995, Biochemistry,
N J Cherepy, and A P Shreve, and L J Moore, and S G Boxer, and R A Mathies
October 1988, Proceedings of the National Academy of Sciences of the United States of America,
N J Cherepy, and A P Shreve, and L J Moore, and S G Boxer, and R A Mathies
November 1989, Biochimica et biophysica acta,
Copied contents to your clipboard!