Photochemical reaction center of new thermophilic photosynthetic bacteria.

Photochemical Hole-burning in Photosynthetic Reaction Centers

The change in absorbance (hole spectrum) of the primary electron donor (P870) in bacterial photosynthetic reaction centers has been studied at 1.5-2.1 K following narrow-band excitation at several wavelengths within the P870 absorption band. The hole width is very large, suggesting a homogeneous linewidth on the order of 200-300 cm-‘. Possible interpretations of this highly unusual result, incl...

Reaction centers of photosynthetic bacteria.

Cofactor-specific photochemical function resolved by ultrafast spectroscopy in photosynthetic reaction center crystals.

High-resolution mapping of cofactor-specific photochemistry in photosynthetic reaction centers (RCs) from Rhodobacter sphaeroides was achieved by polarization selective ultrafast spectroscopy in single crystals at cryogenic temperature. By exploiting the fixed orientation of cofactors within crystals, we isolated a single transition within the multicofactor manifold, and elucidated the site-spe...

Antennas and Reaction Centers of Photosynthetic Bacteria

Fluorescence and photochemical quenching in photosynthetic reaction centers.

Photosynthetic bacteria contain bacteriochlorophyll (BChl) that absorbs light and delivers the resulting singlet excitation energy to photochemical reaction centers.' The reaction centers, which have been isolated in a form free of lightharvesting BChl,'-3 contain a photochemically specialized BChl which in Rhodopseudomonas spheroides is called P870 after its absorption maximum near 870 nm. Exc...