A photoinduced persistent structural transformation of the special pair of a bacterial reaction center

Journal Article · Fri Apr 02 04:00:00 EST 1993 · Science (Washington, D.C.); (United States)

DOI:https://doi.org/10.1126/science.260.5104.68· OSTI ID:6434370

Reddy, N R.S.; Kolaczkowski, S V; Small, G J ^[1]

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1. Iowa State Univ., Ames (United States)

Structural modification of photosynthetic reaction centers is an important approach for understanding their charge-separation processes. An unprecedented persistent structural transformation of the special pair (dimer) of bacterioclorophyll molecules can be produced by light absorption alone. The nonphotochemical hole-burned spectra for the reaction center of Rhodopeseudomonas viridis show that the phototransformation leads to a red shift of 150 wave numbers for the special pair's lowest energy absorption band, P960, and a comparable blue shift for a state at 850 nanometers, which can now be definitively assigned as being most closely associated with the upper dimer component. Additional insights on excited-state electronic structure include the identification of a new state.

• OSTI ID: 6434370
• Journal Information: Science (Washington, D.C.); (United States), Journal Name: Science (Washington, D.C.); (United States) Vol. 260:5104; ISSN SCIEAS; ISSN 0036-8075
• Country of Publication: United States
• Language: English

Related Subjects

550200* -- Biochemistry
59 BASIC BIOLOGICAL SCIENCES
ABSORPTION
BACTERIA
CARBOXYLIC ACIDS
CHARGE DISTRIBUTION
CHLOROPHYLL
ELECTRIC CHARGES
ELECTRONIC STRUCTURE
ENERGY ABSORPTION
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
MICROORGANISMS
MOLECULES
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PHOTOSYNTHETIC BACTERIA
PHOTOSYNTHETIC REACTION CENTERS
PHYTOCHROMES
PIGMENTS
PORPHYRINS
PROTEINS
RED SHIFT
SEPARATION PROCESSES
SORPTION
SPECTRA