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Bacterial Reaction Centers are Intrinsically Heterogeneous

  • A. J. Hoff
Chapter
Part of the NATO ASI Series book series (NSSA, volume 149)

Abstract

The reaction center is, by definition, the (aggregate of) protein molecule(s) which houses the components involved in the primary charge separation and charge stabilizing reactions. It can be isolated, purified, crystallized and X-rayed. Its atomic structure is known with a resolution of 2.3 Å (Deisenhofer et al, 1985, and Deisenhofer, J., private communication), the atomic coordinates to within 0.2 Å. Spectral simulations based on the X-ray structure are highly successful (Knapp et al., 1986; Vasmel et al, 1986; Lous and Hoff, 1987a). The conclusion seems warranted that, at least for any particular bacterial species, a unique reaction center structure indeed exists. This notion has led to efforts to calculate from the crystal structure in great detail electronic spin and charge densities, overlap integrals, electron transfer matrix elements etc. (Plato et al., 1986; Warshel and Parson, 1987; Parson and Warshel, 1987). In this note I will show that such ventures may be overly optimistic. A number of experiments bear out that considerable heterogeneity in detailed reaction center structure exists that affects markedly the spectral properties of the reaction center. It is not unlikely that this heterogeneity also affects electron transport properties.

Keywords

Triplet State Photosynthetic Bacterium Primary Donor Charge Transfer State Photosynthetic Reaction Center 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1988

Authors and Affiliations

  • A. J. Hoff
    • 1
  1. 1.Department of Biophysics, Huygens LaboratoryState University of LeidenThe Netherlands

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