Theoretical Models of Electrochromic and Environmental Effects on Bacterio-Chlorophylls and -Pheophytins in Reaction Centers

  • Louise Karle Hanson
  • Mark A. Thompson
  • Michael C. Zerner
  • Jack Fajer
Chapter
Part of the NATO ASI Series book series (NSSA, volume 149)

Abstract

The primary charge separation in photosynthetic reaction centers (RC) is carried out by an array of (bacterio)chlorophylls arranged in close proximity. The recent x-ray structures of the RC complexes from Rhodopseudomonas viridis 1–3 and Rhodobacter sphaeroides 4,5 reveal two possible electron pathways for purple bacteria, only one of which is active.6 In order to determine the environmental factors most likely to affect the direction of electron flow in the nascent charge separation, we have calculated the effects of hydrogen bonding and chemical modification (enolization) by nearby residues upon the optical spectra, reduction potentials, unpaired spin density distributions and charge densities of bacterio-chlorophylls (BChl) and -pheophytins (BPh).

Keywords

Photosynthetic Bacterium Photosynthetic Reaction Center Primary Charge Separation Ring Versus Optical Shift 
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

  • Louise Karle Hanson
    • 1
  • Mark A. Thompson
    • 2
  • Michael C. Zerner
    • 2
  • Jack Fajer
    • 1
  1. 1.Department of Applied ScienceBrookhaven National LaboratoryUptonUSA
  2. 2.Quantum Theory ProjectUniversity of FloridaGainesvilleUSA

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