2RCR: Photosynthetic Reaction Center

The structure to the right is a membrane-bound photosynthetic reaction center from the species Rhodobacter sphaeroides. Identify the following:

  • The three hydrophobic subunits: H, L, and M
  • Four bacteriochlorophyll (BChl) molecules
  • Two bacteriopheophytin (BPheo) molecules (*What is the basic difference between BPheo and BChl?)
  • Two ubiquinone (QB) or one ubiquinone and one menaquinone (QA) molecules
  • Fe (II) atom
  • Mg(II) atoms
  • Describe the general symmetry in the arrangement of these prosthetic groups
  • Locate the "special pair"