The three-dimensional structure of the FMO protein from Pelodictyon phaeum and the implications for energy transfer

Chadwick R. Larson, Chenda O. Seng, Lisa Lauman, Heather J. Matthies, Jianzhong Wen, Robert E. Blankenship, James Allen

Research output: Contribution to journalArticlepeer-review

28 Scopus citations


The Fenna-Matthews-Olson (FMO) antenna protein from the green bacterium Pelodictyon phaeum mediates the transfer of energy from the peripheral chlorosome antenna complex to the membrane-bound reaction center. The three-dimensional structure of this protein has been solved using protein crystallography to a resolution limit of 2.0 Å, with Rwork and Rfree values of 16.6 and 19.9%, respectively. The structure is a trimer of three identical subunits related by a threefold symmetry axis. Each subunit has two beta sheets that surround 8 bacteriochlorophylls. The bacteriochlorophylls are all five-coordinated, with the axial ligand being a histidine, serine, backbone carbonyl, or bound water molecule. The arrangement of the bacteriochlorophylls is generally well conserved in comparison to other FMO structures, but differences are apparent in the interactions with the surrounding protein. In this structure the position and orientation of the eighth bacteriochlorophyll is well defined and shows differences in its location and the coordination of the central Mg compared to previous models. The implications of this structure on the ability of the FMO protein to perform energy transfer are discussed in terms of the experimental optical measurements.

Original languageEnglish (US)
Pages (from-to)139-150
Number of pages12
JournalPhotosynthesis research
Issue number2
StatePublished - Feb 2011


  • Chlorosome
  • Energy transfer
  • Green bacteria
  • Light-harvesting complex
  • Photosynthesis

ASJC Scopus subject areas

  • Biochemistry
  • Plant Science
  • Cell Biology


Dive into the research topics of 'The three-dimensional structure of the FMO protein from Pelodictyon phaeum and the implications for energy transfer'. Together they form a unique fingerprint.

Cite this