Energy transfer processes in chlorophyll f-containing cyanobacteria using time-resolved fluorescence spectroscopy on intact cells

Biochim Biophys Acta. 2014 Sep;1837(9):1484-9. doi: 10.1016/j.bbabio.2014.04.009. Epub 2014 Apr 30.


We examined energy transfer dynamics in the unique chlorophyll (Chl) f-containing cyanobacterium Halomicronema hongdechloris. The absorption band of Chl f appeared during cultivation of this organism under far-red light. The absorption maximum of Chl f in organic solvents occurs at a wavelength of approximately 40 nm longer than that of Chl a. In vivo, the cells display a new absorption band at approximately 730 nm at 298 K, which is at a significantly longer wavelength than that of Chl a. We primarily assigned this band to a long wavelength form of Chl a. The function of Chl f is currently unknown. We measured the fluorescence of cells using time-resolved fluorescence spectroscopy in the picosecond-to-nanosecond time range and found clear differences in fluorescence properties between the cells that contained Chl f and the cells that did not. After excitation, the fluorescence peaks of photosystem I and photosystem II appeared quickly but diminished immediately. A unique fluorescence peak located at 748 nm subsequently appeared in cells containing Chl f. This finding strongly suggests that the Chl f in this alga exists in photosystem I and II complexes and is located close to each molecule of Chl a. This article is part of a special issue entitled: photosynthesis research for sustainability: keys to produce clean energy.

Keywords: Chlorophyll f; Energy transfer; Fluorescence; Photosynthesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chlorophyll / analogs & derivatives*
  • Chlorophyll / chemistry
  • Cyanobacteria / metabolism*
  • Energy Transfer
  • Spectrometry, Fluorescence / methods*


  • chlorophyll f
  • Chlorophyll