skip to main content


Title: Population-level coordination of pigment response in individual cyanobacterial cells under altered nitrogen levels

Cyanobacterial phycobilisome (PBS) pigment-protein complexes harvest light and transfer the energy to reaction centers. Previous ensemble studies have shown that cyanobacteria respond to changes in nutrient availability by modifying the structure of PBS complexes, but this process has not been visualized for individual pigments at the single-cell level due to spectral overlap. We characterized the response of four key photosynthetic pigments to nitrogen depletion and repletion at the subcellular level in individual, live Synechocystis sp. PCC 6803 cells using hyperspectral confocal fluorescence microscopy and multivariate image analysis. Our results revealed that PBS degradation and re-synthesis comprise a rapid response to nitrogen fluctuations, with coordinated populations of cells undergoing pigment modifications. Chlorophyll fluorescence originating from photosystem I and II decreased during nitrogen starvation, but no alteration in subcellular chlorophyll localization was found. Lastly, we observed differential rod and core pigment responses to nitrogen deprivation, suggesting that PBS complexes undergo a stepwise degradation process.
 [1] ; ORCiD logo [2] ; ORCiD logo [3] ;  [4] ; ORCiD logo [5] ; ORCiD logo [4] ; ORCiD logo [1]
  1. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
  2. Washington Univ., St. Louis, MO (United States); Univ. of Colorado, Boulder, CO (United States)
  3. Washington Univ., St. Louis, MO (United States); United States Environmental Protection Agency, Washington, D.C. (United States)
  4. Washington Univ., St. Louis, MO (United States)
  5. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Old Dominion Univ., Norfolk, VA (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 0166-8595; PII: 422
Grant/Contract Number:
AC04-94AL85000; SC0001035; NA0003525
Published Article
Journal Name:
Photosynthesis Research
Additional Journal Information:
Journal Volume: 134; Journal Issue: 2; Journal ID: ISSN 0166-8595
Research Org:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
59 BASIC BIOLOGICAL SCIENCES; 60 APPLIED LIFE SCIENCES; Cyanobacteria; Photosynthesis; Phycobilisome; Nitrogen; Hyperspectral confocal fluorescence microscopy; Multivariate analysis
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1374747