Dissection of respiration and photosynthesis in the cyanobacterium Synechocystis sp. PCC6803 by the analysis of chlorophyll fluorescence

Takako Ogawa, Kintake Sonoike

Research output: Contribution to journalArticle

5 Citations (Scopus)


In cyanobacteria, photosynthesis and respiration share some components of electron transport chain. To explore the interaction between photosynthesis and respiration, we monitored the change in the yield of chlorophyll fluorescence due to state transition in ndh genes disruptants, deficient in NAD(P)H dehydrogenase (NDH-1) complexes serving for respiration or for carbon concentrating mechanism (CCM). The disruption of ndh genes essential for respiration resulted in low levels of chlorophyll fluorescence quenching in the dark (NPQDark) as well as in the low light (NPQLL). The lowered NPQDark and NPQLL in these ndh genes disruptants could be ascribed to the oxidation of the PQ pool due to the poor electron supply from NDH-1 complexes in respiratory electron transport. On the other hand, only NPQLL decreased upon disruption of the ndh genes essential for CCM. We propose that, in the disruptants of these ndh genes, the PQ pool is oxidized in the light through the increased photosystem I content, resulting in the lowered NPQLL. Apparently, the two different subsets of ndh genes affect photosynthetic electron transport although in totally different manners. It is also suggested that monitoring state transition is a simple method to evaluate the condition of photosynthesis, respiration and CCM.

Original languageEnglish
Pages (from-to)61-67
Number of pages7
JournalJournal of Photochemistry and Photobiology B: Biology
Publication statusPublished - 2015 Mar


ASJC Scopus subject areas

  • Radiation
  • Radiological and Ultrasound Technology
  • Biophysics
  • Radiology Nuclear Medicine and imaging

Cite this