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Updated: Oct 10, 2026

Isolation and Characterization of Intact Phycobilisome in Cyanobacteria
Published on: November 10, 2021
Nitrogen deprivation strongly affects photosystem II but not phycoerythrin level in the divinyl-chlorophyll
C Steglich1, M Behrenfeld, M Koblizek
1Humboldt University, Departmen of Biology, Berlin, Germany.
Abstract:
Effects of nitrogen limitation on Photosystem II (PSII) activities and on phycoerythrin were studied in batch cultures of the marine oxyphotobacterium Prochlorococcus marinus. Dramatic decreases in photochemical quantum yields (F(V)/F(M)), the amplitude of thermoluminescence (TL) B-band, and the rate of Q(A) reoxidation were observed within 12 h of growth in nitrogen-limited conditions. The decline in F(V)/F(M) paralleled changes in the TL B-band amplitude, indicative of losses in PSII activities and formation of non-functional PSII centers. These changes were accompanied by a continuous reduction in D1 protein content. In contrast, nitrogen deprivation did not cause any significant reduction in phycoerythrin content. Our results refute phycoerythrin as a nitrogen storage complex in Prochlorococcus. Regulation of phycoerythrin gene expression in Prochlorococcus is different from that in typical phycobilisome-containing cyanobacteria and eukaryotic algae investigated so far.
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