Steglich C, Behrenfeld M, Koblizek M, Claustre H, Penno S, Prasil O, Partensky F, Hess W R
Humboldt University, Departmen of Biology, Berlin, Germany.
Biochim Biophys Acta. 2001 Jan 19;1503(3):341-9. doi: 10.1016/s0005-2728(00)00211-5.
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.
在海洋产氧光合细菌聚球藻（Prochlorococcus marinus）的分批培养中，研究了氮限制对光系统II（PSII）活性和藻红蛋白的影响。在氮限制条件下生长12小时内，观察到光化学量子产率（F(V)/F(M)）、热发光（TL）B带振幅和Q(A)再氧化速率显著下降。F(V)/F(M)的下降与TL B带振幅的变化平行，表明PSII活性丧失和无功能PSII中心的形成。这些变化伴随着D1蛋白含量的持续减少。相比之下，氮剥夺并未导致藻红蛋白含量显著降低。我们的结果反驳了藻红蛋白是聚球藻中氮储存复合物的观点。聚球藻中藻红蛋白基因表达的调控与迄今为止研究的典型含藻胆体蓝细菌和真核藻类不同。
