Abstract
Action spectra for the assimilation of nitrate and nitrite have been obtained for several blue-green algae (cyanobacteria) with different accessory pigment composition. The action spectra for both nitrate and nitrite utilization by nitrate-grown Anacystis nidulans L-1402-1 cells exhibited a clear peak at about 620 nanometers, corresponding to photosystem II (PSII) C-phycocyanin absorption, the contribution of chlorophyll a (Chl a) being barely detectable. The action spectrum for nitrate reduction by a nitrite reductase mutant of A. nidulans R2 was very similar. All these action spectra resemble the fluorescence excitation spectrum of cell suspensions of the microalgae monitored at 685 nanometers—the fluorescence band of Chl a in PSII. In contrast, the action spectrum for nitrite utilization by nitrogen-starved A. nidulans cells, which are depleted of C-phycocyanin, showed a maximum near 680 nanometers, attributable to Chl a absorption. The action spectrum for nitrite utilization by Calothrix sp. PCC 7601 cells, which contain both C-phycoerythrin and C-phycocyanin as PSII accessory pigments, presented a plateau in the region from 550 to 630 nanometers. In this case, there was also a clear parallelism between the action spectrum and the fluorescence excitation spectrum, which showed two overlapped peaks with maxima at 562 and 633 nanometers. The correlation observed between the action spectra for both nitrate and nitrite assimilation and the light-harvesting pigment content of the blue-green algae studied strongly suggests that phycobiliproteins perform a direct and active role in these photosynthetic processes.
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Selected References
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- Allen M. M., Smith A. J. Nitrogen chlorosis in blue-green algae. Arch Mikrobiol. 1969;69(2):114–120. doi: 10.1007/BF00409755. [DOI] [PubMed] [Google Scholar]
- Cobley J. G., Miranda R. D. Mutations affecting chromatic adaptation in the cyanobacterium Fremyella diplosiphon. J Bacteriol. 1983 Mar;153(3):1486–1492. doi: 10.1128/jb.153.3.1486-1492.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Herrero A., Flores E., Guerrero M. G. Regulation of nitrate reductase levels in the cyanobacteria Anacystis nidulans, Anabaena sp. strain 7119, and Nostoc sp. strain 6719. J Bacteriol. 1981 Jan;145(1):175–180. doi: 10.1128/jb.145.1.175-180.1981. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kuhlemeier C. J., Logtenberg T., Stoorvogel W., van Heugten H. A., Borrias W. E., van Arkel G. A. Cloning of nitrate reductase genes from the cyanobacterium Anacystis nidulans. J Bacteriol. 1984 Jul;159(1):36–41. doi: 10.1128/jb.159.1.36-41.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lara C., Romero J. M. Distinctive Light and CO(2)-Fixation Requirements of Nitrate and Ammonium Utilization by the Cyanobacterium Anacystis nidulans. Plant Physiol. 1986 Jun;81(2):686–688. doi: 10.1104/pp.81.2.686. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lemasson C., Marsac N. T., Cohen-Bazire G. Role of allophycocyanin as light-harvesting pigment in cyanobacteria. Proc Natl Acad Sci U S A. 1973 Nov;70(11):3130–3133. doi: 10.1073/pnas.70.11.3130. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Manzano C., Candau P., Gomez-Moreno C., Relimpio A. M., Losada M. Ferredoxin-dependent photosynthetic reduction of nitrate and nitrite by particles of Anacystis nidulans. Mol Cell Biochem. 1976 Feb 25;10(3):161–169. doi: 10.1007/BF01731687. [DOI] [PubMed] [Google Scholar]
- Manzano C., Candau P., Guerrero M. G. Affinity chromatography of Anacystis nidulans ferredoxin nitrate reductase and NADP reductase on reduced ferredoxin-Sepharose. Anal Biochem. 1978 Oct 1;90(1):408–412. doi: 10.1016/0003-2697(78)90044-1. [DOI] [PubMed] [Google Scholar]
- Stevens S. E., Van Baalen C. Characteristics of Nitrate Reduction in a Mutant of the Blue-Green Alga Agmenellum quadruplicatum. Plant Physiol. 1973 Feb;51(2):350–356. doi: 10.1104/pp.51.2.350. [DOI] [PMC free article] [PubMed] [Google Scholar]