Abstract
The effect of the nitrogen source on the cellular activity of ferredoxin-nitrate reductase in different cyanobacteria was examined. In the unicellular species Anacystis nidulans, nitrate reductase was repressed in the presence of ammonium but de novo enzyme synthesis took place in media containing either nitrate or not nitrogen source, indicating that nitrate was not required as an obligate inducer. Nitrate reductase in A. nidulans was freed from ammonium repression by L-methionine-D,L-sulfoximine, an irreversible inhibitor of glutamine synthetase. Ammonium-promoted repression appears therefore to be indirect; ammonium has to be metabolized through glutamine synthetase to be effective in the repression of nitrate reductase. Unlike the situation in A. nidulans, nitrate appeared to play an active role in nitrate reductase synthesis in the filamentous nitrogen-fixing strains Anabaena sp. strain 7119 and Nostoc sp. strain 6719, with ammonium acting as an antagonist with regard to nitrate.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Dunn-Coleman N. S., Tomsett A. B., Garrett R. H. Nitrogen metabolite repression of nitrate reductase in Neurospora crassa: effect of the gln-1a locus. J Bacteriol. 1979 Aug;139(2):697–700. doi: 10.1128/jb.139.2.697-700.1979. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Garrett R. H., Amy N. K. Nitrate assimilation in fungi. Adv Microb Physiol. 1978;18:1–65. doi: 10.1016/s0065-2911(08)60414-2. [DOI] [PubMed] [Google Scholar]
- Guerrero M. G., Vega J. M., Leadbetter E., Losada M. Preparation and characterization of a soluble nitrate reductase from Azotobacter chroococcum. Arch Mikrobiol. 1973 Jun 25;91(4):287–304. doi: 10.1007/BF00425049. [DOI] [PubMed] [Google Scholar]
- Herrera J., Paneque A., Maldonado J. M., Barea J. L., Losada M. Regulation by ammonia of nitrate reductase synthesis and activity in Chlamydomonas reinhardi. Biochem Biophys Res Commun. 1972 Aug 21;48(4):996–1003. doi: 10.1016/0006-291x(72)90707-3. [DOI] [PubMed] [Google Scholar]
- Meeks J. C., Wolk C. P., Lockau W., Schilling N., Shaffer P. W., Chien W. S. Pathways of assimilation of [13N]N2 and 13NH4+ by cyanobacteria with and without heterocysts. J Bacteriol. 1978 Apr;134(1):125–130. doi: 10.1128/jb.134.1.125-130.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Premakumar R., Sorger G. J., Gooden D. Nitrogen metabolite repression of nitrate reductase in Neurospora crassa. J Bacteriol. 1979 Mar;137(3):1119–1126. doi: 10.1128/jb.137.3.1119-1126.1979. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rigano C., Violante U. Effect of nitrate, ammonia and nitrogen starvation on the regulation of nitrate reductase in Cyanidium caldarium. Arch Mikrobiol. 1973 Mar 2;90(1):27–33. doi: 10.1007/BF00424821. [DOI] [PubMed] [Google Scholar]
- Sorger G. J., Davies J. Regulation of nitrate reductase of Neurospora at the level of transcription and translation. Biochem J. 1973 Jul;134(3):673–685. doi: 10.1042/bj1340673. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stewart W. D., Rowell P. Effects of L-methionine-DL-sulphoximine on the assimilation of newly fixed NH3, acetylene reduction and heterocyst production in Anabaena cylindrica. Biochem Biophys Res Commun. 1975 Aug 4;65(3):846–856. doi: 10.1016/s0006-291x(75)80463-3. [DOI] [PubMed] [Google Scholar]
- Vega J. M., Herrera J., Aparicio P. J., Paneque A., Losada M. Role of molybdenum in nitrate reduction by chlorella. Plant Physiol. 1971 Sep;48(3):294–299. doi: 10.1104/pp.48.3.294. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Villalobo A., Roldán J. M., Rivas J., CárdenasJ Assimilatory nitrate reductase from Acinetobacter calcoaceticus. Arch Microbiol. 1977 Mar 1;112(2):127–132. doi: 10.1007/BF00429324. [DOI] [PubMed] [Google Scholar]