Abstract
Nitrate utilization has been characterized in nitrogen-deficient cells of the marine diatom Skeletonema costatum. In order to separate nitrate uptake from nitrate reduction, nitrate reductase activity was suppressed with tungstate. Neither nitrite nor the presence of amino acids in the external medium or darkness affects nitrate uptake kinetics. Ammonium strongly inhibits carrier-mediated nitrate uptake, without affecting diffusion transfer. A model is proposed for the uptake and assimilation of nitrate in S. costatum and their regulation by ammonium ions.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Filner P., Varner J. E., Wray J. L. Environmental or developmental changes cause many enzyme activities of higher plants to rise or fall. Science. 1969 Jul 25;165(3891):358–367. doi: 10.1126/science.165.3891.358. [DOI] [PubMed] [Google Scholar]
- Goldsmith J., Livoni J. P., Norberg C. L., Segel I. H. Regulation of Nitrate Uptake in Penicillium chrysogenum by Ammonium Ion. Plant Physiol. 1973 Oct;52(4):362–367. doi: 10.1104/pp.52.4.362. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Heimer Y. M., Filner P. Regulation of the nitrate assimilation pathway in cultured tobacco cells. 3. The nitrate uptake system. Biochim Biophys Acta. 1971 Feb 23;230(2):362–372. doi: 10.1016/0304-4165(71)90223-6. [DOI] [PubMed] [Google Scholar]
- Heimer Y. M., Wray J. L., Filner P. The effect of tungstate on nitrate assimilation in higher plant tissues. Plant Physiol. 1969 Aug;44(8):1197–1199. doi: 10.1104/pp.44.8.1197. [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]
- Schloemen R. H., Garrett R. H. Nitrate transport system in Neurospora crassa. J Bacteriol. 1974 Apr;118(1):259–269. doi: 10.1128/jb.118.1.259-269.1974. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Serra J. L., Llama M. J., Cadenas E. Nitrate Utilization by the Diatom Skeletonema costatum: I. Kinetics of Nitrate Uptake. Plant Physiol. 1978 Dec;62(6):987–990. doi: 10.1104/pp.62.6.987. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Vila R., Bárcena J. A., Llobell A., Paneque A. Characterization of a membrane-bound nitrate reductase from Azotobacter chroococcum. Biochem Biophys Res Commun. 1977 Apr 11;75(3):682–688. doi: 10.1016/0006-291x(77)91526-1. [DOI] [PubMed] [Google Scholar]