Abstract
The effect of nitrogen and sulfur nutrition on sulfate permease and O-acetylserine sulfhydrylase was studied in tobacco cells.
Sulfate transport rates increased 10-fold in cells transferred to sulfur-deficient B-5 medium. The addition of either sulfate or l-cysteine reduced transport 95 and 80%, respectively. The pools of sulfate, cysteine, glutathione, and methionine declined in sulfur-starved cells. The addition of either sulfate or l-cysteine increased the pools of sulfur-containing compounds, but major quantitative differences were measured. Nitrogen-starved cells had low transport rates which were not increased by addition of nitrate/ammonia. The pools of sulfate, cysteine, and methionine were high in nitrogen-starved cells and remained high upon addition of a nitrogen source. The results show that sulfate transport is regulated by the intracellular sulfate pool.
O-Acetylserine sulfhydrylase was not affected by sulfur nutrition. The extractable activity was high in B-5-grown cells, sulfur-deficient cells, and cells to which either sulfate or l-cysteine had been added. In contrast, the enzyme declined in cells transferred to nitrogen-deficient medium and the amount of enzyme/g fresh weight increased 10-fold when nitrate/ammonia was added. The addition of nitrate/ammonia had no effect on the cysteine or methionine pools but increased the total amino acid pool. The amount of O-acetylserine was positively correlated with extractable enzyme activity. This enzyme is positively regulated by an effector (possibly O-acetylserine) which is high under conditions of net nitrate assimilation.
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- Bertagnolli B. L., Wedding R. T. Purification and initial kinetic characterization of different forms of o-acetylserine sulfhydrylase from seedlings of two species of phaseolus. Plant Physiol. 1977 Jul;60(1):115–121. doi: 10.1104/pp.60.1.115. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Borum P. R., Monty K. J. Regulatory mutants and control of cysteine biosynthetic enzymes in Salmonella typhimurium. J Bacteriol. 1976 Jan;125(1):94–101. doi: 10.1128/jb.125.1.94-101.1976. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Brunold C. Regulation of Sulfate Assimilation in Plants: 7. Cysteine Inactivation of Adenosine 5'-Phosphosulfate Sulfotransferase in Lemna minor L. Plant Physiol. 1978 Mar;61(3):342–347. doi: 10.1104/pp.61.3.342. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chambers L. A., Trudinger P. A. Cysteine and S-sulphocysteine biosynthesis in bacteria. Arch Mikrobiol. 1971;77(2):165–184. doi: 10.1007/BF00408609. [DOI] [PubMed] [Google Scholar]
- Datko A. H., Mudd S. H., Giovanelli J., Macnicol P. K. Sulfur-containing Compounds in Lemna perpusilla 6746 Grown at a Range of Sulfate Concentrations. Plant Physiol. 1978 Oct;62(4):629–635. doi: 10.1104/pp.62.4.629. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gamborg O. L. The effects of amino acids and ammonium on the growth of plant cells in suspension culture. Plant Physiol. 1970 Apr;45(4):372–375. doi: 10.1104/pp.45.4.372. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Harrington H. M., Smith I. K. Cysteine metabolism in cultured tobacco cells. Plant Physiol. 1980 Jan;65(1):151–155. doi: 10.1104/pp.65.1.151. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kredich N. M. Regulation of L-cysteine biosynthesis in Salmonella typhimurium. I. Effects of growth of varying sulfur sources and O-acetyl-L-serine on gene expression. J Biol Chem. 1971 Jun 10;246(11):3474–3484. [PubMed] [Google Scholar]
- LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
- Owens T., Poole R. J. Regulation of cytoplasmic and vacuolar volumes by plant cells in suspension culture. Plant Physiol. 1979 Nov;64(5):900–904. doi: 10.1104/pp.64.5.900. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Reuveny Z. Derepression of ATP sulfurylase by the sulfate analogs molybdate and selenate in cultured tobacco cells. Proc Natl Acad Sci U S A. 1977 Feb;74(2):619–622. doi: 10.1073/pnas.74.2.619. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Smith I. K. Sulfate transport in cultured tobacco cells. Plant Physiol. 1975 Feb;55(2):303–307. doi: 10.1104/pp.55.2.303. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Umbarger H. E. Amino acid biosynthesis and its regulation. Annu Rev Biochem. 1978;47:532–606. doi: 10.1146/annurev.bi.47.070178.002533. [DOI] [PubMed] [Google Scholar]