Abstract
The effect of light on the metabolism of ammonia was studied by subjecting detached maize leaves to 150 or 1350 μmol m−2 s−1 PAR during incubation with the leaf base in 2 mM 15NH4Cl. After up to 60 min, leaves were extracted. Ammonia, glutamine, glycine, serine, alanine, and aspartate were separated by isothermal distillation and ion exchange chromatography. 15N enrichments were analyzed by emission spectroscopy. The uptake of ammonium chloride did not influence CO2 assimilation (8.3 and 17.4 μmol m−1 s−1 at 150 and 1350 μmol m−2 s−1 PAR, respectively). Leaves kept at high light intensity contained more serine and less alanine than leaves from low light treatments. Within 1 h of incubation the enrichment of ammonia extracted from leaves rose to approximately 20% 15N. In the high light regime the amino acids contained up to 15% 15N, whereas in low light 15N enrichments were small (up to 6%). The kinetics of 15N incorporation indicated that NH3 was firstly assimilated into glutamine and then into glutamate. After 15 min 15N was also found in glycine, serine and alanine. At high light intensity nearly half of the 15N was incorporated in glycine. On the other hand, at low light intensity alanine was the predominant 15N sink. It is concluded that light influences ammonia assimilation at the glutamine synthetase reaction.
Similar content being viewed by others
References
Arnon DI (1949) Copper enzymes in isolated chloroplasts. Polyphenol oxidase in Beta vulgaris. Plant Physiol 24:1–15
Berger MG (1983) Uber den photorespiratiorischen Stickstoff-Stoffwechsel von Weizen- and Maisblattern. Ph D Thesis Kaiserslautern
Berger MG and Fock HP (1983) Effects of methionine sulfoximine on nitrogen metabolism of maize leaves in the light. Aust J Plant Physiol 10:187–194
Berger MG and Fock HP (1983) 15N and inhibitor studies on the photorespiratory nitrogen cycle in maize leaves. Photosynthesis Research 4: 3–7
Berger MG and Fock HP (1983) Turnover von Glycin, Glutamin und Glutamat Während der Photosynthese in Weizenblattern. Hopper-Seyler's Z Physiol Chem 364: 1097–1098
Canvin DT and Atkins CA (1974) Nitrate, nitrite and ammonia assimilation by leaves: effect of light, carbon dioxide and oxygen. Planta 116: 207–224
Givan CV (1975) Light-dependent synthesis of glutamine in pea-chloroplast preparations. Planta 122:281–291
Givan CV (1980) Aminotransferases in higher plants. In: Biochemistry of Plants 5 Amino acids and Derivatives (MJ Miflin ed.). Academic Press New York, 329–357
Hoagland DR and Arnon DI (1938) The water culture method for growing plants without soil. Univ Calif Coll Agric Circ 347: 1–39
Kanazawa T, Kanazawa K, Kirk MR and Bassham JA (1972) Regulatory effects of ammonia on carbon metabolism in Chlorella pyrenoidosa during photosynthesis and respiration. Biochim Biophys Acta 256: 656–669
Kedenburg CP (1971) A lithium buffer system for accelerated single-column amino acid analysis in physiological fluids. Analytical Biochem 40: 35–42
Keys AJ, Bird JF, Cornelius MJ, Lea PJ, Wallsgrove RM and Miflin BJ (1978) Photorespiratory nitrogen cycle. Nature 275: 741–743
Lawlor DW and Fock HP (1976) Photosynthetic assimilation of 14CO2 by waterstressed sunflower leaves at two O2 concentrations and the specific activity of products. J Exp Bot 28: 320–328
Lawyer AL, Cornwell KL, Larsen PO and Bassham JA (1981) Effects of carbon dioxide and oxygen on the regulation of photosynthetic carbon metabolism by ammonia in spinach mesophyll cells. Plant Physiol 68: 1231–1236
O'Neal TD and Joy KW (1975) Pea leaf glutamine synthetase. Regulatory properties. Plant Physiol 55: 968–974
Paul JS, Cornwell KL and Bassham JA (1978) Effects of ammonia on carbon metabolism in photosynthesizing isolated mesophyll cells from Papaver somniferum. Planta 142: 49–54
Platt SG, Plaut Z and Bassham JA (1977) Ammonia regulation of carbon metabolism in photosynthesizing leaf discs. Plant Physiol 60: 739–742
Santarius KA and Heber U (1965) Changes in the intracellular level of ATP, ADP, AMP and Pi and regulatory function of the adenylate system in leaf cells during photosynthesis. Biochim Biophys Acta 102: 39–54
Santarius KA and Stocking CR (1969) Intracellular localisation of enzymes in leaves and chloroplast membrane permeability to compounds involved in amino acid synthesis. Z Naturforchung 24b:1170–1179
Schnarrenberger C and Fock HP (1976) Interactions among organelles involved in photorespiration. In: Encycl Plant Physiol NS 3 pt III, Springer Berlin 185–234
Wong SC, Cowan JR and Farquhar GD (1978) Leaf Conductance in relation to assimilation in Eucalyptus paúciflora. Plant Physiol 62: 670–674
Woo KC, Berry JA and Turner GL (1978) Release and refixation of ammonia during photorespiration. Carnegie Inst Yearb 240–245
Woo KC and Canvin DT (1980) Effect of ammonia on photosynthetic carbon fixation in isolated spinach leaf cells. Can J Bot 58: 505–510
Woo KC and Osmond CB (1982) Stimulation of ammonia and 2-oxoglutarate-dependent O2 evolution in isolated chloroplasts by dicarboxylates and the role of the chloroplasts in photorespiratory nitrogen recycling. Plant Physiol 69: 591–596
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Klaus, R.E., Berger, M.G. & Fock, H.P. Effect of light intensity on ammonia assimilation in maize leaves. Photosynth Res 6, 221–228 (1985). https://doi.org/10.1007/BF00049278
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF00049278