Journal of Experimental Botany, Vol. 51, No. 345, pp. 669-674,
April 2000
© 2000 Oxford University Press
The control of ascorbic acid synthesis and turnover in pea seedlings
School of Biological Sciences, University of Exeter, Hatherly Laboratories, Prince of Wales Road, Exeter EX4 4PS, UK
The rate of ascorbate synthesis and turnover in pea seedling embryonic axes was investigated in relation to its pool size. Ascorbate accumulated in embryonic axes of germinating pea seeds which has been supplied with ascorbate. Incorporation of [U-14C]glucose into ascorbate after a 2 h labelling period was reduced by ascorbate loading for 3 h and 20 h, providing evidence that ascorbate biosynthesis is inhibited by endogenous ascorbate. Ascorbate turnover was estimated by following the metabolism of [1-14C]ascorbate over 2 h after ascorbate loading and by the rate of decrease of the ascorbate pool size after ascorbate loading. Ascorbate turnover rate, determined by [1-14C]- ascorbate metabolism, increased as a linear function of pool size. The absolute turnover rate was higher in ascorbate-loaded embryonic axes but was always about 13% of the pool per hour. The initial rate of ascorbate turnover, estimated from the net decrease in pool size after ascorbate loading, also showed a similar turnover rate to that estimated from [1-14C]- ascorbate metabolism. Ascorbate loading had no effect on ascorbate peroxidase, monodehydroascorbate reductase, dehydroascorbate reductase or glutathione reductase activity. Ascorbate oxidase activity decreased after ascorbate loading.
Key words: Antioxidants, ascorbate, biosynthesis, metabolism, vitamin C.
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  A. Nunes-Nesi, R. Sulpice, Y. Gibon, and A. R. Fernie The enigmatic contribution of mitochondrial function in photosynthesis J. Exp. Bot., May 1, 2008; 59(7): 1675 - 1684. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Paradiso, R. Berardino, M. C. de Pinto, L. Sanita di Toppi, M. M. Storelli, F. Tommasi, and L. De Gara Increase in Ascorbate-Glutathione Metabolism as Local and Precocious Systemic Responses Induced by Cadmium in Durum Wheat Plants Plant Cell Physiol., March 1, 2008; 49(3): 362 - 374. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. Stevens, M. Buret, P. Duffe, C. Garchery, P. Baldet, C. Rothan, and M. Causse Candidate Genes and Quantitative Trait Loci Affecting Fruit Ascorbic Acid Content in Three Tomato Populations Plant Physiology, April 1, 2007; 143(4): 1943 - 1953. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. L. Conklin, S. Gatzek, G. L. Wheeler, J. Dowdle, M. J. Raymond, S. Rolinski, M. Isupov, J. A. Littlechild, and N. Smirnoff Arabidopsis thaliana VTC4 Encodes L-Galactose-1-P Phosphatase, a Plant Ascorbic Acid Biosynthetic Enzyme J. Biol. Chem., June 9, 2006; 281(23): 15662 - 15670. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. G Bartoli, J. Yu, F. Gomez, L. Fernandez, L. McIntosh, and C. H Foyer Inter-relationships between light and respiration in the control of ascorbic acid synthesis and accumulation in Arabidopsis thaliana leaves J. Exp. Bot., May 1, 2006; 57(8): 1621 - 1631. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Nishikawa, M. Kato, H. Hyodo, Y. Ikoma, M. Sugiura, and M. Yano Effect of sucrose on ascorbate level and expression of genes involved in the ascorbate biosynthesis and recycling pathway in harvested broccoli florets J. Exp. Bot., January 1, 2005; 56(409): 65 - 72. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. Kuzniak and M. Sklodowska The effect of Botrytis cinerea infection on the antioxidant profile of mitochondria from tomato leaves J. Exp. Bot., March 1, 2004; 55(397): 605 - 612. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Lorence, B. I. Chevone, P. Mendes, and C. L. Nessler myo-Inositol Oxygenase Offers a Possible Entry Point into Plant Ascorbate Biosynthesis Plant Physiology, March 1, 2004; 134(3): 1200 - 1205. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. A. Wolucka and M. Van Montagu GDP-Mannose 3',5'-Epimerase Forms GDP-L-gulose, a Putative Intermediate for the de Novo Biosynthesis of Vitamin C in Plants J. Biol. Chem., November 28, 2003; 278(48): 47483 - 47490. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. H. Millar, V. Mittova, G. Kiddle, J. L. Heazlewood, C. G. Bartoli, F. L. Theodoulou, and C. H. Foyer Control of Ascorbate Synthesis by Respiration and Its Implications for Stress Responses Plant Physiology, October 1, 2003; 133(2): 443 - 447. [Full Text] [PDF]
|
|
|
|
 |
|
 Z. Chen, T. E. Young, J. Ling, S.-C. Chang, and D. R. Gallie Increasing vitamin C content of plants through enhanced ascorbate recycling PNAS, March 18, 2003; 100(6): 3525 - 3530. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. R. Franceschi and N. M. Tarlyn L-Ascorbic Acid Is Accumulated in Source Leaf Phloem and Transported to Sink Tissues in Plants Plant Physiology, October 1, 2002; 130(2): 649 - 656. [Abstract] [Full Text] [PDF]
|
|