title: Tissue-specific cadmium accumulation and its effects on nitrogen metabolism in tobacco (Nicotiana tabaccum, Bureley v. Fb9).
abstract: Tobacco (Nicotiana Tabaccum, Bureley v. Fb9) seedlings were grown for 30 days on control medium, and then treated for seven days with different concentrations (0, 10, 20, 50 and 100 muM) of CdCl(2). Cadmium (Cd) was mostly accumulated in the leaves. However, nitrate reductase and nitrite reductase activities (NR, EC 1.6.1.6 and NiR, EC 1.7.7.1) were more inhibited by Cd stress in the roots than in leaves. Glutamine synthetase activity (GS, EC 6.3.1.2) was inhibited by Cd treatment in roots and leaves. In both organs, aminating activity of glutamate dehydrogenase (GDH, EC 1.4.1.2) and protease activity were significantly stimulated in the leaves and roots of stressed plants. The lesser extents of Cd stress effects on leaves, despite their high Cd accumulation, suggest that: (i) tobacco leaves may evolve adaptive process to partially inactivate Cd ions; and (ii) tobacco is useful for phytoremediation.
authors.affiliation: Unité de recherche: Nutrition et métabolisme azotés et protéines de stress (99 UR /09-20), campus universitaire, faculté des sciences de Tunis, département de biologie, Université Tunis EL Manar, Tunis, Tunisia. houda_maaroufi@yahoo.fr
authors.forename: Houda
authors.initials: H
authors.lastname: Maaroufi Dguimi
authors.forename: Mohamed
authors.initials: M
authors.lastname: Debouba
authors.forename: Mohamed Habib
authors.initials: MH
authors.lastname: Ghorbel
authors.forename: Houda
authors.initials: H
authors.lastname: Gouia
mesh_terms: D001673:Biodegradation, Environmental; D019256:Cadmium Chloride / Q000032:analysis / Q000493:pharmacokinetics* / Q000494:pharmacology; D002734:Chlorophyll / Q000032:analysis; D004785:Environmental Pollutants / Q000493:pharmacokinetics; D005969:Glutamate Dehydrogenase / Q000378:metabolism; D050901:Nitrate Reductase / Q000037:antagonists & inhibitors; D009566:Nitrates / Q000032:analysis; D009572:Nitrite Reductases / Q000037:antagonists & inhibitors; D009584:Nitrogen / Q000378:metabolism; D009586:Nitrogen Fixation / Q000187:drug effects*; D009928:Organ Specificity; D010447:Peptide Hydrolases / Q000378:metabolism; D018515:Plant Leaves / Q000187:drug effects / Q000378:metabolism; D010940:Plant Proteins / Q000032:analysis / Q000037:antagonists & inhibitors / Q000187:drug effects; D018517:Plant Roots / Q000187:drug effects / Q000378:metabolism; D000644:Quaternary Ammonium Compounds / Q000032:analysis; D036226:Seedlings / Q000187:drug effects / Q000378:metabolism; D014026:Nicotiana / Q000033:anatomy & histology / Q000378:metabolism*
chemical_list: D004785:Environmental Pollutants; D009566:Nitrates; D010940:Plant Proteins; D000644:Quaternary Ammonium Compounds; D002734:Chlorophyll; D005969:Glutamate Dehydrogenase; D009572:Nitrite Reductases; D050901:Nitrate Reductase; D010447:Peptide Hydrolases; D019256:Cadmium Chloride; D009584:Nitrogen