Infection of tomato leaves with the necrotrophic fungus Botrytis cinerea resulted in substantial changes in enzymatic and non-enzymatic components of the ascorbate-glutathione cycle as well as in superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), glutathione transferase (GST), and l-galactono-gamma-lactone dehydrogenase (GLDH) activities. In the initial phase of the 5 d experiment CuZ...

A NAD(P)H oxidizing system (NAAP) was detected and partially purified from leaves of spinach and Sedum praealtum, seeds and leaves of pea and cells of green and red algae which oxidized NAD(P)H in the presence of ascorbate and H(2)O(2).The partially-purified spinach system had substrate K(m) values of 5 micromolar for NADH, 50 micromolar for H(2)O(2), and 300 micromolar for l-ascorbic acid at t...

Switchgrass (Panicum virgatum L.) is being developed as a bioenergy species. Recently an early version of its genome has been released permitting a route to the cloning and analysis of key proteins. Ascorbate peroxidases (APx) are an important part of the antioxidant defense system of plant cells and present a well studied model to understand structure-function relationships. Analysis of the ge...

The purpose of the current study was to determine possible improvement in soybean plants’ tolerance against vanadium-induced stress response application olive solid waste (OSW) and selenium nanoparticles (Se-NPs), by assessing metabolites plant defense systems. Drawing upon this aim, a pot experiment performed where plants were grown with fertilization treatment (including, control, OSW, Se-NPs...

Ascorbate peroxidase (APX) is a crucial, haeme-containing enzyme of the ascorbate glutathione cycle that detoxifies reactive oxygen species in plants by catalyzing the conversion of hydrogen peroxide to water using ascorbate as a specific electron donor. Different APX isoforms are present in discrete subcellular compartments in rice and their expression is stress regulated. We revealed the homo...

The glutathione peroxidase-glutathione reductase system, an alternative pathway for metabolic utilization of H2O2 [Chance, Sies & Boveris (1979) Physiol. Rev. 59, 527-605], was investigated in Trypanosoma cruzi, an organism lacking catalase and deficient in peroxidase [Boveris & Stoppani (1977) Experientia 33, 1306-1308]. The presence of glutathione (4.9 +/- 0.7 nmol of reduced glutathione/10(8...

The effects of double stress environment i.e. lead (heavy metal) and NaCl (saline) on the activity of antioxidant enzymes in Vigna radiata seedling were studied. The antioxidant activities of enzymes, i.e of superoxide dismutase, catalase, ascorbate peroxidase, guaiacol peroxidase, glutathione reductase and their activity proportions were examined. Superoxide dismutase, ascorbate peroxidase, gu...

Large changes occur in the ascorbate system during the development of Vicia faba seed and these appear closely related to what are generally considered to be the three stages of embryogenesis. During the first stage, characterized by embryonic cells with high mitotic activity, the ascorbic acid/dehydroascorbic acid ratio is about 7, whereas in the following stage, characterized by rapid cell el...

We conducted a comparative analysis of biochemical parameters for the ascorbate-glutathione cycle in non-transgenic and transgenic Nicotiana tabacum, plants cultivated heavy metal polluted soils. Transgenic had their genome bacterial acdS-gene encoding 1-aminocyclopropane-1-carboxylate deaminase (ACC-deaminase) enzyme. The introduction elevated concentrations copper, chromium, lead ions into so...