Peroxidase and hydrogen peroxide both play important roles in the final stages of the lignification pathway. Peroxidase, in the presence of H2O2 catalyses the oxidation of monolignols to give lignin. In order to examine this process we looked at lignification in transgenic tobacco plants expressing a barley peroxidase gene, HvPrx8, either alone or in combination with a wheat germin gene, g.f 2....

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...

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...

Even under optimal conditions, many metabolic processes, including the chloroplastic, mitochondrial, and plasma membrane-linked electron transport systems of higher plants, produce active oxygen species (AOS). Furthermore, the imposition of biotic and abiotic stress conditions can give rise to excess concentrations of AOS, resulting in oxidative damage at the cellular level. Therefore, antioxid...

Marigold plants (Calendula officinalis Linn) var. ‘Plamen Plus’ were grown under field conditions during the 2009 season in Trebišov, Slovakia and in Sofia, Bulgaria. The antioxidant potential in Slovak marigold flowers was due to the content of glutathione and ascorbate, two peroxidases (glutathione peroxidase and guaiacol peroxidase) and monodehydroascorbate reductase. The antioxidant capacit...

The effect of acidified calcium sulfate (ACS) on the quality of litchi ( Litchi chinensis Sonn. cv. 'Brewster') fruit after harvest was evaluated. ACS at 1.25% or higher concentrations significantly inhibited the activities of polyphenol oxidase and peroxidase in the pericarp during storage at both 5 and 10 degrees C. These treatments also effectively prevented browning and retained the red col...

The mitochondria of legume root nodules are critical to sustain the energy-intensive process of nitrogen fixation. They also generate reactive oxygen species at high rates and thus require the protection of antioxidant enzymes and metabolites. We show here that highly purified mitochondria from bean nodules (Phaseolus vulgaris L. cv. Contender x Rhizobium leguminosarum bv. phaseoli strain 3622)...

Bernhard Epping, Alexander P. Hansen and Peter Martin Institut für Pflanzenernährung (330), Fruwirthstr. 20, Universität Hohenheim, 70593 Stuttgart, Bundesrepublik Deutschland Z. Naturforsch. 50 c, 543-551 (1995); received March 15/May 2, 1995 Oxygen Derivates, Phaseolus vulgaris L.. Rhizobium leguminosarum, Rhizobium tropici, Symbiotic Effectivity Nodules of Rhizobium leguminosarum bv. phaseol...