Hordeum vulgare and Hordeum maritimum respond to extended salinity stress displaying different temporal accumulation pattern of metabolites.

Hordeum maritimum With. (= H. marinum Huds.

Dataset on antioxidant metabolites and enzymes activities of freshly harvested sweet cherries ( L.) of Campania accessions.

In this article, we reported the original data obtained by the study of metabolites and enzymes involved in sweet cherry antioxidant system. We measured hydrogen peroxide (HO) and malondialdehyde (MDA), which are indicator of oxidative stress. Moreover, we measured the concentration of reduced and oxidized ascorbate and glutathione that are involved in ROS detoxification together with phenolics, anthocyanins and tocopherols.

Metabolic characterization and antioxidant activity in sweet cherry (Prunus avium L.) Campania accessions: Metabolic characterization of sweet cherry accessions.

The failure of the antioxidant scavenging system in advanced ripening stages, causing oxidative stress, is one of the most important factor of fruit decay. Production of rich antioxidant fruit could represent a way to delay fruit senescence and preserve its characteristics. We investigated the antioxidant metabolites (ascorbate, glutathione, tocopherols, and polyphenols) and enzymes (ascorbic peroxidases, peroxidases and polyphenol oxidases) involved in the antioxidant response in forty-three accessions of sweet cherry fruits from Campania region.

Durum Wheat Roots Adapt to Salinity Remodeling the Cellular Content of Nitrogen Metabolites and Sucrose.

Plants are currently experiencing increasing salinity problems due to irrigation with brackish water. Moreover, in fields, roots can grow in soils which show spatial variation in water content and salt concentration, also because of the type of irrigation. Salinity impairs crop growth and productivity by inhibiting many physiological and metabolic processes, in particular nitrate uptake, translocation, and assimilation.

Durum wheat seedling responses to simultaneous high light and salinity involve a fine reconfiguration of amino acids and carbohydrate metabolism.

Durum wheat plants are extremely sensitive to drought and salinity during seedling and early development stages. Their responses to stresses have been extensively studied to provide new metabolic targets and improving the tolerance to adverse environments. Most of these studies have been performed in growth chambers under low light [300-350 µmol m s photosynthetically active radiation (PAR), LL].

Trace metals, peroxidase activity, PAHs contents and ecophysiological changes in Quercus ilex leaves in the urban area of Caserta (Italy).

Trace metals and polycyclic aromatic hydrocarbons, severely affecting human, animal and plants health, highly contribute to the air pollution in urban areas mainly due to car traffic. In this study the air biomonitoring of the city of Caserta (South Italy) has been performed by using Quercus ilex L., a widespread ornamental plant in parks, gardens and avenues.

cDNA cloning and differential expression patterns of ascorbate peroxidase during post-harvest in Brassica rapa L.

Ascorbate is an antioxidant and a cofactor of many dioxygenases in plant and animal cell metabolism. A well-recognized enzyme consuming ascorbate is ascorbate peroxidase (APX), which catalyses the reduction of hydrogen peroxide to water with the simultaneous oxidation of ascorbate with a high specificity. The isolation and characterisation of new Apx cDNAs, could provide new insights about the physiological roles and regulation of these enzymes.

Salt-induced accumulation of glycine betaine is inhibited by high light in durum wheat.

In this study, we determined the effects of both salinity and high light on the metabolism of durum wheat (Triticum durum Desf. cv. Ofanto) seedlings, with a special emphasis on the potential role of glycine betaine in their protection.

Ttd1a promoter is involved in DNA-protein binding by salt and light stresses.

Stress modulation of retrotransposons may play a role in generating host genetic plasticity in response to environmental stress. Transposable elements have been suggested to contribute to the evolution of genes, by providing cis-regulatory elements leading to changes in expression patterns. Indeed, their promoter elements are similar to those of plant defence genes and may bind similar defence-induced transcription factors.

Polymorphism of a new Ty1-copia retrotransposon in durum wheat under salt and light stresses.

Long terminal repeat retrotransposons are the most abundant mobile elements in the plant genome and play an important role in the genome reorganization induced by environmental challenges. Their success depends on the ability of their promoters to respond to different signaling pathways that regulate plant adaptation to biotic and abiotic stresses. We have isolated a new Ty1-copia-like retrotransposon, named Ttd1a from the Triticum durum L.

Nitrogen metabolism in durum wheat under salinity: accumulation of proline and glycine betaine.

We studied the effect of salinity on amino acid, proline and glycine betaine accumulation in leaves of different stages of development in durum wheat under high and low nitrogen supply. Our results suggest that protective compounds against salt stress are accumulated in all leaves. The major metabolites are glycine betaine, which preferentially accumulates in younger tissues, and proline, which is found predominantly in older tissues.

Nitrate reductase in durum wheat seedlings as affected by nitrate nutrition and salinity.

The combined effects of nitrate (0, 0.1, 1, 10 mm) and salt (0, 100 mm NaCl) on nitrogen metabolism in durum wheat seedlings were investigated by analysis of nitrate reductase (NR) expression and activity, and metabolite content. High salinity (100 mm NaCl) reduced shoot growth more than root growth.

Free amino acids and glycine betaine in leaf osmoregulation of spinach responding to increasing salt stress.

•  The aim of the paper was to determine nitrogen compounds contributing to leaf cell osmoregulation of spinach (Spinacia oleracea) submitted to increasing salt stress. •  Sodium, free amino acids and glycine betaine contents were determined in the last fully expanded leaf of plants stressed by daily irrigation with saline water (0.17 M NaCl).

Coumarin inhibits the growth of carrot (Daucus carota L. cv. Saint Valery) cells in suspension culture.

We used a carrot (Daucus carota L. cv. Saint Valery) cell suspension culture as a simplified model system to study the effects of the allelochemical compound coumarin (1,2 benzopyrone) on cell growth and utilisation of exogenous nitrate, ammonium and carbohydrates.

Uptake and assimilation of nitrite in the acidophilic red alga Cyanidium caldarium Geitler.

The acidophilic red alga, Cyanidium caldarium Geitler, could use nitrite as a nitrogen source for growth, although this compound was very toxic in acidic media. Growth could be sustained when nitrite was added continuously at a rate lower than the maximum rate of nitrite assimilation for the culture. Nitrite assimilation was derepressed in cells growing on nitrate or nitrite, under nitrogen limitation and by nitrogen starvation.

Sea urchin DNA methyltransferases.

DNA methyltransferase activities have been partially purified from unfertilized eggs and blastula nuclei of sea urchin embryos. Comparative studies, using different DNAs as substrates, show that the two preparations are most active on hemimethylated and single-strand DNA, but they methylate, though at a lower rate, also on double-strand DNA. The two activities show distinctive efficiencies in methylating plasmid DNAs and marked differences in the rate of methyl transfer to DNAs in different structural states: linear, relaxed, or supercoiled.

Depression of nitrate reductase in the presence of excess ammonium in a unicellular alga growing under conditions of phosphate limitation.

Chemostat cultures of the unicellular alga Cyanidium caldarium have shown that under conditions of phosphate limitation nitrate reductase is completely derepressed even in cells growing in a large excess of ammonium, but that it occurs mainly in a catalytically inactive form. It is hypothesized that phosphate limitation contributes to maintaining intracellular level of glutamine suitable to stimulate inactivation but not repression of nitrate reductase. It is not excluded that in addition to variations in the intracellular level of glutamine, there are other metabolic events of the cell by which repression and inactivation of nitrate reductase could be differently influenced.

Active and inactive nitrate reductase. Effects of mild treatment with denaturing agents of protein.

Nitrate reductase (NAD(P)H:nitrate oxidoreductase, EC 1.6.6.

Studies on utilization of 2-ketoglutarate, glutamate and other amino acids by the unicellular alga Cyanidium caldarium.

Two strains of Cyandium caladarium which possess different biochemical and nutritional characteristics were examined with respect to their ability to utilize amino acids or 2-ketoglutarate as substrates. One strain utilizes alanine, glutamate or aspartate as nitrogen sources, and glutamate, alanine, or 2-ketoglutarate as carbon and energy sources for growth in the dark. The growth rate in the dark on 2-ketoglutarate is almost twice as high or higher than that on glutamate or alanine.