Effect of different metals on protease activity in sunflower cotyledons

Proteases are crucial for living cells and play a role in plant cell adaptation to environmental conditions. Oxidative stress produced oxidized proteins which are selectively degraded by proteases. To understand the role of proteolysis in response to metal stress, sunflower plants (a plant suitable for phytoremediation) were treated with 100 \u3bcM of CdCl2, CuCl2, AlCl3, CoCl2, PbCl2, CrCl3, NiCl2, HgCl2 or ZnCl2. Changes in protease activity, gelatinase profile and protein oxidation were examined in sunflower cotyledons. Our results indicate that this tissue has mainly acid proteases belonging to different classes. Although all metals (except Zn) increased protein oxidation (62, 57, 112, 74, 74, 68, 64 and 40% for Pb, Al, Ni, Cd, Hg, Co, Cr and Cu over the control), they altered proteolysis in different ways. Pb, Al and Ni treatment decreased protease activity 22, 28 and 30% respect to control while Cd and Hg increased this activity in 23 and 27%. In Zn, Cu and Co treatments protease activity remained similar to control treatment. These results indicate that different proteases are involved in plant defence against metal toxicity. However, the identification of specific oxidized proteins involved in this process and the metal effect on class specific proteases should provide greater information

Effect of different metals on protease activity in sunflower cotyledons

Proteases are crucial for living cells and play a role in plant cell adaptation to environmental conditions. Oxidative stress produced oxidized proteins which are selectively degraded by proteases. To understand the role of proteolysis in response to metal stress, sunflower plants (a plant suitable for phytoremediation) were treated with 100 \u3bcM of CdCl2, CuCl2, AlCl3, CoCl2, PbCl2, CrCl3, NiCl2, HgCl2 or ZnCl2. Changes in protease activity, gelatinase profile and protein oxidation were examined in sunflower cotyledons. Our results indicate that this tissue has mainly acid proteases belonging to different classes. Although all metals (except Zn) increased protein oxidation (62, 57, 112, 74, 74, 68, 64 and 40% for Pb, Al, Ni, Cd, Hg, Co, Cr and Cu over the control), they altered proteolysis in different ways. Pb, Al and Ni treatment decreased protease activity 22, 28 and 30% respect to control while Cd and Hg increased this activity in 23 and 27%. In Zn, Cu and Co treatments protease activity remained similar to control treatment. These results indicate that different proteases are involved in plant defence against metal toxicity. However, the identification of specific oxidized proteins involved in this process and the metal effect on class specific proteases should provide greater information

Driven Assembly of Lignin into Microcapsules for Storage and Delivery of Hydrophobic Molecules

Oil-filled microcapsules of kraft lignin were synthe- sized by first creating an oil in water emulsion followed by a high- intensity, ultrasound-assisted cross-linking of lignin at the water/oil interface. The rationale behind our approach is based on promoting documented lignin hydrophobic interactions within the oil phase, followed by locking the resulting spherical microsystems by covalent cross-linking using a high intensity ultrasound treatment. As further evidence in support of our rationale, confocal and optical microscopies demonstrated the uniformly spherical morphology of the created lignin microparticles. The detailed elucidation of the cross-linking processes was carried out using gel permeation chromatography (GPC) and quantitative 31P NMR analyses. The ability of lignin microcapsules to incorporate and release Coumarin-6 was evaluated in detail. In vitro studies and confocal laser scanning microscopy analysis were carried out to assess the internalization of capsules into Chinese hamster ovary (CHO) cells. This part of our work demonstrated that the lignin microcapsules are not cytotoxic and readily incorporated in the CHO cells

Effect of different metals on protease activity in sunflower cotyledons

Proteases are crucial for living cells and play a role in plant cell adaptation to environmental conditions. Oxidative stress produced oxidized proteins which are selectively degraded by proteases. To understand the role of proteolysis in response to metal stress, sunflower plants (a plant suitable for phytoremediation) were treated with 100 μM of CdCl2, CuCl2, AlCl3, CoCl2, PbCl2, CrCl3, NiCl2, HgCl2 or ZnCl2. Changes in protease activity, gelatinase profile and protein oxidation were examined in sunflower cotyledons. Our results indicate that this tissue has mainly acid proteases belonging to different classes. Although all metals (except Zn) increased protein oxidation (62, 57, 112, 74, 74, 68, 64 and 40% for Pb, Al, Ni, Cd, Hg, Co, Cr and Cu over the control), they altered proteolysis in different ways. Pb, Al and Ni treatment decreased protease activity 22, 28 and 30% respect to control while Cd and Hg increased this activity in 23 and 27%. In Zn, Cu and Co treatments protease activity remained similar to control treatment. These results indicate that different proteases are involved in plant defence against metal toxicity. However, the identification of specific oxidized proteins involved in this process and the metal effect on class specific proteases should provide greater information