Native Gels (native + gel)

Distribution by Scientific Domains

Terms modified by Native Gels

  • native gel electrophoresis

  • Selected Abstracts


    Cadmium Enhances Generation of Hydrogen Peroxide and Amplifies Activities of Catalase, Peroxidases and Superoxide Dismutase in Maize

    JOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 1 2008
    P. Kumar
    Abstract Maize (Zea mays L. cv. 777) plants grown in hydroponic culture were treated with 50 ,m CdSO4. Growth and metabolic parameters indicative of oxidative stress and antioxidant responses were studied in leaves of plants treated with Cd. Apart from increasing lipid peroxidation and H2O2 accumulation, supply of Cd suppressed growth, fresh and dry mass of plants and decreased the concentrations of chloroplastic pigments. The activities of catalase (CAT; EC 1.11.1.6), peroxidase (POD; EC 1.11.1.7), ascorbate peroxidase (APX; EC 1.11.1.11) and superoxide dismutase (SOD; EC 1.15.1.1) were increased in plants supplied 50 ,m Cd. Localization of activities of isoforms of these enzymes (POD, APX and SOD) on native gels also revealed increase in the intensities of pre-existing bands. Stimulated activities of CAT, POD, APX and SOD in maize plants supplied excess Cd do not appear to have relieved plants from excessive generation of reactive oxygen species (ROS). It is, therefore, concluded that supply of 50 ,m Cd induces oxidative stress by increasing production of ROS despite increased antioxidant protection in maize plants. [source]


    Excess nickel,induced changes in antioxidative processes in maize leaves

    JOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 6 2007
    Praveen Kumar
    Abstract Maize (Zea mays L. cv. 777) plants grown in hydroponic culture were treated with 100 µM NiSO4 (moderate nickel (Ni) excess). In addition to growth parameters, metabolic parameters representative of antioxidant responses in leaves were assessed 24 h and 3, 7, and 14 d after initiating the Ni treatment. Extent of oxidative damage was measured as accumulation of malondialdehyde and hydrogen peroxide in leaves 7 and 14 d after treatment initiation. Apart from increasing membrane-lipid peroxidation and H2O2 accumulation, excess supply of Ni suppressed plant growth and dry mass of shoots but increased dry mass of roots and decreased the concentrations of chloroplastic pigments. Excess supply of Ni, though inhibited the catalase (EC 1.11.1.6) activity, increased peroxidase (EC 1.11.1.7), ascorbate peroxidase (EC 1.11.1.11), and superoxide dismutase (EC 1.15.1.1) activities. Localization of isoforms of these enzymes (peroxidase, ascorbate peroxidase, and superoxide dismutase) on native gels also revealed increases in the intensities of pre-existing bands. Enhanced activities of peroxidase, ascorbate peroxidase, and superoxide dismutase, however, did not appear to be sufficient to ameliorate the effects of excessively generated reactive oxygen species due to excess supply of Ni. [source]


    Characterisation of Zea mays L. plastidial transglutaminase: interactions with thylakoid membrane proteins

    PLANT BIOLOGY, Issue 5 2010
    A. Campos
    Abstract Chloroplast transglutaminase (chlTGase) activity is considered to play a significant role in response to a light stimulus and photo-adaptation of plants, but its precise function in the chloroplast is unclear. The characterisation, at the proteomic level, of the chlTGase interaction with thylakoid proteins and demonstration of its association with photosystem II (PSII) protein complexes was accomplished with experiments using maize thylakoid protein extracts. By means of a specific antibody designed against the C-terminal sequence of the maize TGase gene product, different chlTGase forms were immunodetected in thylakoid membrane extracts from three different stages of maize chloroplast differentiation. These bands co-localised with those of lhcb 1, 2 and 3 antenna proteins. The most significant, a 58 kDa form present in mature chloroplasts, was characterised using biochemical and proteomic approaches. Sequential fractionation of thylakoid proteins from light-induced mature chloroplasts showed that the 58 kDa form was associated with the thylakoid membrane, behaving as a soluble or peripheral membrane protein. Two-dimensional gel electrophoresis discriminated, for the first time, the 58-kDa band in two different forms, probably corresponding to the two different TGase cDNAs previously cloned. Electrophoretic separation of thylakoid proteins in native gels, followed by LC-MS mass spectrometry identification of protein complexes indicated that maize chlTGase forms part of a specific PSII protein complex, which includes LHCII, ATPase and pSbS proteins. The results are discussed in relation to the interaction between these proteins and the suggested role of the enzyme in thylakoid membrane organisation and photoprotection. [source]


    Expression and activity of isoenzymes of superoxide dismutase in wheat roots in response to hypoxia and anoxia

    PLANT CELL & ENVIRONMENT, Issue 2 2000
    S. Biemelt
    ABSTRACT We investigated the effects of hypoxia, anoxia and reaeration on enzymatic activity and expression of superoxide dismutase (SOD) isoforms in wheat roots (Triticum aestivum L.). Neither hypoxia nor subsequent re-aeration caused significant changes in SOD isoenzyme pattern compared with aerated controls. However, anoxia led to the appearance of additional activity bands of SOD in native gels resulting in an increase in total activity. Additional isoformic bands remained also apparent in the following recovery period. Re-aeration following both hypoxia and anoxia resulted in an increased content of hydrogen peroxide in roots. SOD transcript and protein levels were only slightly altered in response to hypoxia. Although SOD mRNA levels were diminished, protein content of different SOD isoforms increased with duration of anoxia. Incubation of roots with cycloheximide revealed that the additional activity bands and higher SOD protein content under anoxia were not due to de novo synthesis. Crude subcellular fractionation experiments implied that the anoxia-responsive SOD isoforms might be plastid-associated. We suggest that SOD is a very stable enzyme which, under anoxia, accumulates relative to total protein content and remains active even after protein modification under severe environmental stress conditions. [source]