Proteins are subject to continuous quality control for optimal proteostasis. The knowledge of peroxisome quality control systems is still in its infancy. Here we show that peroxisomes contain a member of the Lon family of proteases (Pln). We show that Pln is a heptameric protein and acts as an ATP-fueled protease and chaperone. Hence, Pln is the first chaperone identified in fungal peroxisomes....

The catalase within normal, intact human erythrocytes was completely inactivated with amino triazole. The rate of 14CO2 evolution, when the cells were subsequently incubated with 14C-labeled glucose, provided a measure of the rate at which NADPH was being oxidized by the glutathione peroxidase/reductase system for the disposal of H2O2. This rate was determined in control cells and in catalase-i...

Deficiency of nitrogen may lead to decrease in yield and yield potential of crop plants. An experiment was done under glasshouse conditions in order to investigate nitrogen levels and salicylic acid interaction on some physiologic traits of borage (Borago officinials L.). In this experiment various levels of nitrogen (including; 27.5, 55, 110, 220 and 330 mg/L from ammonium nitrate) and salicyl...

The physical properties and activities of the purified catalase-peroxidase hydroperoxidase I (HPI) of Escherichia coli (EcHPI) and HPI with a carboxyl-terminal extension of Mycobacterium tuberculosis (MtHPI-e) are compared to those of commercial preparations of horseradish peroxidase (HRP). The catalase-peroxidase proteins had similar absorption spectra and differed primarily in that MtHPI-e ha...

In order to understand the response of tobacco to salt stress, antioxidant enzyme activities, plant biomass and ion content were analyzed in two oriental tobacco genotypes (Basma 31 and SPT 406). Tobacco plants were exposed to 0, 50, 100, 150 and 200 mM NaCl for 12 days. The fresh and dry weight as well as shoot and root length of Basma 31 were greater than those of SPT 406 under increasing sal...

The activities of catalase, peroxidase, and polyphenoloxidase were studied in attached and detached rice (Oryza sativa L. cv. Ratna) leaves. Catalase activity decreased while peroxidase and polyphenoloxidase activities increased during senescence of both attached and detached rice leaves. Kinetic (5 mum) and benzimidazole (1 mm), which are known to delay the senescence of detached rice leaves, ...

We examined 40 strains of Legionella for reduced-oxygen scavenging enzymes. Using a simple reaction chamber with a Swinney filter for the Beers and Sizer assay, we determined the catalase activity of live cells grown on buffered charcoal-yeast extract agar. For 29 strains of Legionella pneumophila, the apparent first-order rate constants for catalase ranged from 0.000 to 0.005. Similarly, low v...

the aims of this study were to assess the effects of drought stress on peroxidase (pod), superoxide dismutase (sod) and catalase (cat) activities as well as free proline content and growth parameters of pistacia khinjuk seedlings under drought stress. therefore, the one-year seedlings of pistacia khinjuk subjected to water stress (25%, 50%, 75%, and 100% field capacity) for 8 months in greenhou...

the role of zinc (zn) in enhancing defense capacity of several plants against salinity has been demonstrated but there is limited information on the impact of zn nutrition on alleviating salinity-induced oxidative damage in olive. one-year-old seedlings of two varieties of olive (olea europaea l. cvs. frontoio and conservolea) supplied with three zn levels (0, 1 and 5 mm in the form of znso4.7h...

potato (solanum tuberosum l.) auxiliary buds c.v. white desiree were cultured in ms medium containing 0, 50, 100, 150 and 200 μm concentrations of silver thiosulfate (sts) under in vitro condition. after eight weeks, the effect of silver ions (ag+) in the form of silver thiosulfate complex (sts), as an ethylene action inhibitor, on chlorophyll contents of leaves, ascorbate peroxidase, guaiacol ...