What does ascorbate peroxidase do in plants?
Ascorbate peroxidase (APX) is a key antioxidant enzyme of such scavenging systems. It catalyses the conversion of H2O2 into H2O, employing ascorbate as an electron donor. The expression of APX is differentially regulated in response to environmental stresses and during normal plant growth and development as well.
How do you calculate ascorbate peroxidase activity in plants?
The enzyme activity can be calculated according to the following equation: Enzyme activity (Units/L) = (ΔAbs × Total assay volume) / ( Δt x ε x l x Enzyme sample volume). extinction coefficient of substrates in units of M-1 cm-1), and l is the cuvette diameter (1cm).
What is sod in plants?
Superoxide dismutases (SODs) are metal-containing enzymes that catalyze the dismutation of superoxide radicals to oxygen and hydrogen peroxide. In plants, three forms of the enzyme exist, as classified by their active site metal ion: copper/zinc, manganese, and iron forms.
What does catalase do in plants?
In plants, catalase scavenges H2O2 generated during mitochondrial electron transport, β-oxidation of the fatty acids, and most importantly photorespiratory oxidation (6). Accumulating evidence indicates that catalase plays an important role in plant defense, aging, and senescence.
What is the function of ascorbate peroxidase?
Ascorbate peroxidase is a key enzyme regulating ROS levels acting in different subcellular compartments (Figure 2). The expression of APX encoding genes is differentially modulated by several abiotic stresses in different plant species.
What is the reaction of peroxidase?
Peroxidases, also known as catalases, are also an oxidoreductase class of enzymes, which catalyze oxidoreduction reactions. The peroxidase enzyme catalyzes the decomposition of hydrogen peroxide into water and molecular oxygen (see illustration).
Why is peroxidase important in plants?
Peroxidases are a family of isozymes found in all plants; they are heme-containing monomeric glycoproteins that utilize either H(2)O(2) or O(2) to oxidize a wide variety of molecules. These important enzymes are used in enzyme immunoassays, diagnostic assays and industrial enzymatic reactions.
What good is SOD?
SOD is used in cosmetics and personal care products as an anti-aging ingredient and antioxidant due to its ability to reduce free radical damage to the skin, therefore preventing wrinkles, fine lines, and age spots, and it also helps with wound healing, softens scar tissue, protects against UV rays, and reduces other …
What is the function of peroxidase?
Peroxidases, also known as catalases, are also an oxidoreductase class of enzymes, which catalyze oxidoreduction reactions. The peroxidase enzyme catalyzes the decomposition of hydrogen peroxide into water and molecular oxygen (see illustration). Catalase is a haem-containing enzyme.
How do you test catalase activity in plants?
The principally common method for measuring catalase activity is the UV spectrophotometric method, which depends on monitoring the change of 240 nm absorbance at high levels of hydrogen peroxide solution (≥30 mM).
