Which Organelle Among The Following Has Oxidative Enzymes?

Peroxisomes are membrane-bound organelles found in the cytoplasm of eukaryotic cells, which play a crucial role in the oxidation of specific biomolecules. They contain oxidases that facilitate chemical oxidation reactions of various substances like toxins, amino acids, and fatty acids within their peroxisomal matrix. These organelles are responsible for lipid production and oxidation reactions within the cell.

The correct option is B. Lysosomes. Peroxisomes contain at least 50 different enzymes involved in various biochemical pathways in different types of cells. They are responsible for lipid production and oxidation reactions within the cell. They also detoxify poisons and have various functions.

Mitochondria is responsible for the process of respiratory organelle where oxidation of stored food material takes place. Lysosomes, on the other hand, are involved in protein destruction, recycling, and security. They contain oxidase enzymes that function in neutralizing harmful free radicals.

In summary, peroxisomes are a key organelle in eukaryotic cells that contain oxidative enzymes capable of oxidizing toxic substances. They are responsible for lipid production, oxidation reactions, and the removal of toxic substances from cells.

Which organelle contains enzymes necessary for oxidative?

Functions of Peroxisomes. Peroxisomes contain at least 50 different enzymes, which are involved in a variety of biochemical pathways in different types of cells. Peroxisomes originally were defined as organelles that carry out oxidation reactions leading to the production of hydrogen peroxide. Because hydrogen peroxide is harmful to the cell, peroxisomes also contain the enzyme catalase, which decomposes hydrogen peroxide either by converting it to water or by using it to oxidize another organic compound. A variety of substrates are broken down by such oxidative reactions in peroxisomes, including uric acid, amino acids, and fatty acids. The oxidation of fatty acids ( Figure 10. 25 ) is a particularly important example, since it provides a major source of metabolic energy. In animal cells, fatty acids are oxidized in both peroxisomes and mitochondria, but in yeasts and plants fatty acid oxidation is restricted to peroxisomes.

Figure 10. 25. Fatty acid oxidation in peroxisomes. The oxidation of a fatty acid is accompanied by the production of hydrogen peroxide (H 2 O 2 ) from oxygen. The hydrogen peroxide is decomposed by catalase, either by conversion to water or by oxidation of another organic (more…)

In addition to providing a compartment for oxidation reactions, peroxisomes are involved in lipid biosynthesis. In animal cells, cholesterol and dolichol are synthesized in peroxisomes as well as in the ER. In the liver, peroxisomes are also involved in the synthesis of bile acids, which are derived from cholesterol. In addition, peroxisomes contain enzymes required for the synthesis of plasmalogens —a family of phospholipids in which one of the hydrocarbon chains is joined to glycerol by an ether bond rather than an ester bond ( Figure 10. 26 ). Plasmalogens are important membrane components in some tissues, particularly heart and brain, although they are absent in others.

Which of the following are oxidative enzymes?

An oxidative enzyme is an enzyme that catalyses an oxidation reaction. Two most common types of oxidative enzymes are peroxidases, which use hydrogen peroxide, and oxidases, which use molecular oxygen. They increase the rate at which ATP is produced aerobically.

Oxidative enzymes are responsible for the browning of fruits like apples. When the surface of apples are exposed to the oxygen in the air, the oxidative enzymes like polyphenol oxidase and catechol oxidase oxidize the fruit (electrons are lost to the air). Such browning can be prevented by cooking the fruit or lowering the pH (which destroys, inactivates, or denatures the enzyme) or by preventing oxygen from getting to the surface (such as by covering the fruit).

• ^ Eric J. Toone. Advances in Enzymology and Related Areas of Molecular Biology, Protein Evolution (Volume 75 ed.). Wiley-Interscience. ISBN 0471205036.
• ^ Nicholas C. Price
• Lewis Stevens. Fundamentals of Enzymology: The Cell and Molecular Biology of Catalytic Proteins (Third ed.). USA: Oxford University Press. ISBN 019850229X.

Which organelles contain oxidative enzymes?

Peroxisomes are found in all eucaryotic cells. They contain oxidative enzymes, such as catalase and urate oxidase, at such high concentrations that in some cells the peroxisomes stand out in electron micrographs because of the presence of a crystalloid core (Figure 12-31).

Peroxisomes differ from mitochondria and chloroplasts in many ways. Most notably, they are surrounded by only a single membrane, and they do not contain DNA or ribosomes. Like mitochondria and chloroplasts, however, peroxisomes are thought to acquire their proteins by selective import from the cytosol. But because they have no genome, all of their proteins must be imported. Peroxisomes thus resemble the ER in being a self-replicating, membrane-enclosed organelle that exists without a genome of its own.

Because we do not discuss peroxisomes elsewhere, we shall digress to consider some of the functions of this diverse family of organelles, before discussing their biosynthesis. Peroxisomes are found in all eucaryotic cells. They contain oxidative enzymes, such as catalase and urate oxidase, at such high concentrations that in some cells the peroxisomes stand out in electron micrographs because of the presence of a crystalloid core ( Figure 12-31 ).

Figure 12-31. An electron micrograph of three peroxisomes in a rat liver cell. The paracrystalline electron-dense inclusions are composed of the enzyme urate oxidase. (Courtesy of Daniel S. Friend.)

Which cell organelles have abundance of oxidizing enzymes?

The cell organelles having abundance of oxidizing enzymes is mitochondria. Mitochondria supply most or the necessary biological energy through reduction of NADP. A dominant role for the mitochondria is the production of ATP.

Which cell organelle is considered to be rich in oxidative enzymes?

Mitochondria Mitochondria is the double membrane bound organelle which carries several enzymatic reactions such as Kreb’s cycle and oxidative phosphorylation.

Which of the following cell organelles possess oxidase enzymes?

The organelle in the cell that possesses oxidase enzymes which function in neutralizing harmful free radicals is the peroxisome. Peroxisomes, like lysosomes, are membrane-bound cellular organelles that contain mostly enzymes. They perform several functions, such as lipid metabolism and chemical detoxification.

Where are oxidase enzymes found?

Oxidases are the main enzymes in peroxisomes, and oxidases account for about half of the total peroxisomes.

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Where are antioxidant enzymes found?

The antioxidant enzymes are represented by the family of superoxide dismutases (SOD) formed by Cu-Zn SOD or soluble SOD1 located in the cytosol, Mn-SOD or SOD2 located in the mitochondria, and extracellular, or SOD3.

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Does mitochondria contain oxidative enzymes?

Summary. The mitochondrion performs most cellular oxidations and produces the bulk of the animal cell’s ATP. The mitochondrial matrix contains a large variety of enzymes, including those that convert pyruvate and fatty acids to acetyl CoA and those that oxidize this acetyl CoA to CO 2 through the citric acid cycle. Large amounts of NADH (and FADH 2 ) are produced by these oxidation reactions.

The energy available from combining molecular oxygen with the reactive electrons carried by NADH and FADH 2 is harnessed by an electron-transport chain in the inner mitochondrial membrane called the respiratory chain. The respiratory chain pumps H + out of the matrix to create a transmembrane electrochemical proton (H + ) gradient, which includes contributions from both a membrane potential and a pH difference. The large amount of free energy released when H + flows back into the matrix (across the inner membrane) provides the basis for ATP production in the matrix by a remarkable protein machine—the ATP synthase. The transmembrane electrochemical gradient is also used to drive the active transport of selected metabolites across the mitochondrial inner membrane, including an efficient ATP-ADP exchange between the mitochondrion and the cytosol that keeps the cell’s ATP pool highly charged. The resulting high ratio of ATP to its hydrolysis products makes the free-energy change for ATP hydrolysis extremely favorable, allowing this hydrolysis reaction to drive a large number of the cell’s energy-requiring processes.

What are the oxidative enzymes in the mitochondria?

Oxidative phosphorylation occurs within the mitochondrial inner membrane, where four large multi-subunit enzyme complexes are located. The excessive formation of reactive oxygen species (ROS) and impairment of defensive antioxidant systems leads to oxidative stress, which is a condition associated with mitochondrial respiration. The deleterious effects of ROS on cellular biomolecules, including DNA, can disrupt mitochondrial function and contribute to cellular damage and death, leading to various disease processes. This review summarizes the most important findings implicated in mitochondrial oxidative stress in a wide variety of pathologies from Alzheimer disease (AD) to autoimmune type 1 diabetes.

Oxidative stress is an imbalance between the production and accumulation of ROS and the defense antioxidant systems. ROS, when produced excessively, become one of the main causes of cell and tissue damage, resulting from direct harmful action on biological structures such as proteins, lipids, and nucleic acids. Endogenous ROS are generated as by-products of oxygen metabolism, while exogenous oxidative stress can be evoked by environmental stressors such as ionizing radiation, UV, pollutants, cigarette smoke, heavy metals, and certain drugs. Chronic inflammatory processes in the organism aggravate oxidative stress and enhance the generation of ROS.

What cell organelles have enzymes?

Lysosomes are membrane-enclosed organelles that contain an array of enzymes capable of breaking down all types of biological polymers—proteins, nucleic acids, carbohydrates, and lipids. Lysosomes function as the digestive system of the cell, serving both to degrade material taken up from outside the cell and to digest obsolete components of the cell itself. In their simplest form, lysosomes are visualized as dense spherical vacuoles, but they can display considerable variation in size and shape as a result of differences in the materials that have been taken up for digestion ( Figure 9. 34 ). Lysosomes thus represent morphologically diverse organelles defined by the common function of degrading intracellular material.

Figure 9. 34. Electron micrograph of lysosomes and mitochondria in a mammalian cell. Lysosomes are indicated by arrows. (Visuals Unlimited/K. G. Murti.)

Lysosomal Acid Hydrolases. Lysosomes contain about 50 different degradative enzymes that can hydrolyze proteins, DNA, RNA, polysaccharides, and lipids. Mutations in the genes that encode these enzymes are responsible for more than 30 different human genetic diseases, which are called lysosomal storage diseases because undegraded material accumulates within the lysosomes of affected individuals. Most of these diseases result from deficiencies in single lysosomal enzymes. For example, Gaucher’s disease (the most common of these disorders) results from a mutation in the gene that encodes a lysosomal enzyme required for the breakdown of glycolipids. An intriguing exception is I-cell disease, which is caused by a deficiency in the enzyme that catalyzes the first step in the tagging of lysosomal enzymes with mannose-6-phosphate in the Golgi apparatus (see Figure 9. 25 ). The result is a general failure of lysosomal enzymes to be incorporated into lysosomes.