Related Experiment Video
Updated: Jun 25, 2026
11:05
Analysis of Oxidative Stress in Zebrafish Embryos
Published on: July 7, 2014
Peroxisomes and reactive oxygen species, a lasting challenge
Sabine Angermüller1, Markus Islinger, Alfred Völkl
1Department of Anatomy and Cell Biology II, University of Heidelberg, Im Neuenheimer Feld 307, 69120 Heidelberg, Germany.
Histochemistry and Cell Biology
|February 19, 2009
Summary
Peroxisomes are key to oxygen metabolism, housing enzymes like catalase and D-amino acid oxidase. Studies reveal varied enzyme distribution within rat hepatocytes, highlighting peroxisome complexity.
Area of Science:
- Cell Biology
- Biochemistry
- Organelle Function
Background:
- Peroxisomes (PO) are central to oxygen metabolism, generating and scavenging hydrogen peroxide (H2O2).
- Catalase, a key peroxisomal enzyme, aids in organelle visualization and research.
- Enzyme activity and protein concentration vary within rat peroxisomes, even in adjacent cells.
Purpose of the Study:
- To investigate the distribution and activity of key enzymes within peroxisomes.
- To understand the role of peroxisomal enzymes in cellular oxygen metabolism.
- To explore the localization of D-amino acid oxidase, urate oxidase, xanthine oxidase, and CuZn superoxide dismutase.
Main Methods:
- Enzyme activity assays (e.g., D-amino acid oxidase, urate oxidase, xanthine oxidase).
- Histochemical staining (e.g., 3,3'-diamino-benzidine for catalase).
- Microscopic examination of enzyme localization within rat hepatocytes.
Main Results:
- D-amino acid oxidase activity is higher in kidney than liver, and in periportal over pericentral hepatocytes.
- Enzyme distribution is heterogeneous within peroxisomes, with some concentrated in the matrix or core.
- Urate oxidase and xanthine oxidase are found in peroxisomal cores, while CuZn superoxide dismutase is confirmed as a peroxisomal protein.
Conclusions:
- Peroxisomal enzyme distribution is highly specific and varies across tissues and cell types.
- Enzyme localization within peroxisomes (matrix, core, membrane association) impacts cellular function.
- Further research into peroxisomal enzyme roles is warranted, particularly concerning H2O2 metabolism.
Related Concept Videos
01:24Peroxisomes
Peroxisomes are specialized organelles present in fungi, plant, and animal cells. It can vary in number, size, morphology, and activity depending on the type of tissue and the nutritional state of the cell. For example, cells with active lipid metabolism, such as adipocytes, neurons, and hepatocytes, have more peroxisomes than other cells in the body. Besides their primary role in breaking down complex organic molecules, peroxisomes can also synthesize specific macromolecules and participate in...
01:30Peroxisomes
Peroxisomes and mitochondria are two important oxygen-utilizing organelles in eukaryotic cells. Mitochondria carry out cellular respiration—the process that converts energy from food into ATP. Peroxisomes carry out a variety of functions, primarily breaking down different substances, such as fatty acids.The peroxisome is a single membrane-bound cellular organelle that can perform several different functions, including lipid metabolism and chemical detoxification. The enzymes within peroxisomes...
01:24Peroxisomes
Peroxisomes are specialized organelles present in fungi, plant, and animal cells. It can vary in number, size, morphology, and activity depending on the type of tissue and the nutritional state of the cell. For example, cells with active lipid metabolism, such as adipocytes, neurons, and hepatocytes, have more peroxisomes than other cells in the body. Besides their primary role in breaking down complex organic molecules, peroxisomes can also synthesize specific macromolecules and participate in...
01:20Radical Autoxidation
The oxidation of an organic compound in the presence of air or oxygen is called autoxidation. For example, cumene reacts with oxygen to form hydroperoxide. Autoxidation involves initiation, propagation, and termination steps. Many organic compounds are susceptible to autoxidation—especially ethers in the presence of oxygen, which form hydroperoxides. Even though this reaction is slow, old ether bottles contain small amounts of peroxide, which leads to laboratory explosions during ether...
01:29Oxygen Requirements and Growth Patterns
Microorganisms exhibit diverse oxygen requirements and growth patterns driven by their metabolic strategies and environmental adaptations. Oxygen, while essential for many organisms, can also be toxic under certain conditions, shaping how microorganisms grow and survive.Oxygen Requirements of MicroorganismsMicroorganisms are classified based on their ability to use or tolerate oxygen:● Obligate aerobes like Mycobacterium tuberculosis need oxygen for energy production, as it serves as the...
01:27Protein Import into the Peroxisomes
Cells contain membrane-bound organelles called peroxisomes that oxidize organic molecules by transferring hydrogen atoms to oxygen, producing hydrogen peroxide. Peroxisomes enzymatically convert the released hydrogen peroxide into water and oxygen.
Peroxisomal Protein Import:
Peroxisomes lack the genetic machinery required to code for their own proteins. Hence, most peroxisomal membrane, lumenal and transmembrane proteins are synthesized in the cytoplasm or ER and transported to the peroxisome...
Peroxisomal Protein Import:
Peroxisomes lack the genetic machinery required to code for their own proteins. Hence, most peroxisomal membrane, lumenal and transmembrane proteins are synthesized in the cytoplasm or ER and transported to the peroxisome...