Peroxisomes: Structure and Function of Peroxisomes

Peroxisomes are the membrane bound organelle that are found in the cytoplasm of eukaryotic cells. These organelles are responsible for the oxidation of biomolecules. Peroxisomes are also found in the liver cells of animals and plants and are known as peroxisome reticulum. In this article, we will discuss the Peroxisomes, its structure and function. 

Peroxisomes 

Peroxisomes are small spherical sized organelles that are enclosed by cell membranes and mostly found in eukaryotic cells. These peroxisomes consist of oxidative enzymes and digestive enzymes. These are also found in the liver cells of animals and plants and known as peroxisome reticulum.

The peroxisomes are required for synthesizing phospholipids that are important for nerve cell myelination. They do not have DNA and ribosomes and are self-replicating organelles present in the eukaryotic cells.

Structure of Peroxisomes

The peroxisomes are small spherical shaped organelles and are formed by many different types of enzymes, such as digestive enzymes, oxidative enzymes and phospholipid bilayer. Peroxisomes can be found in different shapes, sizes and numbers depending upon the energy required by the cells. 

The synthesis of the cell membranes and their proteins and lipids plays an important role in the formation of peroxisomes. In this process, the imports of the proteins are required. The proteins and lipids are imported from the cytosol and cell cytoplasm to produce the peroxisomes.

Structure of Peroxisomes

Functions of Peroxisomes

The main functions of peroxisomes are-

• The peroxisomes take part in different oxidative processes. The enzymes found in peroxisomes oxidize some specific molecules like amino acids and fatty acids to produce hydrogen peroxide.
• Peroxisomes help in breaking down the organic molecules to form hydrogen peroxide. It also convert the hydrogen peroxide (H₂O₂) to form water (H₂O) and oxygen (O₂) with the help of catalase enzymes
• The peroxisomes facilitate seed germination and photosynthesis in the plants.
• It degrades the purines, amino acids, polyamines and uric acid oxidase.
• Peroxisomes help in the progression of the phagocytosis to activate the innate immune signaling and promotes the survival of microbial challenges.
• Peroxisomes help in bioluminescence. In the bioluminescent process, an enzyme such as luciferase, oxidizes certain small molecule substrate to produce light
• It has an important role in the plant cells. It recycle the phosphoglycolate carbon at the time of photorespiration process of plants

Things to Remember Based on Peroxisomes 

• The Peroxisomes are cell membrane bound organelles whose size is 0.2-1.5 µm in diameter. 
• The size of peroxisomes differs in both plants and animal cells.
• These are found in eukaryotic cells of plants and animals.
• They can be present in the form of individual micro-peroxisomes or peroxisome reticulum (a network of interconnected tubules).
• Peroxisomes can be found in different shapes, sizes and numbers depending upon the energy required by the cells. 
• The enzymes found in peroxisomes oxidize some specific molecules like amino acids and fatty acids to produce hydrogen peroxide.
• It degrades the purines, amino acids, polyamines and uric acid oxidase.