Microbodies

Microbodies were discovered in the proximal convoluted tubule of a mouse’s kidney in 1954, as reported by biologist Rhodin. It was discovered within the tubule’s ultrastructure. Porter and Caulfield later reported similar findings in plants in 1958. In eukaryotic cells, microbodies are now recognised as intracellular respiratory organelles. 

Microbodies from all tissues are morphologically similar and have the same enzymatic characteristics; however, their metabolic pathways inside this subcellular compartment differ depending on the tissue. Microbodies (peroxisomes and glyoxysomes) were only recently recognised as subcellular constituents, and biologists were only able to determine their relevance by the end of the 1960s.

Microbodies are a diverse set of organelles that are found in almost every cell’s cytoplasm. They are generally spherical and are bound by a single membrane. Microbodies exist in a variety of shapes and sizes, including lysosomes, although peroxisomes are the most frequent. Peroxisomes can be found in one or more cells in all eukaryotes. Christian de Duve, a Belgian scientist who also discovered lysosomes, was the first to discover the organelles.

Microbodies 

• Microbodies are minute vesicles, membrane-bounded, containing a variety of enzymes.
• Spherosomes, peroxisomes, and glyoxysomes are all types of microbodies.
• Plants only have spherosomes and glyoxysomes, whereas peroxisomes are found in both plants and animals.
• Each microbody specifically carries out a particular function.

Spherosomes

• Plant lysosomes are a common name for sphaerosomes.
• The function of sphaerosomes in fat synthesis and storage.
• They can only be found in the cells of plants.
• These are mostly present in cells that are involved in fat synthesis and storage, as the endosperm of oily seeds.
• The lipids make up 98 percent of a sphaerosome, while the proteins make up the remaining 2%.
• Some proteins are likely enzymatic and play a role in lipid synthesis.
• They emerge from the endoplasmic reticulum and are encased in a single, half-unit membrane made up of a phospholipid monolayer with polar heads facing the cytoplasm and hydrophobic tails towards the inner side.
• Some tissues, such as tobacco endosperm and maize root-tip have sphaerosomes that contain hydrolytic enzymes and hence have lysosomal activity.

Peroxisomes

• Christian de Duve classified peroxisomes as organelle in 1965.
• Plant and animal cells both contain these microbodies. 
• Organelles such as the endoplasmic reticulum, mitochondria, and chloroplasts are found near it.
•  It is found in all eukaryotic cells and is particularly abundant in liver and kidney cells. The endoplasmic reticulum produces 70-100 peroxisomes, which are found in the photosynthetic cell. 
• The outer membrane protects these structures, and the internal matrix can be granular or contain equally spaced fibrils. 
• Oxidative enzymes such as urate oxidase, hydroxy acid oxidase, and hydroxy acid oxidase are found in these microbodies. It is necessary to use molecular oxygen. 
• Also, the shape, size, and diameter of the peroxisomes are variables.
• The process generates hydrogen peroxide, which is quickly metabolised by the body.

Functions of peroxisomes

• Peroxisomes metabolise a variety of harmful chemicals in animal cells, including nitrite, phenols, formaldehyde, formic acid, methanol, and ethanol. Within the liver cells, 25% of the alcohol consumed is detoxified. 
•  Xenobiotics are compounds that cannot be broken down by normal enzymes and must instead be broken down inside peroxisomes.
•  Peroxisomes break down long and branched-chain fatty acids like prostaglandins. 
• This organelle transforms fixed nitrogen into ureids, which are then transported to the root nodules. Plant peroxisomes, which are located in photosynthetic cells and are connected with the chloroplast and mitochondria, are responsible for photorespiration. 
• Glycolate is taken up by peroxisomes from chloroplasts and oxidised with oxygen to form glyoxylate. As a byproduct of the procedure, hydrogen peroxide is created. Glyoxylate is converted to glycine, an amino acid. 

Glyoxysomes

• These are microbodies that contain enzymes for fatty acid oxidation as well as the glyoxylate pathway.
• Breidenbach first discovered this in 1967.
• These organelles are thought to be a subtype of peroxisomes.
• These are the largest microbodies and can only be found in plants.

Detailed Explanation

• Glyoxysomes are structures found in the developing fatty seeds (castor, groundnut seed, and so on) and the cells of some fungi until the stored fat is eaten.
• Glyoxysomes contain enzymes and have a single covering membrane.
• Acetyl CoA is produced when fatty acids are oxidised.
• In the glyoxylate cycle, the latter is digested to produce carbs.
• After accomplishing their role, glyoxysomes are transformed into peroxisomes.
• These structures emerge in senescent plant tissues for the breakdown and mobilisation of lipids.

Micro body Expression: Disorder

• Peroxisome Inborn Errors/Peroxisome
• Biogenesis Disorders in Humans 

There are generally two types of peroxisomal diseases – Peroxisome biogenesis disorders (abbreviated as PBDs) peroxisomal single enzyme deficits (abbreviated as PSEs). These disorders affect the development of peroxisomes within the cell (functional disorder in peroxisomes).

Conclusion

Microbodies, commonly known as cytosomes, are various types of bodies found in the cytosol. A microbody is a small spherical vesicle with a diameter of 0.2 to 1.5 micrometres. Microbodies are found in a cell’s cytoplasm and are microscopic. They are encased in a single phospholipid bilayer membrane. They contain a matrix of intracellular material that includes enzymes and other proteins, but they don’t appear to possess any genetic material that would allow them to self-replicate.