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Microbodies:
A microbody can thus be defined as a cytoplasmic organelle that is more or less
globular in shape
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They are considered as containers for metabolic activity
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Some of them include peroxisomes, glyoxysomes,
glycosomes, and Woronin bodies
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These are also called
cytosomes
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2-1
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Microbodies can be seen in the cytoplasm of a cell, but they will be
visible only through an electron microscope
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Classification:
The enzymes present in microbodies take part in the preparatory or intermediate stages of
various biochemical reactions happening within the cell
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Generally, detoxification of peroxides and
photorespiration in plants are major functions of microbodies
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Some important microbodies include:
i) Glyoxysomes
ii) Peroxisomes
iii) Glycosomes and
iv) Woronin bodies
1
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They are mainly involved in the metabolism of fatty acids along with
other metabolites
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Peroxisomes are single membrane-bound bodies
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The
membrane proteins are critical for various functions including import of proteins into
the organelles and proliferation
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2
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Be it germinating seeds of plants
or filamentous fungi, these microbodies will be there
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Peroxisomes are

responsible for f b-oxidation (break down fats and produce Acetyl-CoA) and other
important pathways including amino acid and bile acid metabolism, along with
oxidation or detoxification of various harmful compounds in the liver like alcohol
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Some of them
are as follows:
In animal cells, microbodies can be found in the form of peroxisomes
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They also contain the enzymes
catalase, oxidase and peroxidase for the breakdown of hydrogen peroxide (a harmful
byproduct of other chemical reactions) to water molecules
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They also possess crucial enzymes for the Glyoxylate cycle
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Oxidative enzymes, like catalase, D-amino acid oxidase, and uric acid oxidase (except
in humans) are found in peroxisomes
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II
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Peroxisomes bring about β-oxidation of very long chain fatty acids and  α-oxidation of
branched chain fatty acids to break down fatty acids
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Glyoxysomes help in the synthesis of sugar by the process of gluconeogenesis
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In plant cells, these microbodies may appear to be dividing or may be found in an
interconnected or tubular state
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They follow the reaction:
2H₂O₂ = 2H₂O + O₂
VI
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It is found to occur to remove this toxic
chemical from the blood
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However, glyoxysomes are predominantly found in plants and filamentous fungi (mold)
cells, while peroxisomes are characteristic to animal cell type
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Peroxisomes
in turn contain enzymes (such as catalase, peroxidase, etc
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3
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A few species of protozoa, found in the human
pathogenic trypanosomes, responsible for sleeping sickness, and Chagas's disease, and
Leishmania possess glycosomes
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Glycosomes possess peroxisomal enzymes and glycolysis enzymes
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Woronin Body:
The peroxisome derived, dense core microbody protected by a double-layered membrane is
the woronin body
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It is
found near the septae dividing hyphal compartments in filamentous Ascomycota
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It prohibits the
loss of cytoplasm from the sites of injury
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They can be visualized with a light microscope in some
species
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Some inborn errors are common such as  Galactosemia,
while others are rare in occurrence
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In humans, however, the
peroxisome can develop biogenesis disorders leading to a large number of secondary
disorders,
for
example
the  Zellweger
spectrum
disorders
(ZSD)  can
cause hepatomegaly, abnormal bone calcification, etc

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