Peroxisomes are single-membrane organelles that contain oxidative enzymes. They play important roles in breaking down fatty acids and toxic metabolites. Peroxisomal disorders can result from defects in peroxisome biogenesis or metabolism. Two examples are X-linked adrenoleukodystrophy, which causes a buildup of very long chain fatty acids, and Zellweger syndrome, the most severe peroxisome biogenesis disorder characterized by defects in development and metabolism.

1. PEROXISOME
Introduction
Metabolic function
Peroxisomal Disorder
REFERENCES
 Lauralee Sherwood Human Phsiology
 Slide Share
 N
europathology
Made By: KASHAF

2. FATIMA IQBAL

3. PEROXISOME
HISTORY: Peroxisome was firstdiscovered by J.Rhodin in 1954 & was
officially considered as a cell organelle in 1967 by Christian De Duve.
INTRODUCTION:
 The peroxisome has a single
membrane which encloses the
peroxisomal matrix. The
peroxisomal membrane is a lipid
bilayerwith embedded
peroxisomal membrane proteins.
 They are rounded or oval in shape,
roughly arrange & ranges in size
from 0.2 to 1.7μm.
 Inside the vesicles many different
type of enzymes (nearly 50)are present.
 Number & size of peroxisomes vary, depending on the environment.
 The organ where the peroxisomes are more abundantis Liver.
 They contains oxidative enzymes likecatalase,urate oxidase, D-
aminoacid oxidase.
HOW THEY ARE DIFFER
FROM THE LYSOSOMES?
 They are similarphysicallyto
lysosome but are mainly
differentiated from lysosomes by
two ways.
 Firstly they are believed to be
formed by self-replication (Or
perhaps by budding off from the
Smooth endoplasmicreticulum)rather than the Golgi apparatus.

4.  Secondly, peroxisomes hold on to enzymes thatrequires oxygen
(oxidative enzyme) whereas the lysosomes have enzymes that works
in oxygen poor areas & lower pH.
OXIDATIVE ENZYMES: As the enzymatic name implies that they are
are the enzymes that use oxygen (O2) to strip hydrogen from certain organic molecules.
This reaction of peroxisomes plays a vital role to detoxify various waste products
within the cell or foreign toxic compounds. That has entered the cell such as alcohol
consumed in beverages.
MAJOR METABOLIC FUNCTION OF PEROXISOME IN HUMANS
 Important function includes the breakdown of hydrogen peroxide (H2O2),
a potentially dangerous product of fatty acid oxidation. It is catalyzed by
the enzyme catalase.
 They play role in digesting alcohol (ethanol), as they do this job so these
structure are found to be more abundant in liver rather than most other
cells of the body.
 There membrane contains digestive enzymes for breaking down of toxic
materials in the cell.
 They are very well known for digesting excess fatty acids by oxidation.
 The products of VLCFA (very long chain fatty acid) beta oxidation are
used for biosynthesis of cholesterol, bile acids, and other compounds.
 Also performs the function of breakdown of excess purine into uric acid.
PEROXISOMAL DISORDERS
All peroxisomal disorders except X-linked adrenoleukodystrophy are autosomal
recessive. As in other genetic disorders, several mutations of each gene are seen,
some of them severe and others milder. The unique biogenesis of peroxisomes
and multiple interactions of peroxisomal genes explain the genetic and
phenotypic complexity of peroxisomal disorders.

5. 1) ADRENOLEUKODYSTROPHY:
WHAT IS IT?
 It is a X linked disorder caused by
mutation of a gene that encodes the
peroxisomal membrane protein, the
ALD protein.
 This disorder results in the building of
very long chain fatty acids throughout
the body, mainly in the nervous
system, the testes & adrenal glands. As it is a X linked disorder so it
severely affects boys & men.
SYMPTOMS: Symptoms include:
o The muscle loss, stiffness, weakness or spasms
o Strabismus i.e. Visual axes cannotbe directed at the same direction
or some other visual disorders.
o Decrease in verbal communication.
o Nervous system detoriation
o Difficulty in controlling urine, loss of appetite, vomiting.
2) ZELLWEGER SYNDROME:
WHAT IS IT?
 This disease is related to Peroxisome Biogenesis Disorder (PBD), which is a
part of a larger group of diseases called
the leukodystrophies.
 These are inherited conditions that
damage the white matter of the brain &
also affect how the body metabolizes
particular substances in the blood &
organ tissues.
 It may cause due to defects in any one
of the 13 genes.
 It is the most severe of the PBD’s.
SYMPTOMS:

6. EXTERNAL SYMPTOMS INTERNAL SYMPTOMS
o Defects in the face, eyes or
development.
o Enlargedliver.
o Upstanding eyes, high
forehead.
o Increased level of copper or
iron in blood.
o Loss of muscle tone/ extreme
weakness.
o Inability tomove, intellectual
disability.
o Seizure activity or jaundice. o Gastrointestinal bleeding.