The key difference between phagolysosome and phagosome is that phagolysosome is a cytoplasmic body formed by the fusion of a phagosome with a lysosome. Meanwhile, phagosome is a vesicle formed around the particles engulfed by a phagocytic cell during phagocytosis.
Phagocytosis is a defence mechanism used in certain cells or organisms to remove foreign particles from the body. Phagocytes are the cells that carry out phagocytosis. Phagocytes are types of white blood cells, especially, neutrophils, monocytes and macrophages present in the blood. These cells protect the body by detecting foreign particles such as bacteria, toxins, dead and dying somatic cells, etc. Phagocytes then engulf and destroy them. Phagocytosis is a kind of endocytosis. By phagocytosis, solid particles internalize into a structure called a phagosome. Once they are trapped inside the phagosome, they fuse with lysosomes and form phagolysosomes. Then using the lysosome hydrolase enzymes, the particles inside the phagosome are degraded and destroyed.
CONTENTS
1. Overview and Key Difference
2. What is Phagolysosome
3. What is Phagosome
4. Similarities Between Phagolysosome and Phagosome
5. Side by Side Comparison – Phagolysosome vs Phagosome in Tabular Form
6. Summary
What is Phagolysosome?
Phagolysosome is a cytoplasmic vesicle formed by the fusion of a phagosome and a lysosome. In order to destroy engulfed particles, including pathogenic microorganisms, it is necessary to fuse the phagosome with a lysosome that contains hydrolytic enzymes. Lysosome releases its content into the phagosome. The interior environment becomes acidic due to the lysosome content. Then the hydrolytic enzymes digest the engulfed materials within the phagolysosome. After digestion, useful materials are moved to the cytoplasm of the cell while other substances are removed from the cell by exocytosis.
What is Phagosome?
A phagosome is a vesicle formed during phagocytosis. When a phagocyte encounters solid particles near it, it invaginates its plasma membrane and surrounds the solid matter, forming a vesicle.
Figure 01: Phagocytosis
Since the vesicle is a part of the phagocytic cell, it is known as a phagosome. Phagosomes mature undergoing several steps. Once a phagosome buds off inside the cell, it becomes a nascent phagosome. Then it matures into an early phagosome and then into a late phagosome. Next, it fuses with a lysosome to form the phagolysosome.
What are the Similarities Between Phagolysosome and Phagosome?
- Both phagosome and phagolysosome are found within phagocytic cells.
- They are two structures formed during phagocytosis.
- Both are membrane-bound vesicles.
- The engulfed particles are found inside both types of vesicles.
- Both phagolysosome and phagosome are important in engulfing and destroying harmful microorganisms.
- These types of vesicles disappear after the destruction of microorganisms.
What is the Difference Between Phagolysosome and Phagosome?
Phagolysosome is a vesicle formed by the union of a phagosome and a lysosome while phagosome is a vesicle formed by a phagocytic cell engulfing solid materials. So, this is the key difference between phagolysosome and phagosome. Phagolysosome has both engulfed materials and lysosome content, while phagosome only contains materials.
Moreover, phagolysosome is important in order to digest engulfed materials, while the formation of phagosome is important in order to take up solid matter inside the cell. Another difference between phagolysosome and phagosome is that phagolysosome is microbicidal since it contains hydrolytic enzymes while phagosome is not microbicidal.
Below is a summary of the difference between phagolysosome and phagosome in tabular form.
Summary – Phagolysosome vs Phagosome
Phagosome and phagolysosome are two types of vesicles seen during phagocytosis. Phagolysosome is a cytoplasmic vesicle formed by the fusion of a phagosome with a lysosome. A phagosome is a vesicle formed, engulfing the solid materials that have come near the phagocytotic cell. Once the phagosome if formed, it fuses with a lysosome which carries hydrolytic enzymes. Hydrolytic enzymes are essential in order to digest the engulfed materials, including pathogenic microorganisms. Therefore, phagolysosome is microbicidal since it has hydrolytic enzymes, unlike phagosome. So, this ends the summary of the difference between phagolysosome and phagosome.
Reference:
1. “Phagolysosome.” Wikipedia, Wikimedia Foundation, 19 July 2019, Available here.
2. Kinchen, Jason M, and Kodi S Ravichandran. “Phagosome Maturation: Going through the Acid Test.”Nature Reviews. Molecular Cell Biology, U.S. National Library of Medicine, Oct. 2008, Available here.
Image Courtesy:
1. “Phagocytosis2” By GrahamColm at English Wikipedia (CC BY-SA 3.0) via Commons Wikimedia