The key difference between glyoxysomes and peroxisomes is that glyoxysomes are present only in plant cells and filamentous fungi while peroxisomes are present in almost all eukaryotic cells. Glyoxysomes are abundant in plant cells of germinating seeds while peroxisomes are abundant in liver and kidney cells.
These two organelles are micro-bodies present in eukaryotic cells. Glyoxysomes are specialized peroxisomes found only in plant cells and filamentous fungi. Peroxisomes are organelles that help to break down long fatty acid chains and detoxify the cell. They degrade alcohols and other harmful compounds.
CONTENTS
1. Overview and Key Difference
2. What are Glyoxysomes
3. What are Peroxisomes
4. Similarities Between Glyoxysomes and Peroxisomes
5. Side by Side Comparison – Glyoxysomes vs Peroxisomes in Tabular Form
6. Summary
What are Glyoxysomes?
Glyoxysomes are a specialized form of peroxysomes present in plant cells, notably in the cells of germinating seeds. They are also present in filamentous fungi. Harry Beevers discovered this organelle in 1961.
Figure 01: Glyoxysome
The prime function of glyoxysome is the catalysis of the formation of acetyl CoA from fatty acids stored within germinating seeds. Hence, some key enzymes of glyoxylate cycle are present in this organelle. They are isocitrate lyase and malate synthase. Furthermore, they contain some enzymes of gluconeogenesis pathway as well. This organelle also helps in photorespiration and nitrogen metabolism in root nodules.
What are Peroxisomes?
Peroxysomes are sub-cellular organelles present in most eukaryotic organisms including fungi, protozoa, plants, and animals. Christian de Duve identified this organelle in 1967. They help in the breakdown of toxic compounds (Ex: H2O2) of the cells that can cause damages. In addition, they degrade alcohols and fatty acids as well. For this purpose, this organelle contains enzymes such as oxidases, peroxidase, catalase, etc.
Figure 01: Glyoxysome
Moreover, peroxisomes also have a role in the formation of phospholipids that are essential for the development of myelin sheaths around the axons.
What are the Similarities Between Glyoxysomes and Peroxisomes?
- Glyoxysomes and peroxisomes are subcellular organelles.
- They are capable of respiration.
- Both organelles contain enzymes of glyoxylate pathway.
- They are present in major groups of eukaryotic organisms.
- They are spherical or oval in shape.
- Both these organelles are microbodies.
What is the Difference Between Glyoxysomes and Peroxisomes?
Glyoxysomes vs Peroxisomes |
|
| Glyoxysomes are specialized peroxysomes that are present in plants and filamentous fungi. | Peroxisomes are single membrane bound organelles found in most of the eukaryotic cells. |
| Prime Function | |
| Catalysis of the formation of acetyl CoA from fatty acids stored within germinating seeds | Breakdown of very long chain fatty acids through beta-oxidation |
| Presence | |
| Present in plant cells and in filamentous fungi | Present in most eukaryotic cells including fungi, plants, animals, protozoa, etc. |
| Detoxification | |
| Do not detoxify alcohols and toxic compounds | Detoxification is done by peroxisomes |
| Presence in Liver and Kidney Cells | |
| Not present in liver and kidney cells | Abundant in liver and kidney cells |
| Presence in Germinating Seeds | |
| Notably found in germinating seeds | Not present in germinating seeds |
| Conversion of Stored Fats into Carbohydrates | |
| Able to convert stored fats into carbohydrates | Unable to convert fats into carbohydrates |
Summary – Glyoxysomes vs Peroxisomes
Glyoxysomes and peroxisomes are two types of organelles or vesicles. Glyoxysomes are notably observed in plant cells of germinating seeds. They are able to convert fats into sugars. Peroxisomes are another type of microbodies that break down long fatty chains. Furthermore, they help in detoxifying harmful compounds. This is the difference between glyoxysomes and peroxisomes.
Reference:
1. “Glyoxysome.” Egyptian Journal of Medical Human Genetics, Elsevier, Available here.
2. “Peroxisome.” Wikipedia, Wikimedia Foundation, 26 Apr. 2018, Available here.
Image Courtesy:
1. “Glyoxysome” By Gevictor – Own work (CC BY-SA 3.0) via Commons Wikimedia
2. “Peroxisome” By Agateller (CC BY-SA 3.0) via Commons Wikimedia