Glycosome
The term was first used by Scott and Still in 1968 after they realized that the glycogen in the cell was not static but rather a dynamic molecule.
The term glycosome is also used for glycogen-containing structures found in hepatocytes responsible for storing sugar, but these are not membrane bound organelles.
Other glycosomes have been found to be attached to myofibrils and mitochondria, rough endoplasmic reticulum, sarcolemma, polyribosomes, or the Golgi apparatus.
The glycosomes in the rough and smooth endoplasmic reticulum make use of its glycogen synthase and phosphorylase phosphatases.
These processes include glycolysis, purine salvage, beta oxidation of fatty acids, and ether lipid synthesis.
[5] The main function that the glycosome serves is of the glycolytic pathway that is done inside its membrane.
In the cell, action in the cytosol, the mitochondria, and the glycosome are all completing the function of energy metabolism.
The parasites which have glycosomes present in their cells cannot make purine de novo.
These enzymes found in the glycosome to help with synthesis are guanine and adenine phosphoribosyl transferase, hypoxanthine, and xanthine pho tran.
Paul Erlich's findings as early as 1883 noted that from the microscope he could tell that glycogen in the cell was always found with what he called a carrier, later known to be protein.
This gives the illusion of glycogen disappearing as it is not stained, but it dissociates from the protein that it is normally associated with in the glycosome.
The initiation of synthesis of glycogen requires glycogenin, found in glycosomes, a protein primer.
These structures relate to the other organelles mentioned such as the myofibrils, mitochondria, and endoplasmic reticulum.
These glycosomes are not found to form groups but rather stay separate as single organelles.
[1] The glycosomes are the most divergent of the different types of organelles stemming from peroxisomes, especially as seen in the trypanosomes.
Peroxisomes of higher eukaryotes are very similar to the glycosomes and the glyoxysomes that are found in some plants and fungi.
The glycosome shares the same basic level structure of a single membrane and a very dense protein matrix.
Some studies have shown that some of the enzymes and pathways that are found in the peroxisome are also seen in glycosomes of some species of the trypanosomes.
It has been speculated that the since it has been found that glycosomes possess plastid like proteins, a lateral gene transfer happened long ago from an organism capable of photosynthesis whose genes were transferred to have the resultant peroxisomes and glycosomes.
