Home Economics American Trypanosomiasis Chagas Disease, Second Edition: One Hundred Years of Research
All trypanosomatids contain spherical structures with a homogeneous matrix that are surrounded by a unit membrane and distributed throughout the cell. They are a special type of peroxisome, designated as the glycosome due to the concentration of glycolytic pathway enzymes in this organelle.14-16 Since catalase is found in the gly- cosomes of monogenetic but not digenetic trypanosomatids, this organelle is now considered to be a special type of peroxisome. In addition to catalase, the peroxisomes of mammalian cells have more than 50 different enzymes involved in metabolic pathways, such as peroxide metabolism, 6-oxidation of fatty acids, and ether phospholipid synthesis. Studies have found that, in addition to the pathways described above, other metabolic pathways that occur in the cytosol of other cells also take place in the glycosomes of trypanosomatids, including carbon dioxide fixa- tion,17 purine salvage and de novo pyrimidine biosynthesis, fatty acid elongation, isoprenoid biosynthesis, and sterol biosynthesis.14 The glycosome does not possess a genome. Therefore, all of the proteins found in it are encoded by nuclear genes, translated on free ribosomes and then posttranslationally imported into the organelle.
The biogenesis of the glycosome seems to be similar to that of peroxisome.18
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