Glycoproteinoses

Introduction to Glycoprotoidoses

Glycoproteins are proteins consisting of carbohydrate residues and amino acids. Glycolipids are lipids containing glycolipids. The importance of these compounds lies in their participation in many vital biochemical processes. Some disorders are associated with the accumulation of glycolipids in plasma or tissues, which can lead to serious health consequences. In this article we will look at various glycoproteinoses and the mechanisms of their pathogenesis.

Glycosidases Description * **Xanthine oxidase** is an enzyme that catalyzes the oxidation of one of the three mitochondrial coenzymes to uric acid. A mutation in the gene encoding xanthine oxidase is associated with an inherited urokinase defect in humans. _X-linked recessive_

* **conjugated leucine aminopeptidase - is involved in the metabolism of oligopeptides and can lead to the development of Gaia-Phips disease.

Phenylketonuria This is a hereditary disorder associated with impaired metabolism of amino acids in the body. It occurs due to a hereditary defect in the gene responsible for the metabolism of phenylalanine, which is necessary for the synthesis of many proteins. A characteristic feature of this disorder is the absence of phenol-containing compounds in tissues and blood. This leads to mental retardation and other mental development disorders in children. Treatment consists of prescribing a low-phenyl diet. Drugs have now been developed that can block the breakdown pathway of phenylalane, which prevents further damage and improves the condition of patients. * Diagnosis is based on clinical and biochemical parameters. Urinalysis reveals an increased concentration of phenylacetic acid, as well as the presence of fetol in it in the absence of symptoms. To confirm the diagnosis, genetic tests are prescribed. The diagnosis of the disease has improved significantly thanks to the introduction of neonatal screening for phenylketonuria into widespread clinical practice. Screening is done by testing for phenylacetate in the umbilical cord, eliminating the need to test blood in an affected child until symptoms appear. The test is very sensitive and specific; when the level of phenylacet increases to a level above a certain threshold value, information is given about the need for additional research. Identification of a newborn suffering from phenylketonism based on the results of this screening allows him to be treated as early as possible, which eliminates the risk of developing various complications associated with the disease. Isolated deficiency of substrate specificity of the enzyme glutaminase associated with broader genetic composition The sign is observed only in the liver, no symptoms are detected, genetic testing is carried out. Genetic diagnosis involves the study of 2 polymorphisms in the _GLT ​​gene) responsible for the development and progression of disorders. There are specific (characteristic of a certain type) and nonspecific signs that can be useful for providing differential diagnosis. It must be remembered that in cases of icuarin and fecocia