5nukleotidas

5'-Nucleotidase (commonly abbreviated as 5'-NT or 5nukleotidas in some languages) is an enzyme classified under the hydrolase category, specifically EC 3.1.3.5. It catalyzes the hydrolysis of nucleoside monophosphates into nucleosides and inorganic phosphate. This reaction plays a critical role in nucleotide metabolism, particularly in the regulation of intracellular nucleotide levels and the salvage pathway of purine and pyrimidine bases.

The enzyme is widely distributed across various tissues, including the liver, kidney, intestine, and red blood cells. In humans, 5'-NT exists as a membrane-bound form, often associated with cell membranes, and a soluble form found in the cytoplasm. The membrane-bound variant is particularly abundant in the brush border of intestinal epithelial cells and the apical membrane of renal proximal tubule cells, where it aids in nutrient absorption and ion balance.

Genetic mutations affecting 5'-NT activity have been linked to certain metabolic disorders, though they are relatively rare. The enzyme’s role in maintaining cellular energy balance and nucleotide homeostasis underscores its importance in physiological processes. Additionally, 5'-NT is used as a biomarker in clinical diagnostics, particularly in assessing liver function and certain types of cancer, such as hepatocellular carcinoma, where elevated serum levels may indicate malignancy.

Structurally, 5'-NT belongs to the phosphoesterase family and exhibits a conserved catalytic domain responsible for its hydrolytic activity. Its regulation involves feedback mechanisms, where high concentrations of nucleosides can inhibit its activity, ensuring metabolic balance. Research into 5'-NT continues to explore its potential as a therapeutic target in diseases involving nucleotide dysregulation.