Molecular Classification
Enzyme
Other Names
Transaminase, ALT, AST, Alanine aminotransferase, Aspartate aminotransferase
Disease Roles
Liver diseaseHepatitisFatty liver disease

Aminotransferase Overview

Aminotransferases, also known as transaminases, are enzymes that catalyze the transfer of an amino group from an amino acid to an α-keto acid. This process is central to amino acid metabolism and gluconeogenesis. The two most clinically significant aminotransferases are alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Elevated serum levels of ALT or AST typically indicate cell membrane damage leading to enzyme leakage into blood—most commonly from hepatocytes but also from other affected tissues depending on which enzyme is elevated more prominently. Measurement of these enzymes forms part of standard clinical panels assessing hepatic function.

Mechanism of Action

Inhibition of enzyme activity (though this is less common as a direct therapeutic strategy; more often, changes in activity are used as biomarkers)

Biological Functions

Amino acid metabolism
Gluconeogenesis
Nitrogen transfer
Protein metabolism

Disease Associations

Liver disease
Hepatitis
Fatty liver disease
Drug toxicity
Heart damage
Muscle damage
Kidney damage
Pancreas damage
Red blood cell damage

Safety Considerations

  • Elevated levels can indicate liver or tissue damage
  • False positives or negatives due to other factors (e.g., muscle injury)

Interacting Drugs

Hepatotoxic drugs (e.g., acetaminophen, some antibiotics, statins)

Associated Biomarkers

Biomarker
ALT levels
AST levels