Aspartate transaminase (AST) is an enzyme found in various tissues, including the liver, heart, and muscles. It plays a crucial role in amino acid metabolism by facilitating the transfer of an amino group from aspartate to α-ketoglutarate, producing oxaloacetate and glutamate. AST is often measured in blood tests to assess liver function and detect potential liver damage or disease. Elevated levels of AST can indicate conditions such as hepatitis, cirrhosis, or myocardial infarction, while normal levels suggest healthy liver and muscle function.