Salivary alpha-amylase (HSAmy)

Salivary alpha-amylase is a calcium-dependent enzyme produced in the salivary glands and secreted into the mouth. It initiates the breakdown of starch into simpler sugars (maltose and dextrins) during mastication, facilitating chemical digestion before food reaches the stomach[1][6][8]. Structurally, it comprises a single chain of 496 amino acids organized into three domains (A, B, and C), with a (β/α)8 barrel in domain A housing the catalytic site[2][3][4][5][6]. The enzyme requires calcium and chloride ions for structural stability and catalytic activity[1][2][6]. Beyond digestion, salivary amylase interacts with oral bacteria and enamel, contributing to plaque formation and oral microbial colonization[6]. Variation in its level and gene copy number (AMY1) is implicated in metabolic and dental diseases[6][8]. Its activity is commonly used as a biomarker in metabolic studies, and it can be inhibited by drugs like acarbose, though therapeutic inhibition is generally directed at pancreatic (not salivary) amylase[3].

Other names

Alpha-amylaseSalivary amylaseAMY1 (gene symbol)HSAmy (protein abbreviation)

Drugs like acarbose act as competitive inhibitors by binding to the active site of alpha-amylase, preventing starch breakdown into glucose and reducing postprandial hyperglycemia[3].