GLUTAMYL AMINOPEPTIDASE (AMINOPEPTIDASE-A), THE BP-1 6C3 ANTIGEN/

Glutamyl aminopeptidase (aminopeptidase A, EC 3.4.11.7) was first desc ribed in 1961 as a calcium-stimulated aminopeptidase with specificity for N-terminal acidic amino acids. The enzyme was subsequently purifie d and characterized as a membrane-bound ectoenzyme particularly abunda nt in the brush border fractions of kidney and intestine. Early intere st in this enzyme was stimulated by its conversion of angiotensin II t o des-aspartyl angiotensin II (angiotensin III). More recently, glutam yl aminopeptidase has been identified as a pre-B cell differentiation antigen BP-1/6C3. This review focuses on the biochemical properties of this enzyme and its role in the immune and non-immune systems.