Recombinant Human Aminopeptidase A/ENPEP Protein, CF

The human ENPEP gene encodes aminopeptidase A (APA), which is also known as glutamyl aminopeptidase (EAP), aspartate aminopeptidase, angiotensinase A, Ca²⁺-activated glutamate aminopeptidase, membrane aminopeptidase II and the BP-1/6C3 antigen (1). The various names reflect its substrate specificity (with a preference for Glu, Asp and angiotensin II as one of the physiological substrates), Ca²⁺-dependence, cellular location (type II membrane protein) and immunological reactivity to the antibody BP-1/6C3. The deduced amino acid sequence of human ENPEP consists of a short cytoplasmic tail (residues 1 to 17), a transmembrane region (residues 18 to 40), and a long ectodomain (residues 41 to 957) (2, 3). In addition to the N-terminal zinc metalloprotease domain, the ectodomain also contains the C-terminal region, which functions as an intramolecular chaperone required for the correct folding, cell surface expression and activity (4). The purified recombinant human ENPEP consists of the entire ectodomain and is active in the assay as described in Activity Assay Protocol.