Synergistic inhibition of the enzymatic activity of aminopeptidase N by divalent metal ion chelators.

Membranes of HEK293 cells that were transfected with human aminopeptidase N (AP-N, CD13, EC 3.4.11.

Angiotensin AT4 receptor ligand interaction with cystinyl aminopeptidase and aminopeptidase N: [125I]Angiotensin IV only binds to the cystinyl aminopeptidase apo-enzyme.

Due to its high affinity for [(125)I]Angiotensin IV, cystinyl aminopeptidase (CAP) has recently been assigned as the 'angiotensin AT(4) receptor'. Since the aminopeptidase N (AP-N) activity is also susceptible to inhibition by Angiotensin IV, it might represent an additional target for this peptide. Based on [(125)I]Angiotensin IV binding and catalytic activity measurements, we compared the ligand interaction properties of recombinant human CAP and human AP-N.