Arphamenine B Hemisulfate is a Zn2+-dependent exopeptidase that selectively removes arginine and/or lysine from the amino terminus of peptide substrates. This enzyme is a metalloprotease commonly found on the surface of mammalian cells, including macrophages and lymphocytes. Arphamenine B Hemisulfate is an aminopeptidase B inhibitor first isolated from bacteria. Like the aminopeptidase inhibitors bestatin and amastatin , arphamenine B enhances immune responses. Arphamenine B Hemisulfate is commonly used to characterize novel proteases.[Cayman Chemical]
arphamenine b is a specific inhibitor of aminopeptidase b first isolated from bacteria [1]. aminopeptidase b (ap-b) is a zn2+-dependent exopeptidase which selectively removes arg and/or lys residues from the n terminus of several peptide substrates. aminopeptidase b has been involved in processing events occurring either during its intracellular transport along the secretory pathway or at the plasma membrane level [2].
arphamenine b inhibited the activity of aminopeptidase enzyme with an ic50 value of 9.0 μm [2]. arphamenine b strongly inhibited transport by the oligopeptide/h+ symporter with the ec50 values of 15 to 67 μm. arphamenine at concentration 100 μm acted as either ineffective or weak inhibitor of membrane-associated hydrolysis [4]. arphamenine selectively suppressed dipeptide hydrolysis [4].
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