Uses
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]
Biological Activity
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].
in vitro
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].
References
[1] umezawa h, aoyagi t, ohuchi s, et al. arphamenines a and b, new inhibitors of aminopeptidase b, produced by bacteria[j]. the journal of antibiotics, 1983, 36(11): 1572-1575.
[2] balogh a, cadel s, foulon t, et al. aminopeptidase b: a processing enzyme secreted and associated with the plasma membrane of rat pheochromocytoma (pc12) cells[j]. journal of cell science, 1998, 111(2): 161-169.
[3] sajid m, isaac r e, harrow i d. purification and properties of a membrane aminopeptidase from ascaris suum muscle that degrades neuropeptides af1 and af2[j]. molecular and biochemical parasitology, 1997, 89(2): 225-234.
[4] daniel h, adibi s a. functional separation of dipeptide transport and hydrolysis in kidney brush border membrane vesicles[j]. the faseb journal, 1994, 8(10): 753-759.
