Aminopeptidases

Aminopeptidases catalyze the removal of amino acids from the amino terminus of proteins and peptides. They express different substrate specificities - for example, leucyl aminopeptidase preferentially cleaves leucine residues whilst arginyl aminopeptidase releases arginine and lysine residues. Aminopeptidases are generally classed as metalloproteases, and are often associated with zinc.

Aminopeptidases were some of the earliest proteases characterized. They are classified by various characteristics, including the number of amino acids they cleave from the amino terminus; the relative efficiency with which they remove the amino acids; and cellular location - some are secreted, some are not. Other qualities, such as susceptibility to bestatin inhibition, also help characterize these enzymes.

Due to their integral role in protein maturation and peptide degradation, aminopeptidases are key to cellular protein turnover, which in turn can affect cell growth and survival. Inhibiting these enzymes suggests therapeutic benefits in the treatment of cancer, since the build-up of peptides and reduction in the levels of free amino acids can impede tumor cell survival. Hormone levels are also influenced by aminopeptidase activity - for example, pyroglutamyl aminopeptidase II degrades thyrotropin-releasing hormone, inactivating it. Other roles include regulation of angiogenesis (aminopeptidase N); inflammatory processes (leukotriene A₄ hydrolase, aminopeptidase B); and blood pressure (aminopeptidase A).

External sources of pharmacological information for Aminopeptidases :

• BJP Guide

Aminopeptidase Gene Data