Aminopeptidase that preferentially cleaves di- and tripeptides. Also has low epoxide hydrolase activity (in vitro). Can hydrolyze the epoxide leukotriene LTA(4) but it forms preferentially 5,6-dihydroxy-7,9,11,14-eicosatetraenoic acid rather than the cytokine leukotriene B(4) as the product compared to the homologous mammalian enzyme (in vitro). an epoxide + H2O = an ethanediol Binds 1 zinc ion per subunit. Belongs to the peptidase M1 family.