Catalyzes an oxidative deamination of predominantly hydrophobic and aromatic L-amino acids, thus producing hydrogen peroxide that may contribute to the diverse toxic effects of this enzyme (PubMed:29900074, PubMed:31129208). Shows activity on L-Leu, L-Trp, and L-Tyr (PubMed:29900074, PubMed:31129208). Is not active on L-His, L-Ser, L-Arg, L-Ala, L-Glu, L-Cys,L-Lys, L-Val, L-Ile, and L-Thr (PubMed:29900074). Induces apoptosis in Jurkat cells through a hydrogen peroxide-mediated signaling pathway dependent mostly on CASPASE-3 pathway (PubMed:31129208). Remarkably, does no induce toxic effect on peripheral blood lymphocytes (PubMed:31129208). Also exhibits diverse biological activities, such as hemorrhage, hemolysis, edema, and antiparasitic activities, as well as regulation of platelet aggregation (By similarity). Its effect on platelets is controversial, since it either induces aggregation or inhibits agonist-induced aggregation. These different effects are probably due to different experimental conditions (By similarity). Shows antibacterial activity against S.aureus, but not against E.coli (PubMed:29900074). an L-alpha-amino acid + H2O + O2 = a 2-oxocarboxylate + H2O2 + NH4(+) H2O + L-leucine + O2 = 4-methyl-2-oxopentanoate + H2O2 + NH4(+) H2O + L-tryptophan + O2 = H2O2 + indole-3-pyruvate + NH4(+) H2O + L-tyrosine + O2 = 3-(4-hydroxyphenyl)pyruvate + H2O2 + NH4(+) Optimum pH is 8.0. Monomer. This is in contrast with most of its orthologs, that are non-covalently linked homodimers. Expressed by the venom gland. Belongs to the flavin monoamine oxidase family. FIG1 subfamily.