Bifunctional enzyme that catalyzes the decarboxylation of L-phenylalanine to produce 2-phenylethylamine, which is then oxidized to form 2-phenylacetaldehyde, a constituent of floral scent in petals (PubMed:16766535, PubMed:17928708). 2-phenylacetaldehyde is a precursor of 2-phenylethanol, another constituent of floral scent in petals (PubMed:16766535, PubMed:17928708). H(+) + H2O + L-phenylalanine + O2 = 2-phenylacetaldehyde + CO2 + H2O2 + NH4(+) Homotetramer. Belongs to the group II decarboxylase family.