This enzyme is proposed to act in the ring-opening step of phenylacetic acid degradation which follows ligation of the acid with coenzyme A (by PaaF) and hydroxylation by a multicomponent non-heme iron hydroxylase complex (PaaGHIJK). Gene symbols have been standardized in. This enzyme is related to aldehyde dehydrogenases and has domains which are members of the pfam00171 and pfam01575 families. This family includes paaN genes from Pseudomonas, Sinorhizobium, Rhodopseudomonas, Escherichia, Deinococcus and Corynebacterium. Another homology family (TIGR02288) includes several other species.