1.2.1.3 aldehyde dehydrogenase (NAD+) putrescine degradation III - - PWY-0 1.4.3.4 monoamine oxidase putrescine degradation III - - PWY-0 2.3.1.57 diamine N-acetyltransferase putrescine degradation III - - PWY-0 3.5.1.63 4-acetamidobutyrate deacetylase putrescine degradation III - - PWY-0