<p>Aminobutyraldehyde dehydrogenase functions in the putrescine degradation pathway. It catalyses the oxidation of 4 aminobutyraldehyde to 4 aminobutyrate a neurotransmitter. YdcW encodes gamma-aminobutyraldehyde dehydrogenase (ABALDH) in the wild-type <taxon tax_id="83333">Escherichia coli</taxon> (strain K12). It is a tetramer and when coupled with YgjG putrescine transaminase in vitro, putrescine was converted into gamma-aminobutyric acid [<cite idref="PUB00042939"/>]. The tetramer is composed of identical subunits. The same enzyme from <taxon tax_id="1667">Arthrobacter sp.</taxon> utilises both NAD+ and NADP+ as coenzymes. It functions optimally at pH 8.0 [<cite idref="PUB00043488"/>].</p>