Anti-PAPT antibodies enable researchers to detect and measure the PAPT antigen in biological samples. This target is a reported synonym of the SRM gene, which encodes spermidine synthase. This protein is known to function in metabolic processes, among other biological roles. The human version of PAPT has a canonical amino acid length of 302 residues and a protein mass of 33.8 kilodaltons. It is reported to be widely expressed in many tissue types. PAPT is a member of the Spermidine/spermine synthase protein family.