Anti-PCAP antibodies enable researchers to detect and measure the PCAP antigen in biological samples. This target is a reported synonym of the CSAD gene, which encodes cysteine sulfinic acid decarboxylase. This protein is known to catalyze the decarboxylation of L-aspartate, 3-sulfino-L-alanine (cysteine sulfinic acid), and L-cysteate to beta-alanine, hypotaurine and taurine, respectively. The human version of PCAP has a canonical amino acid length of 493 residues and a protein mass of 55 kilodaltons, although 3 isoforms have been identified. It is reported to be widely expressed in many tissue types. PCAP is a member of the Group II decarboxylase protein family.