palmitoylproteiinithioesteraasit
Palmitoylproteiinithioesteraasit are a class of enzymes that catalyze the reversible attachment of palmitic acid to cysteine residues of proteins through a thioester linkage. This post‑translational modification, known as S‑palmitoylation, is essential for regulating protein trafficking, membrane association, stability, and signaling pathways. The enzymes responsible for adding palmitate are typically lysophosphatidic acid acyltransferases (LPATs) or DHHC‑domain palmitoyl‑protein acyltransferases, whereas the enzymes that remove the modification are called acyl‑protein thioesterases. In humans, prominent palmitoyl‑protein thioesterases include palmitoyl‑protein thioesterase 1 (PPT1) and 2 (PPT2). These thioesterases are lysosomal hydrolases that hydrolyze the thioester bond, thereby depalmitoylating substrates and facilitating turnover or recycling of modified proteins.
The catalytic mechanism of PPT1 and PPT2 involves a conserved serine–histidine-aspartate catalytic triad. Substrates enter a
Research continues to elucidate the breadth of palmitoyl‑protein substrates, the regulatory networks that dictate site specificity,