Updated project metadata. To identify the acetylation site(s) on hemocyanin (PvHMC) that modulate its functions, purified PvHMC from the plasma of HDACs inhibitor (NAM and TSA) treated shrimp was analyzed by tandem mass spectrometry. Four lysine acetylation sites (K179, K188, K648, and K653) were found on the small molecular weight subunit hemocyanin (PvHMCS) and six sites (K117, K188, K197, K239, K481, and K484) on the large subunit (PvHMCL).