Phosphatase which shows a preference for 4'-phosphopantetheine and its oxidatively damaged forms (sulfonate or S-sulfonate), providing strong indirect evidence that the phosphatase activity pre-empts damage in the coenzyme A (CoA) pathway (PubMed:27322068). Hydrolyzing excess 4'-phosphopantetheine could constitute a directed overflow mechanism to prevent its oxidation to the S-sulfonate, sulfonate, or other forms (PubMed:27322068). Hydrolyzing 4'-phosphopantetheine sulfonate or S-sulfonate would forestall their conversion to inactive forms of CoA and acyl carrier protein (PubMed:27322068). May play a role in the physiological regulation of CoA intracellular levels (Probable). (R)-4'-phosphopantetheine + H2O = (R)-pantetheine + phosphate (R)-4'-phosphopantetheine sulfonate + H2O = (R)-pantetheine sulfonate + phosphate (R)-4'-phospho-S-sulfopantetheine + H2O = (R)-S-sulfopantetheine + phosphate Phosphatase activity is strongly promoted by several divalent cation ions but is it suggested that Mn(2+) and possibly Ni(2+) represent biologically relevant metal ion cofactors for damage-control phosphatases. Activity is strongly promoted by Co(2+), Ni(2+), Mg(2+) and Mn(2+) (PubMed:27322068). Activity is inhibited by EDTA (PubMed:27322068). kcat is 0.17 sec(-1) with p-nitrophenylphosphate as substrate. kcat is 0.71 sec(-1) with D-pantetheine 4'-phosphate as substrate. kcat is 0.09 sec(-1) with D-pantetheine 4'-phosphate-sulfonate as substrate. Homodimer. Interacts with PKM. Widely expressed with high expression in the muscle (PubMed:11479594). Expressed in the retina and lens epithelium, mainly in ganglion cell layer, outer plexiform layer and retinal pigment layer (at protein level) (PubMed:30585370). Subfamily II proteins have an EGMGR motif about 50 residues from the C-terminus (Probable). This motif lies near the metal-binding residues in the putative substrate-binding cleft 2 (Probable). Subfamily II proteins occur only in eukaryotes, in two forms: as a stand-alone unit in plants, and as a C-terminal domain of pantothenate kinases in plants, animals, and chytrid fungi (Probable). The disease may be caused by variants affecting the gene represented in this entry. In the N-terminal section; belongs to the type II pantothenate kinase family. In the C-terminal section; belongs to the damage-control phosphatase family. Phosphopantetheine phosphatase II subfamily. Despite belonging to the type II pantothenate kinase family, the pantothenate kinase domain contains a Val residue at position 147 and a Trp residue at position 211 instead of the two conserved active site residues, Glu and Arg. Lacks pantothenate kinase activity.