Catalyzes dephosphorylation of dihydroxyacetone phosphate (DHAP) to produce 1,3-dihydroxyacetone (DHA). Is the main enzyme responsible for DHA production from catabolism of sugars (glucose, fructose, and sucrose) in C.glutamicum. Displays no activity toward nucleoside monophosphates (AMP, CMP, GMP, or UMP). dihydroxyacetone phosphate + H2O = dihydroxyacetone + phosphate Does not show typical Michaelis-Menten type saturation kinetics even when DHAP concentration is increased to 38 mM, suggesting that substrate affinity of HdpA to DHAP is relatively low. This characteristic of HdpA seems to be consistent with the hypothesis of the overflow metabolism, according to which DHA is formed by the action of HdpA only when excess DHAP accumulates in cells. Optimum pH is 5.5-8.0. Homohexamer. Inactivation of hdpA leads to a drastic decrease in DHA production from each of glucose, fructose, and sucrose. No dihydroxyacetone phosphatase activity is detected in the deletion mutant strain. Belongs to the HAD-like hydrolase superfamily.