Involved in the degradation of phospho-AI-2, thereby terminating induction of the lsr operon and closing the AI-2 signaling cycle. Catalyzes the transfer of an acetyl moiety from 3-hydroxy-5-phosphonooxypentane-2,4-dione to CoA to form glycerone phosphate and acetyl-CoA. acetyl-CoA + dihydroxyacetone phosphate = 3-hydroxy-2,4-dioxopentyl phosphate + CoA Homodecamer. Belongs to the DeoC/FbaB aldolase family.