. "Catalysis of the reaction: L-erythrulose 1-phosphate = formaldehyde + glycerone phosphate." . . "ketotetrose-phosphate aldolase activity" . "erythrose-1-phosphate synthase activity" . "erythrulose-1-phosphate formaldehyde-lyase (glycerone-phosphate-forming)" . "erythrulose-1-phosphate formaldehyde-lyase activity" . "erythrulose-1-phosphate synthetase activity" . "phosphoketotetrose aldolase activity" . . .