Catalyzes two subsequent steps in gluconeogenesis: the aldol condensation of dihydroxyacetone phosphate (DHAP) and glyceraldehyde-3-phosphate (GA3P) to fructose-1,6-bisphosphate (FBP), and the dephosphorylation of FBP to fructose-6-phosphate (F6P). beta-D-fructose 1,6-bisphosphate + H2O = beta-D-fructose 6-phosphate + phosphate beta-D-fructose 1,6-bisphosphate = D-glyceraldehyde 3-phosphate + dihydroxyacetone phosphate Can also use Zn(2+) or Mn(2+) in vitro, although with much less efficiency than Mg(2+). kcat is 2.5 sec(-1) for the FBPase activity (at 80 degrees Celsius) (PubMed:15274916). kcat is 0.62 sec(-1) for the FBPase activity (at 48 degrees Celsius). kcat is 0.91 sec(-1) for the FBP aldolase activity in the anabolic direction (at 48 degrees Celsius). kcat is 0.027 sec(-1) for the FBP aldolase activity in the catabolic direction (at 48 degrees Celsius) (PubMed:21983966). Optimum pH is 8.0. Optimum temperature is over 100 degrees Celsius. Carbohydrate biosynthesis; gluconeogenesis. Homooctamer; dimer of tetramers. Consists of a single catalytic domain, but remodels its active-site architecture via a large structural change to exhibit dual activities. Belongs to the FBP aldolase/phosphatase family.