Catalyzes the hydrolysis of fructose 1,6-bisphosphate to fructose 6-phosphate. Also displays a low activity toward glucose 1,6-bisphosphate, and no activity against ribulose 1,5-bisphosphate, fructose 2,6-bisphosphate, or fructose 1-phosphate. beta-D-fructose 1,6-bisphosphate + H2O = beta-D-fructose 6-phosphate + phosphate Manganese. Mg(2+), Co(2+), Ni(2+), Ca(2+), Cu(2+) and Zn(2+) cannot support activity. Competitively inhibited by low concentrations of phosphate (IC50 of 1.2 mM) and is also sensitive to Li(+) (IC50 of 15.8 mM). Also inhibited by 1 mM ATP or 50 mM KCl (60% and 20% residual activity, respectively). Slightly activated (40-50%) by the addition of 1 mM dithiothreitol in vitro. The catalytic efficiency of YggF is 3-fold lower than that of GlpX, the other FBPase class 2 in E.coli. Optimum pH is 7.5-8. Homodimer. E.coli K12 also possesses a FBPase class 1 (Fbp), which is the primary FBPase in E.coli and probably represents the main gluconeogenic FBPase. Belongs to the FBPase class 2 family.