Synthesis and degradation of fructose 2,6-bisphosphate. beta-D-fructose 2,6-bisphosphate + H2O = beta-D-fructose 6-phosphate + phosphate ATP + beta-D-fructose 6-phosphate = ADP + beta-D-fructose 2,6-bisphosphate + H(+) In the C-terminal section; belongs to the phosphoglycerate mutase family.