Fructose-1,6-bisphosphate and Fructose-6-phosphate: The conversion of fructose-1,6- bisphosphate to fructose-6-phosphate is catalysed by fluctose-1,6-bisphosphatase which is the major regulatory enzyme in gluconeogenesis. This enzyme is present in liver, kidney and striated muscle but absent from adipose tissue, heart muscle and smooth muscle. Fructose-1,6 bisphosphatase is an allosteric enzyme, activated by citrate and inhibited by AMP and fructose- l,6-bisphosphate.