Fructose-1,6-Bisphosphatase Deficiency and Metabolic Regulation

Fructose-1,6-bisphosphatase deficiency is a rare autosomal recessive disorder arising from mutations in the FBP1 gene that impair the final dephosphorylation step in gluconeogenesis. Patients typically present in infancy or early childhood with unpredictable episodes of hypoglycaemia, lactic acidosis and metabolic ketoacidosis, precipitated by fasting or febrile illness. At the cellular level, loss of FBPase activity disrupts hepatic glucose output, leading to accumulation of glycolytic intermediates and promoting anaerobic metabolism. Beyond monogenic deficiency, regulation of fructose-1,6-bisphosphatase plays a central role in metabolic homeostasis. Its activity is tightly modulated by allosteric effectors—AMP and fructose 2,6-bisphosphate—ensuring rapid adaptation between gluconeogenesis and glycolysis in response to nutrient status. Recent work has expanded our understanding of genotype–phenotype correlations, refined dietary and pharmacological management strategies, and uncovered novel small-molecule modulators that target the enzyme’s regulatory sites, with implications for rare-disease therapy and metabolic disorders such as type 2 diabetes.

Research from Nature Portfolio

Recent studies have elucidated the molecular and biochemical consequences of FBP1 mutations by classifying missense variants into functional categories based on enzyme stability, active-site perturbation and protein folding. Investigators identified compound heterozygous mutants yielding dramatic loss of catalytic activity and mapped mutations that either disrupt key catalytic motifs or promote misfolding. This stratification of variant types has revealed that certain misfolding mutations may be amenable to rescue by chemical chaperones, opening avenues for targeted therapies. In parallel, advances in high-throughput structural modelling have provided insights into the modulation of FBPase conformation by small molecules, informing rational design of stabilising compounds for inborn errors of gluconeogenesis.

Fructose-1,6-Bisphosphatase Deficiency and Metabolic Regulation publication trend

The graph below shows the total number of articles in fructose-1,6-bisphosphatase deficiency and metabolic regulation across all publications each year (not limited to Nature Index journals).

Technical terms

Fructose-1,6-bisphosphatase (FBPase): A liver enzyme catalysing the hydrolysis of fructose-1,6-bisphosphate to fructose-6-phosphate in gluconeogenesis.

Gluconeogenesis: The metabolic pathway generating glucose from non-carbohydrate precursors, vital during fasting.

Allosteric regulation: Modulation of enzyme activity through effector molecules binding at sites distinct from the active centre.

Missense mutation: A genetic alteration resulting in a single amino-acid substitution within a protein.

Chemical chaperone: A small molecule that stabilises protein folding, potentially restoring function to misfolded enzymes.

References

1. Identification of genotype–biochemical phenotype correlations associated with fructose 1,6-bisphosphatase deficiency. Communications Biology (2023).
2. Clinical and Molecular Characterization of Patients with Fructose 1,6-Bisphosphatase Deficiency. International Journal of Molecular Sciences (2017).
3. The allosteric site of human liver fructose-1,6-bisphosphatase. Analysis of six AMP site mutants based on the crystal structure.. Journal of Biological Chemistry (1994).
4. International practices in the dietary management of fructose 1-6 biphosphatase deficiency. Orphanet Journal of Rare Diseases (2018).
5. Exploration of N-Arylsulfonyl-indole-2-carboxamide Derivatives as Novel Fructose-1,6-bisphosphatase Inhibitors by Molecular Simulation. International Journal of Molecular Sciences (2022).
6. Structures of Mammalian and Bacterial Fructose-1,6-bisphosphatase Reveal the Basis for Synergism in AMP/Fructose 2,6-Bisphosphate Inhibition*. Journal of Biological Chemistry (2007).