Structural highlights
Disease
G6PI_HUMAN Defects in GPI are the cause of hemolytic anemia non-spherocytic due to glucose phosphate isomerase deficiency (HA-GPID) [MIM:613470. It is a form of anemia in which there is no abnormal hemoglobin or spherocytosis. It is caused by glucose phosphate isomerase deficiency. Severe GPI deficiency can be associated with hydrops fetalis, immediate neonatal death and neurological impairment.
Function
G6PI_HUMAN Besides it's role as a glycolytic enzyme, mammalian GPI can function as a tumor-secreted cytokine and an angiogenic factor (AMF) that stimulates endothelial cell motility. GPI is also a neurotrophic factor (Neuroleukin) for spinal and sensory neurons.[1] [2] [3]
Publication Abstract from PubMed
Modulation of enzyme activity by metabolites represents the most efficient and rapid way of controlling metabolism. Investigating enzyme-metabolite interactions can deepen our understanding of metabolic control and aid in identifying enzyme modulators with potential therapeutic applications. These interactions vary in strength, with dissociation constants (K(d)) ranging from strong (nm) to weak (mum-mm). However, weak interactions are often overlooked due to the challenges in studying them. Despite this, weak modulators can reveal unknown binding modes and serve as starting points for compound optimization. In this study, we aimed to identify metabolites that weakly modulate the activity of human glucose-6-phosphate isomerase (GPI) and triosephosphate isomerase (TPI), which are potential therapeutic targets in tumor glycolysis. Through a combination of activity and binding assays, the screening revealed multiple weak inhibitors for the two targets, causing partial attenuation of their activity, with K(d) and K(i) in the low mm range. X-ray crystallography revealed six orthosteric ligands binding to the active sites - four inhibitors of GPI and two of TPI. Our findings underscore the role of weak interactions in enzyme regulation and may provide structural insights that could aid the design of inhibitors targeting human GPI and TPI in cancer intervention.
Human glycolysis isomerases are inhibited by weak metabolite modulators.,Jonatansdottir YY, Rolfsson O, Hjorleifsson JG FEBS J. 2025 Feb 27. doi: 10.1111/febs.70049. PMID:40014465[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Haga A, Niinaka Y, Raz A. Phosphohexose isomerase/autocrine motility factor/neuroleukin/maturation factor is a multifunctional phosphoprotein. Biochim Biophys Acta. 2000 Jul 14;1480(1-2):235-44. PMID:11004567
- ↑ Funasaka T, Haga A, Raz A, Nagase H. Tumor autocrine motility factor is an angiogenic factor that stimulates endothelial cell motility. Biochem Biophys Res Commun. 2001 Jul 6;285(1):118-28. PMID:11437381 doi:10.1006/bbrc.2001.5135
- ↑ Amraei M, Nabi IR. Species specificity of the cytokine function of phosphoglucose isomerase. FEBS Lett. 2002 Aug 14;525(1-3):151-5. PMID:12163179
- ↑ Jónatansdóttir YY, Rolfsson Ó, Hjörleifsson JG. Human glycolysis isomerases are inhibited by weak metabolite modulators. FEBS J. 2025 Feb 27. PMID:40014465 doi:10.1111/febs.70049
