6NU1

Crystal Structure of Human PKM2 in Complex with L-cysteine

6NU1 の概要

• エントリーDOI: 10.2210/pdb6nu1/pdb
• 分子名称: Pyruvate kinase PKM, CYSTEINE, 1,6-di-O-phosphono-beta-D-fructofuranose, ... (7 entities in total)
• 機能のキーワード: pyruvate kinase m2, cysteine, inhibition, glycolysis, transferase
• 由来する生物種: Homo sapiens (Human)
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 243125.59

構造登録者

Srivastava, D.,Nandi, S.,Dey, M. (登録日: 2019-01-30, 公開日: 2019-08-21, 最終更新日: 2023-10-11)

主引用文献

Srivastava, D.,Nandi, S.,Dey, M.
Mechanistic and Structural Insights into Cysteine-Mediated Inhibition of Pyruvate Kinase Muscle Isoform 2.
Biochemistry, 58:3669-3682, 2019

PubMed Abstract: Cancer cells regulate key enzymes in the glycolytic pathway to control the glycolytic flux, which is necessary for their growth and proliferation. One of the enzymes is pyruvate kinase muscle isoform 2 (PKM2), which is allosterically regulated by various small molecules. Using detailed biochemical and kinetic studies, we demonstrate that cysteine inhibits wild-type (wt) PKM2 by shifting from an active tetramer to a mixture of a tetramer and a less active dimer/monomer equilibrium and that the inhibition is dependent on cysteine concentration. The cysteine-mediated PKM2 inhibition is reversed by fructose 1,6-bisphosphate, an allosteric activator of PKM2. Furthermore, kinetic studies using two dimeric PKM2 variants, S437Y PKM2 and G415R PKM2, show that the reversal is caused by the tetramerization of wtPKM2. The crystal structure of the wtPKM2-Cys complex was determined at 2.25 Å, which showed that cysteine is held to the amino acid binding site via its main chain groups, similar to that observed for phenylalanine, alanine, serine, and tryptophan. Notably, ligand binding studies using fluorescence and isothermal titration calorimetry show that the presence of phosphoenolpyruvate alters the binding affinities of amino acids for wtPKM2 and vice versa, thereby unravelling the existence of a functionally bidirectional coupling between the amino acid binding site and the active site of wtPKM2.

PubMed: 31386812
DOI: 10.1021/acs.biochem.9b00349

実験手法

X-RAY DIFFRACTION (2.25 Å)