Partial catalytic Cys oxidation of human GAPDH to Cys-sulfonic acid.Lia, A., Dowle, A., Taylor, C., Santino, A., Roversi, P.
(2020) Wellcome Open Res 5: 114-114
- PubMed: 32802964
- DOI: 10.12688/wellcomeopenres.15893.2
- Primary Citation of Related Structures:
6YND, 6YNE, 6YNF, 6YNH
- PubMed Abstract:
Background : n-Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) catalyses the NAD + -dependent oxidative phosphorylation of n-glyceraldehyde-3-phosphate to 1,3-diphospho-n-glycerate and its reverse reaction in glycolysis and gluconeogenesis ...
Background : n-Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) catalyses the NAD + -dependent oxidative phosphorylation of n-glyceraldehyde-3-phosphate to 1,3-diphospho-n-glycerate and its reverse reaction in glycolysis and gluconeogenesis. Methods : Four distinct crystal structures of human n-Glyceraldehyde-3-phosphate dehydrogenase ( Hs GAPDH) have been determined from protein purified from the supernatant of HEK293F human epithelial kidney cells. Results : X-ray crystallography and mass-spectrometry indicate that the catalytic cysteine of the protein ( Hs GAPDH Cys152) is partially oxidised to cysteine S-sulfonic acid. The average occupancy for the Cys152-S-sulfonic acid modification over the 20 crystallographically independent copies of Hs GAPDH across three of the crystal forms obtained is 0.31±0.17. Conclusions : The modification induces no significant structural changes on the tetrameric enzyme, and only makes aspecific contacts to surface residues in the active site, in keeping with the hypothesis that the oxidising conditions of the secreted mammalian cell expression system result in Hs GAPDH catalytic cysteine S-sulfonic acid modification and irreversible inactivation of the enzyme.
Leicester Institute of Chemical and Structural Biology and Department of Molecular and Cell Biology, University of Leicester, Henry Wellcome Building, Lancaster Road, LE1 7HB, UK.