A cryoprotectant induces conformational change in glyceraldehyde-3-phosphate dehydrogenase

作者：Kim Yong Ju

来源：Acta Crystallographica Section F-Structural Biology Communications, 2018, 74(5): 277-282.

DOI：10.1107/S2053230X18004557

<jats:p>Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a glycolytic enzyme, catalyses the conversion of D-glyceraldehyde 3-phosphate to 1,3-bisphosphoglycerate. While mammalian and yeast GAPDHs are multifunctional proteins that have additional functions beyond those involved in glycolysis, including reactions related to nuclear RNA transport, DNA replication/repair, membrane fusion and cellular apoptosis, <jats:italic>Escherichia coli</jats:italic> GAPDH (<jats:italic>ec</jats:italic>GAPDH) has only been reported to function in glycolysis. The S-loop of GAPDH is required for interaction with its cofactor and with other proteins. In this study, the three-dimensional crystal structure of GAPDH treated with trehalose is reported at 2.0 Å resolution. Trehalose was used as a cryoprotectant for the GAPDH crystals. The structure of trehalose-bound <jats:italic>ec</jats:italic>GAPDH was compared with the structures of both NAD<jats:sup>+</jats:sup>-free and NAD<jats:sup>+</jats:sup>-bound <jats:italic>ec</jats:italic>GAPDH. At the S-loop, the bound trehalose in the GAPDH structure induces a 2.4° rotation compared with the NAD<jats:sup>+</jats:sup>-free <jats:italic>ec</jats:italic>GAPDH structure and a 3.1° rotation compared with the NAD<jats:sup>+</jats:sup>-bound <jats:italic>ec</jats:italic>GAPDH structure.</jats:p>

• 出版日期2018-5