3OT9

Phosphopentomutase from Bacillus cereus bound to glucose-1,6-bisphosphate

3OT9 の概要

• エントリーDOI: 10.2210/pdb3ot9/pdb
• 関連するPDBエントリー: 3M8W 3M8Y 3M8Z
• 分子名称: Phosphopentomutase, MANGANESE (II) ION, GLYCEROL, ... (5 entities in total)
• 機能のキーワード: alkaline phosphatase like core domain, phosphopentomutase, ribose-5-phosphate, ribose-1-phosphate, glucose-1, 6-bisphosphate, phosphoryl transfer, isomerase
• 由来する生物種: Bacillus cereus
• 細胞内の位置: Cytoplasm (By similarity): Q818Z9
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 134883.75

構造登録者

Panosian, T.D.,Nannemann, D.P.,Watkins, G.,Phalen, V.,Wadzinski, B.,Bachmann, B.O.,Iverson, T.M. (登録日: 2010-09-10, 公開日: 2010-12-29, 最終更新日: 2023-09-06)

主引用文献

Panosian, T.D.,Nannemann, D.P.,Watkins, G.R.,Phelan, V.V.,McDonald, W.H.,Wadzinski, B.E.,Bachmann, B.O.,Iverson, T.M.
Bacillus cereus Phosphopentomutase Is an Alkaline Phosphatase Family Member That Exhibits an Altered Entry Point into the Catalytic Cycle.
J.Biol.Chem., 286:8043-8054, 2011

PubMed Abstract: Bacterial phosphopentomutases (PPMs) are alkaline phosphatase superfamily members that interconvert α-D-ribose 5-phosphate (ribose 5-phosphate) and α-D-ribose 1-phosphate (ribose 1-phosphate). We investigated the reaction mechanism of Bacillus cereus PPM using a combination of structural and biochemical studies. Four high resolution crystal structures of B. cereus PPM revealed the active site architecture, identified binding sites for the substrate ribose 5-phosphate and the activator α-D-glucose 1,6-bisphosphate (glucose 1,6-bisphosphate), and demonstrated that glucose 1,6-bisphosphate increased phosphorylation of the active site residue Thr-85. The phosphorylation of Thr-85 was confirmed by Western and mass spectroscopic analyses. Biochemical assays identified Mn(2+)-dependent enzyme turnover and demonstrated that glucose 1,6-bisphosphate treatment increases enzyme activity. These results suggest that protein phosphorylation activates the enzyme, which supports an intermolecular transferase mechanism. We confirmed intermolecular phosphoryl transfer using an isotope relay assay in which PPM reactions containing mixtures of ribose 5-[(18)O(3)]phosphate and [U-(13)C(5)]ribose 5-phosphate were analyzed by mass spectrometry. This intermolecular phosphoryl transfer is seemingly counter to what is anticipated from phosphomutases employing a general alkaline phosphatase reaction mechanism, which are reported to catalyze intramolecular phosphoryl transfer. However, the two mechanisms may be reconciled if substrate encounters the enzyme at a different point in the catalytic cycle.

PubMed: 21193409
DOI: 10.1074/jbc.M110.201350

実験手法

X-RAY DIFFRACTION (1.75 Å)