1KM1

Orotidine monophosphate decarboxylase mutant S127A crystal structure

1KM1 の概要

• エントリーDOI: 10.2210/pdb1km1/pdb
• 関連するPDBエントリー: 1KLY 1KLZ 1KM0 1KM2 1KM3 1KM4 1KM5 1KM6
• 分子名称: OROTIDINE 5'-PHOSPHATE DECARBOXYLASE, 6-AZA URIDINE 5'-MONOPHOSPHATE (3 entities in total)
• 機能のキーワード: tim barrel, lyase
• 由来する生物種: Methanothermobacter thermautotrophicus
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 54210.03

構造登録者

Wu, N.,Gillon, W.,Pai, E.F. (登録日: 2001-12-13, 公開日: 2002-06-28, 最終更新日: 2024-02-14)

主引用文献

Wu, N.,Gillon, W.,Pai, E.F.
Mapping the active site-ligand interactions of orotidine 5'-monophosphate decarboxylase by crystallography.
Biochemistry, 41:4002-4011, 2002

PubMed Abstract: The crystal structures of orotidine 5'-monophosphate decarboxylases from four different sources have been published recently. However, the detailed mechanism of catalysis of the most proficient enzyme known to date remains elusive. As the ligand-protein interactions at the orotate binding site are crucial to the understanding of this enzyme, we mutated several of the residues surrounding the aromatic part of the substrate, individually and in combination. The ensuing effects on enzyme structure and stability were characterized by X-ray crystallography of inhibitor, product, or substrate complexes and by chemical denaturation with guanidine hydrochloride, respectively. The results are consistent with the residues K42D70K72D75B being charged and forming an 'alternate charge network' around the reactive part of the substrate. In addition to exerting charge-charge repulsion on the orotate carboxylate, Asp70 also makes a crucial contribution to enzyme stability. Consequently, orotidine 5'-monophosphate decarboxylases seem to require the presence of a negative charge at this position for catalysis as well as for correct and stable folding.

PubMed: 11900543
DOI: 10.1021/bi015758p

実験手法

X-RAY DIFFRACTION (1.6 Å)