1G4C

CRYSTAL STRUCTURE OF A COMPLEX OF HPPK(R92A) FROM E.COLI WITH MG2+ AT 1.65 ANGSTROM RESOLUTION

1G4C の概要

• エントリーDOI: 10.2210/pdb1g4c/pdb
• 関連するPDBエントリー: 1CBK 1DY3 1EQ0 1EQM 1EQO 1EX8 1F9H 1HKA
• 分子名称: 6-HYDROXYMETHYL-7,8-DIHYDROPTERIN PYROPHOSPHOKINASE, MAGNESIUM ION, CHLORIDE ION, ... (4 entities in total)
• 機能のキーワード: pyrophosphokinase, pyrophosphoryl transfer, folate, hppk, pterin, 6-hydroxymethyl-7, 8-dihydropterin, antimicrobial agent, drug design, transferase
• 由来する生物種: Escherichia coli
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 35940.11

構造登録者

Blaszczyk, J.,Ji, X. (登録日: 2000-10-26, 公開日: 2003-04-15, 最終更新日: 2023-08-30)

主引用文献

BLASZCZYK, J.,Li, Y.,SHI, G.,YAN, H.,JI, X.
Dynamic Roles of Arginine Residues 82 and 92 of Escherichia coli 6-Hydroxymethyl-7,8-dihydropterin Pyrophosphokinase: Crystallographic Studies
Biochemistry, 42:1573-1580, 2003

PubMed Abstract: 6-Hydroxymethyl-7,8-dihydropterin pyrophosphokinase (HPPK) catalyzes the pyrophosphoryl transfer from ATP to 6-hydroxymethyl-7,8-dihydropterin (HP), the first reaction in the folate biosynthetic pathway. Arginine residues 82 and 92, strictly conserved in 35 HPPK sequences, play dynamic roles in the catalytic cycle of the enzyme. At 0.89-A resolution, two distinct conformations are observed for each of the two residues in the crystal structure of the wild-type HPPK in complex with two HP variants, two Mg(2+) ions, and an ATP analogue. Structural information suggests that R92 first binds to the alpha-phosphate group of ATP and then shifts to interact with the beta-phosphate as R82, which initially does not bind to ATP, moves in and binds to alpha-phosphate when the pyrophosphoryl transfer is about to occur. The dynamic roles of R82 and R92 are further elucidated by five more crystal structures of two mutant proteins, R82A and R92A, with and without bound ligands. Two oxidized forms of HP are observed with an occupancy ratio of 0.50:0.50 in the 0.89-A structure. The oxidation of HP has significant impact on its binding to the protein as well as the conformation of nearby residue W89.

PubMed: 12578370
DOI: 10.1021/bi0267994

実験手法

X-RAY DIFFRACTION (1.65 Å)