6JDW

CRYSTAL STRUCTURE OF HUMAN L-ARGININE:GLYCINE AMIDINOTRANSFERASE IN COMPLEX WITH GAMMA-AMINO BUTYRIC ACID

6JDW の概要

• エントリーDOI: 10.2210/pdb6jdw/pdb
• 分子名称: PROTEIN (L-ARGININE:GLYCINE AMIDINOTRANSFERASE), GAMMA-AMINO-BUTANOIC ACID (3 entities in total)
• 機能のキーワード: transferase, creatine biosynthesis, catalytic triad, reaction mechanism, novel fold, fivefold pseudosymmetry
• 由来する生物種: Homo sapiens (human)
• 細胞内の位置: Isoform 1: Mitochondrion inner membrane; Peripheral membrane protein; Intermembrane side. Isoform 2: Cytoplasm: P50440
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 44444.61

構造登録者

Fritsche, E.,Humm, A.,Huber, R. (登録日: 1998-10-12, 公開日: 1999-02-09, 最終更新日: 2023-11-15)

主引用文献

Fritsche, E.,Humm, A.,Huber, R.
The ligand-induced structural changes of human L-Arginine:Glycine amidinotransferase. A mutational and crystallographic study.
J.Biol.Chem., 274:3026-3032, 1999

PubMed Abstract: Human L-arginine:glycine amidinotransferase (AT) shows large structural changes of the 300-flap and of helix H9 upon binding of L-arginine and L-ornithine, described as a closed and an open conformation (Humm, A., Fritsche, E., Steinbacher, S., and Huber, R. (1997) EMBO J. 16, 3373-3385). To elucidate the structural basis of these induced-fit movements, the x-ray structures of AT in complex with the amidino acceptor glycine and its analogs gamma-aminobutyric acid and delta-aminovaleric acid, as well as in complex with the amidino donor analogs L-alanine, L-alpha-aminobutyric acid, and L-norvaline, have been solved at 2.6-, 2.5-, 2.37-, 2.3-, 2.5-, and 2.4-A resolutions, respectively. The latter three compounds were found to stabilize the open conformer. The glycine analogs bind in a distinct manner and do not induce the transition to the open state. The complex with glycine revealed a third binding mode, reflecting the rather broad substrate specificity of AT. These findings identified a role for the alpha-amino group of the ligand in stabilizing the open conformer. The kinetic, structural, and thermodynamic properties of the mutants ATDeltaM302 and ATDelta11 (lacks 11 residues of H9) confirmed the key role of Asn300 and suggest that in mammalian amidinotransferases, the role of helix H9 is in accelerating amidino transfer by an induced-fit mechanism. Helix H9 does not add to the stability of the protein.

PubMed: 9915841
DOI: 10.1074/jbc.274.5.3026

実験手法

X-RAY DIFFRACTION (2.5 Å)