1GUN

MopII from Clostridium pasteurianum complexed with molybdate (partial)

1GUN の概要

• エントリーDOI: 10.2210/pdb1gun/pdb
• 関連するPDBエントリー: 1GUG 1GUO 1GUS 1GUT
• 分子名称: MOLYBDATE BINDING PROTEIN II, MOLYBDATE ION, CALCIUM ION, ... (4 entities in total)
• 機能のキーワード: transport protein, molbindin, molybdate binding, mop
• 由来する生物種: CLOSTRIDIUM PASTEURIANUM
• タンパク質・核酸の鎖数: 6
• 化学式量合計: 43463.16

構造登録者

Schuettelkopf, A.W.,Harrison, J.A.,Hunter, W.N. (登録日: 2002-01-28, 公開日: 2002-02-08, 最終更新日: 2023-12-13)

主引用文献

Schuettelkopf, A.W.,Harrison, J.A.,Boxer, D.H.,Hunter, W.N.
Passive Acquisition of Ligand by the Mopii Molbindin from Clostridium Pasteurianum: Structures of Apo and Oxyanion-Bound Forms
J.Biol.Chem., 277:15013-, 2002

PubMed Abstract: MopII from Clostridium pasteurianum is a molbindin family member. These proteins may serve as intracellular storage facilities for molybdate, which they bind with high specificity. High resolution structures of MopII in a number of states, including the first structure of an apo-molbindin, together with calorimetric data, allow us to describe ligand binding and provide support for the proposed storage function of the protein. MopII assembles as a trimer of dimers and binds eight oxyanions at two types of binding sites located at intersubunit interfaces. Two type 1 sites are on the molecular 3-fold axis and three pairs of type 2 sites occur on the molecular 2-fold axes. The hexamer is largely unaffected by the binding of ligand. Molybdate is admitted to the otherwise inaccessible type 2 binding sites by the movement of the N-terminal residues of each protein chain. This contrasts with the structurally related molybdate-dependent transcriptional regulator ModE, which undergoes extensive conformational rearrangements on ligand binding. Despite similarities between the binding sites of ModE and the type 2 sites of MopII the molbindin has a significantly reduced ligand affinity, due, in part, to the high density of negative charges at the center of the hexamer. In the absence of ligand this effects the movement of an important lysine side chain, thereby partially inactivating the binding sites. The differences are consistent with a biological role in molybdate storage/buffering.

PubMed: 11836258
DOI: 10.1074/JBC.M201005200

実験手法

X-RAY DIFFRACTION (1.83 Å)