2Q2Q

Structure of D-3-Hydroxybutyrate Dehydrogenase from Pseudomonas putida

2Q2Q の概要

• エントリーDOI: 10.2210/pdb2q2q/pdb
• 分子名称: Beta-D-hydroxybutyrate dehydrogenase, NICOTINAMIDE-ADENINE-DINUCLEOTIDE (3 entities in total)
• 機能のキーワード: pseudomonas putida, sdr, oxidoreductase
• 由来する生物種: Pseudomonas putida
• タンパク質・核酸の鎖数: 8
• 化学式量合計: 216038.75

構造登録者

Paithankar, K.S.,Feller, C.,Kuettner, E.B.,Keim, A.,Grunow, M.,Strater, N. (登録日: 2007-05-29, 公開日: 2007-10-30, 最終更新日: 2023-08-30)

主引用文献

Paithankar, K.S.,Feller, C.,Kuettner, E.B.,Keim, A.,Grunow, M.,Strater, N.
Cosubstrate-induced dynamics of D-3-hydroxybutyrate dehydrogenase from Pseudomonas putida.
Febs J., 274:5767-5779, 2007

PubMed Abstract: D-3-Hydroxybutyrate dehydrogenase from Pseudomonas putida belongs to the family of short-chain dehydrogenases/reductases. We have determined X-ray structures of the D-3-hydroxybutyrate dehydrogenase from Pseudomonas putida, which was recombinantly expressed in Escherichia coli, in three different crystal forms to resolutions between 1.9 and 2.1 A. The so-called substrate-binding loop (residues 187-210) was partially disordered in several subunits, in both the presence and absence of NAD(+). However, in two subunits, this loop was completely defined in an open conformation in the apoenzyme and in a closed conformation in the complex structure with NAD(+). Structural comparisons indicated that the loop moves as a rigid body by about 46 degrees . However, the two small alpha-helices (alphaFG1 and alphaFG2) of the loop also re-orientated slightly during the conformational change. Probably, the interactions of Val185, Thr187 and Leu189 with the cosubstrate induced the conformational change. A model of the binding mode of the substrate D-3-hydroxybutyrate indicated that the loop in the closed conformation, as a result of NAD(+) binding, is positioned competent for catalysis. Gln193 is the only residue of the substrate-binding loop that interacts directly with the substrate. A translation, libration and screw (TLS) analysis of the rigid body movement of the loop in the crystal showed significant librational displacements, describing the coordinated movement of the substrate-binding loop in the crystal. NAD(+) binding increased the flexibility of the substrate-binding loop and shifted the equilibrium between the open and closed forms towards the closed form. The finding that all NAD(+) -bound subunits are present in the closed form and all NAD(+) -free subunits in the open form indicates that the loop closure is induced by cosubstrate binding alone. This mechanism may contribute to the sequential binding of cosubstrate followed by substrate.

PubMed: 17958702
DOI: 10.1111/j.1742-4658.2007.06102.x

実験手法

X-RAY DIFFRACTION (2.02 Å)