4YR9

mouse TDH with NAD+ bound

4YR9 の概要

• エントリーDOI: 10.2210/pdb4yr9/pdb
• 関連するPDBエントリー: 4YRA 4YRB
• 分子名称: L-threonine 3-dehydrogenase, mitochondrial, NICOTINAMIDE-ADENINE-DINUCLEOTIDE, GLYCEROL, ... (4 entities in total)
• 機能のキーワード: l-threonine 3-dehydrogenase, oxidoreductase
• 由来する生物種: Mus musculus (Mouse)
• 細胞内の位置: Mitochondrion : Q8K3F7
• タンパク質・核酸の鎖数: 6
• 化学式量合計: 224666.18

構造登録者

He, C.,Li, F. (登録日: 2015-03-14, 公開日: 2016-02-03, 最終更新日: 2023-11-08)

主引用文献

He, C.,Huang, X.,Liu, Y.,Li, F.,Yang, Y.,Tao, H.,Han, C.,Zhao, C.,Xiao, Y.,Shi, Y.
Structural insights on mouse l-threonine dehydrogenase: A regulatory role of Arg180 in catalysis
J.Struct.Biol., 192:510-518, 2015

PubMed Abstract: Mouse L-threonine dehydrogenase (mTDH), which belongs to the short-chain dehydrogenase/reductase (SDR) superfamily and mediates threonine catabolism, plays pivotal roles in both powerful biosynthesis and signaling in mouse stem cells and has a regulatory residue Arg180. Here we determined three crystal structures of mTDH: wild-type (WT) in the apo form; in complex with NAD(+) and a substrate analog, glycerol, or with only NAD(+); as well as the R180K variant with NAD(+). This is the first description of a structure for mammalian SDR-type TDH. Structural comparison revealed the structural basis for SDR-type TDH catalysis remains strictly conserved in bacteria and mammals. Kinetic enzyme assays, and isothermal titration calorimetry (ITC) measurements indicated the R180K mutation has little effect on NAD(+) binding affinity, whereas affects the substrate's affinity for the enzyme. The crystal structure of R180K with NAD(+), biochemical and spectroscopic studies suggested that the R180K mutant should bind NAD(+) in a similar way and have a similar folding to the WT. However, the R180K variant may have difficulty adopting the closed form due to reduced interaction of residue 180 with a loop which connects a key position for mTDH switching between the closed and open forms in mTDH catalysis, and thereby exhibited a significantly decreased kcat/Km value toward the substrate, L-Thr. In sum, our results suggest that activity of GalE-like TDH can be regulated by remote interaction, such as hydrogen bonding and hydrophobic interaction around the Arg180 of mTDH.

PubMed: 26492815
DOI: 10.1016/j.jsb.2015.10.014

実験手法

X-RAY DIFFRACTION (2.8 Å)