5KF7

Structure of proline utilization A from Sinorhizobium meliloti complexed with L-tetrahydrofuroic acid and NAD+ in space group P3121

5KF7 の概要

• エントリーDOI: 10.2210/pdb5kf7/pdb
• 関連するPDBエントリー: 5KF6
• 分子名称: Bifunctional protein PutA, FLAVIN-ADENINE DINUCLEOTIDE, NICOTINAMIDE-ADENINE-DINUCLEOTIDE, ... (10 entities in total)
• 機能のキーワード: flavoenzyme, rossmann fold, aldehyde dehydrogenase, proline catabolism, substrate channeling, bifunctional enzyme, oxidoreductase
• 由来する生物種: Sinorhizobium meliloti (strain SM11)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 134468.07

構造登録者

Tanner, J.J. (登録日: 2016-06-12, 公開日: 2016-10-05, 最終更新日: 2023-09-27)

主引用文献

Luo, M.,Gamage, T.T.,Arentson, B.W.,Schlasner, K.N.,Becker, D.F.,Tanner, J.J.
Structures of Proline Utilization A (PutA) Reveal the Fold and Functions of the Aldehyde Dehydrogenase Superfamily Domain of Unknown Function.
J.Biol.Chem., 291:24065-24075, 2016

PubMed Abstract: Aldehyde dehydrogenases (ALDHs) catalyze the NAD(P)-dependent oxidation of aldehydes to carboxylic acids and are important for metabolism and detoxification. Although the ALDH superfamily fold is well established, some ALDHs contain an uncharacterized domain of unknown function (DUF) near the C terminus of the polypeptide chain. Herein, we report the first structure of a protein containing the ALDH superfamily DUF. Proline utilization A from Sinorhizobium meliloti (SmPutA) is a 1233-residue bifunctional enzyme that contains the DUF in addition to proline dehydrogenase and l-glutamate-γ-semialdehyde dehydrogenase catalytic modules. Structures of SmPutA with a proline analog bound to the proline dehydrogenase site and NAD bound to the ALDH site were determined in two space groups at 1.7-1.9 Å resolution. The DUF consists of a Rossmann dinucleotide-binding fold fused to a three-stranded β-flap. The Rossmann domain resembles the classic ALDH superfamily NAD-binding domain, whereas the flap is strikingly similar to the ALDH superfamily dimerization domain. Paradoxically, neither structural element performs its implied function. Electron density maps show that NAD does not bind to the DUF Rossmann fold, and small-angle X-ray scattering reveals a novel dimer that has never been seen in the ALDH superfamily. The structure suggests that the DUF is an adapter domain that stabilizes the aldehyde substrate binding loop and seals the substrate-channeling tunnel via tertiary structural interactions that mimic the quaternary structural interactions found in non-DUF PutAs. Kinetic data for SmPutA indicate a substrate-channeling mechanism, in agreement with previous studies of other PutAs.

PubMed: 27679491
DOI: 10.1074/jbc.M116.756965

実験手法

X-RAY DIFFRACTION (1.9 Å)