4I9B

Structure of aminoaldehyde dehydrogenase 1 from Solanum lycopersium (SlAMADH1) with a thiohemiacetal intermediate

4I9B の概要

• エントリーDOI: 10.2210/pdb4i9b/pdb
• 関連するPDBエントリー: 3IWJ 3IWK 4I8P 4I8Q
• 分子名称: Putative betaine aldehyde dehyrogenase, NICOTINAMIDE-ADENINE-DINUCLEOTIDE, SODIUM ION, ... (7 entities in total)
• 機能のキーワード: aldh10 family fold, oxidoreductase
• 由来する生物種: Solanum lycopersicum (tomato)
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 114545.97

構造登録者

Morera, S.,Vigouroux, A.,Kopecny, D. (登録日: 2012-12-05, 公開日: 2013-02-20, 最終更新日: 2024-11-20)

主引用文献

Kopecny, D.,Koncitikova, R.,Tylichova, M.,Vigouroux, A.,Moskalikova, H.,Soural, M.,Sebela, M.,Morera, S.
Plant ALDH10 family: identifying critical residues for substrate specificity and trapping a thiohemiacetal intermediate.
J.Biol.Chem., 288:9491-9507, 2013

PubMed Abstract: Plant ALDH10 family members are aminoaldehyde dehydrogenases (AMADHs), which oxidize ω-aminoaldehydes to the corresponding acids. They have been linked to polyamine catabolism, osmoprotection, secondary metabolism (fragrance), and carnitine biosynthesis. Plants commonly contain two AMADH isoenzymes. We previously studied the substrate specificity of two AMADH isoforms from peas (PsAMADHs). Here, two isoenzymes from tomato (Solanum lycopersicum), SlAMADHs, and three AMADHs from maize (Zea mays), ZmAMADHs, were kinetically investigated to obtain further clues to the catalytic mechanism and the substrate specificity. We also solved the high resolution crystal structures of SlAMADH1 and ZmAMADH1a because these enzymes stand out from the others regarding their activity. From the structural and kinetic analysis, we can state that five residues at positions 163, 288, 289, 444, and 454 (PsAMADHs numbering) can, directly or not, significantly modulate AMADH substrate specificity. In the SlAMADH1 structure, a PEG aldehyde derived from the precipitant forms a thiohemiacetal intermediate, never observed so far. Its absence in the SlAMADH1-E260A structure suggests that Glu-260 can activate the catalytic cysteine as a nucleophile. We show that the five AMADHs studied here are capable of oxidizing 3-dimethylsulfoniopropionaldehyde to the cryo- and osmoprotectant 3-dimethylsulfoniopropionate. For the first time, we also show that 3-acetamidopropionaldehyde, the third aminoaldehyde besides 3-aminopropionaldehyde and 4-aminobutyraldehyde, is generally oxidized by AMADHs, meaning that these enzymes are unique in metabolizing and detoxifying aldehyde products of polyamine degradation to nontoxic amino acids. Finally, gene expression profiles in maize indicate that AMADHs might be important for controlling ω-aminoaldehyde levels during early stages of the seed development.

PubMed: 23408433
DOI: 10.1074/jbc.M112.443952

実験手法

X-RAY DIFFRACTION (1.9 Å)