3GGG

The crystal structure of A. aeolicus prephenate dehydrogenase in complex with tyrosine and NAD+

3GGG の概要

• エントリーDOI: 10.2210/pdb3ggg/pdb
• 関連するPDBエントリー: 3GGO 3GGP
• 分子名称: Prephenate dehydrogenase, NICOTINAMIDE-ADENINE-DINUCLEOTIDE, TYROSINE, ... (4 entities in total)
• 機能のキーワード: dinucleotide binding fold, beta-alpha, tyrosine-bound, nad, oxidoreductase
• 由来する生物種: Aquifex aeolicus
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 144071.17

構造登録者

Sun, W.,Shahinas, D.,Christendat, D. (登録日: 2009-02-27, 公開日: 2009-03-10, 最終更新日: 2023-09-06)

主引用文献

Sun, W.,Shahinas, D.,Bonvin, J.,Hou, W.,Kimber, M.S.,Turnbull, J.,Christendat, D.
The Crystal Structure of Aquifex aeolicus Prephenate Dehydrogenase Reveals the Mode of Tyrosine Inhibition.
J.Biol.Chem., 284:13223-13232, 2009

PubMed Abstract: TyrA proteins belong to a family of dehydrogenases that are dedicated to l-tyrosine biosynthesis. The three TyrA subclasses are distinguished by their substrate specificities, namely the prephenate dehydrogenases, the arogenate dehydrogenases, and the cyclohexadienyl dehydrogenases, which utilize prephenate, l-arogenate, or both substrates, respectively. The molecular mechanism responsible for TyrA substrate selectivity and regulation is unknown. To further our understanding of TyrA-catalyzed reactions, we have determined the crystal structures of Aquifex aeolicus prephenate dehydrogenase bound with NAD(+) plus either 4-hydroxyphenylpyuvate, 4-hydroxyphenylpropionate, or l-tyrosine and have used these structures as guides to target active site residues for site-directed mutagenesis. From a combination of mutational and structural analyses, we have demonstrated that His-147 and Arg-250 are key catalytic and binding groups, respectively, and Ser-126 participates in both catalysis and substrate binding through the ligand 4-hydroxyl group. The crystal structure revealed that tyrosine, a known inhibitor, binds directly to the active site of the enzyme and not to an allosteric site. The most interesting finding though, is that mutating His-217 relieved the inhibitory effect of tyrosine on A. aeolicus prephenate dehydrogenase. The identification of a tyrosine-insensitive mutant provides a novel avenue for designing an unregulated enzyme for application in metabolic engineering.

PubMed: 19279014
DOI: 10.1074/jbc.M806272200

実験手法

X-RAY DIFFRACTION (2.21 Å)