3EMR

Crystal Structure Analysis of the ectoine hydroxylase ECTD from Salibacillus salexigens

3EMR の概要

• エントリーDOI: 10.2210/pdb3emr/pdb
• 分子名称: EctD, FE (III) ION, SULFATE ION, ... (5 entities in total)
• 機能のキーワード: double stranded beta helix, oxidoreductase
• 由来する生物種: Virgibacillus salexigens (Salibacillus salexigens)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 36604.38

構造登録者

Reuter, K.,Heine, A. (登録日: 2008-09-25, 公開日: 2009-09-29, 最終更新日: 2024-10-30)

主引用文献

Reuter, K.,Pittelkow, M.,Bursy, J.,Heine, A.,Craan, T.,Bremer, E.
Synthesis of 5-hydroxyectoine from ectoine: crystal structure of the non-heme iron(II) and 2-oxoglutarate-dependent dioxygenase EctD
Plos One, 5:e10647-e10647, 2010

PubMed Abstract: As a response to high osmolality, many microorganisms synthesize various types of compatible solutes. These organic osmolytes aid in offsetting the detrimental effects of low water activity on cell physiology. One of these compatible solutes is ectoine. A sub-group of the ectoine producer's enzymatically convert this tetrahydropyrimidine into a hydroxylated derivative, 5-hydroxyectoine. This compound also functions as an effective osmostress protectant and compatible solute but it possesses properties that differ in several aspects from those of ectoine. The enzyme responsible for ectoine hydroxylation (EctD) is a member of the non-heme iron(II)-containing and 2-oxoglutarate-dependent dioxygenases (EC 1.14.11). These enzymes couple the decarboxylation of 2-oxoglutarate with the formation of a high-energy ferryl-oxo intermediate to catalyze the oxidation of the bound organic substrate. We report here the crystal structure of the ectoine hydroxylase EctD from the moderate halophile Virgibacillus salexigens in complex with Fe(3+) at a resolution of 1.85 A. Like other non-heme iron(II) and 2-oxoglutarate dependent dioxygenases, the core of the EctD structure consists of a double-stranded beta-helix forming the main portion of the active-site of the enzyme. The positioning of the iron ligand in the active-site of EctD is mediated by an evolutionarily conserved 2-His-1-carboxylate iron-binding motif. The side chains of the three residues forming this iron-binding site protrude into a deep cavity in the EctD structure that also harbours the 2-oxoglutarate co-substrate-binding site. Database searches revealed a widespread occurrence of EctD-type proteins in members of the Bacteria but only in a single representative of the Archaea, the marine crenarchaeon Nitrosopumilus maritimus. The EctD crystal structure reported here can serve as a template to guide further biochemical and structural studies of this biotechnologically interesting enzyme family.

PubMed: 20498719
DOI: 10.1371/journal.pone.0010647

実験手法

X-RAY DIFFRACTION (1.85 Å)