1QJO

INNERMOST LIPOYL DOMAIN OF THE PYRUVATE DEHYDROGENASE FROM ESCHERICHIA COLI

1QJO の概要

• エントリーDOI: 10.2210/pdb1qjo/pdb
• 関連するPDBエントリー: 1DPC
• 分子名称: DIHYDROLIPOAMIDE ACETYLTRANSFERASE (1 entity in total)
• 機能のキーワード: dihydrolipoamide acetyltransferase, lipoyl domain, pyruvate dehydrogenase
• 由来する生物種: ESCHERICHIA COLI BL21(DE3)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 8380.67

構造登録者

Jones, D.D.,Howard, M.J.,Perham, R.N. (登録日: 1999-06-29, 公開日: 1999-06-30, 最終更新日: 2024-05-15)

主引用文献

Jones, D.D.,Stott, K.M.,Howard, M.J.,Perham, R.N.
Restricted motion of the lipoyl-lysine swinging arm in the pyruvate dehydrogenase complex of Escherichia coli.
Biochemistry, 39:8448-8459, 2000

PubMed Abstract: The three lipoyl (E2plip) domains of the dihydrolipoyl acetyltransferase component of the pyruvate dehydrogenase (PDH) complex of Escherichia coli house the lipoyl-lysine side chain essential for active-site coupling and substrate channelling within the complex. The structure of the unlipoylated form of the innermost domain (E2plip(apo)) was determined by multidimensional NMR spectroscopy and found to resemble closely that of a nonfunctional hybrid domain determined previously [Green et al. (1995) J. Mol. Biol. 248, 328-343]. The domain comprises two four-stranded beta-sheets, with the target lysine residue residing at the tip of a type-I beta-turn in one of the sheets; the N- and C-termini lie close together at the opposite end of the molecule in the other beta-sheet. Measurement of (15)N NMR relaxation parameters and backbone hydrogen/deuterium (H/D) exchange rates reveals that the residues in and surrounding the lipoyl-lysine beta-turn in the E2plip(apo) form of the domain become less flexible after lipoylation of the lysine residue. This implies that the lipoyl-lysine side chain may not sample the full range of conformational space once thought. Moreover, reductive acetylation of the lipoylated domain (E2plip(holo) --> E2plip(redac)) was accompanied by large changes in chemical shift between the two forms, and multiple resonances were observed for several residues. This implies a change in conformation and the existence of multiple conformations of the domain on reductive acetylation, which may be important in stabilizing this catalytic intermediate.

PubMed: 10913250
DOI: 10.1021/BI992978I

実験手法

SOLUTION NMR