1DIZ

CRYSTAL STRUCTURE OF E. COLI 3-METHYLADENINE DNA GLYCOSYLASE (ALKA) COMPLEXED WITH DNA

1DIZ の概要

• エントリーDOI: 10.2210/pdb1diz/pdb
• 分子名称: DNA (5'-D(*GP*AP*CP*AP*TP*GP*AP*(NRI)P*TP*GP*CP*CP*T)-3'), DNA (5'-D(*GP*GP*CP*AP*AP*TP*CP*AP*TP*GP*TP*CP*A)-3'), 3-METHYLADENINE DNA GLYCOSYLASE II, ... (5 entities in total)
• 機能のキーワード: 3-methyladenine dna glycosylase, alka, helix-hairpin-helix, protein-dna complex, 1-azaribose, hydrolase-dna complex, hydrolase/dna
• 由来する生物種: Escherichia coli; 詳細
• タンパク質・核酸の鎖数: 6
• 化学式量合計: 78530.70

構造登録者

Hollis, T.,Ichikawa, Y.,Ellenberger, T.E. (登録日: 1999-11-30, 公開日: 2000-03-20, 最終更新日: 2024-02-07)

主引用文献

Hollis, T.,Ichikawa, Y.,Ellenberger, T.
DNA bending and a flip-out mechanism for base excision by the helix-hairpin-helix DNA glycosylase, Escherichia coli AlkA.
EMBO J., 19:758-766, 2000

PubMed Abstract: The Escherichia coli AlkA protein is a base excision repair glycosylase that removes a variety of alkylated bases from DNA. The 2.5 A crystal structure of AlkA complexed to DNA shows a large distortion in the bound DNA. The enzyme flips a 1-azaribose abasic nucleotide out of DNA and induces a 66 degrees bend in the DNA with a marked widening of the minor groove. The position of the 1-azaribose in the enzyme active site suggests an S(N)1-type mechanism for the glycosylase reaction, in which the essential catalytic Asp238 provides direct assistance for base removal. Catalytic selectivity might result from the enhanced stacking of positively charged, alkylated bases against the aromatic side chain of Trp272 in conjunction with the relative ease of cleaving the weakened glycosylic bond of these modified nucleotides. The structure of the AlkA-DNA complex offers the first glimpse of a helix-hairpin-helix (HhH) glycosylase complexed to DNA. Modeling studies suggest that other HhH glycosylases can bind to DNA in a similar manner.

PubMed: 10675345
DOI: 10.1093/emboj/19.4.758

実験手法

X-RAY DIFFRACTION (2.5 Å)