456D

MOLECULAR AND CRYSTAL STRUCTURE OF D(CGCGMO6AATCCGCG): THE WATSON-CRICK TYPE N6-METHOXYADENOSINE/CYTIDINE BASE-PAIRS IN B-DNA

456D の概要

• エントリーDOI: 10.2210/pdb456d/pdb
• 分子名称: DNA (5'-D(*CP*GP*CP*GP*(A47)P*AP*TP*CP*CP*GP*CP*G)-3'), MAGNESIUM ION (3 entities in total)
• 機能のキーワード: modified nucleotide, mismatch, methoxyadenosine, dna damage, b-dna, double helix, dna
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 7381.12

構造登録者

Chatake, T.,Ono, A.,Ueno, Y.,Matsuda, A.,Takenaka, A. (登録日: 1999-03-06, 公開日: 2000-01-01, 最終更新日: 2023-12-27)

主引用文献

Chatake, T.,Ono, A.,Ueno, Y.,Matsuda, A.,Takenaka, A.
Crystallographic studies on damaged DNAs. I. An N(6)-methoxyadenine residue forms a Watson-Crick pair with a cytosine residue in a B-DNA duplex.
J.Mol.Biol., 294:1215-1222, 1999

PubMed Abstract: Oxyamines such as hydroxylamine and methoxylamine disturb DNA replication and act as potent mutagens, causing nucleotide transition from one purine to another or one pyrimidine to another. In order to investigate mismatch base-pairing in DNA damaged with oxyamines, a dodecamer with the sequence d(CGCGmo(6)AATCCGCG), where mo(6) A is 2'-deoxy-N(6)-methoxyadenosine, was synthesized and its crystal structure determined. No significant conformational changes are found between the present dodecamer and the original undamaged B-form dodecamer. Electron density maps clearly show that the mo(6)A residue forms a base-pair with a 2'-deoxycytidine residue through hydrogen bonds similar to a Watson-Crick G.C base-pair. For these hydrogen bonds to be made, N(6)-methoxyadenine must chemically take the imino form. The methoxylation thus enables the adenine base to mimic a guanine base. As a result, misincorporation of 2'-deoxycytidine instead of thymidine, or 2'-deoxyadenosine instead of 2'-deoxyguanosine, can occur in DNA replication.

PubMed: 10600379
DOI: 10.1006/jmbi.1999.3303

実験手法

X-RAY DIFFRACTION (1.6 Å)