来自集胞藻的光复活酶对含有胸腺嘧啶二聚体的DNA八聚体d(GCGTTGCG).d(CGCAACGC)的光复活作用

Photoreactivation of the thymine dimer containing DNA octamer d(GCGTTGCG).d(CGCAACGC) by the photoreactivating enzyme from Anacystis nidulans.

作者信息

Kemmink J, Eker A P, van der Marel G A, van Boom J H, Kaptein R

机构信息

Department of Physical Chemistry, University of Groningen, The Netherlands.

出版信息

J Photochem Photobiol B. 1988 Mar;1(3):323-8. doi: 10.1016/1011-1344(88)85020-6.

DOI:10.1016/1011-1344(88)85020-6

PMID:3149667

Abstract

Irradiation of the double-stranded octamer d(GCGTTGCG).d(CGCAACGC) with UV light causes dimerization of the two central thymine residues. Proton NMR data reveal that this photodimer has the same chemical structure as the photodimer, which is formed upon UV irradiation of the single strand d(GCGTTGCG), a cis-syn-cyclobutane-type thymine dimer. Irradiation of the purified thymine dimer double-stranded octamer d(GCGTTGCG).d(CGCAACGC) with visible light in the presence of photoreactivating enzyme isolated from Anacystis nidulans leads to an increase in absorbance at 260 nm, which is characteristic for the repair of thymine dimers. The NMR spectrum recorded after the photoreactivating treatment indeed shows that a complete conversion to the starting octamer has occurred.

摘要

用紫外光照射双链八聚体d(GCGTTGCG).d(CGCAACGC)会导致两个中心胸腺嘧啶残基发生二聚化。质子核磁共振数据表明，这种光二聚体具有与单链d(GCGTTGCG)经紫外光照射形成的光二聚体相同的化学结构，即顺式-顺式-环丁烷型胸腺嘧啶二聚体。在存在从集胞藻中分离出的光复活酶的情况下，用可见光照射纯化的胸腺嘧啶二聚体双链八聚体d(GCGTTGCG).d(CGCAACGC)，会导致260nm处吸光度增加，这是胸腺嘧啶二聚体修复的特征。光复活处理后记录的核磁共振谱确实表明已完全转化为起始的八聚体。