Kaur B, Avery A M, Doetsch P W
Department of Biochemistry, Division of Cancer Biology, Radiation and Oncology, Emory University School of Medicine, Atlanta, Georgia 30322, USA.
Biochemistry. 1998 Aug 18;37(33):11599-604. doi: 10.1021/bi981008c.
Ultraviolet damage endonuclease (UVDE) is a 68.7 kDa DNA repair enzyme of Schizosaccharomyces pombe that recognizes cyclobutane pyrimidine dimers (CPDs) and 6-4 photoproducts (6-4 PPs). UVDE is thought to initiate the first step in an alternative excision repair pathway for removal of UV light-induced DNA damage. We have overexpressed Delta228-UVDE, an active truncated form of UVDE, and have purified this protein to apparent homogeneity. We have characterized purified Delta228-UVDE with respect to its physical properties, divalent cation requirements, and kinetic parameters on oligodeoxynucleotide substrates containing a single CPD. DNA strand cleavage analysis indicates that both full-length UVDE and Delta228-UVDE incise the CPD-containing strand immediately 5' to the lesion. These results provide further insight into the UVDE-mediated alternative excision repair pathway.
紫外线损伤内切核酸酶（UVDE）是粟酒裂殖酵母的一种68.7 kDa的DNA修复酶，可识别环丁烷嘧啶二聚体（CPD）和6-4光产物（6-4PP）。UVDE被认为是启动替代切除修复途径第一步的酶，该途径用于去除紫外线诱导的DNA损伤。我们已经过表达了Delta228-UVDE，这是UVDE的一种活性截短形式，并将该蛋白纯化至表观均一性。我们已经对纯化的Delta228-UVDE的物理性质、二价阳离子需求以及在含有单个CPD的寡脱氧核苷酸底物上的动力学参数进行了表征。DNA链切割分析表明，全长UVDE和Delta228-UVDE均在损伤位点5'端紧邻处切割含CPD的链。这些结果为UVDE介导的替代切除修复途径提供了进一步的见解。
