Uracil-DNA glycosylase in the extreme thermophile Archaeoglobus fulgidus
Uracil-DNA glycosylase in the extreme thermophile Archaeoglobus fulgidus
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DOI：
10.1074/jbc.m001995200
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发表时间：
2000-06-23
影响因子：
4.8
通讯作者：
Franklin, WA
中科院分区：
文献类型：
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作者：
Sandigursky, M;Franklin, WA
尿嘧啶-DNA糖基酶(UDG)是维持基因组完整性的重要酶。在这里，我们描述了一种来自极端嗜热古生菌的UDG。该酶是原核生物中发现的一类新的酶的成员，不同于在大肠杆菌、真核生物和含DNA的病毒中发现的UDG酶。黄曲霉UDG：具有极高的热稳定性，在95℃加热1.5小时后保持全部活性。该蛋白能够从含有U/A或U/G碱基对的双链DNA以及单链DNA中去除尿嘧啶。该酶的产物受尿嘧啶和脱嘌呤/脱嘧啶位点的抑制。黄曲霉UDG在初级氨基酸序列水平上与嗜热真细菌Thermotoga maritima中的酶有高度的相似性，表明UDG启动的碱基切除修复在古生菌和嗜热真细菌中具有保守的机制。
Uracil-DNA glycosylase (UDG) is an essential enzyme for maintaining genomic integrity. Here we describe a UDG from the extreme thermophile Archaeoglobus fulgidus. The enzyme is a member of a new class of enzymes found in prokaryotes that is distinct from the UDG enzyme found in Escherichia coli, eukaryotes, and DNA-containing viruses. The A. fulgidus UDG: is extremely thermostable, maintaining full activity after heating for 1.5 h at 95 degrees C. The protein is capable of removing uracil from double-stranded DNA containing either a U/A or U/G base pair as well as from single-stranded DNA. This enzyme is product-inhibited by both uracil and apurinic/apyrimidinic sites. The A. fulgidus UDG has a high degree of similarity at the primary amino acid sequence level to the enzyme found in Thermotoga maritima, a thermophilic eubacteria, and suggests a conserved mechanism of UDG-initiated base excision repair in archaea and thermophilic eubacteria.