Koulis A, Cowan D A, Pearl L H, Savva R
Department of Biochemistry and Molecular Biology, University College London, UK.
FEMS Microbiol Lett. 1996 Oct 1;143(2-3):267-71. doi: 10.1111/j.1574-6968.1996.tb08491.x.
Hyperthermophiles exist in conditions which present an increased threat to the informational integrity of their DNA, particularly by hydrolytic damage. As in mesophilic organisms, specific activities must exist to restore and protect this template function of DNA. In this study we have demonstrated the presence of thermally stable uracil-DNA glycosylase activities in seven hyperthermophiles; one bacterial: Thermotoga maritima, and six archaeal: Sulfolobus solfataricus, Sulfolobus shibatae, Sulfolobus acidocaldarius, Thermococcus litoralis, Pyrococcus furiosus and Pyrobaculum islandicum. Uracil-DNA glycosylase inhibitor protein of the Bacillus subtilis bacteriophage PBS1 shows activity against all of these, suggesting a highly conserved tertiary structure between hyperthermophilic and mesophilic uracil-DNA glycosylases.
嗜热菌生存的环境对其DNA的信息完整性构成了更大的威胁，尤其是水解损伤。与嗜温生物一样，必须存在特定的活性来恢复和保护DNA的这种模板功能。在本研究中，我们已经证明在七种嗜热菌中存在热稳定的尿嘧啶-DNA糖基化酶活性；一种细菌：嗜热栖热菌，以及六种古菌：嗜热栖热菌、柴田硫化叶菌、嗜酸硫化叶菌、嗜热栖热球菌、激烈火球菌和海岛嗜热栖热菌。枯草芽孢杆菌噬菌体PBS1的尿嘧啶-DNA糖基化酶抑制蛋白对所有这些酶都有活性，这表明嗜热和嗜温尿嘧啶-DNA糖基化酶之间存在高度保守的三级结构。
