Kumari Bhavini, DAS Prolay, Kumari Rekha
Department of Chemistry, IIT Patna, Patna, India.
J Biosci. 2016 Jun;41(2):265-75. doi: 10.1007/s12038-016-9614-0.
The stimulatory effect of the aqueous extract of G. lucidum, a basidiomycetes class fungus in the APE1-enzyme-mediated processing of solitary and bistranded clustered abasic sites DNA damages is presented. Abasic sites are considered the most common type of DNA damage lesions. Our study shows enhanced activity of APE1 in the processing of abasic sites in the presence of the polysaccharides fraction of G. lucidum. Remarkable increase in the amount of single-strand breaks (SSBs) and double-strand breaks (DSBs) from solitary and bistranded clustered abasic sites respectively with APE1 in the presence of the extract was found. This trend is maintained when abasic sites in DNA oligomers are exposed to fibroblast cell extracts in the presence of the extract. While DNA conformational alteration is negligible, APE1 enzyme shows characteristic changes in the alpha helix and beta strand ratio after incubation with G. lucidum extract. The enhanced reactivity of APE1 at the molecular level in the presence of G. lucidium is attributed to this effect. This study potentially amplifies the scope of the use of G. lucidum, which was earlier shown to have only reactive oxygen species (ROS) scavenging properties with regards to DNA damage inhibition.
本文介绍了担子菌类真菌灵芝水提取物在猿猴空泡病毒1型（APE1）酶介导的单链和双链簇状无碱基位点DNA损伤处理中的刺激作用。无碱基位点被认为是最常见的DNA损伤类型。我们的研究表明，在灵芝多糖组分存在的情况下，APE1在处理无碱基位点时活性增强。发现在提取物存在的情况下，APE1分别使单链和双链簇状无碱基位点产生的单链断裂（SSB）和双链断裂（DSB）数量显著增加。当DNA寡聚物中的无碱基位点在提取物存在的情况下暴露于成纤维细胞提取物时，这种趋势得以维持。虽然DNA构象改变可忽略不计，但APE1酶在与灵芝提取物孵育后，其α螺旋和β链比例呈现出特征性变化。在灵芝存在的情况下，APE1在分子水平上增强的反应性归因于此效应。本研究可能扩大了灵芝的应用范围，此前研究表明灵芝在抑制DNA损伤方面仅具有清除活性氧（ROS）的特性。
