Liu Yang, Cui Xiaowen, Yang Ruiqi, Zhang Yiyang, Xu Yeteng, Liu Guangxiu, Zhang Binglin, Wang Jinxiu, Wang Xinyue, Zhang Wei, Chen Tuo, Zhang Gaosen
State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China.
University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China.
Microorganisms. 2022 Oct 14;10(10):2037. doi: 10.3390/microorganisms10102037.
Mount Everest provides natural advantages to finding radiation-resistant extremophiles that are functionally mechanistic and possess commercial significance. (1) Background: Two bacterial strains, designated S5-59T and S8-45T, were isolated from moraine samples collected from the north slope of Mount Everest at altitudes of 5700m and 5100m above sea level. (2) Methods: The present study investigated the polyphasic features and genomic characteristics of S5-59 and S8-45. (3) Results: The major fatty acids and the predominant respiratory menaquinone of S5-59 and S8-45 were summed as feature 3 (comprising C16:1 6c and/or C16:1 7c) and ubiquinone-10 (Q-10). Phylogenetic analyses based on 16S rRNA sequences and average nucleotide identity values among these two strains and their reference type strains were below the species demarcation thresholds of 98.65% and 95%. Strains S5-59 and S8-45 harbored great radiation resistance. The genomic analyses showed that DNA damage repair genes, such as , , , , , , etc., were present in the S5-59 and S8-45 strains. Additionally, strain S5-59 possessed more genes related to DNA protection proteins. The pan-genome analysis and horizontal gene transfers revealed that strains of had a consistently homologous genetic evolutionary radiation resistance. Moreover, enzymatic antioxidative proteins also served critical roles in converting ROS into harmless molecules that resulted in resistance to radiation. Further, pigments and carotenoids such as zeaxanthin and alkylresorcinols of the non-enzymatic antioxidative system were also predicted to protect them from radiation. (4) Conclusions: Type strains S5-59 (=JCM 35564T =GDMCC 1.3193T) and S8-45 (=JCM 34749T =GDMCC 1.2715T) represent two novel species of the genus with the proposed name sp. nov. and sp. nov. The type strains, S5-59 and S8-45, were assessed in a deeply genomic study of their radiation-resistant mechanisms and this thus resulted in a further understanding of their greater potential application for the development of anti-radiation protective drugs.
珠穆朗玛峰为寻找具有功能机制且具有商业意义的抗辐射极端微生物提供了天然优势。（1）背景：从珠穆朗玛峰北坡海拔5700米和5100米处采集的冰碛样本中分离出两株细菌，分别命名为S5 - 59T和S8 - 45T。（2）方法：本研究调查了S5 - 59和S8 - 45的多相特征和基因组特征。（3）结果：S5 - 59和S8 - 45的主要脂肪酸和主要呼吸醌分别总结为特征3（包含C16:1 6c和/或C16:1 7c）和泛醌 - 10（Q - 10）。基于16S rRNA序列以及这两株菌株与其参考模式菌株之间的平均核苷酸同一性值的系统发育分析低于98.65%和95%的物种划分阈值。菌株S5 - 59和S8 - 45具有很强的抗辐射能力。基因组分析表明，S5 - 59和S8 - 45菌株中存在诸如 、 、 、 、 、 等DNA损伤修复基因。此外，菌株S5 - 59拥有更多与DNA保护蛋白相关的基因。泛基因组分析和水平基因转移表明， 的菌株具有一致的同源遗传进化抗辐射能力。此外，酶促抗氧化蛋白在将活性氧转化为无害分子从而产生抗辐射能力方面也发挥着关键作用。此外，非酶促抗氧化系统的色素和类胡萝卜素，如玉米黄质和烷基间苯二酚，也被预测可保护它们免受辐射。（4）结论：模式菌株S5 - 59（=JCM 35564T =GDMCC 1.3193T）和S8 - 45（=JCM 34749T =GDMCC 1.2715T）代表 属的两个新物种，提议命名为 新种和 新种。对模式菌株S5 - 59和S8 - 45进行了深入的基因组研究，以评估它们的抗辐射机制，从而进一步了解它们在开发抗辐射保护药物方面的更大潜在应用价值。
需注意，原文中部分基因名称未给出具体内容，用“ ”代替了，翻译时保留原样。
