The desert of Tataouine: an extreme environment that hosts a wide diversity of microorganisms and radiotolerant bacteria
The desert of Tataouine: an extreme environment that hosts a wide diversity of microorganisms and radiotolerant bacteria
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DOI：
10.1111/j.1462-2920.2005.00921.x
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发表时间：
2006-03-01
影响因子：
5.1
通讯作者：
Heulin, T
中科院分区：
文献类型：
--
作者：
Chanal, A;Chapon, V;Heulin, T
暴露于干旱条件下的塔塔乌因（突尼斯南部）炎热的沙漠中的原核生物群落的系统发育多样性估计与文化和-分子为基础的分析相结合。31个菌株，每个优势形态型的代表，隶属于放线菌，厚壁菌门，变形菌和CFB组，而没有相关的degreea。16 S rRNA基因文库的分析揭示了与细菌和真菌相关的物种的存在。相关序列均归属于非嗜热泉古菌亚群。细菌序列主要由变形菌门、放线菌门和酸杆菌门组成;少数序列分布在其他8个门中，包括栖热菌属/异常球菌属亲属。耐辐射细菌Deinococcus radiodurans的耐干燥性和耐辐射性之间存在相关性。由于生活在塔塔乌因炎热沙漠中的细菌以某种方式耐受干燥，我们研究它们是否也能耐受辐射。将土壤样本暴露于强γ辐射中，会产生芽孢杆菌、栖热菌/异常球菌和α-变形菌门近缘种。这些菌株中有4种对应于通过评价单个培养物的抗性水平所揭示的耐辐射种属。对两个栖热菌属/异常球菌属和两个α-变形菌门亲属的抗性水平的详细分析表明，它们对应于新的耐辐射物种。
The phylogenetic diversity of prokaryotic communities exposed to arid conditions in the hot desert of Tataouine (south Tunisia) was estimated with a combination of a culture and - molecular-based analysis. Thirty-one isolates, representative of each dominant morphotypes, were affiliated to Actinobacteria, Firmicutes, Proteobacteria and the CFB group while none related to Archaea. Analysis of 16S rRNA gene libraries revealed the presence of species related to Bacteria and Archaea. Sequences related to Archaea were all affiliated to the non-thermophilic Crenarchaeota subgroup. Bacterial sequences were dominated by Proteobacteria, Actinobacteria and Acidobacteria; a few sequences were distributed among eight others phyla, including Thermus/Deinococcus relatives. A correlation between tolerance to desiccation and to radiation has been demonstrated for the radiotolerant bacteria Deinococcus radiodurans. Because bacteria living in the hot desert of Tataouine are one way or another tolerant to desiccation, we investigate whether they could also be tolerant to radiation. Exposition of soil samples to intense gamma radiation yields Bacillus, Thermus/Deinococcus and alpha-Proteobacteria relatives. Four of these strains correspond to radiotolerant species as revealed by evaluation of the resistance levels of the individual cultures. A detailed analysis of the resistance levels for two Thermus/Deinococcus and two alpha-Proteobacteria relatives revealed that they correspond to new radiotolerant species.