藤黄微球菌V017基因组测序及对辐照的转录组响应  

Complete genome of Micrococcus luteus V017 and its transcriptomic response to gamma ray radiation

作　　者：孙敏 陈天宇 冯红[1] SUN Min;CHEN Tianyu;FENG Hong(Sichuan Key Laboratory of Molecular Biology and Biotechnology,College of Life Sciences,Sichuan University,Chengdu,Sichuan 610064,China)

机构地区：[1]四川大学生命科学学院四川省分子生物学与生物技术重点实验室,四川成都610064

出　　处：《微生物学通报》2021年第5期1648-1661,共14页Microbiology China

基　　金：四川省科技支撑计划(2016NZ0106)。

摘　　要：【背景】耐辐射微生物是一类重要的极端微生物资源,在研究其耐受机制以及环境保护等方面具有重大的意义。【目的】从基因组和转录组角度解析耐辐射藤黄微球菌(Micrococcus luteus)V017的抗性遗传背景以及对辐照的转录组响应。【方法】利用PacBio平台对菌株V017进行基因组测序,通过比较基因组分析菌株V017特有的基因序列,并通过RNA测序分析菌株V017对伽马辐照的转录组响应及其差异表达基因。【结果】通过从头组装获得菌株V017的完全基因组,其大小为2527399 bp,GC含量为72.9%;比较基因组分析发现菌株V017基因组中存在特有的移动元件序列,可能有助于适应辐照极端环境。转录组分析表明菌株V017在辐照处理后,脂肪酸和色氨酸等基础代谢途径显著下调,而与DNA损伤修复相关的代谢途径则显著上调,其中同源重组修复可能是菌株V017响应辐照的主要途径。【结论】根据藤黄微球菌V017的基因组和转录组分析表明,细胞可能利用特异性的移动元件序列通过DNA重排适应辐照环境,同时通过启动DNA损伤修复和改变一些基础代谢响应辐照胁迫,这可能是菌株V017产生中度辐照抗性特性的重要原因。这些研究为进一步理解耐辐射微生物的适应和抗性机制,以及耐辐射微生物资源的开发利用奠定基础。[Background]Radioresistant microorganisms are important type of extreme microbial resources,which are of great significance for studying radiation-resistance mechanism and environmental protection.[Objective]To analyze the genetic background of Micrococcus luteus V017 and the transcriptome response to radiation through genome and transcriptome.[Methods]The full genome of strain V017 was sequenced and its unique gene sequence was revealed by comparative genome analysis.Further,transcriptome response of strain V017 to gamma ray radiation was performed,and then followed by functional analysis of their differentially expressed genes.[Results]The whole genome of V017 was obtained through de novo assembly.The genome size was 2527399 bp with GC content of 72.9%.Comparative genome analysis revealed many mobile element sequences unique in V017 genome,which may be helpful for it to adapt to the extreme irradiation environment.Transcriptome analysis showed that the basic metabolic pathways such as fatty acid and tryptophan metabolic pathways were significantly down-regulated.By contrary,expression level of the DNA damage repair pathways was significantly up-regulated.Especially,homologous recombination repair may play a major role in response to irradiation.[Conclusion]The genomic and transcriptome data analysis implied that the specific mobile sequences of strain V017 may help to adapt to the radiation environment through modulation of DNA rearrangement.Alternation of DNA damage repair and basic metabolic pathways in response to radiation stress may be an important reason for the moderate radiation resistance of strain V017.These studies laid the foundation for further understanding the adaptation and resistance mechanisms of radioresistant microorganisms,as well as the utilization of its microbial resources.

关 键 词：耐辐射微生物 藤黄微球菌 基因组 转录组 抗性机制 

分 类 号：Q933[生物学—微生物学]