基于基因组De novo测序的离子束重组沙漠寡营养细菌的16S rRNA基因研究

Study on 16S rRNA Gene of Desert Oligotrophic Bacteria Recombined by Ion Beam Based on De novo Sequencing

为了进一步理解低能N+注入在沙漠寡营养细菌(DOB)系统发育与进化中的作用,本研究基于DOB基因组De novo测序数据,应用生物信息学方法对3株离子束重组菌株DOB073、DOB113和DOB981的16S r RNA基因的突变与进化进行了分析。分析表明,3株离子束重组DOB的16S r RNA基因拷贝数均比原始菌株增加了5个,并分别在C1区、V1区、V2区、V4区、V6区、V7区和V9区发生了碱基突变。进化分析显示DOB981的进化速度快于DOB073和DOB113。16S r RNA的保守二级结构预测表明,9个保守二级结构所处碱基位置分别为:80~120、120~240、240~360、360~480、400~520、640~760、760~880、800~920和1 420~1 540。本研究为低能离子注入介导的原核微生物进化提供了直接的分子证据。

In order to further understand the role of low energy N^＋ implantation in the system development and evolution of desert oligotrophic bacteria （DOB）, the mutation and evolution of 16S rRNA genes of three ion beam reecombinant strains DOB073, DOB 113 and DOB981 were analyzed based on DOB genome by De novo sequencing data and bioinformatics methods in this study. The results showed that the 16S rRNA gene copy numbers of three ion beam recombinant DOB were five more than the wildtype strain, and there were base mutation occurred in the regions of C1, V1, V2, V4, V6, V7 and V9. Evolutionary analysis showed that the evolution speed of DOB981 was faster than that of DOB073 and DOB113. The prediction of conserved secondary structure of 16S rRNA showed that the base positions of nine conserved secondary structures were： 80-120, 120-240, 240-360, 360-480, 400-520, 640-760, 760-880, 800-920 and 1 420-1 540. This study provided a direct molecular evidence for the evolution ofprokaryotic microorganisms that mediated by low energy ion implantation.