Genomic Analysis of Phylotype I Strain EP1 Reveals Substantial Divergence from Other Strains in the Ralstonia solanacearum Species Complex.
Genomic Analysis of Phylotype I Strain EP1 Reveals Substantial Divergence from Other Strains in the Ralstonia solanacearum Species Complex.
复制标题
系统型I菌株EP1的基因组分析揭示了与Ralstonia solanacearum物种复合物中其他菌株的显着差异。
DOI：
10.3389/fmicb.2016.01719
复制
发表时间：
2016
影响因子：
5.2
通讯作者：
Zhang L
中科院分区：
文献类型：
--
作者：
Li P;Wang D;Yan J;Zhou J;Deng Y;Jiang Z;Cao B;He Z;Zhang L
青枯雷尔氏菌复合体是一类具有广泛寄主范围和广泛地理分布的植物病原菌。R.青枯菌分离物可能在包括寄主范围和致病性在内的各种特性上存在很大差异，但潜在的遗传基础仍然模糊不清。本研究对分离自中国广东省的一株对多种茄科作物具有高致病力的致病性菌株EP1进行了全基因组测序。其全基因组含有一条3.95 Mb的染色体和一个2.05 Mb的巨型质粒，比已报道的其它R.青枯菌菌株染色体和大质粒都含有必需的管家基因和许多毒力基因。与其它3株Ⅰ型和3株Ⅱ、Ⅲ、Ⅳ型毒株的比较分析表明，EP 1株存在大量的基因组重排、插入和缺失。基因组序列在4株Ⅰ型菌株中相对保守，但在不同Ⅰ型菌株中差异较大。此外，菌株在其关键毒力基因中表现出相当大的变化，包括编码分泌系统和III型效应子的基因。本研究结果为进一步阐明该菌多样性的遗传基础和寄主范围提供了有价值的信息。青枯菌属
Ralstonia solanacearum species complex is a devastating group of phytopathogens with an unusually wide host range and broad geographical distribution. R. solanacearum isolates may differ considerably in various properties including host range and pathogenicity, but the underlying genetic bases remain vague. Here, we conducted the genome sequencing of strain EP1 isolated from Guangdong Province of China, which belongs to phylotype I and is highly virulent to a range of solanaceous crops. Its complete genome contains a 3.95-Mb chromosome and a 2.05-Mb mega-plasmid, which is considerably bigger than reported genomes of other R. solanacearum strains. Both the chromosome and the mega-plasmid have essential house-keeping genes and many virulence genes. Comparative analysis of strain EP1 with other 3 phylotype I and 3 phylotype II, III, IV strains unveiled substantial genome rearrangements, insertions and deletions. Genome sequences are relatively conserved among the 4 phylotype I strains, but more divergent among strains of different phylotypes. Moreover, the strains exhibited considerable variations in their key virulence genes, including those encoding secretion systems and type III effectors. Our results provide valuable information for further elucidation of the genetic basis of diversified virulences and host range of R. solanacearum species.