Dai J X, Liu X M, Wang Y J
Key Laboratory of the Ministry of Education for the Conservation and Utilization of Special Biological Resources of Western China, Ningxia University, Yinchuan, Ningxia, China.
Key Laboratory of the Ministry of Education for the Conservation and Utilization of Special Biological Resources of Western China, Ningxia University, Yinchuan, Ningxia, China
Genet Mol Res. 2014 Apr 3;13(2):2349-58. doi: 10.4238/2014.April.3.7.
The diversity of endophytic bacteria in the sand-fixation plant Caragana microphylla was investigated by amplified rDNA restriction analysis and by sequence and phylogenetic comparisons of the 16S rRNA genes. A total of 24, 19, and 17 operational taxonomic units were identified from 16S rDNA libraries of the plant roots, stems and leaves, respectively. Homology analysis revealed a 92-100% identity of bacterial 16S rDNA sequences compared with those in the GenBank database. The bacteria identified by sequence homology fell into the following groups: α-Proteobacteria, β-Proteobacteria, γ-Proteobacteria, bacilli, and uncultured bacterium. Sequence analysis demonstrated that the roots were colonized predominantly by Bradyrhizobiaceae, while bacteria from Burkholderiaceae and Sphingomonadaceae were predominant in the stems and leaves, respectively. Additionally, the endophytic bacterial community in leaves was more diverse than those in the roots and stems. Overall, the most abundant bacteria in all three tissues analyzed were from the Sphingomonadaceae and Burkholderiaceae families, although many bacterial populations were found in only a single tissue. These results suggest that the bacterial population of C. microphylla is diverse.
通过扩增核糖体DNA限制性分析以及16S rRNA基因的序列和系统发育比较，对固沙植物小叶锦鸡儿内生细菌的多样性进行了研究。分别从植物根、茎和叶的16S rDNA文库中鉴定出总共24个、19个和17个操作分类单元。同源性分析表明，与GenBank数据库中的序列相比，细菌16S rDNA序列的同一性为92%-100%。通过序列同源性鉴定出的细菌分为以下几类：α-变形菌纲、β-变形菌纲、γ-变形菌纲、芽孢杆菌以及未培养细菌。序列分析表明，根中主要定殖有慢生根瘤菌科细菌，而伯克霍尔德氏菌科和鞘氨醇单胞菌科细菌分别在茎和叶中占主导地位。此外，叶中的内生细菌群落比根和茎中的更具多样性。总体而言，在所有分析的三个组织中，最丰富的细菌来自鞘氨醇单胞菌科和伯克霍尔德氏菌科，尽管许多细菌种群仅在单一组织中被发现。这些结果表明小叶锦鸡儿的细菌种群具有多样性。
