摘要
为了解烟草根部内生细菌多样性,采用改进的CTAB法提取烟草根部总DNA,利用细菌16 S rDNA基因通用引物对烟草根总DNA进行16 S rDNA扩增,构建烟草根部内生细菌16 S rDNA克隆文库;挑取具有不同酶切谱型的克隆进行测序、比对并构建16 S rDNA基因系统发育树。构建的烟草根部内生细菌16 S rDNA克隆文库中,155个克隆分属于36个不同的分类单元,Blast结果表明,大部分克隆与已知细菌的16 S rDNA序列相似性较高,分别属于变形菌门(Proteobacteria)的Alpha、Gamma、Beta亚群,放线菌门(Actinobacteria),拟杆菌门(Bacteroidetes),厚壁菌门(Fir-micutes)中的肠杆菌属(Enterobacter)、不动杆菌属(Acinetobacter)、寡养食单胞菌属(Stenotrophomonas)、假单胞菌属(Pseudomonas)、嗜甲基菌属(Methylobacillus)、食酸菌属(Acidovorax)、芽孢杆菌属(Bacillus)等16个属,其中13.5%的克隆序列与非可培养细菌(Uncultured bacteria)的相似性在93%～99%之间,假单胞菌属细菌是烟草根部内生细菌的优势种群。这些研究结果说明烟草根部存在较为丰富的内生细菌系统发育多样性,并且潜藏着未知的内生细菌资源。
To the aim of study was to investigate endophytic bacterial diversity in tobacco root,to lay a founda- tion for furthering to tap. We investigated endophytic bacterial diversity in tobacco root from Yunnan by culture-in- dependent method. Total DNA genome of tobacco root sample was extracted using CTAB procedure with some modi-fications. A pair of bacterial PCR primers was used for endophytic bacterial 16 S rDNA amplification and a clone li- brary was constructed for the tobacco root DNA samples. Clones screened from clone library on the basis of Msp I digestion patterns were sequenced and compared, flowed by constructing Neighbor-Joining tree. The results show thatin total 155 clones were grouped to 36 operational taxonomic units, most of the clones showed high similarity to the known cultured bacteria. Sequence analysis revealed diverse phyla of bacteria in the 16 S rDNA library,which con- sisted of alpha, gamma, Beta subclasses of the Proteobacteria, Actinobacteria, Bacteroides, Firmicutes and Uncul-tured bacteria;86.2% of the clones were highly related to the known bacteria in the genus Enterobacter,Acinetobact- er, Stenotrophomonas, Pseudomonas, Methylobacillus, Acidovorax, Bacillus etc ; whereas 13.5 % of the clones showed higher affiliation with uncultured bacteria（93% -99% sequence similarity） and may represent novel taxa. Thedominant bacterial groups of tobacco endophytic bacteria belong to Pseudomonas genera. There was abundant endo- phytic bacterial diversity in tobacco root from -Yunnan, and there were large number of unknown endophytic bacterial groups here.
出处
《华北农学报》
CSCD
北大核心
2012年第1期201-209,共9页
Acta Agriculturae Boreali-Sinica
基金
国家自然科学基金资助项目(30860017)
关键词
:非培养方法
内生细菌
烟草
微生物多样性
Culture-independent
Endophytic bacterial
Tobacco
Diversity of microorganism
