香樟产芽孢内生细菌的系统发育多样性

Phylogenetic Diversity of Spore-forming Endophytic Bacteria Isolated from Cinnamomum camphora (Linn.) Presl

摘要:

为了解香樟产芽孢内生细菌的多样性, 采用改良的NA培养基分离、去除冗余及芽孢染色, 得到40株产芽孢内生细菌, 占分离所得内生细菌总数的29.9%, 其中根、茎、叶中分别分离到25、5和10株。16S rRNA序列系统发育分析结果表明, 这40株菌分属于Bacillus、Lysinibacillus、Paenibacillus和Brevibacillus属的12个种; 7株菌的16S rRNA部分序列与数据库中模式菌株对应序列相似性小于97%, 代表着潜在新类群的存在。同时, 3个部位分离出的产芽孢内生细菌既呈现出一定程度的细菌区系相似性, 又表现出细菌区系的器官特异性。

Abstract:

Improved NA medium was used to study the diversity of endophytic spore-forming bacteria of Cinnamomum camphora (Linn.) Presl. After spore staining and removing of the redundant isolates, 40 non-redundant spore-forming bacterial isolates were ascertained, which accounted for 29.9% of all the endophytic bacterial isolates, and 25 strains of the 40 were from roots, 5 strains from stems, 10 strains from leaves. Phylogenetic analysis based on 16S rRNA sequences showed that the 40 strains attributed to 12 species of the genera Bacillus, Lysinibacillus, Paenibacillus and Brevibacillus; 7 strains with under 97% sequence similarities respectively to their closely related member were presumed to be potential novel species. Furthermore, microflora of endophytic spore-forming bacteria in roots, stems and leaves of C. camphora showed that some bacteria distributed in different organs, others were organ-specific.