南方根结线虫伴生细菌宏基因组fosmid文库构建及其特征分析

Metagenomic fosmid library construction of Meloidogyne incognita associated bacteria and features analysis

为了研究南方根结线虫与伴生细菌的互作及其伴生细菌多样性，采用碘海醇介质离心技术、SDS裂解法和酚／氯仿抽提法等构建了南方根结线虫Meloidogyne incognita伴生细菌宏基因组fosmid文库，并进行文库特征分析。结果表明，该文库包含3万个克隆，插入片段大小分布在30～45kh之间，平均长度为40kb左右；共计包含1171MbDNA；质粒在fosmid传代中稳定遗传，没有发现插入片段的丢失或重排。末端测序结果显示，文库中南方根结线虫序列占2．04％，细菌序列占44．90％，无同源序列占53．06％；南方根结线虫伴生细菌优势种群为Sphingopyxis属和代尔夫特菌属De圻沉。

In order to study the diversity of Meloidogyne incognita associated bacteria, and analyze the interaction between M. incognita and associated bacteria, a fosmid library of genome of M. incognita associated bacteria has been constructed by the ways of Nycodenz centrifuge, sodium dodecyl sulfate （SDS） lysis and phenol chloroform extracting methods. The results of features analysis indicate that the library consists of 30 000 clones ; the length of insertion element is between 30 - 45 kb, and the average length is about 40kb; the total size of the fosmid library is estimated to 1 171 Mb. The insert DNA was stable dur- ing the propagation in the fosmid system. The results of end-sequencing indicate that the percentage of the M. incognita sequence was 2.04% , the bacterium sequence was 44.90% , the sequences without significant similarity was 53.06% ; Sphingopyxis and Delftia were dominant communities of M. incognita associated bacteria.