| Summary: | 碩士 === 國立成功大學 === 生命科學系碩博士班 === 96 === Bioremediation is the most concern technology of environmental remediation in recent year. Analysis of microbial community is indispensable to understand mechanism of bioremediation. The soil samples of this study were from petroleum-contaminated sites, including LY, YK, FD, KS, and KT. We used traditional culture and molecular biology methods to investigate the microbial communities of these sites. In 16S rRNA gene clone libraries of each site, large diversity was found between these microbial communities. Microbes at each site had specific locus in phylogenetic tree of 16S rRNA gene clone libraries. Interestingly, β-proteobacteria could be divided five groups by these five sites. LY site is contaminated longer time. As we known, it had different microbial community from others and most of the microbes here was uncultured α-, β-, and γ-proteobacteria. Meanwhile, most of the microbes in YK was Burlkhoderia. In 16S rRNA gene clone libraries of petroleum-contaminated sites, there were 21 OTUs (operational taxonomic units) related to degradation of petroleum, and YK site had a large fraction of Pseudomonas and Burlkhoderia, 28.0% and 24.5% respectively. This study used T-RFLP to monitor the change of microbial community at KS (more diesel oil) and KT (more heavy oil) sites during bioremediation, and used NMS (nonmetric multidimensional scaling) to analyze the similarity of microbial community. As the result, similarity between the two sites was small in 0 day. It may be caused by the different component of petroleum at two sites. As for the dissimilarity at different time, it suggests that microbial community change obviously in bioremediation.
This study also found that one-stage PCR amplification produced bias of bacterial ratio between templates and products, and the bias increased if there was a mismatch site between primers and templates. Two-stage PCR amplification could diminish the bias. Therefore, in T-RFLP, this method could ameliorate the bias caused by mismatch between primers and templates.
|
|---|
