博士 / 國立中興大學 / 生物科技學研究所 / 104 / Microbial endoliths, which inhabit interior pores of rocks, skeletons and coral, are ubiquitous in terrestrial and marine environments. In the present study, various colored layers stratified the endolithic environment within the skeleton of Isopora palifera; however, there was usually a distinct green-pigmented layer in the skeleton beneath the living coral tissue. To characterize diversity of endolithic microorganisms, 16S ribosomal RNA gene amplicon pyrosequencing was used to investigate bacterial communities in the green layer of I. palifera coral colonies retrieved from different locations (Kenting, Kunguan, and Chaikou) and various depths at Kunguan. The result showed that the dominant bacteria in the green layer belonged to the bacterial phylum Chlorobi, green sulfur bacteria capable of anoxygenic photosynthesis and nitrogen fixation. In addition, the variance of endolithic bacterial community within the green layer was subjected to the difference of location but not depth. Specifically, genus Prosthecochloris were prevalent in this green layer in the most coral colonies regardless of the difference of location and depth, suggesting versatile abilities in Prosthecochloris to accommodate different conditions. Moreover, using a metagenomics approach, nitrogen cycling of the endolithic bacteria within the green layer was displayed, indicating the green sulfur bacteria is essential in nitrogen fixation and assimilation. To our knowledge, this is the first study to provide a detailed profile of endolithic bacteria in coral skeleton, as well as, to determine their potential functions in nitrogen metabolism in this habitat. Based on our findings, we infer that these bacteria may have an important functional role in the coral holobiont in the nutrient-limited coral reef ecosystem.
| Identifer | oai:union.ndltd.org:TW/104NCHU5111021 |
| Date | January 2016 |
| Creators | Shan-Hua Yang, 楊姍樺 |
| Contributors | Sen-Lin Tang, 湯森林 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | en_US |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 123 |
Page generated in 0.0052 seconds