题目：The diversity of coral associated bacteria and the environmental factors affect their community variation,

作者: Yan-Ying Zhang, Juan Ling, Qing-Song Yang, You-Shao Wang, Cui-Ci Sun, Hong-Yan Sun, Jing-Bin Feng,Yu-Feng Jiang, Yuan-Zhou Zhang, Mei-Lin Wu, Jun-De Dong*

刊物: Ecotoxicology

刊号: 2015,24(7):1467-1477

摘要: Coral associated bacterial community potentially has functions relating to coral health, nutrition and disease. Culture-free, 16S rRNA based techniques were used to compare the bacterial community of coral tissue, mucus and seawater around coral, and to investigate the relationship between the coral-associated bacterial communities and environmental variables. The diversity of coral associated bacterial communities was very high, and their composition different from seawater. Coral tissue and mucus had a coral associated bacterial community with higher abundances of Gammaproteobacteria. However, bacterial community in seawater had a higher abundance of Cyanobacteria. Different populations were also found in mucus and tissue from the same coral fragment, and the abundant bacterial species associated with coral tissue was very different from those found in coral mucus. The microbial diversity and OTUs of coral tissue were much higher than those of coral mucus. Bacterial communities of corals from more human activities site have higher diversity and evenness; and the structure of bacterial communities were significantly different from the corals collected from other sites. The composition of bacterial communities associated with same coral species varied with season’s changes, geographic differences, and coastal pollution. Unique bacterial groups found in the coral samples from more human activities location were significant positively correlated to chemical oxygen demand. These coral specific bacteria lead to coral disease or adjust to form new function structure for the adaption of different surrounding needs further research.

题目：Spatial variations of bacterial community and its relationship with water chemistry in Sanya Bay,South China Sea as determined by DGGE fingerprinting and multivariate analysis,

作者: Juan Ling, Yanying Zhang, Junde Dong*, Youshao Wang, Jingbing Feng, Hongyan Sun, Weihua Zhou,.

刊物: Ecotoxicology

刊号: 2015,24(7):1486-1497

摘要: Bacteria play important roles in the structure and function of marine food webs by utilizing nutrients and degrading the pollutants, and their distribution are determined by surrounding water chemistry to a certain extent. It is vital to investigate the bacterial community’s structure and identifying the significant factors by controlling the bacterial distribution in the paper. Flow cytometry showed that the total bacterial abundance ranged from 5.27 9 105 to 3.77 9 106 cells/mL. Molecular fingerprinting technique, denaturing gradient gel electrophoresis (DGGE) followed by DNA sequencing has been employed to investigate the bacterial community composition. The results were then interpreted through multivariate statistical analysis and tended to explain its relationship to the environmental factors. A total of 270 bands at 83 different positions were detected in DGGE profiles and 29 distinct DGGE bands were sequenced. The predominant bacteria were related to Phyla Protebacteria species (31 %, nine sequences), Cyanobacteria (37.9 %, eleven sequences) and Actinobacteria (17.2 %, five sequences). Other phylogenetic groups identified including Firmicutes (6.9 %, two sequences), Bacteroidetes (3.5 %, one sequences) and Verrucomicrobia (3.5 %, one sequences). Conical correspondence analysis was used to elucidate the relationships between the bacterial community compositions and environmental factors. The results showed that the spatial variations in the bacterial community composition was significantly related to phosphate (P = 0.002, P\0.01), dissolved organic carbon (P = 0.004, P\0.01), chemical oxygen demand (P = 0.010, P\0.05) and nitrite (P = 0.016, P\0.05). This study revealed the spatial variations of bacterial community and significant environmental factors driving the bacterial composition shift. These results may be valuable for further investigation on the functional microbial structure and expression quantitatively under the polluted environments in the world.

题目：Responses of bacterial communities in Seagrass Enhalus acoroides Sediments to Polycyclic Aromatic Hydrocarbon-induced stress,

作者: Juan Ling, Yu-Feng Jiang, You-Shao Wang*, Jun-De Dong*,Yan-Ying Zhang, Yuan-Zhou Zhang.

刊物: Ecotoxicology

刊号: 2015,24(7):1517-1528

摘要: The seagrass meadows represent one of the highest productive marine ecosystems, and have the great ecological and economic values. Bacteria play important roles in energy flow, nutrient biogeochemical cycle and organic matter turnover in marine ecosystems. The seagrass meadows are experiencing a world-wide decline, and the pollution is one of the main reasons. Polycyclic aromatic hydrocarbons (PAHs) are thought be the most common. Bacterial communities in the seagrass Enhalus acoroides sediments were analyzed for their responses to PAHs induced stress. Dynamics of the composition and abundance of bacterial communities during the incubation period were explored by polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) and quantitative PCR assay, respectively. Both the incubation time and the PAHs concentration played significant roles in determining the microbial diversity, as reflected by the detected DGGE bands. Analysis of sequencing results showed that the Gammaproteobacteria were dominant in the seagrass sediments, accounting for 61.29 % of all sequenced bands. As PAHs could be used as carbon source for microbes, the species and diversity of the PAH-added groups (group 1 and 2) presented higher Shannon Wiener index than the group CK, with the group 1 showing the highest values almost through the same incubation stage. Patterns of changes in abundance of the three groups over the experiment time were quite different. The bacterial abundance of the group CK and group 2 decreased sharply from 4.15 9 1011 and 6.37 9 1011 to 1.17 9 1010 and 1.07 9 1010 copies/g from day 2 to 35, respectively while bacterial abundance of group 1 increased significantly from 1.59 9 1011 copies/g at day 2 to 8.80 3 1011 copies/g at day 7, and then dropped from day 14 till the end of the incubation. Statistical analysis (UMPGA and PCA) results suggested that the bacterial community were more likely to be affected by the incubation time than the concentration of the PAHs. This study provided the important information about dynamics of bacterial community under the PAHs stress and revealed the high bacterial diversity in sediments of E. acoroides. Investigation results also indicated that microbial community structure in the seagrass sediment were sensible to the PAHs induced stress, and may be used as potential indicators for the PAHs contamination.

题目：Cultivation-dependent analysis of the microbial diversity associated with the seagrass meadows in Xincun Bay,South China Sea.

作者: Yufeng Jiang,Juan Ling,Youshao Wang,Biao Chen,Yanying Zhang,Junde Dong*

刊物: Ecotoxicology

刊号: 2015,24(7):1540-1547

摘要: Microbial communities have largely existed in the seagrass meadows. A total of 496 strains of the bacteria in the seagrass meadows, which belonged to 50 genera, were obtained by the plate cultivation method from three sites of Xincun Bay, South China Sea. The results showed that Bacillales and Vibrionales accounted for the highest proportions of organisms in all communities. The diversity of the bacteria in the sediment was higher than that associated with seagrass. Thalassia hemperichii possessed the highest abundance of bacteria, followed by Enhalus acoroides and Cymodocea rotundata. Robust seasonal dynamics in microbial community composition were also observed. It was found that microbial activities were closely tied to the growth stage of the seagrass. The microbial distribution was the lowest in site 3. The abundance of the bacteria was linked to the interactions between bacteria and plants, the condition of plant and even the coastal water quality and the nutrition level in the sediment.

题目：Illumina-based analysis the microbial diversity associated with Thalassia hemprichii in Xincun Bay,South China Sea.

作者: Yufeng Jiang,Juan Ling,Junde Dong*,Biao Chen,Yanying Zhang,Yuanzhou Zhang,Youshao Wang

刊物: Ecotoxicology

刊号: 2015,24(7):1548-1556

摘要: In order to increase our understanding of the microbial diversity associated with seagrass Thalassia hemprichii in Xincun Bay, South China Sea, 16S rRNA gene was identified by highthrough sequencing method. Bacteria associated with seagrass T. hemprichii belonged to 37 phyla, 99 classes. The diversity of bacteria associated with seagrass was similar among the geographically linked coastal locations of Xincun Bay. Proteobacteria was the dominant bacteria and the a-proteobacteria had adapted to the seagrass ecological niche. As well, a-proteobacteria and Pseudomonadales were associated microflora in seagrass meadows, but the interaction between the bacteria and plant is needed to further research. Burkholderiales and Verrucomicrobiae indicated the influence of the bay from anthropogenic activities. Further, Cyanobacteria could imply the difference of the nutrient conditions in the sites. c-proteobacteria, Desulfobacterales and Pirellulales played a role in the cycle of sulfur, organic mineralization and meadow ecosystem, respectively. In addition, the less abundance bacteria species have key functions in the seagrass meadows, but there is lack knowledge of the interaction of the seagrass and less abundance bacteria species. Microbial communities can response to surroundings and play key functions in the biochemical cycle.