ABSTRACT
The microbiota in solar salterns plays an important role in salt production quantitatively and qualitatively. Bohai Bay coast is the major sea salt producing area in China. However, few ecological characterization studies of the Bohai Bay salt ponds, particularly of their microbial diversity, have been conducted. This study investigated the structure and diversity of the bacterial community in Hangu saltworks in response to environmental factors. The brine water was sampled from five selected saltponds within a salinity range of 5.0-19.3% in May, July, and October, 2012. Phylogenetic analysis based on the denaturing gradient gel electrophoresis (DGGE) patterns of the PCR-amplified 16S rRNA gene fragment showed that, rather than pond salinity, especially the month of sampling influenced the structure of the bacterial community in the saltponds, which may be related to the water temperature or other factors fluctuating over the months. Moreover, canonical correspondence analysis of biological and physico-chemical parameters indicated that especially other environmental factors such as nitrogenous and phosphorous nutrient contents and pH structured the microbial community. The relatively high range-weighted richness index and Shannon-Wiener index (H') observed in this study reflect the high level of richness and biodiversity present, though there were substantial fluctuations over the months and salinities of sampling. The fragment of 16S rRNA gene sequence recovered from DGGE bands indicated that the bacterial assemblage in Hangu Saltworks was dominated by members of γ-Proteobacteria (34% of total sequences obtained), followed by Firmicutes (14%) and Bacteroidetes (9%).
Subject(s)
Bacteria/classification , Bacteria/isolation & purification , Biota , Salinity , Seawater/microbiology , Bacteria/genetics , China , Cluster Analysis , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Denaturing Gradient Gel Electrophoresis , Nitrogen Compounds/analysis , Phosphates/analysis , Phylogeny , Polymerase Chain Reaction , RNA, Ribosomal, 16S/genetics , Seasons , Seawater/chemistry , Sequence Analysis, DNAABSTRACT
The effects of illumination on growth of Anabaena sp. IB02 and hTNF-alpha expression were studied. Photosynthetic activity, PS I and PS II activity of Anabaena sp. IB02 were assayed. Illumination enhanced the growth of Anabaena sp. IB02 and hTNF-a expression. Some relations were observed between hTNF-alpha expression and ture photosynthesis activity, PS I, PS II activity of Anabaena sp. IB02. Significant differences of the photosynthetic activity of host were detected simultaneously when hTNF-a expressed: the respiration rate increased (-68%), the light saturation point descended (+66%), all these suggested that the metabolic charge of host were increased and grow faster than wild type under low illumination.
