Project description:Xiangjiang River (Hunan, China) has been contaminated with heavy metal for several decades by surrounding factories. However, little is known about the influence of a gradient of heavy metal contamination on the diversity, structure of microbial functional gene in sediment. To deeply understand the impact of heavy metal contamination on microbial community, a comprehensive functional gene array (GeoChip 5.0) has been used to study the functional genes structure, composition, diversity and metabolic potential of microbial community from three heavy metal polluted sites of Xiangjiang River.

2016-08-02 | GSE85064 | GEO

Gene Expression changes induced by exposure to field water samples collected at Walker Mine, CA

Project description:Our research goal is to illustrate the potential of gene expression profiling to discriminate between polluted and non-polluted field sites and predict the presence of a specific contaminant. Using a gene expression analysis, we challenged our custom Daphnia magna cDNA microarray to determine the presence of a specific metal toxicant in blinded field samples collected from two copper mines in California. We compared the gene expression profiles from our field samples to previously established expression profiles for Cu, Cd, and Zn. The expression profiles from the Cu containing field samples clustered with the Cu specific gene expression profiles. Many of the previously discovered copper biomarkers were also differentially expressed in the field samples, suggesting that gene expression analysis is capable of producing robust biomarkers of exposure, which can be validated in field studies. In addition, our study revealed that upstream field samples containing undetectable levels of Cu caused the differential expression of only a few genes, lending support for the concept of a No Observed Transcriptional Effect Level (NOTEL). If confirmed by further studies, the NOTEL may play an important role in discriminating polluted and non-polluted sites in future monitoring efforts. Keywords: ecotoxicogenomic exposure study

2008-06-09 | GSE7666 | GEO

Gene Expression changes induced by exposure to field water samples collected at Greenhorn Mine, CA

2008-06-09 | GSE7667 | GEO

Study of microbial functional structure in Xiangjiang River sediment

2016-08-02 | E-GEOD-85064 | biostudies-arrayexpress

Meta-transcriptomic analysis of the response of river biofilms to pharmaceutical products using anonymous DNA microarray

Project description:Low concentrations of pharmaceutical compounds were shown to induce transcriptional responses in isolated microorganisms, which could have consequences on ecosystem dynamics. In order to test if these transcriptional responses could also be observed in complex river microbial communities, biofilm reactors were inoculated with water from two distinct rivers and supplemented with environmentally relevant doses of four pharmaceutical products (erythromycin-ER, gemfibrozil-GM, sulfamethazine-SN and sulfamethoxazole-SL). To follow the expression of functional genes, we constructed a 9,600 features anonymous DNA microarray platform onto which cDNA from the various biofilms was hybridized.

2010-07-06 | GSE20501 | GEO