Project description:Hepatic transcriptional profiling of fish exposed to sewage to evaluate temporal and concentration trends. Two experiments (Year 1 and 2), each with 6 concentrations (0%, 0.05%, 0.1%, 0.7%, 2% and 5/10%) of sewage diluted in seawater at 4 timepoints (1, 4, 8 and 16 days).
Project description:Effluents from sewage treatment plants contain a mixture of micropollutants with the potential of harming aquatic organisms. Thus, addition of advanced treatment techniques to complement existing conventional methods has been proposed. Some of the advanced techniques could, however, potentially produce additional compounds affecting exposed organisms by unknown modes of action. In the present study the aim was to improve our understanding of how exposure to different sewage effluents affects fish. This was achieved by explorative microarray and quantitative PCR analyses of hepatic gene expression, as well as relative organ sizes of rainbow trout exposed to different sewage effluents (conventionally treated, granular activated carbon, ozonation (5 or 15 mg/L), 5 mg/L ozone plus a moving bed biofilm reactor, or UV-light treatment in combination with hydrogen peroxide). Exposure to the conventionally treated effluent caused a significant increase in liver and heart somatic indexes, an effect removed by all other treatments. Genes connected to xenobiotic metabolism, including cytochrome p450 1A, were differentially expressed in the fish exposed to the conventionally treated effluents, though only effluent treatment with granular activated carbon or ozone at 15 mg/L completely removed this response. The mRNA expression of heat shock protein 70 kDa was induced in all three groups exposed to ozone-treated effluents, suggesting some form of added stress in these fish. The induction of estrogen-responsive genes in the fish exposed to the conventionally treated effluent was effectively reduced by all investigated advanced treatment technologies, although the moving bed biofilm reactor was least efficient. Taken together, granular activated carbon showed the highest potential of reducing responses in fish induced by exposure to sewage effluents.
2012-05-10 | GSE37574 | GEO
Project description:Dynamic effects of sewage sludge treatment on soil microbial community composition, mobilome and resistome
Project description:Surfing motility is a novel form of surface adaptation exhibited by the nosocomial pathogen, Pseudomonas aeruginosa, in the presence of the glycoprotein mucin that is found in high abundance at mucosal surfaces especially the lungs of cystic fibrosis and bronchiectasis patients. Here we investigated the adaptive antibiotic resistance of P. aeruginosa under conditions in which surfing occurs compared to cells undergoing swimming. P. aeruginosa surfing cells were significantly more resistant to several classes of antibiotics including aminoglycosides, carbapenems, polymyxins, and fluroquinolones. This was confirmed by incorporation of antibiotics into growth medium, which revealed a concentration-dependent inhibition of surfing motility that occurred at concentrations much higher than those needed to inhibit swimming. To investigate the basis of resistance, RNA-Seq was performed and revealed that surfing influenced the expression of numerous genes. Included amongst genes dysregulated under surfing conditions were multiple genes from the Pseudomonas resistome, which are known to affect antibiotic resistance when mutated. Screening transposon mutants in these surfing-dysregulated resistome genes revealed that several of these mutants exhibited changes in susceptibility to one or more antibiotics under surfing conditions, consistent with a contribution to the observed adaptive resistance. In particular, several mutants in resistome genes, including armR, recG, atpB, clpS, nuoB, and certain hypothetical genes such as PA5130, PA3576 and PA4292, showed contributions to broad-spectrum resistance under surfing conditions and could be complemented by their respective cloned genes. Therefore, we propose that surfing adaption led to extensive multidrug adaptive resistance as a result of the collective dysregulation of diverse genes.
Project description:Hornyhead turbot (Pleuronichthys verticalis) captured near sewage outfalls are used as sentinel fish for monitoring exposure to industrial and agricultural chemicals of ~20 million people living in coastal southern California. Although analyses of hormones in blood and organ morphology and histology in fish are useful for assessing exposure, there is a need for quantitative and sensitive molecular measurements, as many contaminants produce subtle effects. A novel multispecies microarray and qRT-PCR were used to investigate endocrine disruption in turbot captured near sewage outfalls in San Diego, Orange County and Los Angeles California. Analysis of expression of genes involved in hormone [e.g. estrogen, androgen, thyroid] responses and xenobiotic metabolism in turbot livers was correlated with phenotypic end points.
Project description:Metagenomic analysis reveals differential effects of sewage treatment on the microbiome and antibiotic resistome in Bengaluru, India