Project description:To further explore the biotoxicity mechanisms of CeO2 nanoparticles (NPs) and the recovery strategies of the according impaired Nitrosomonas europaea (N. europaea, ATCC 19718) cells, a genome-sequenced model ammonia oxidizing bacterium (AOB) commonly detected in the activated sludge of biological wastewater treatment plants, the whole-genome microarray analysis was applied to retrieve the induced transcriptional responses, after their physiological and metabolic activities were evealed.
Project description:To further explore the biotoxicity mechanisms of zinc oxide nanoparticles (ZnO NPs) and the recovery strategies of the accordingly impaired Nitrosomonas europaea (N. europaea, ATCC 19718) cells, a genome-sequenced model ammonia-oxidizing bacterium (AOB) commonly detected in the activated sludge of biological wastewater treatment plants, whole-genome microarray analysis was applied to retrieve the induced transcriptional responses, after their physiological and metabolic activities were revealed.
Project description:To further explore the biotoxicity mechanisms of TiO2 nanoparticles (NPs) and the recovery potentials of the impaired Nitrosomonas europaea (N. europaea, ATCC 19718) cells, a genome-sequenced model ammonia oxidizing bacterium (AOB) commonly detected in the activated sludge of biological wastewater treatment plants, the whole-genome microarray analysis was applied to retrieve the induced transcriptional responses during the long-term exposure, after the toxicity effects and the recovery potentials were assessed at both physiological and metabolic levels.
Project description:To further explore the biotoxicity mechanisms of zinc oxide nanoparticles (ZnO NPs) and the recovery strategies of the accordingly impaired Nitrosomonas europaea (N. europaea, ATCC 19718) cells, a genome-sequenced model ammonia-oxidizing bacterium (AOB) commonly detected in the activated sludge of biological wastewater treatment plants, whole-genome microarray analysis was applied to retrieve the induced transcriptional responses, after their physiological and metabolic activities were revealed. The whole-genome expressions were measured after exposure to 50 ppm ZnO NPs and 12-hrs recovery incubation when the ammonia removal rate (ARA) declined by 10% in the chemostat bioreactor. Three independent experiments were performed for each experiment.
Project description:Pure cultures of ammonia oxidizing bacterium, Nitrosomonas europaea, are exposed to cyanide in pseudo-steady state batch reactor in presence of ammonia. Nitrosomonas europaea are generally regarded as the most sensitive organism to various inhibitors commonly encountered in the wastewater treatment plants (WWTP). To find stress genes of Nitrosomonas europaea to cyanide known as inhibitor of respiratory process, whole-genome transcript response to cyanide was determined in this research using microarray and qRT-PCR. When 1 uM NaCN inhibits nitrification about 50 %, transcript levels of 35 genes were increased while transcript levels of 29 genes were decreased, showing more than 2-fold in total 2460 genes. moeZ (NE2353), homologue with rhodanases related to detoxification of CN-, showed 7-fold up regulation and gene cluster including moeZ also showed significant up regulation. Keywords: cyanide, stress response, moeZ
Project description:To further explore and differentiate the biotoxicity mechanisms of individual nanoparticles (NPs) and NP mixture on Nitrosomonas europaea (N. europaea, ATCC 19718) at genetic level, a genome-sequenced model ammonia oxidizing bacterium (AOB) commonly detected in the activated sludge of biological wastewater treatment plants, the induced whole-genome expressions were analyzed with the high throughput Microarray technique, after the dose-dependent changes of N. europaea’s physiological, metabolic and AMO enzyme activities in single and dual component NP systems was evaluated.
Project description:Pure cultures of ammonia oxidizing bacterium, Nitrosomonas europaea, are exposed to cyanide in pseudo-steady state batch reactor in presence of ammonia. Nitrosomonas europaea are generally regarded as the most sensitive organism to various inhibitors commonly encountered in the wastewater treatment plants (WWTP). To find stress genes of Nitrosomonas europaea to cyanide known as inhibitor of respiratory process, whole-genome transcript response to cyanide was determined in this research using microarray and qRT-PCR. When 1 uM NaCN inhibits nitrification about 50 %, transcript levels of 35 genes were increased while transcript levels of 29 genes were decreased, showing more than 2-fold in total 2460 genes. moeZ (NE2353), homologue with rhodanases related to detoxification of CN-, showed 7-fold up regulation and gene cluster including moeZ also showed significant up regulation. Keywords: cyanide, stress response, moeZ The 1 uM NaCN caused more than 50 % inhibition in physiological response for 1 hour incubation. Transcriptional levels of the cells inhibited by cyanide were compared with the cells under control condition.
Project description:To further explore and differentiate the biotoxicity mechanisms of individual nanoparticles (NPs) and NP mixture on Nitrosomonas europaea (N. europaea, ATCC 19718) at genetic level, a genome-sequenced model ammonia oxidizing bacterium (AOB) commonly detected in the activated sludge of biological wastewater treatment plants, the induced whole-genome expressions were analyzed with the high throughput Microarray technique, after the dose-dependent changes of N. europaea’s physiological, metabolic and AMO enzyme activities in single and dual component NP systems was evaluated. NP stress induced gene expressions were measured after 6hr exposure to 10 ppm nano-ZnO, 50 nano-TiO2 and their mixture.Three independent experiments were performed for each experiment.