title: Prokaryotic real-time gene expression profiling for toxicity assessment.
abstract: Examining global effects of toxins on gene expression profiles is proving to be a powerful method for toxicity assessment and for investigating mechanisms of toxicity. This study demonstrated the application of prokaryotic real-time gene expression profiling in Escherichia coli for toxicity assessment of environmental pollutants in water samples, by use of a cell-array library of 93 E. coli K12 strains with transcriptional green fluorescent protein (GFP) fusions covering most known stress response genes. The high-temporal-resolution gene expression data, for the first time, revealed complex and time-dependent transcriptional activities of various stress-associated genes in response to mercury and mitomycin (MMC) exposure and allowed for gene clustering analysis based on temporal response patterns. Compound-specific and distinctive gene expression profiles were obtained for MMC and mercury at different concentrations. MMC (genotoxin) induced not only the SOS response, which regulates DNA damage and repair, but also many other stress genes associated with drug resistance/sensitivity and chemical detoxification. A number of genes belonging to the P-type ATPase family and the MerR family were identified to be related to mercury resistance, among which zntA was found to be up-regulated at an increasing level as the mercury concentration increased. A mechanism-based evaluation of toxins based on real-time gene expression profiles promises, to be an efficient and informative method for toxicity assessment in environmental samples.
authors: Department of Civil and Environmental Engineering, Northeastern University, Boston, Massachusetts 02115, USA.
authors: Annalisa
authors: A
authors: Onnis-Hayden
authors: Haifeng
authors: H
authors: Weng
authors: Miao
authors: M
authors: He
authors: Sonja
authors: S
authors: Hansen
authors: Valentin
authors: V
authors: Ilyin
authors: Kim
authors: K
authors: Lewis
authors: April Z
authors: AZ
authors: Guc
mesh_terms: D000903:Antibiotics, Antineoplastic / Q000633:toxicity; D004305:Dose-Response Relationship, Drug; D004784:Environmental Monitoring; D004785:Environmental Pollutants / Q000633:toxicity; D048168:Escherichia coli K12 / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology*; D008628:Mercury / Q000633:toxicity*; D016685:Mitomycin / Q000633:toxicity*; D012680:Sensitivity and Specificity
chemical_list: D000903:Antibiotics, Antineoplastic; D004785:Environmental Pollutants; D029968:Escherichia coli Proteins; D016685:Mitomycin; D008628:Mercury