title: Hormesis in high-throughput screening of antibacterial compounds in E coli.
abstract: This article assesses the response below a toxicological threshold for 1888 antibacterial agents in Escherichia coli, using 11 concentrations with twofold concentration spacing in a high-throughput study. The data set had important strengths such as low variability in the control (2%-3% SD), a repeat measure of all wells, and a built-in replication. Bacterial growth at concentrations below the toxic threshold is significantly greater than that in the controls, consistent with a hormetic concentration response. These findings, along with analyses of published literature and complementary evaluations of concentration-response model predictions of low-concentration effects in yeast, indicate a lack of support for the broadly and historically accepted threshold model for responses to concentrations below the toxic threshold.
authors.affiliation: Department of Public Health, Environmental Health Sciences, University of Massachusetts, Amherst, MA, USA. edwardc@schoolph.umass.edu
authors.forename: Edward J
authors.initials: EJ
authors.lastname: Calabrese
authors.forename: George R
authors.initials: GR
authors.lastname: Hoffmann
authors.forename: Edward J
authors.initials: EJ
authors.lastname: Stanek
authors.forename: Marc A
authors.initials: MA
authors.lastname: Nascarella
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000592:standards / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D004926:Escherichia coli / Q000187:drug effects*; D020714:Maximum Tolerated Dose; D008826:Microbial Sensitivity Tests; D019055:No-Observed-Adverse-Effect Level
chemical_list: D000900:Anti-Bacterial Agents