REAL-TIME MEASUREMENT OF CELL PERMEABILIZATION WITH LOW-MOLECULAR-WEIGHT MEMBRANOLYTIC AGENTS

A new method for studying the action of membranolytic agents by simple measurement of light emitted from cells is described. It is based on the expression of the click beetle (Pyrophorus plagiophthalamus) lucif erase gene (lucGR) in Escherichia coil, Bacillus subtilis and Spodopte ra frugiperda cells in order to make them bioluminescent. The diffusio n of the substrate for luciferase enzyme through the cell membranes is very slow at physiological pH, and therefore a change in membrane per meability is seen as a change of in-vivo luminescence of cells. The ce lls used in this study represent different membrane structures, and th us allow a comparison of the reactions of the different membranes towa rds membranolytic agents in a real-time measurement. The dose-response data correlated well with target cell viable count. In addition, the time course of light emission as a consequence of permeabilizing compo und is dose-dependent. The action of the compounds on prokaryotic and eukaryotic cells was found to be highly dependent on the permeabilizer used.