USE OF CONTROLLED LUCIFERASE EXPRESSION TO MONITOR CHEMICALS AFFECTING PROTEIN-SYNTHESIS

In this article, we present a new bioluminescent test system for the s creening of chemical compounds with an inhibitory effect on protein sy nthesis. The test is based on the measurement of real-time in vivo lig ht production by Escherichia coli strains expressing different lucifer ase genes. The eukaryotic lucGR gene from Pyrophorus plagiophthalamus was found to be the best of three types of luciferase genes tested. Ch emicals with known inhibitory effects on protein synthesis were used a s test chemicals together with some general toxicants. The incubation of a test chemical with cells was performed either prior to or after t he induction of protein synthesis, and the difference in the results o f the two methods distinguishes the possible influence on protein synt hesis from direct metabolic inhibition. Using lyophilized bacteria, th e test is performed in less than an hour without any bacterial cultiva tion, which makes the test suitable for rapid and sensitive screening of chemicals or environmental samples. Compared with the standardized 50% inhibitory concentration calculation method of the bioluminescent cytotoxicity test, the more direct approach of calculation developed i n this study proved to be more convenient than and as reliable as the standard method.