Prescreening of Natural Products in Drug Discovery Using Recombinant Bioluminescent Bacteria

Abstract

Strains of recombinant bioluminescent bacteria (RBB) which respond to toxic environments using various stress promoters are practical means of assessing toxicity. In previous research, RBB has proven useful for highthroughput screening in the drug development process. The goal of this research is to demonstrate that RBB can also be used for the toxicity screening of natural products. The RBB strains used were DPD2511, BBTSbmC, TV1061, and GC2, which were selected to respond to oxidative stress, DNA damage, protein damage, and cellular toxicity, respectively. The test drugs (paclitaxel, etoposide, and pentostatin) were carefully selected because these drugs needed to be natural products or their derivatives whose cellular toxicity had previously been reported from human cell line assays. After treating the RBB strains with various doses of the chosen drugs, their bioluminescent signals were measured over time. The effectiveness of the RBB method was proven by comparing its results to existing toxicity data for the selected drugs. In addition, a similar test using podophyllotoxin, a precursor of etoposide, and a derivative of podophyllotoxin, teniposide, was conducted to prove that the RBB method is suitable for a comparative analysis of toxicity among chemicals with similar molecular structures. As a detection method, RBB bacteria provide a much easier and more rapid culturing process compared to conventional human cell line assays. Because the implementation of the RBB method in the drug discovery process would enable efficient prescreening, a significant reduction in time, effort, and development costs are expected.