Quantitative evaluation of DNA damage caused by atmospheric and room-temperature plasma (ARTP) and other mutagenesis methods using a rapid umu-microplate test protocol for microbial mutation breeding

Abstract

• Mutation breeding is an important technique used in the improvement of strain traits in fermentation industry. • However, the evaluation of the effects after different mutagenic treatment lacks quantification strategies. • Here we developed the umu -microplate test providing a feasible method for a quick quantitative evaluation of DNA damage caused by different mutagenic treatments in the study of the microbial mutation breeding. Mutagenesis is an important technique for microbial mutation breeding. As the source of mutations, DNA damage extent is a key indicator for the effectiveness of mutagenesis. Therefore, a rapid and easy DNA damage quantification method is required for the comparison of mutagenesis effects and development of mutagenesis tools. Here, we used the umu -microplate test system to quantitatively compare the DNA damage strength caused by atmospheric and room-temperature plasma (ARTP) and other traditional mutagenesis methods including: ultraviolet radiation (UV), diethyl sulfate (DES) and 4-nitroquinoline-1-oxide (4-NQO). The test strain of Salmonella typhimurium TA1535/pSK1002 was used to monitor the time-course profile of β-galactosidase activity induced by DNA damage caused by different mutagenesis methods using a microplate reader. The umu -microplate test results showed that ARTP caused higher extent of DNA damage than UV and chemical mutagens, which agrees well with the result obtained by SOS-FACS-based quantification method as reported previously. This umu -microplate test is accessible for broad researchers who are lack of the expensive FACS instruments and allows the quick quantitative evaluation of DNA damage among living cells for different mutagenesis methods in the study of the microbial mutation breeding.