The Effect of Reactive Oxygen Species (ROS) in Acidic Resistance Response of Serratia marcescens

Abstract

With the rising cases of Serratia marcescens infections and the emergence of antibiotic-resistant strains, the treatment for patients is more and more challenging. As a result, new pathways for slowing their growth are continuously studied, with one potential structure being the use of reactive oxygen species (ROS), an unstable and highly reactive group of structures. ROS are naturally produced in the cell in moderate amounts, however, when their concentrations are high it creates an oxidative stress condition to the cell, ultimately damaging their cell growth. This research observes the effect of ROS through the addition of Menadione (MD) to synthetically induce oxidative stress in S. marcescens strain taken from local hospitals across Taiwan. The effects of ROS were specifically observed in the expression of the acidic resistance gene (Asr) which is suspected to play a role in the survival mechanism of harsh growth environment. The methods that were used included cloning strategy, PCR, qRT-PCR, C230 assay, and RNA sequencing. The finding suggests that the decrease in Asr gene expression might indicate a survival mechanism of S. marcescens upon an oxidative stress condition.