Involvement of <i>Escherichia coli-</i> encoded Lon protease and its substrates in phenotypic antibiotic resistance elicited by 4-amino-2-nitrophenol

<i>E. coli</i> is one of the common microorganisms in feces-contaminated sewage and often interacts with several pollutants. This study identifies the roles of Lon protease and its substrate MarA in inducing nitroreductases, NfsA and NfsB, in reducing toxic 2,4-DNP to less toxic 4,2-ANP, a novel inducer of phenotypic antibiotic resistance in <i>E. coli</i>. This study sheds light on the roles of <i>E. coli</i>-encoded Lon protease upon exposure to harmful nitroaromatics. Common environmental pollutants can act as a selective pressure, favoring the survival as well as proliferation of bacteria containing antibiotic-resistant genes, which can easily be transferred to other bacteria through horizontal gene transfer. This study offers insights into mitigation methods in <i>E. coli</i>, a well-characterized model. It is possible that such environmental pollution strategies may be translated to other models, such as <i>Pseudomonas</i>, which are commonly used in bioremediation studies.