Comparison of Escherichia coli Responses to Different Silver Nanoparticles with Different Particle Sizes and Surface Coatings

AgNPs are widely used for their excellent antimicrobial properties, whereas the cytotoxicity they possess makes them an unignorable environmental problem. Considering the impact of particle size and surface coating on the antibacterial properties, four types of AgNPs are selected: citrate-coated 20 nm (C20), polyvinylpyrrolidone-coated 20 nm (P20), citrate-coated 100 nm (C100), and polyvinylpyrrolidone-coated 100 nm (P100) AgNPs. All four AgNPs significantly affect the ribosome pathway, with stronger binding of large and small subunits. 20 nm and 100 nm AgNPs both affected the biosynthesis and metabolism of several amino acids (including arginine, glycine, serine, threonine, glyoxylic acid, and dicarboxylic acid). P20 and C100 exposure affected bacterial chemotaxis and flagellar motility. This study preliminarily explained the response mechanism of E. coli to AgNPs with different properties, which provided a theoretical basis for predicting the response mechanism of E. coli to metal nanoparticles with similar properties. Toxic effects of four different types of AgNPs on Escherichia coli. image