Transcriptomic Analyses to Unravel Cronobacter sakazakii Resistance Pathways

The proliferation of antibiotic usage has precipitated the emergence of drug-resistant variants of bacteria, thereby augmenting their capacity to withstand pharmaceutical interventions. Among these variants, <i>Cronobacter sakazakii</i> (<i>C. sakazakii</i>), prevalent in powdered infant formula (PIF), poses a grave threat to the well-being of infants. Presently, global contamination by <i>C. sakazakii</i> is being observed. Consequently, research endeavors have been initiated to explore the strain's drug resistance capabilities, alterations in virulence levels, and resistance mechanisms. The primary objective of this study is to investigate the resistance mechanisms and virulence levels of <i>C. sakazakii</i> induced by five distinct antibiotics, while concurrently conducting transcriptomic analyses. Compared to the susceptible strains prior to induction, the drug-resistant strains exhibited differential gene expression, resulting in modifications in the activity of relevant enzymes and biofilm secretion. Transcriptomic studies have shown that the expression of glutathione S-transferase and other genes were significantly upregulated after induction, leading to a notable enhancement in biofilm formation ability, alongside the existence of antibiotic resistance mechanisms associated with efflux pumps, cationic antimicrobial peptides, and biofilm formation pathways. These alterations significantly influence the strain's resistance profile.