NO impact on E. coli, P. mirabilis, and E. faecalis strains isolated after NO pulses. Gram-negative enteric bacterial populations were isolated following 10 μM and 100 μM NO administered in 3 pulses on FM2 microbiota, enumerated (A), and identified (B) on MacConkey selective medium. Their corresponding abundance was measured by 16S rDNA sequencing (C). The isolated strains were then subjected to in vitro NO stress at various concentrations (0 to 1,000 μM), and survival was assessed by plating on selective media (D).