The stationary phase-specific sRNA FimR2 is a multifunctional regulator of bacterial motility, biofilm formation and virulence

Abstract

Bacterial pathogens employ a plethora of virulence factors for host invasion, and their use is tightly regulated to maximize infection efficiency and manage resources in a nutrient-limited environment. Here we show that during Escherichia coli stationary phase the 3′ UTR-derived small non-coding RNA FimR2 regulates fimbrial and flagellar biosynthesis at the post-transcriptional level, leading to biofilm formation as the dominant mode of survival under conditions of nutrient depletion. FimR2 interacts with the translational regulator CsrA, antagonizing its functions and firmly tightening control over motility and biofilm formation. Generated through RNase E cleavage, FimR2 regulates stationary phase biology by fine-tuning target mRNA levels independently of the chaperones Hfq and ProQ. The Salmonella enterica orthologue of FimR2 induces effector protein secretion by the type III secretion system and stimulates infection, thus linking the sRNA to virulence. This work reveals the importance of bacterial sRNAs in modulating various aspects of bacterial physiology including stationary phase and virulence.

Antibacterial and Biofilm Production Inhibition Activity of Thymus vulgaris L. Essential Oil against Salmonella spp. Isolates from Reptiles

“…The inoculated plates were incubated at 37 °C for 24 h. Antimicrobial activity was evaluated by measuring the diameter of the growth inhibition zone surrounding the disc (mm) for eight tested concentrations (from 5% to 0.039%) against the isolated strains. The following intervals of inhibition were considered: (i) no inhibition; (ii) inhibition < 12 mm: weak activity; (iii) 12 mm ≥ inhibition < 20 mm: moderate activity; (iv) inhibition ≥ 20 mm: strong activity [ 46 ].…”

Antimicrobial resistance and mechanisms of epigenetic regulation

“…Raad et al. found that during stationary phase of E. coli , the 3’ UTR-derived FimR2 ncRNA interacted with CsrA, antagonizing its post-transcriptional functions of flagellar and fimbrial biosynthesis, and firmly strengthening the control of bacterial motility and biofilm formation ( Raad et al., 2022 ).…”

“…For instance, the teg58 ncRNA have specific interaction with argGH mRNA (arginine biosynthesis genes) to repress arginine synthesis and biofilm formation in S. aureus (Manna et al, 2022). Raad et al found that during stationary phase of E. coli, the 3' UTR-derived FimR2 ncRNA interacted with CsrA, antagonizing its posttranscriptional functions of flagellar and fimbrial biosynthesis, and firmly strengthening the control of bacterial motility and biofilm formation (Raad et al, 2022).…”

The Effects of L-Lysine-α-oxidase Enzyme and Trichoderma harzianum Rifai Culture Liquid on the Formation of Biofilms by Uropathogenic Multiresistant E. coli

“…Most E. coli strains can form biofilms, which correlates with the multidrug resistance of E. coli isolates [21]. In 2021, Z. Naziri et al found that 99% of the E. coli isolates they studied could form biofilms in vitro [19,22]. In the same year, L. D. Buck described the genes responsible for the formation of biofilms, which can help predict the severity of UTI at the stage of laboratory screening [2].…”