The RNA chaperone Hfq is involved in stress tolerance and virulence in uropathogenic proteus mirabilis
Journal
PLoS ONE
Journal Volume
9
Journal Issue
1
Pages
e85626
Date Issued
2014
Author(s)
Abstract
Hfq is a bacterial RNA chaperone involved in the riboregulation of diverse genes via small noncoding RNAs. Here, we show that Hfq is critical for the uropathogenic Proteus mirabilis to effectively colonize the bladder and kidneys in a murine urinary tract infection (UTI) model and to establish burned wound infection of the rats. In this regard, we found the hfq mutant induced higher IL-8 and MIF levels of uroepithelial cells and displayed reduced intra-macrophage survival. The loss of hfq affected bacterial abilities to handle H2O2 and osmotic pressures and to grow at 50uC. Relative to wild-type, the hfq mutant had reduced motility, fewer flagella and less hemolysin expression and was less prone to form biofilm and to adhere to and invade uroepithelial cells. The MR/P fimbrial operon was almost switched to the off phase in the hfq mutant. In addition, we found the hfq mutant exhibited an altered outer membrane profile and had higher RpoE expression, which indicates the hfq mutant may encounter increased envelope stress. With the notion of envelope disturbance in the hfq mutant, we found increased membrane permeability and antibiotic susceptibilities in the hfq mutant. Finally, we showed that Hfq positively regulated the RpoS level and tolerance to H 2O2 in the stationary phase seemed largely mediated through the Hfqdependent RpoS expression. Together, our data indicate that Hfq plays a critical role in P. mirabilis to establish UTIs by modulating stress responses, surface structures and virulence factors. This study suggests Hfq may serve as a scaffold molecule for development of novel anti-P. mirabilis drugs and P. mirabilis hfq mutant is a vaccine candidate for preventing UTIs. ? 2014 Wang et al.
SDGs
Other Subjects
ampicillin; chaperone; chaperone protein Hfq; chloramphenicol; ciprofloxacin; gentamicin; hemolysin; hydrogen peroxide; interleukin 8; migration inhibition factor; mutant protein; polymyxin B; protein RpoE; spectinomycin; streptomycin; tetracycline; unclassified drug; bacterial protein; chaperone; cytokine; primer DNA; animal cell; animal experiment; animal model; antibiotic sensitivity; article; bacterial colonization; bacterial growth; bacterial membrane; bacterial virulence; biofilm; bladder; burn infection; cell adhesion; cell motility; cell survival; controlled study; epithelium cell; flagellum; gene; gene loss; genotype; hfq gene; homologous recombination; kidney; macrophage; male; membrane permeability; minimum inhibitory concentration; mouse; murine model; nonhuman; operon; osmotic pressure; pathogenesis; phenotype; protein expression; Proteus mirabilis; rat; stress; temperature; urinary tract infection; uroepithelial cell; uropathogenic Proteus mirabilis; amino acid sequence; animal; biosynthesis; C57BL mouse; chemistry; gene inactivation; genetics; metabolism; microbiology; molecular genetics; nucleotide sequence; pathogenicity; physiology; Proteus mirabilis; real time polymerase chain reaction; scanning electron microscopy; sequence homology; urinary tract; virulence; Wistar rat; Amino Acid Sequence; Animals; Bacterial Proteins; Base Sequence; Biofilms; Cytokines; DNA Primers; Gene Knockout Techniques; Hydrogen Peroxide; Male; Mice; Mice, Inbred C57BL; Microscopy, Electron, Scanning; Molecular Chaperones; Molecular Sequence Data; Osmotic Pressure; Proteus mirabilis; Rats; Rats, Wistar; Real-Time Polymerase Chain Reaction; Sequence Homology, Amino Acid; Urinary Tract; Virulence
Type
journal article