scholarly journals The high-affinity phosphate transporter Pst in Proteus mirabilis HI4320 and its importance in biofilm formation

Microbiology ◽  
2009 ◽  
Vol 155 (5) ◽  
pp. 1523-1535 ◽  
Author(s):  
G. A. O'May ◽  
S. M. Jacobsen ◽  
M. Longwell ◽  
P. Stoodley ◽  
H. L. T. Mobley ◽  
...  
Keyword(s):  
Human Urine ◽  
Proteus Mirabilis ◽  
Biofilm Formation ◽  
Wild Type ◽  
Transposon Mutants ◽  
Tract Infections ◽  
Micro Organisms ◽  
Pst System ◽  
Specific Transport System

Proteus mirabilis causes urinary tract infections (UTIs) in individuals requiring long-term indwelling catheterization. The pathogenesis of this uropathogen is mediated by a number of virulence factors and the formation of crystalline biofilms. In addition, micro-organisms have evolved complex systems for the acquisition of nutrients, including the phosphate-specific transport system, which has been shown to be important in biofilm formation and pathogenesis. A functional Pst system is important during UTIs caused by P. mirabilis HI4320, since transposon mutants in the PstS periplasmic binding protein and the PstA permease protein were attenuated in the CBA mouse model of UTI. These mutants displayed a defect in biofilm formation when grown in human urine. This study focuses on a comparison of the proteomes during biofilm and planktonic growth in phosphate-rich medium and human urine, and microscopic investigations of biofilms formed by the pst mutants. Our data suggest that (i) the Δpst mutants, and particularly the ΔpstS mutant, are defective in biofilm formation, and (ii) the proteomes of these mutants differ significantly from that of the wild-type. Therefore, since the Pst system of P. mirabilis HI4320 negatively regulates biofilm formation, this system is important for the pathogenesis of these organisms during complicated UTIs.

scholarly journals Mannose-Resistant Proteus-Like Fimbriae Are Produced by Most Proteus mirabilis Strains Infecting the Urinary Tract, Dictate the In Vivo Localization of Bacteria, and Contribute to Biofilm Formation

2004 ◽  
Vol 72 (12) ◽  
pp. 7294-7305 ◽  
Author(s):  
Angela M. Jansen ◽  
Virginia Lockatell ◽  
David E. Johnson ◽  
Harry L. T. Mobley
Keyword(s):  
Urinary Tract ◽  
Proteus Mirabilis ◽  
Biofilm Formation ◽  
Constitutive Expression ◽  
Etiologic Agent ◽  
Phase Variable ◽  
Wild Type ◽  
Bladder Tissue ◽  
Tract Infections

ABSTRACT Proteus mirabilis, an etiologic agent of complicated urinary tract infections, expresses mannose-resistant Proteus-like (MR/P) fimbriae whose expression is phase variable. Here we examine the role of these fimbriae in biofilm formation and colonization of the urinary tract. The majority of wild-type P. mirabilis cells in transurethrally infected mice produced MR/P fimbriae. Mutants that were phase-locked for either constitutive expression (MR/P ON) or the inability to express MR/P fimbriae (MR/P OFF) were phenotypically distinct and swarmed at different rates. The number of P. mirabilis cells adhering to bladder tissue did not appear to be affected by MR/P fimbriation. However, the pattern of adherence to the bladder surface was strikingly different. MR/P OFF colonized the lamina propria underlying exfoliated uroepithelium, while MR/P ON colonized the luminal surfaces of bladder umbrella cells and not the exfoliated regions. Wild-type P. mirabilis was usually found colonizing intact uroepithelium, but it occasionally adhered to exfoliated areas. MR/P ON formed significantly more biofilm than either P. mirabilis HI4320 (P = 0.03) or MR/P OFF (P = 0.05). MR/P OFF was able to form a biofilm similar to that of the wild type. MR/P ON formed a three-dimensional biofilm structure as early as 18 h after the initiation of the biofilm, while MR/P OFF and the wild type did not. After 7 days, however, P. mirabilis HI4320 formed a 65-μm-thick biofilm, while the thickest MR/P ON and MR/P OFF biofilms were only 12 μm thick. We concluded that MR/P fimbriae are expressed by most P. mirabilis cells infecting the urinary tract, dictate the localization of bacteria in the bladder, and contribute to biofilm formation.

scholarly journals Antimicrobial and Antibiofilm Activities of Probiotic Lactobacilli on Antibiotic-Resistant Proteus mirabilis

2020 ◽  
Vol 8 (6) ◽  
pp. 960
Author(s):  
Mona Shaaban ◽  
Ola A. Abd El-Rahman ◽  
Bashair Al-Qaidi ◽  
Hossam M. Ashour
Keyword(s):  
Crystal Violet ◽  
Proteus Mirabilis ◽  
Biofilm Formation ◽  
Lactobacillus Casei ◽  
Lactobacillus Reuteri ◽  
Antimicrobial Activities ◽  
Antibiotic Resistant ◽  
Amoxicillin Clavulanic Acid ◽  
Probiotic Lactobacilli ◽  
Tract Infections

The emergence of biofilm-forming, multi-drug-resistant (MDR) Proteus mirabilis infections is a serious threat that necessitates non-antibiotic therapies. Antibiotic susceptibility and biofilm-forming activity of P. mirabilis isolates from urine samples were assessed by disc diffusion and crystal violet assays, respectively. Antimicrobial activities of probiotic Lactobacilli were evaluated by agar diffusion. Antibiofilm and anti-adherence activities were evaluated by crystal violet assays. While most P. mirabilis isolates were antibiotic-resistant to varying degrees, isolate P14 was MDR (resistant to ceftazidime, cefotaxime, amoxicillin-clavulanic acid, imipenem, ciprofloxacin, and amikacin) and formed strong biofilms. Cultures and cell-free supernatants of Lactobacillus casei and Lactobacillus reuteri exhibited antimicrobial and antibiofilm activities. The 1/16 concentration of untreated supernatants of L. casei and L. reuteri significantly reduced mature biofilm formation and adherence of P14 by 60% and 72%, respectively (for L. casei), and by 73% each (for L. reuteri). The 1/8 concentration of pH-adjusted supernatants of L. casei and L. reuteri significantly reduced mature biofilm formation and adherence of P14 by 39% and 75%, respectively (for L. casei), and by 73% each (for L. reuteri). Scanning electron microscopy (SEM) confirmed eradication of P14’s biofilm by L. casei. L. casei and L. reuteri could be utilized to combat Proteus-associated urinary tract infections.

scholarly journals Vitamin C in the Presence of Sub-Inhibitory Concentration of Aminoglycosides and Fluoroquinolones Alters Proteus mirabilis Biofilm Inhibitory Rate

Antibiotics ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 116 ◽  
Author(s):  
Joanna Kwiecińska-Piróg ◽  
Krzysztof Skowron ◽  
Tomasz Bogiel ◽  
Agata Białucha ◽  
Jana Przekwas ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Urinary Tract ◽  
Vitamin C ◽  
Urinary Tract Infections ◽  
Proteus Mirabilis ◽  
Biofilm Formation ◽  
Common Species ◽  
Inhibitory Effect ◽  
Acid Addition ◽  
Tract Infections

Vitamin C has antimicrobial activity and is often used as an oral supplement accompanying antibiotic treatment in urinary tract infections (UTI). Proteus mirabilis is the third common species responsible for UTIs that are mostly treated with fluoroquinolones or aminoglycosides. Treatment of the UTI caused by P. mirabilis is problematic due to the ability to form biofilm on the urinary catheters. The aim of the study was to evaluate the influence of ascorbic acid in combination with antibiotics on P. mirabilis abilities to form biofilm. The susceptibility of P. mirabilis reference strain ATCC® 29906™ and four clinical strains isolated from the urine samples of patients with urinary catheter were evaluated according to EUCAST recommendations. The influence of ascorbic acid (0.4 mg × mL−1) in combination with antibiotics on biofilm formation was evaluated spectrophotometrically. Aminoglycosides at sub-inhibitory concentrations more successfully limited biofilm formation by P. mirabilis strains without ascorbic acid addition. Inhibition rate differences at the lowest concentrations of gentamicin and amikacin were statistically significant (p ≤ 0.05). Ascorbic acid addition to the culture medium limited the inhibitory effect of fluoroquinolones, facilitating biofilm formation by P. mirabilis strains. The addition of ascorbic acid during aminoglycosides therapy may disturb treatment of urinary tract infections related to the presence of P. mirabilis biofilm.

scholarly journals The UbiI (VisC) Aerobic Ubiquinone Synthase Is Required for Expression of Type 1 Pili, Biofilm Formation, and Pathogenesis in Uropathogenic Escherichia coli

2016 ◽  
Vol 198 (19) ◽  
pp. 2662-2672 ◽  
Author(s):  
Kyle A. Floyd ◽  
Courtney A. Mitchell ◽  
Allison R. Eberly ◽  
Spencer J. Colling ◽  
Ellisa W. Zhang ◽  
...  
Keyword(s):  
Urinary Tract ◽  
Biofilm Formation ◽  
Energy Deficit ◽  
Wild Type ◽  
Content Type ◽  
Anoxic Conditions ◽  
E Coli ◽  
Type 1 Pili ◽  
Tract Infections

ABSTRACTUropathogenicEscherichia coli(UPEC), which causes the majority of urinary tract infections (UTI), uses pilus-mediated adherence to initiate biofilm formation in the urinary tract. Oxygen gradients withinE. colibiofilms regulate expression and localization of adhesive type 1 pili. A transposon mutant screen for strains defective in biofilm formation identified theubiI(formerlyvisC) aerobic ubiquinone synthase gene as critical for UPEC biofilm formation. In this study, we characterized a nonpolarubiIdeletion mutant and compared its behavior to that of wild-type bacteria grown under aerobic and anoxic conditions. Consistent with its function as an aerobic ubiquinone-8 synthase, deletion ofubiIin UPEC resulted in reduced membrane potential, diminished motility, and reduced expression of chaperone-usher pathway pili. Loss of aerobic respiration was previously shown to negatively impact expression of type 1 pili. To determine whether this reduction in type 1 pili was due to an energy deficit, wild-type UPEC and theubiImutant were compared for energy-dependent phenotypes under anoxic conditions, in which quinone synthesis is undertaken by anaerobic quinone synthases. Under anoxic conditions, the two strains exhibited wild-type levels of motility but produced diminished numbers of type 1 pili, suggesting that the reduction of type 1 pilus expression in the absence of oxygen is not due to a cellular energy deficit. Acute- and chronic-infection studies in a mouse model of UTI revealed a significant virulence deficit in theubiImutant, indicating that UPEC encounters enough oxygen in the bladder to induce aerobic ubiquinone synthesis during infection.IMPORTANCEThe majority of urinary tract infections are caused by uropathogenicE. coli, a bacterium that can respire in the presence and absence of oxygen. The bladder environment is hypoxic, with oxygen concentrations ranging from 4% to 7%, compared to 21% atmospheric oxygen. This work provides evidence that aerobic ubiquinone synthesis must be engaged during bladder infection, indicating that UPEC bacteria sense and use oxygen as a terminal electron acceptor in the bladder and that this ability drives infection potential despite the fact that UPEC is a facultative anaerobe.

scholarly journals Identification of virulence determinants in uropathogenic Proteus mirabilis using signature-tagged mutagenesis

2008 ◽  
Vol 57 (9) ◽  
pp. 1068-1078 ◽  
Author(s):  
Stephanie D. Himpsl ◽  
C. Virginia Lockatell ◽  
J. Richard Hebel ◽  
David E. Johnson ◽  
Harry L. T. Mobley
Keyword(s):  
Urinary Tract ◽  
Mouse Model ◽  
Proteus Mirabilis ◽  
Virulence Determinants ◽  
Indwelling Catheters ◽  
Cba Mice ◽  
Transposon Mutants ◽  
Tract Infections

The Gram-negative bacterium Proteus mirabilis causes urinary tract infections (UTIs) in individuals with long-term indwelling catheters or those with functional or structural abnormalities of the urinary tract. Known virulence factors include urease, haemolysin, fimbriae, flagella, DsbA, a phosphate transporter and genes involved in cell-wall synthesis and metabolism, many of which have been identified using the technique of signature-tagged mutagenesis (STM). To identify additional virulence determinants and to increase the theoretical coverage of the genome, this study generated and assessed 1880 P. mirabilis strain HI4320 mutants using this method. Mutants with disruptions in genes vital for colonization of the CBA mouse model of ascending UTI were identified after performing primary and secondary in vivo screens in approximately 315 CBA mice, primary and secondary in vitro screens in both Luria broth and minimal A medium to eliminate mutants with minor growth deficiencies, and co-challenge competition experiments in approximately 500 CBA mice. After completion of in vivo screening, a total of 217 transposon mutants were attenuated in the CBA mouse model of ascending UTI. Following in vitro screening, this number was reduced to 196 transposon mutants with a probable role in virulence. Co-challenge competition experiments confirmed significant attenuation for 37 of the 93 transposon mutants tested, being outcompeted by wild-type HI4320. Following sequence analysis of the 37 mutants, transposon insertions were identified in genes including the peptidyl-prolyl isomerases surA and ppiA, glycosyltransferase cpsF, biopolymer transport protein exbD, transcriptional regulator nhaR, one putative fimbrial protein, flagellar M-ring protein fliF and hook protein flgE, and multiple metabolic genes.

scholarly journals Escherichia coliO157:H7 responds to phosphate starvation by modifying LPS involved in biofilm formation

2019 ◽  
Author(s):  
Philippe Vogeleer ◽  
Antony T. Vincent ◽  
Samuel M. Chekabab ◽  
Steve J. Charette ◽  
Alexey Novikov ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Biofilm Formation ◽  
Inorganic Phosphate ◽  
Type Strain ◽  
Wild Type Strain ◽  
Pho Regulon ◽  
Wild Type ◽  
E Coli ◽  
Pi Starvation ◽  
Pst System

ABSTRACTIn open environments such as water, enterohemorrhagicEscherichia coliO157:H7 responds to inorganic phosphate (Pi) starvation by inducing the Pho regulon controlled by PhoB. The phosphate-specific transport (Pst) system is the high-affinity Pi transporter. In the Δpstmutant, PhoB is constitutively activated and regulates the expression of genes from the Pho regulon. InE. coliO157:H7, the Δpstmutant, biofilm, and autoagglutination were increased. In the double-deletion mutant ΔpstΔphoB, biofilm and autoagglutination were similar to the wild-type strain, suggesting that PhoB is involved. We investigated the relationship between PhoB activation and enhanced biofilm formation by screening a transposon mutant library derived from Δpstmutant for decreased autoagglutination and biofilms mutants. Lipopolysaccharide (LPS) genes involved in the synthesis of the LPS core were identified. Transcriptomic studies indicate the influence of Pi-starvation andpstmutation on LPS biosynthetic gene expression. LPS analysis indicated that the O-antigen was deficient in the Δpstmutant. Interestingly,waaH, encoding a glycosyltransferase associated with LPS modifications inE. coliK-12, was highly expressed in the Δpstmutant ofE. coliO157:H7. Deletion ofwaaHfrom the Δpstmutant and from the wild-type strain grown in Pi-starvation conditions decreased the biofilm formation but without affecting LPS. Our findings suggest that LPS core is involved in the autoagglutination and biofilm phenotypes of the Δpstmutant and that WaaH plays a role in biofilm in response to Pi-starvation. This study highlights the importance of Pi-starvation in biofilm formation of E. coli O157:H7, which may affect its transmission and persistence.IMPORTANCEEnterohemorrhagicEscherichia coliO157:H7 is a human pathogen responsible for bloody diarrhea and renal failures. In the environment, O157:H7 can survive for prolonged periods of time under nutrient-deprived conditions. Biofilms are thought to participate in this environmental lifestyle. Previous reports have shown that the availability of extracellular inorganic phosphate (Pi) affected bacterial biofilm formation; however, nothing was known about O157:H7 biofilm formation. Our results show that O157:H7 membrane undergoes modifications upon PhoB activation leading to increased biofilm formation. A mutation in the Pst system results in reduced amount of the smooth type LPS and that this could influence the biofilm composition. This demonstrates how theE. coliO157:H7 adapts to Pi starvation increasing its ability to occupy different ecological niches.

scholarly journals Effect of Ibicella lutea on uropathogenic Proteus mirabilis growth, virulence, and biofilm formation

2009 ◽  
Vol 3 (10) ◽  
pp. 762-770 ◽  
Author(s):  
Vanessa Sosa ◽  
Pablo Zunino
Keyword(s):  
Proteus Mirabilis ◽  
Biofilm Formation ◽  
South American ◽  
Antimicrobial Drugs ◽  
Bacterial Growth Rate ◽  
Swarming Motility ◽  
Bacterial Morphology ◽  
Indigenous Plant ◽  
Therapeutic Problem ◽  
Tract Infections

Background: Proteus mirabilis, an important uropathogen that can cause complicated urinary tract infections (UTI), has emerged as a therapeutic problem following mutations that compromise the use of antimicrobial drugs. Due to the serious effects associated with uropathogenic P. mirabilis and the problems related to the use of antibiotics, it is necessary to develop alternative strategies for its control. The objective of this study was to assess the effect of Ibicella lutea extract, a South American indigenous plant, on growth, virulence and biofilm production of uropathogenic P. mirabilis. Methodology:  This study was based on the extract generation and the assessment of its effect on bacterial features related to virulence. These assays involved determination of antibacterial activity, swarming motility, Western blot to assess expression of fimbriae and flagella, biofilms formation, haemagglutination, haemolysis, and electron microscopy.   Results and Conclusions: I. lutea extract had an effect on bacterial growth rate and bacterial morphology. It also affected P. mirabilis swarming differentiation, hemagglutination and biofilm formation on glass and polystyrene. These findings suggest that I. lutea may have a role as an agent for the control of P. mirabilis UTI.

Chlorpromazine-impregnated catheters as a potential strategy to control biofilm-associated urinary tract infections

2019 ◽  
Vol 14 (12) ◽  
pp. 1023-1034 ◽  
Author(s):  
José JC Sidrim ◽  
Bruno R Amando ◽  
Francisco IF Gomes ◽  
Marilia SMG do Amaral ◽  
Paulo CP de Sousa ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Urinary Tract ◽  
Klebsiella Pneumoniae ◽  
Urinary Tract Infections ◽  
Proteus Mirabilis ◽  
Biofilm Formation ◽  
Antibiofilm Activity ◽  
Potential Strategy ◽  
Tract Infections

Aim: This study proposes the impregnation of Foley catheters with chlorpromazine (CPZ) to control biofilm formation by Escherichia coli, Proteus mirabilis and Klebsiella pneumoniae. Materials & methods: The minimum inhibitory concentrations (MICs) for CPZ and the effect of CPZ on biofilm formation were assessed. Afterward, biofilm formation and the effect of ciprofloxacin and meropenem (at MIC) on mature biofilms grown on CPZ-impregnated catheters were evaluated. Results: CPZ MIC range was 39.06–625 mg/l. CPZ significantly reduced (p < 0.05) biofilm formation in vitro and on impregnated catheters. In addition, CPZ-impregnation potentiated the antibiofilm activity of ciprofloxacin and meropenem. Conclusion: These findings bring perspectives for the use of CPZ as an adjuvant for preventing and treating catheter-associated urinary tract infections.

scholarly journals The N-Terminal Domain of Enterococcal Surface Protein, Esp, Is Sufficient for Esp-Mediated Biofilm Enhancement in Enterococcus faecalis

2005 ◽  
Vol 187 (17) ◽  
pp. 6213-6222 ◽  
Author(s):  
Preeti M. Tendolkar ◽  
Arto S. Baghdayan ◽  
Nathan Shankar
Keyword(s):  
Enterococcus Faecalis ◽  
Biofilm Formation ◽  
Tandem Repeats ◽  
Full Length ◽  
Specific Factor ◽  
Dependent Manner ◽  
Wild Type ◽  
Specific Domain ◽  
Terminal Domain ◽  
Tract Infections

ABSTRACT Enterococci have emerged as one of the leading causes of nosocomial bloodstream, surgical site, and urinary tract infections. More recently, enterococci have been associated with biofilms, which are bacterial communities attached to a surface and encased in an extracellular polymeric matrix. The enterococcal cell surface-associated protein, Esp, enhances biofilm formation by Enterococcus faecalis in a glucose-dependent manner. Mature Esp consists of a nonrepeat N-terminal domain and a central region made up of two types of tandem repeats followed by a C-terminal membrane-spanning and anchor domain. This study was undertaken to localize the specific domain(s) of Esp that plays a role in Esp-mediated biofilm enhancement. To achieve this objective, we constructed in-frame deletion mutants expressing truncated forms of Esp in an isogenic background. By comparing strains expressing the mutant forms of Esp to those expressing wild-type Esp, we found that the strain expressing Esp lacking the N-terminal domain formed biofilms that were quantitatively less in biovolume than the strain expressing wild-type Esp. Furthermore, an E. faecalis strain expressing only the N-terminal domain of Esp fused to a heterologous protein anchor formed biofilms that were quantitatively similar to those formed by a strain expressing full-length Esp. This suggested that the minimal region contributing to Esp-mediated biofilm enhancement in E. faecalis was confined to the nonrepeat N-terminal domain. Expression of full-length E. faecalis Esp in heterologous host systems of esp-deficient Lactococcus lactis and Enterococcus faecium did not enhance biofilm formation as was observed for E. faecalis. These results suggest that Esp may require interaction with an additional E. faecalis-specific factor(s) to result in biofilm enhancement.

scholarly journals Biofilm Formation by Psychrobacter arcticus and the Role of a Large Adhesin in Attachment to Surfaces

2013 ◽  
Vol 79 (13) ◽  
pp. 3967-3973 ◽  
Author(s):  
Shannon M. Hinsa-Leasure ◽  
Cassandra Koid ◽  
James M. Tiedje ◽  
Janna N. Schultzhaus
Keyword(s):  
Biofilm Formation ◽  
Time Course ◽  
Microtiter Plate ◽  
Bacterial Attachment ◽  
Wild Type ◽  
Microtiter Plate Assay ◽  
Content Type ◽  
Reading Frame ◽  
Transposon Mutants

ABSTRACTPsychrobacter arcticusstrain 273-4, an isolate from a Siberian permafrost core, is capable of forming biofilms when grown in minimal medium under laboratory conditions. Biofilms form at 4 to 22°C when acetate is supplied as the lone carbon source and with 1 to 7% sea salt.P. arcticusis also capable of colonizing quartz sand. Transposon mutagenesis identified a gene important for biofilm formation byP. arcticus. Four transposon mutants were mapped to a 20.1-kbp gene, which is predicted to encode a protein of 6,715 amino acids (Psyc_1601). We refer to this open reading frame ascat1, for cold attachment gene 1. Thecat1mutants are unable to form biofilms at levels equivalent to that of the wild type, and there is no impact on the planktonic growth characteristics of the strains, indicating a specific role in biofilm formation. Through time course studies of the static microtiter plate assay, we determined thatcat1mutants are unable to form biofilms equivalent to that of the wild type under all conditions tested. In flow cell experiments,cat1mutants initially are unable to attach to the surface. Over time, however, they form microcolonies, an architecture very different from that produced by wild-type biofilms. Our results demonstrate that Cat1 is involved in the initial stages of bacterial attachment to surfaces.

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