fimH Gene Research Articles

Antibiotic Resistance, Biofilm Formation, and Identification of FimH and FimA Adhesion Genes in Uropathogenic Escherichia Coli (UPEC) Isolated from Patients in Baghdad Province

Urinary tract infections (UTIs) are one of the most common infectious disorders worldwide. The most frequent cause of UTIs is uropathogenic Escherichia coli (UPEC). The current study is designed to assess the resistance of antibiotics, the formation of biofilm, and the detection of adhesion genes in E. coli isolated from patients with UTIs. A hundred and fifty samples were collected from patients with confirmed UTIs in Baghdad province during the period of October 2022 to February 2023. Isolation and identification of E. coli were performed using cultural characteristics, gram staining, and biochemical examination, and the results indicated that 52 (35%) isolates were identified as E. coli. Eleven antibiotic discs were utilized to estimate the sensitivity of E. coli isolates. 98% of isolates were resistant to ampicillin, followed by 75.5% of isolates resistant to both trimethoprim/sulfamethoxazole and fosfomycin, followed by 73.5, 71.4, 67.3, 53.1, and 6.1% of isolates resistant to imipenem, ceftazidime, nitrofurantoin, cefepime, and amikacin. All isolates were sensitive to piperacillin-tazobactam, ciprofloxacin, and aztreonam at 100%, 100%, and 98%, respectively. The microtiter plate method was utilized to estimate the ability of E. coli to form biofilm. The majority of isolates (69.2%; n = 36) were moderate biofilm producers, while 19.2% (n = 10) and 11.5% (n = 6) of isolates were strong and weak biofilm producers, respectively. Polymerase Chain Reactions (PCR) were applied to determine the gene expression level of adhesion genes (fimH and fimA genes). Forty isolates harbored both fimH and fimA genes.

Suppression of virulence factors of uropathogenic Escherichia coli by Trans-resveratrol and design of nanoemulgel

BackgroundDevelopment of multidrug resistance in Uropathogenic Escherichia coli (UPEC) makes treatment of Urinary Tract Infections (UTIs) a major challenge. This study was conducted to investigate the effect of trans-resveratrol (t-RSV) at a subinhibitory concentration (sub-MIC-t-RSV) on phenotypic and genotypic expression of virulence factors of clinical isolates of UPEC and develop a nanoformulation of t-RSV. Fifty-five clinical UPEC strains were investigated for the presence of virulence factors by phenotypic methods and PCR detection of virulence genes. The effect of sub-MIC-t-RSV was studied on the phenotypic and genotypic expression of virulence factors. t-RSV-loaded nanoemulgel formulation was prepared and characterized.ResultsOut of the 55 tested isolates, 50.9% were biofilm producers, 23.6% showed both mannose-sensitive and mannose-resistant hemagglutination, 21.8% were serum-resistant, 18.2% were hemolysin producers, while 36.4% showed cytotoxic effect on HEp-2 cells. A total of 25.5% of the isolates harbor one or more of hly-A, cnf-1 and papC genes, while 54.5% were positive for one or more of fimH, iss and BssS genes. A concentration of 100 µg/mL of t-RSV effectively downregulates the phenotypic and genotypic expression of the virulence factors in positive isolates. A stable t-RSV-nanaoemulgel with droplet size of 180.3 nm and Zetapotential of -46.9 mV was obtained.ConclusionThe study proves the effective role of t-RSV as an antivirulence agent against clinical UPEC isolates in vitro and develops a stable t-RSV-nanoemulgel formulation to be assessed in vivo. The promising antibacterial and antivirulence properties of t-RSV place this natural compound to be a better alternative in the treatment of persistent UTIs.

Distribution of chaperone-usher fimbriae and curli fimbriae among uropathogenic Escherichia coli

BackgroundIn the present study, we aimed to determine the frequency of the csgA, fimH, mrkD, foc, papaGI, papGII and papGIII genes, to provide and to design fimbrial adhesin gene (FAG) patterns and profiles for the isolated uropathogenic Escherichia coli (UPEC) strains.MethodsThe enrollment of 108 positive urine samples was performed during seven months, between January 2022 and July 2022. The UPEC strains were confirmed through the standard microbiological and biochemical tests. The antimicrobial susceptibility test was performed through the Kirby–Bauer disc diffusion method. Molecular screening of FAGs was done through the polymerase chain reaction technology. The statistical analyses including chi square and Fisher’s exact tests were performed to interpret the obtained results in the present study.ResultsAs the main results, the antimicrobial resistance (AMR) patterns,multi- (MDR) and extensively drug-resistance (XDR) patterns and FAG patterns were designed and provided. fimH (93.3%), csgA (90.4%) and papG (37.5%) (papGII (30.8%)) genes were recognized as the top three FAGs, respectively. Moreover, the frequency of csgA-fimH gene profile was identified as the top FAG pattern (46.2%) among the others. The isolates bearing csgA-fimH gene profile were armed with a versatile of phenotypic AMR patterns. In the current study, 27.8%, 69.4% and 1.9% of the UPEC isolates were detected as extended-spectrum ß-lactamases (ESBLs) producers, MDR and XDR strains, respectively.ConclusionsIn conclusion, detection, providing and designing of patterns and profiles in association with FAGs, AMR feature in UPEC strains give us an effective option to have a successful and influential prevention for both of UTIs initiation and AMR feature.

Relationship between virulence and carbapenem resistance phenotype of Klebsiella pneumoniae from blood infection: identification of a carbapenem-resistant and hypervirulent strain.

To investigate the relationship between the virulence and the carbapenem resistance phenotype of Klebsiella pneumoniae from blood infection, and to identify carbapenem-resistant and hypervirulent Klebsiella pneumoniae (CR-HVKP)strains. A total of 192 Klebsiella pneumoniae strains were isolated from blood culture of patients with bloodstream infections from 2016 to 2019, of which 96 isolates were carbapenem-resistant Klebsiella pneumoniae (CRKP) and 96 were carbapenem-sensitive Klebsiella pneumoniae (CSKP). The drug susceptibility was detected by VITEK-2 automatic microbial analyzer; carbapenemase genes, virulence genes and capsule typing were detected by polymerase chain reaction; the high viscosity phenotype of strains was detected by string test, and the genome characteristics of CR-HVKP were detected by whole genome sequencing. Serum killing and biofilm formation test were used to further verify the virulence of CR-HVKP. There were significant differences in drug resistance to common antibiotics, except for minocycline between CSKP and CRKP isolates (all P<0.05). 92 out of 96 CRKP isolates carried carbapenemase genes, mainly blaKPC-2. The string tests were positive in 4 isolates of CRKP and 36 isolates of CSKP (P<0.05). The detection rates of virulence genes Kfu, aerobictin, iutA, ybtS, rmpA, magA, allS, and capsule antigen K1 and K2 in CSKP group were significantly higher than those in CRKP group (all P<0.05). One HVKP strain was detected in the CRKP group (CR-HVKP) and 36 HVKP was detected in the CSKP group (P<0.05). The CR-HVKP strain belonged to the MLST412, serotype K57, expressed iutA, entB, mrkD, fimH, and rmpA virulence genes, and showed strong biofilm formation and significantly increased serum resistance. Whole genome sequencing results showed that this CR-HVKP isolate carried blaSHV-145, blaTEM-1, blaCTX-M-3, fosA6, oqxA5, oqxB26, and aac(3)-IId resistance genes, accompanied by abnormalities in outer membrane protein K (OmpK) 35 and OmpK36. The drug resistance of CRKP is significantly higher than that of CSKP, while CRKP carrying fewer virulence genes in both number and types compared to CSKP. A new MLST type of carbapenem-resistant and hypervirulent Klebsiella pneumoniae strain has been detected, which requires clinical awareness and epidemiological monitoring.

Antibiotic resistance and its correlation with biofilm formation and virulence genes in Klebsiella pneumoniae isolated from wounds.

Klebsiella pneumoniae is the most important species of the Klebsiella genus and often causes hospital infections. These bacteria have a high resistance to most of the available drugs, which has caused concern all over the world. In this study, we investigated the antibiotic resistance profile and the ability to produce extended-spectrum beta-lactamase (ESBL) among K. pneumoniae isolates, and then we investigated the relationship between these two factors with biofilm formation and the prevalence of different virulence genes. In this study, 130 isolates of K. pneumoniae isolated from wounds were investigated. The antibiotic resistance of the isolates was evaluated by the disk diffusion method. The microtiter plate method was used to measure biofilm formation. The prevalence of virulence genes was detected by multiplex PCR. Among the examined isolates, 85.3% showed multidrug resistance. 87.6% of the isolates were ESBL-positive. Imipenem, meropenem, and fosfomycin were the most effective drugs. The ability of the isolates to produce biofilm was strong (80%), moderate (12.3%), and weak (7.6%), respectively. fimH, mrKD, entB, and tolC virulence genes were observed in all isolates. High prevalence of antibiotic resistance (especially multidrug resistance), high prevalence of ESBL-producing isolates, the ability of all isolates to biofilm formation, and the presence of fimH, mrKD, entB, and tolC virulence genes in all isolates show the importance of these factors in the pathogenesis of K. pneumoniae isolates in Iraq.

Thymol Enhances Antibiotic Sensitivity and Inhibits Biofilm Formation in Urinary Tract Infection Isolates of Escherichia coli From Gilan Province, Iran

Background: The present study aimed to investigate the effect of thymol on growth inhibition, biofilm inhibition, and antibiotic sensitivity of Escherichia coli isolated from urinary tract infection in Gilan province, Iran. Methods: The disc diffusion and broth microdilution methods were used to investigate the antimicrobial effect of thymol on 30 urinary tract infection isolates of E. coli. Additionally, the time-kill assay was used to investigate the effectiveness of thymol at different time intervals over a period of 24 hours. The anti-biofilm effect of thymol was investigated using the microplate method. Moreover, the effect of thymol on fimH gene expression was investigated. To investigate the effect of thymol on the sensitivity of E. coli isolates to cefotaxime and ciprofloxacin, the checkerboard assay was used. Results: ThymolFF exhibits inhibitory effects on the growth of E. coli isolates and the diameter of the zone of growth inhibition caused by 5 mg of thymol in the studied isolates varied between 15 and 30 mm and minimum inhibitory concentration (MIC) of thymol against MDR E. coli isolates ranged from 1 to 4 mg/mL. Depending on the concentration and the exposure time, bacterial killing was promoted by thymol treatment. The use of thymol decreased the biofilm formation of the isolates by more than 50% compared to the control and also bacterial treatment with thymol led to down-regulation of the fimH gene. Furthermore, enhancing the antibacterial effect of cefotaxime and ciprofloxacin by thymol was demonstrated. Conclusion: The present study found that thymol, a terpenoid of plant origin, exhibited strong killing efficiency, inhibiting the biofilm formation, and enhanced antibiotic sensitivity of E. coli isolated from urinary tract infection.

Detection fimH Gene in The Urine of UTI Patients at The Puskesmas Banyuanyar, as a Marker for The Presence of Escherichia coli

Urinary Tract Infection (UTI) is a bacterial infection characterized by a urine culture showing bacteriuria with bacterial counts exceeding 100,000 per milliliter of urine. Polymerase Chain Reaction (PCR) is a method that utilizes in-vitro enzymatic reactions to amplify specific DNA targets. This process synthesizes new DNA strands complementary to the target sequences using enzymes and oligonucleotide primers within a thermocycler. The fimH gene is among the most important of the UPEC strains and is associated with severe urinary tract infections. The aim of this study was to identify the presence of the fimH gene in urine samples from UTI patients at the Puskesmas Banyuanyar in Surakarta using Polymerase Chain Reaction (PCR). The research employed the Quota Sampling Technique, collecting a total of five urine samples from individuals diagnosed with urinary tract infections. The results of the control isolates using pure Escherichia coli isolates showed that the fimH gene PCR amplified control with annealing temperature of 52°C. The analysis of clinical isolates of Escherichia coli from the urine of urinary tract infection patients revealed that the fimH gene was PCR amplified in all five samples.

Antimicrobial efficiency of bromhexine hydrochloride against endometritis-causing Escherichia coli and Trueperella pyogenes in bovines.

In this study, the main agents associated with endometritis in cows in the state of Santa Catarina, Brazil, were identified and the resistance profile and virulence mechanisms of the bacterial isolates were evaluated. Isolates of Escherichia coli and Trueperella pyogenes were tested for their biofilm forming ability and the antimicrobial action of bromhexine hydrochloride in combination with other antimicrobials. A total of 37 uterine lavage samples were collected from cows with endometritis. Of the 55 bacteria isolated, 25.4% were identified as T. pyogenes and 16.3% as E. coli. The bacterial isolates showed greater resistance to sulfamethoxazole + trimethoprim (58.2%) and tetracycline (56.3%). Among the species, E. coli showed the highest resistance rates, with 100% of isolates showing resistance to amoxicillin, streptomycin, and gentamicin. The results of the minimum inhibitory concentration for the T. pyogenes isolates showed that 91.6% of the isolates were resistant to enrofloxacin and tetracycline, and 75% were resistant to ceftiofur and sulfamethoxazole + trimethoprim. All E. coli and T. pyogenes isolates showed biofilm forming ability. The plo, fimA, and nanH genes were identified in 100% of T. pyogenes isolates. In parallel, 100% of E. coli isolates had the fimH gene, and 11.1% had the csgD gene. Bromhexine hydrochloride showed antimicrobial activity against 100% of E. coli isolates and 66.6% of T. pyogenes isolates. Furthermore, when associated with antimicrobials, bromhexine hydrochloride has a synergistic and additive effect, proving to be an option in the treatment of endometritis in cows and an alternative for reducing the use of antimicrobials.

Evaluation of adhesin genes and risk factors associated with urinary tract infections by drug-resistant uropathogenic Escherichia coli in North of Iran.

Uropathogenic Escherichia coli (UPEC) isolates, have a wide variety of virulence factors to promote colonization and survival in the urinary tract. This study aimed to evaluate adhesin genes, biofilm formation ability, antibiotic resistance profiles of UPEC strains, and the related risk factors in patients with UTIs caused by drug-resistant UPEC. A total of 105 UPEC isolates were evaluated for biofilm formation using 96-well microtiter plates, the presence of adhesin genes by PCR assay and the antimicrobial susceptibility pattern using the disk diffusion method. Demographic and clinical characteristics of patients were investigated to identify predisposing factors for drug-resistant isolates. Out of 105 UPEC isolates, 84.8% were positive for biofilm formation. Biofilm-producing isolates exhibited a significantly higher prevalence of fimH, kpsMTII, csgA, afa/draBC, and pap adhesin genes compared to non-biofilm-producing strains (p < 0.05). The results also revealed that 52.4% of the isolates were ESBL-producing, and 84.8% were multidrug-resistant (MDR). Further analysis of antibiotic susceptibility among ESBL-producing strains showed the highest resistance rates to ampicillin, ciprofloxacin, and trimethoprim-sulfamethoxazole. Conversely, the highest susceptibility, in addition to carbapenems, was observed for fosfomycin, amikacin, cefoxitin, and nitrofurantoin. We identified hypertension as a potential risk factor for infection with ESBL-producing UPEC strains. Our results revealed a significant rate of drug resistance among UPEC isolates obtained from UTIs in our region. This underscores the importance of monitoring the empirical use of antibiotics and identifying specific risk factors in our geographical area to guide the selection of appropriate empirical treatment for UTIs.

Study of Biofilm, Virulence Genes, and Risk Factors in Urinary Catheter-Associated Escherichia coli Infections

Background: Catheter-associated urinary tract infections (CAUTIs) are prevalent among intensive care unit (ICU) patients and pose significant health risks. The causative agent, Escherichia coli, is commonly associated with these infections. Objectives: The primary objective of our study was to evaluate various risk factors associated with CAUTIs. Additionally, we investigated the capacity of E. coli to form biofilms and the presence of virulence genes in these infections. Methods: We conducted a prospective study involving 204 patients admitted to ICUs with indwelling urinary catheters who subsequently developed CAUTIs. The isolated pathogen in all cases was E. coli. We subjected the isolated E. coli strains to microbiological analyses, including biofilm formation assays and polymerase chain reaction (PCR) for detecting virulence genes (pap-C, fim-H, sfa, afa, hylA, and cnf1). Results: Our findings revealed that 111 out of 204 isolated E. coli strains (54.4%) could form biofilms in vitro. Among the detected virulence genes, fim-H was the most frequently observed (32.4%), followed by pap-C (14.2%), sfa (12.3%), and afa1 (11.3%). The least frequently detected genes were cnf1 (3.9%) and hylA (2.5%). Notably, there was a significant association between the presence of fim-H, pap-C, afa1, and hylA genes and the ability of E. coli to form biofilms (P = 0.001, P = 0.001, P = 0.04, P = 0.046, respectively). Regarding the timing of CAUTIs, most cases occurred 7 - 10 days after catheter insertion (48.53%), followed by 3 - 6 days after insertion (45.59%). The least frequent occurrence was after 10 days from catheter insertion (5.86%). Early presence of CAUTIs (within 3 - 6 days) was significantly associated with diabetes mellitus (DM) and post-operative complications (both with P = 0.046). Furthermore, we observed a significant increase in the presence of the cnf1 gene in cases of early CAUTIs (3 - 6 days after catheter insertion, P = 0.001). Conclusions: Our study highlights the importance of understanding the risk factors, virulence genes, and biofilm formation capacity in E. coli-related CAUTIs. These findings may guide preventive strategies and improve patient outcomes.

Comparing antibiotic resistance and virulence profiles of Enterococcus faecium, Klebsiella pneumoniae, and Pseudomonas aeruginosa from environmental and clinical settings

Antibiotic resistance and virulence profiles of Enterococcus faecium, Klebsiella pneumoniae, and Pseudomonas aeruginosa, isolated from water sources collected in informal settlements, were compared to clinical counterparts. Cluster analysis using repetitive extragenic palindromic sequence-based polymerase chain reaction (REP-PCR) indicated that, for each respective species, low genetic relatedness was observed between most of the clinical and environmental isolates, with only one clinical P. aeruginosa (PAO1) and one clinical K. pneumoniae (P2) exhibiting high genetic similarity to the environmental strains. Based on the antibiograms, the clinical E. faecium Ef CD1 was extensively drug resistant (XDR); all K. pneumoniae isolates (n = 12) (except K. pneumoniae ATCC 13883) were multidrug resistant (MDR), while the P. aeruginosa (n = 16) isolates exhibited higher susceptibility profiles. The tetM gene (tetracycline resistance) was identified in 47.4 % (n = 6 environmental; n = 3 clinical) of the E. faecium isolates, while the blaKPC gene (carbapenem resistance) was detected in 52.6 % (n = 7 environmental; n = 3 clinical) and 15.4 % (n = 2 environmental) of the E. faecium and K. pneumoniae isolates, respectively. The E. faecium isolates were predominantly poor biofilm formers, the K. pneumoniae isolates were moderate biofilm formers, while the P. aeruginosa isolates were strong biofilm formers. All E. faecium and K. pneumoniae isolates were gamma (γ)-haemolytic, non-gelatinase producing (E. faecium only), and non-hypermucoviscous (K. pneumoniae only), while the P. aeruginosa isolates exhibited beta (β)-haemolysis and produced gelatinase. The fimH (type 1 fimbriae adhesion) and ugE (uridine diphosphate galacturonate 4-epimerase synthesis) virulence genes were detected in the K. pneumoniae isolates, while the P. aeruginosa isolates possessed the phzM (phenazine production) and algD (alginate biosynthesis) genes. Similarities in antibiotic resistance and virulence profiles of environmental and clinical E. faecium, K. pneumoniae, and P. aeruginosa, thus highlights the potential health risks posed by using environmental water sources for daily water needs in low-and-middle-income countries.

Type 1 fimbrial phase variation in multidrug-resistant asymptomatic uropathogenic Escherichia coli clinical isolates upon adherence to HTB-4 cells.

The adherence of bladder uroepithelial cells, subsequent expression, and regulation of type 1 fimbrial genes (key mediator of attachment) in clinical multidrug-resistant uropathogenic Escherichia coli (MDR-UPECs) isolated from individuals with asymptomatic bacteriuria (ABU) remain unexplored till date. Therefore, this study aimed to investigate the underlying molecular mechanisms associated with the adherence of clinical MDR-ABU-UPECs to human a uroepithelial cell line (HTB-4), both in the absence and presence of D-Mannose. These investigations focused on phase variation, expression, and regulation of type 1 fimbriae and were compared to a prototype ABU-strain (E. coli 83972) and symptomatic MDR-UPECs. Discordant to the ABU prototype strain, MDR-ABU-UPECs exhibited remarkable adhesive capacity that was significantly reduced after D-mannose exposure, fairly like the MDR symptomatic UPECs. The type 1 fimbrial phase variation, determined by the fim switch analysis, asserted the statistically significant incidence of "both OFF and ON" orientation among the adherent MDR-ABU-UPECs with a significant reduction in phase-ON colonies post-D-mannose exposure, akin to the symptomatic ones. This was indicative of an operative and alternating type 1 fimbrial phase switch. The q-PCR assay revealed a coordinated action of the regulatory factors; H-NS, IHF, and Lrp on the expression of FimB and FimE recombinases, which further controlled the function of fimH and fimA genes in ABU-UPECs, similar to symptomatic strains. Therefore, this study is the first of its kind to provide an insight into the regulatory crosstalk of different cellular factors guiding the adhesion of ABU-UPECs to the host. Additionally, it also advocated for the need to accurately characterize ABU-UPECs.

Virulent Klebsiella pneumoniae ST11 clone carrying blaKPC and blaNDM from patients with and without COVID-19 in Brazil.

Investigated and compared the occurrence of virulence genes fimH, mrkD, irp2, entB, cps, rmpA, and wabG, resistance genes blaKPC and blaNDM, and the genetic variability and clonal relationship of 29 Klebsiella pneumoniae clinical isolates of patients with and without COVID-19, from a hospital in Brazil. All isolates were resistant to beta-lactams. The genes were investigated by PCR, and for molecular typing, enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) and MLST were used. The detection of blaNDM was greater (n=23) when compared to that of blaKPC (n=14). The virulence genes that most occurred were fimH, entB, cps, and wabG, which are responsible for adhesins, siderophore enterobactin, capsule, and lipopolysaccharides, respectively. Among the isolates, 21 distinct genetic profiles were found by ERIC-PCR, with multiclonal dissemination. Four isolates belonged to the ST11 clone. The occurrence of the ST11 is worrying as it is a high-risk clone involved in the dissemination of virulent strains throughout the world.

Carbapenemase Genes, Virulence Genes, and Molecular Epidemiology of Carbapenem-Resistant Klebsiella pneumoniae Derived From Bloodstream Infections

To investigate the clinical characteristics and molecular epidemiology of carbapenem-resistant Klebsiella pneumoniae (CRKP) isolated from patients with bloodstream infections in a large tertiary-care general hospital in Southwest China. A total of 131 strains of non-repeating CRKP were collected from the blood cultures of patients who had bloodstream infections in 2015-2019. The strains were identified by VITEK-2, a fully automated microbial analyzer, and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry. The minimum inhibitory concentration (MIC) was determined by microbroth dilution method. The common carbapenemase resistant genes and virulence factors were identified by PCR. Homology analysis was performed by multilocus sequencing typing. Whole genome sequencing was performed to analyze the genomic characteristics of CRKP without carbapenemase. The 131 strains of CRKP showed resistance to common antibiotics, except for polymyxin B (1.6% resistance rate) and tigacycline (8.0% resistance rate). A total of 105 (80.2%) CRKP strains carried the Klebsiella pneumoniae carbapenemase (KPC) resistance gene, 15 (11.4%) strains carried the New Delhi Metallo-β-lactamase (NDM) gene, and 4 (3.1%) isolates carried both KPC and NDM genes. Sequence typing (ST) 11 (74.0%) was the dominant sequence type. High detection rates for mrkD (96.2%), fimH (98.5%), entB (100%), and other virulence genes were reported. One hypervirulent CRKP strain was detected. The seven strains of CRKP that did not produce carbapenemase were shown to carry ESBL or AmpC genes and had anomalies in membrane porins OMPK35 and OMPK36, according to whole genome sequencing. In a large-scale tertiary-care general hospital, CRKP mainly carries the KPC gene, has a high drug resistance rate to a variety of antibiotics, and possesses multiple virulence genes. Attention should be paid to CRKP strains with high virulence.

Comprehensive analysis of multiple cytokines to stratify uropathogenic Escherichia coli pathogenesis in mouse model of urinary tract infection

PurposeUrinary tract infection (UTI) is one of the most common human bacterial infections primarily caused by uropathogenic E. coli (UPEC). Empiric treatment in UTI cause emergence of multidrug resistance and limit treatment options. Understanding UTI at the molecular level with respect to the causative pathogen as well as subsequent host response pose an absolute necessity towards appropriate clinical management. This study aimed to investigate host cytokine response in mouse UTI model with respect to bacterial colonization and associated virulence gene expression upon infection. MethodMouse UTI model was established with two clinical UPEC isolates E. coli NP105 and E. coli P025. UPEC colonization in bladder and kidney was evaluated by bacterial culture (CFU/ml). Histopathology of the tissues were examined by hematoxylin and eosin staining. PCR and real time PCR were used to detect the incidence and expression of respective bacterial genes. Cytokine concentrations in tissues and sera were evaluated using ELISA. GraphPad prism version 8.0.2 was used for statistical interpretation. ResultHighest bacterial colonization was observed on 7th and 9th day post infection (p.i). in bladder and kidney of mouse infected with E. coli P025 and E. coli NP105 respectively with a distinct difference in relative expression of fimH and papC adhesin genes in vivo. IL-1β level in tissues and sera of E. coli NP105 and E. coli P025 infected mouse was significantly different but the IL-17A, GCSF, TGF-β levels were comparable. ConclusionThese findings show a role of IL1β to stratify pathogenicity of UPEC in mouse UTI model.

Comparison of virulence factors between ESBL and non-ESBL producing Klebsiella pneumoniae isolates.

Klebsiella pneumoniae is an opportunistic pathogen responsible for causing nosocomial and community-acquired infections. Its pathogenicity is associated with a variety of virulence factors and antibiotic resistance. The aim of the present study was to compare virulence attributes between ESBL and non-ESBL producing isolates. A total of 113 K. pneumoniae including 56 ESBL and 57 non ESBL-producers were collected in Bushehr province, Iran, from November 2017 to February 2019. Enzymatic profile, hypermucoviscosity and biofilm formation were investigated phenotypically. In addition, the presence of rmpA, aerobactin, kfu, allS, mrkD, ybtS, entB, iutA, fimH, wabG, wcaG, K1 and K2 genes were detected by PCR and sequencing. There was no statistically significant difference in enzymatic profile between ESBL and non-ESBL producers. The prevalence of the hypermocoviscosity was lower among ESBL compared to non-ESBL producers but the intensity of biofilm was higher in the ESBL producers. Among the virulence genes, K1, rmpA, iutA, and aero were observed only in non-ESBLs. Moreover, the carriage of allS, K, K2, rmpA, iutA and aero genes was higher in hypermucoviscous in comparison with non hypermucoviscous isolates. The identification of potentially pathogenic isolates plays an important role in preventing their spread as well as the success of their treatment.

Investigation of antibiotic resistance, virulence genes, and biofilm formation of Escherichia coli isolated from sheep feces in Shiraz industrial slaughterhouse, South of Iran.

With the increase in human population, the consumption of livestock products such as sheep meat has also increased. Sheep are the reservoir and shedder of Escherichia coli that can be transmitted to humans. Aims: Characterization of fecal E. coli isolated from sheep in slaughterhouse. Stool specimens were collected from 30 apparently healthy sheep from different flocks in Shiraz industrial slaughterhouse. The resistance of E. coli isolates against 10 antibiotics was determined by disk diffusion method. The presence of three major extended spectrum beta-lactamase (ESBL) genes and five tetracycline resistance genes as well as seven virulence genes were investigated by polymerase chain reaction (PCR) technique. Using the microtiter plate method, the biofilm formation ability of E. coli isolates was investigated. The highest frequency of resistance was to amoxicillin (100%) followed by tetracycline (25%). All E. coli isolates were susceptible to gentamicin and nitrofurantoin, and only one isolate was resistant to the tested third-generation cephalosporins. Multidrug resistance phenotype was observed in 16.7% of the isolates. bla TEM (25%) was the most prevalent ESBL gene and tetA (62.5%) was the most prevalent tetracycline resistance gene in the isolates. crl, csgA, fimH, and bcsA genes were present in all isolates, and the prevalence of papC and afa genes was 95.8% and 83.3%, respectively. In total, 62.5% of the isolates were biofilm producers. According to the concept of One Health, the presence of virulent antibiotic-resistant biofilm producing strains of E. coli in sheep is a risk to public health.

Prevalence and molecular screening of some virulence genes among Klebsiella species isolated from Camels

Klebsiella species is a bacterial organism responsible for serious infections in both animals and people. This study try to spot highlights on the predominance of Klebsiella species among camels as well as screening of some virulence genes. For this purpose, 345 camel samples were taken, including 160 nasal swabs from camels with respiratory distress, off-feeding, or fever., severe nasal discharge, and depression, as well as organ samples (lung (90), trachea (40), intestine (30), and liver (25), were collected from east west coast border in Egypt. The results reported that Klebsiella species was isolated with 36.8% (127/345). By PCR iutA, fimH, and traT genes were detected in all strains with 100% and mrkA gene with 85 %. In conclusion, Klebsiella species is an important circulating pathogen among camel populations and carried several virulence genes that have a critical role in their pathogenicity and strict control measures should be applied to prevent serious infections and complications.

Study of some virulence genes from uropathogenic Klebsiella pneumoniae and Pseudomonas aeruginosa isolated in Wasit Province, Iraq

Abstract Background: Klebsiella pneumoniae and Pseudomonas aeruginosa are the most common causes of nosocomial urinary tract infections (UTIs), and in recent years, these bacteria have become significantly more resistant to antibiotics. Objective: The objective of the study was to determine the frequency of uropathogenic K. pneumoniae and P. aeruginosa in clinical urine samples from patients with UTIs in Wasit Province. Materials and Methods: Initially, 100 clinical urine samples were taken for this investigation from (October 1 to December 1, 2022), and the isolates were initially identified using culture, microscopic analysis, and biochemical assays. Results: The findings of the biochemical results revealed that 16/100 isolates had a 16% positive response for K. pneumonia, and 13/100 isolates had a 13% positive response for P. aeruginosa. When DNA was recovered from the isolates, the nucleic acid purity was diverse from 1.8 to 2.0, and the concentration fluctuated from 50 to 360 mg/µL. By using molecular techniques, including the 16S rRNA gene, for confirmation of the diagnosis. These findings were validated by the polymerase chain reaction method used to detect the virulence genes fimH gene, where 4/16 (25%) and mrkA gene, where result 7/16 (43.75%) were positive in recovered K. pneumoniae isolated. And RNA polymerase subunit B (rpoB) gene where results 10/13 (76.92%) were positive in recovered P. aeruginosa isolated. Conclusion: In conclusion, the outcomes of this study presented a significant increase in biofilm-forming and multidrug-resistant K. pneumoniae isolates, which also harbor a wide range of virulence genes and used rpoB as high molecular identification properties to confirm the P. aeruginosa, the most efficient antibiotics for its treatment were Impinem and Nitrofurantoin for both K. pneumonia and P. aeruginosa.

The Molecular Detection and Antimicrobial Profiles of Selected Bacterial Pathogens in Slaughterhouses in Riyadh City, Saudi Arabia

Inadequate hygienic conditions and poor handling are the primary causes of contamination in abattoirs. This study aimed to identify and molecularly detect pathogenic bacteria in sheep meat at slaughterhouses in Riyadh City, Saudi Arabia. Additionally, the study evaluated the sensitivity of these bacteria to various antimicrobials. In total, 150 samples were collected three times every two months from November 2021 to March 2022 from four abattoirs located in the south, west, east, and north of Riyadh. Pathogenic bacteria were separated using selective media, and the Vitek 2 system was utilized to identify all species and test their response to antibiotics. PCR was employed to detect virulence genes. The four pathogenic bacteria identified in all samples were Escherichia coli (12%), Klebsiella pneumoniae (9.3%), Salmonella enterica (7.3%), and Pseudomonas aeruginosa (6.6%). Abattoir D had a high number of bacteria isolated in January. K. pneumoniae and S. enterica exhibited resistance to ampicillin. S. enterica also demonstrated resistance to gentamicin, ciprofloxacin, and trimethoprim/sulfamethoxazole. P. aeruginosa was resistant to tigecycline. PCR results indicated positive tests for the E. coli gene FimH, the P. aeruginosa genes plcH and toxA, and the K. pneumoniae gene mrkD. Pathogenic bacteria with positive results for virulence genes have the potential to cause contamination and human diseases. To improve quality and reduce contamination, the government must address the issue of providing adequate and safe water for activities in all abattoirs in Riyadh City.