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1.
Funct Integr Genomics ; 24(5): 154, 2024 Sep 03.
Article de Anglais | MEDLINE | ID: mdl-39223360

RÉSUMÉ

Proteus mirabilis is a gram-negative pathogen that caused significant opportunistic infections. In this study we aimed to identify antimicrobial resistance (AMR) genes and virulence determinants in two pan-drug resistant isolate "Bacteria_11" and "Bacteria_27" using whole genome sequencing. Proteus mirabilis "Bacteria_11" and "Bacteria_27" were isolated from two different hospitalized patients in Egypt. Antimicrobial susceptibility determined using Vitek 2 system, then whole genome sequencing (WGS) using MinION nanopore sequencing was done. Antimicrobial resistant genes and virulence determinants were identified using ResFinder, CADR AMR database, Abricate tool and VF analyzer were used respectively. Multiple sequence alignment was performed using MAFFT and FastTree, respectively. All genes were present within bacterial chromosome and no plasmid was detected. "Bacteria_11" and "Bacteria_27" had sizes of approximately 4,128,657 bp and 4,120,646 bp respectively, with GC content of 39.15% and 39.09%. "Bacteria_11" and "Bacteria_27" harbored 43 and 42 antimicrobial resistance genes respectively with different resistance mechanisms, and up to 55 and 59 virulence genes respectively. Different resistance mechanisms were identified: antibiotic inactivation, antibiotic efflux, antibiotic target replacement, and antibiotic target change. We identified several genes associated with aminoglycoside resistance, sulfonamide resistance. trimethoprim resistance tetracycline resistance proteins. Also, those responsible for chloramphenicol resistance. For beta-lactam resistance, only blaVEB and blaCMY-2 genes were detected. Genome analysis revealed several virulence factors contribution in isolates pathogenicity and bacterial adaptation. As well as numerous typical secretion systems (TSSs) were present in the two isolates, including T6SS and T3SS. Whole genome sequencing of both isolates identify their genetic context of antimicrobial resistant genes and virulence determinants. This genomic analysis offers detailed representation of resistant mechanisms. Also, it clarifies P. mirabilis ability to acquire resistance and highlights the emergence of extensive drug resistant (XDR) and pan-drug resistant (PDR) strains. This may help in choosing the most appropriate antibiotic treatment and limiting broad spectrum antibiotic use.


Sujet(s)
Multirésistance bactérienne aux médicaments , Proteus mirabilis , Facteurs de virulence , Proteus mirabilis/génétique , Proteus mirabilis/pathogénicité , Proteus mirabilis/effets des médicaments et des substances chimiques , Proteus mirabilis/isolement et purification , Multirésistance bactérienne aux médicaments/génétique , Facteurs de virulence/génétique , Génome bactérien , Humains , Antibactériens/pharmacologie , Séquençage du génome entier , Virulence/génétique , Tests de sensibilité microbienne , Infections à Proteus/microbiologie , Infections à Proteus/traitement médicamenteux
2.
J Microbiol Methods ; 224: 107008, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-39103095

RÉSUMÉ

Proteus mirabilis is a predominant species in cases of food poisoning associated with meat products and is also an opportunistic pathogen causing numerous infections in humans. This study aimed to differentiate P. mirabilis isolates using intergenic region polymorphism analysis (IRPA). The IRPA typing scheme was developed to amplify polymorphic fragments in intergenic regions (IGRs). The presence, absence, or size change of amplified products were identified and utilized as genetic markers for rapid differentiation of strains. A total of 75 P. mirabilis isolates were isolated from 63 fresh poultry and pork samples were subtyped using the IRPA and ERIC-PCR methods, and their antibiotic resistance profiles were tested. The majority of P. mirabilis isolates showed resistance to tetracycline (85.3%), doxycycline (93.3%), chloramphenicol (82.7%), streptomycin (92.0%), spectinomycin (80.0%), trimethoprim (97.3%); trimethoprim-sulfalleth (82.7%), and erythromycin (100.0%). In contrast, resistance rates to ceftriaxon, cefoxitin, cefepime, and cefotaxim were lower at only 17.3%, 5.3%, 6.7%, and 13.3%, respectively, among P. mirabilis isolates. Eleven loci were selected for analysis of the genetic diversity of 75 P. mirabilis isolates. A combination of 4 loci was determined as the optimal combination. The results compared to those obtained using ERIC-PCR for the same isolates. The Simpson's index of diversity was 0.999 for IRPA and 0.923 for ERIC-PCR, indicating that IRPA has a higher discriminatory power than ERIC-PCR. The concordance between IRPA and ERIC-PCR methods was low, primarily because IRPA classified isolates from the same ERIC cluster into separate clusters due to its high resolution. The IRPA method presented in this study offers a rapid, simple, reproducible, and economical approach for genotyping P. mirabilis.


Sujet(s)
Antibactériens , ADN intergénique , Réaction de polymérisation en chaîne , Proteus mirabilis , Proteus mirabilis/génétique , Proteus mirabilis/effets des médicaments et des substances chimiques , Proteus mirabilis/isolement et purification , Réaction de polymérisation en chaîne/méthodes , Animaux , Antibactériens/pharmacologie , ADN intergénique/génétique , Suidae , Polymorphisme génétique , Volaille/microbiologie , Techniques de génotypage/méthodes , Génotype , Tests de sensibilité microbienne , ADN bactérien/génétique , Infections à Proteus/microbiologie , Résistance bactérienne aux médicaments/génétique , Techniques de typage bactérien/méthodes
3.
World J Urol ; 42(1): 469, 2024 Aug 07.
Article de Anglais | MEDLINE | ID: mdl-39110241

RÉSUMÉ

PURPOSE: About 50% of individuals with long-term indwelling catheters are affected by catheter encrustations and bladder stone formation. Therefore, prophylaxis of catheter encrustations is important. Currently, however, neither an established prophylaxis nor a standardized in-vitro model to test different measures exist. We have therefore developed and qualitatively evaluated an in-vitro model of catheter encrustation. METHODS: Size 14 French suprapubic catheters were incubated under sterile conditions at 37 degrees Celsius in five different media: (1) sterile artificial urine (n = 16), (2) artificial urine with E. coli (n = 8), (3) with Pseudomonas aeruginosa (n = 8), (4) with Proteus mirabilis (n = 8), and (5) with a mix of these three strains (n = 8). Catheter balloons were inflated either a glycerine or a bactericidal solution. After 6 weeks, the catheters were removed from the solution, dried, and weighed, and a photometric determination of the retrieved encrustations was performed. RESULTS: Most frequently and pronounced encrustations were detected in the Pseudomonas group. The median weight of these encrustations (50% struvite and brushite) was 84.4 mg (47.7 mg / 127.3 mg). Even on catheters stored in sterile urine, encrustations (69.2% struvite) were found. Bacterial growth was not affected by the medium used for catheter blockage. CONCLUSION: Although in-vitro models appear to be limited because they lack "the human factor", they are valuable for systematically assessing physico-chemical factors affecting encrustations. Therefore, our model, being reliable and cost-effective, may foster further research despite its limitations.


Sujet(s)
Cathéters urinaires , Humains , Cathéters urinaires/microbiologie , Cathéters urinaires/effets indésirables , Cathéters à demeure/microbiologie , Cathéters à demeure/effets indésirables , Proteus mirabilis/isolement et purification , Pseudomonas aeruginosa , Techniques in vitro , Infections sur cathéters/prévention et contrôle , Infections sur cathéters/microbiologie , Escherichia coli , Cathétérisme urinaire/effets indésirables , Cathétérisme urinaire/instrumentation , Modèles biologiques
4.
J Investig Med High Impact Case Rep ; 12: 23247096241274340, 2024.
Article de Anglais | MEDLINE | ID: mdl-39180447

RÉSUMÉ

Proteus mirabilis is a very common gram-negative facultative anaerobe seen in urinary tract infections. This rod-shaped bacterium tends to cause urolithiasis via its ability to alkalinize the urine. However, in some cases, this bacterium has been shown to cause bacteremia as well as other complicated infections. Here we would like to present a rare case of Proteus mirabilis that has invaded the brain in a patient that has a ventriculoperitoneal (VP) shunt placed due to coccidioidal meningitis causing hydrocephalus. We would also like to discuss the importance of the monitoring of VP shunt and discuss their likelihood of infections and the medical as well as surgical management.


Sujet(s)
Abcès cérébral , Coccidioïdomycose , Hydrocéphalie , Infections à Proteus , Proteus mirabilis , Dérivation ventriculopéritonéale , Humains , Abcès cérébral/microbiologie , Hydrocéphalie/chirurgie , Coccidioïdomycose/complications , Coccidioïdomycose/diagnostic , Proteus mirabilis/isolement et purification , Dérivation ventriculopéritonéale/effets indésirables , Infections à Proteus/complications , Infections à Proteus/microbiologie , Mâle , Tomodensitométrie , Antibactériens/usage thérapeutique , Imagerie par résonance magnétique
5.
BMC Microbiol ; 24(1): 216, 2024 Jun 19.
Article de Anglais | MEDLINE | ID: mdl-38890647

RÉSUMÉ

OBJECTIVE: This study aims to conduct an in-depth genomic analysis of a carbapenem-resistant Proteus mirabilis strain to uncover the distribution and mechanisms of its resistance genes. METHODS: The research primarily utilized whole-genome sequencing to analyze the genome of the Proteus mirabilis strain. Additionally, antibiotic susceptibility tests were conducted to evaluate the strain's sensitivity to various antibiotics, and related case information was collected to analyze the clinical distribution characteristics of the resistant strain. RESULTS: Study on bacterial strain WF3430 from a tetanus and pneumonia patient reveals resistance to multiple antibiotics due to extensive use. Whole-genome sequencing exposes a 4,045,480 bp chromosome carrying 29 antibiotic resistance genes. Two multidrug-resistant (MDR) gene regions, resembling Tn6577 and Tn6589, were identified (MDR Region 1: 64.83 Kb, MDR Region 2: 85.64 Kbp). These regions, consist of integrative and conjugative elements (ICE) structures, highlight the intricate multidrug resistance in clinical settings. CONCLUSION: This study found that a CR-PMI strain exhibits a unique mechanism for acquiring antimicrobial resistance genes, such as blaNDM-1, located on the chromosome instead of plasmids. According to the results, there is increasing complexity in the mechanisms of horizontal transmission of resistance, necessitating a comprehensive understanding and implementation of targeted control measures in both hospital and community settings.


Sujet(s)
Antibactériens , Protéines bactériennes , Multirésistance bactérienne aux médicaments , Tests de sensibilité microbienne , Infections à Proteus , Proteus mirabilis , Séquençage du génome entier , bêta-Lactamases , Proteus mirabilis/génétique , Proteus mirabilis/effets des médicaments et des substances chimiques , Proteus mirabilis/enzymologie , Proteus mirabilis/isolement et purification , bêta-Lactamases/génétique , Humains , Multirésistance bactérienne aux médicaments/génétique , Antibactériens/pharmacologie , Infections à Proteus/microbiologie , Protéines bactériennes/génétique , Chromosomes de bactérie/génétique , Génome bactérien/génétique , Carbapénèmes/pharmacologie
6.
Pak J Biol Sci ; 27(5): 268-275, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-38840467

RÉSUMÉ

<b>Background and Objective:</b> Urinary tract infections from the use of an indwelling urinary catheter are one of the most common infections caused by <i>Proteus mirabilis</i>. Due to their biofilm-producing capacity and the increasing antimicrobial resistance in this microorganism, this study aimed to determine the prevalence, biofilm-producing capacity, antimicrobial resistance patterns, multidrug resistance and plasmid mediated resistance of the recovered isolates. <b>Materials and Methods:</b> A total of 50 urinary samples were collected from May to August, 2018 from patients on indwelling urinary catheters. Using routine microbiological and biochemical methods, 37 <i>P. mirabilis</i> were isolated. Biofilm forming capability was determined among the isolates using the tube method while antimicrobial susceptibility and plasmid curing were also performed. <b>Results:</b> All isolates were biofilm producers with 17(46%) being moderate producers while 20(54%) were strong biofilm formers. The study isolates exhibited a high resistance rate to empiric antibiotics, including ceftazidime (75.8%), cefuroxime (54.5%), ampicillin (69.7%) and amoxicillin-clavulanic acid (51.5%). Low resistance was seen in the fluoroquinolones, gentamicin and nitrofurantoin. Plasmid curing experiment revealed that most isolates lost their resistance indicating that resistance was borne on plasmids. Plasmid carriage is likely the reason for the high MDR rate of 56.8% observed. <b>Conclusion:</b> These findings necessitate the provision of infection control programs which will guide and implement policies.


Sujet(s)
Antibactériens , Biofilms , Cathéters à demeure , Tests de sensibilité microbienne , Proteus mirabilis , Biofilms/effets des médicaments et des substances chimiques , Biofilms/croissance et développement , Proteus mirabilis/effets des médicaments et des substances chimiques , Proteus mirabilis/génétique , Proteus mirabilis/isolement et purification , Cathéters à demeure/microbiologie , Cathéters à demeure/effets indésirables , Humains , Antibactériens/pharmacologie , Antibactériens/usage thérapeutique , Infections urinaires/microbiologie , Infections urinaires/traitement médicamenteux , Infections urinaires/diagnostic , Plasmides/génétique , Cathéters urinaires/microbiologie , Cathéters urinaires/effets indésirables , Résistance bactérienne aux médicaments , Infections à Proteus/microbiologie , Infections à Proteus/traitement médicamenteux , Infections sur cathéters/microbiologie , Infections sur cathéters/diagnostic , Infections sur cathéters/traitement médicamenteux , Femelle , Mâle , Multirésistance bactérienne aux médicaments/génétique
7.
Ann Clin Microbiol Antimicrob ; 23(1): 46, 2024 May 24.
Article de Anglais | MEDLINE | ID: mdl-38790053

RÉSUMÉ

BACKGROUND: Proteus mirabilis is an opportunistic pathogen that has been held responsible for numerous nosocomial and community-acquired infections which are difficult to be controlled because of its diverse antimicrobial resistance mechanisms. METHODS: Antimicrobial susceptibility patterns of P. mirabilis isolates collected from different clinical sources in Mansoura University Hospitals, Egypt was determined. Moreover, the underlying resistance mechanisms and genetic relatedness between isolates were investigated. RESULTS: Antimicrobial susceptibility testing indicated elevated levels of resistance to different classes of antimicrobials among the tested P. mirabilis clinical isolates (n = 66). ERIC-PCR showed great diversity among the tested isolates. Six isolates (9.1%) were XDR while all the remaining isolates were MDR. ESBLs and AmpCs were detected in 57.6% and 21.2% of the isolates, respectively, where blaTEM, blaSHV, blaCTX-M, blaCIT-M and blaAmpC were detected. Carbapenemases and MBLs were detected in 10.6 and 9.1% of the isolates, respectively, where blaOXA-48 and blaNDM-1 genes were detected. Quinolone resistant isolates (75.8%) harbored acc(6')-Ib-cr, qnrD, qnrA, and qnrS genes. Resistance to aminoglycosides, trimethoprim-sulfamethoxazole and chloramphenicol exceeded 80%. Fosfomycin was the most active drug against the tested isolates as only 22.7% were resistant. Class I or II integrons were detected in 86.4% of the isolates. Among class I integron positive isolates, four different gene cassette arrays (dfrA17- aadA5, aadB-aadA2, aadA2-lnuF, and dfrA14-arr-3-blaOXA-10-aadA15) and two gene cassettes (dfrA7 and aadA1) were detected. While class II integron positive isolates carried four different gene cassette arrays (dfrA1-sat1-aadA1, estXVr-sat2-aadA1, lnuF- dfrA1-aadA1, and dfrA1-sat2). CONCLUSION: P. Mirabilis ability to acquire resistance determinants via integrons may be held responsible for the elevated rates of antimicrobial resistance and emergence of XDR or even PDR strains limiting the available therapeutic options for management of infections caused by those strains.


Sujet(s)
Antibactériens , Multirésistance bactérienne aux médicaments , Tests de sensibilité microbienne , Infections à Proteus , Proteus mirabilis , Égypte/épidémiologie , Humains , Proteus mirabilis/génétique , Proteus mirabilis/effets des médicaments et des substances chimiques , Proteus mirabilis/isolement et purification , Multirésistance bactérienne aux médicaments/génétique , Infections à Proteus/microbiologie , Infections à Proteus/épidémiologie , Antibactériens/pharmacologie , Prévalence , bêta-Lactamases/génétique , Intégrons/génétique , Protéines bactériennes/génétique , Infection croisée/microbiologie , Infection croisée/épidémiologie , Mâle
8.
Emerg Microbes Infect ; 13(1): 2353310, 2024 Dec.
Article de Anglais | MEDLINE | ID: mdl-38712879

RÉSUMÉ

OXA-48-like enzymes represent the most frequently detected carbapenemases in Enterobacterales in Western Europe, North Africa and the Middle East. In contrast to other species, the presence of OXA-48-like in Proteus mirabilis leads to an unusually susceptible phenotype with low MICs for carbapenems and piperacillin-tazobactam, which is easily missed in the diagnostic laboratory. So far, there is little data available on the genetic environments of the corresponding genes, blaOXA-48-like, in P. mirabilis. In this study susceptibility phenotypes and genomic data of 13 OXA-48-like-producing P. mirabilis were investigated (OXA-48, n = 9; OXA-181, n = 3; OXA-162, n = 1). Ten isolates were susceptible to meropenem and ertapenem and three isolates were susceptible to piperacillin-tazobactam. The gene blaOXA-48 was chromosomally located in 7/9 isolates. Thereof, in three isolates blaOXA-48 was inserted into a P. mirabilis genomic island. Of the three isolates harbouring blaOXA-181 one was located on an IncX3 plasmid and two were located on a novel MOBF plasmid, pOXA-P12, within the new transposon Tn7713. In 5/6 isolates with plasmidic location of blaOXA-48-like, the plasmids could conjugate to E. coli recipients in vitro. Vice versa, blaOXA-48-carrying plasmids could conjugate from other Enterobacterales into a P. mirabilis recipient. These data show a high diversity of blaOXA-48-like genetic environments compared to other Enterobacterales, where genetic environments are quite homogenous. Given the difficult-to-detect phenotype of OXA-48-like-producing P. mirabilis and the location of blaOXA-48-like on mobile genetic elements, it is likely that OXA-48-like-producing P. mirabilis can disseminate, escape most surveillance systems, and contribute to a hidden spread of OXA-48-like.


Sujet(s)
Antibactériens , Protéines bactériennes , Tests de sensibilité microbienne , Infections à Proteus , Proteus mirabilis , bêta-Lactamases , Proteus mirabilis/génétique , Proteus mirabilis/enzymologie , Proteus mirabilis/isolement et purification , Proteus mirabilis/effets des médicaments et des substances chimiques , bêta-Lactamases/génétique , bêta-Lactamases/métabolisme , Protéines bactériennes/génétique , Protéines bactériennes/métabolisme , Antibactériens/pharmacologie , Humains , Infections à Proteus/microbiologie , Plasmides/génétique , Ilots génomiques , Carbapénèmes/pharmacologie
9.
Braz J Microbiol ; 55(2): 1231-1241, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38727921

RÉSUMÉ

Laccase is an exothermic enzyme with copper in its structure and has an important role in biodegradation by providing oxidation of phenolic compounds and aromatic amines and decomposing lignin. The aim of this study is to reach maximum laccase enzyme activity with minimum cost and energy through optimization studies of Proteusmirabilis isolated from treatment sludge of a textile factory. In order to increase the laccase enzyme activities of the isolates, medium and culture conditions were optimized with the study of carbon (Glucose, Fructose, Sodium Acetate, Carboxymethylcellulose, Xylose) and nitrogen sources (Potassium nitrate, Yeast Extract, Peptone From Soybean, Bacteriological Peptone), incubation time, pH, temperature and Copper(II) sulfate concentration then according to the results obtained. Response Surface Method (RSM) was performed on six different variables with three level. According to the data obtained from the RSM, the maximum laccase enzyme activity is reached at pH 7.77, temperature 30.03oC, 0.5 g/L CuSO4, 0.5 g/L fructose and 0.082 g/L yeast extract conditions. After all, the laccase activity increased 2.7 times. As a result, laccase activity of P. mirabilis can be increased by optimization studies. The information obtained as a result of the literature studies is that the laccase enzymes produced in laboratory and industrial scale are costly and their amounts are low. This study is important in terms of obtaining more laccase activity from P.mirabilis with less cost and energy.


Sujet(s)
Milieux de culture , Laccase , Proteus mirabilis , Eaux d'égout , Température , Industrie textile , Laccase/métabolisme , Proteus mirabilis/enzymologie , Proteus mirabilis/isolement et purification , Proteus mirabilis/métabolisme , Proteus mirabilis/génétique , Eaux d'égout/microbiologie , Concentration en ions d'hydrogène , Milieux de culture/composition chimique , Déchets industriels , Azote/métabolisme , Carbone/métabolisme , Dépollution biologique de l'environnement
10.
Diagn Microbiol Infect Dis ; 109(2): 116286, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38574445

RÉSUMÉ

BACKGROUND: Although Proteus species are occasional causes of serious infections, their epidemiology has not been well defined. The objective was to describe the overall and species-specific occurrence and determinants of Proteus species bloodstream infection (BSI) in a large Australian population. METHODS: All Queensland residents with Proteus species BSI identified within the publicly funded healthcare system between 2000 and 2019 were included. RESULTS: A total of 2,143 incident episodes of Proteus species BSI were identified among 2,079 Queensland residents. The prevalence of comorbid illness differed with higher Charlson comorbidity scores observed with P. penneri and P. vulgaris, and higher prevalence of liver disease with P. penneri, higher comorbid cancer with P. vulgaris, and lower diabetes and renal disease prevalence with P. mirabilis BSIs. CONCLUSION: This study provides novel information on the epidemiology of Proteus species BSI.


Sujet(s)
Bactériémie , Infections à Proteus , Proteus , Humains , Bactériémie/épidémiologie , Bactériémie/microbiologie , Mâle , Adulte d'âge moyen , Femelle , Infections à Proteus/épidémiologie , Infections à Proteus/microbiologie , Sujet âgé , Queensland/épidémiologie , Proteus/classification , Proteus/isolement et purification , Prévalence , Adulte , Comorbidité , Sujet âgé de 80 ans ou plus , Jeune adulte , Proteus mirabilis/isolement et purification , Proteus mirabilis/classification
11.
J Infect Chemother ; 30(9): 881-886, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-38442770

RÉSUMÉ

INTRODUCTION: Carbon dioxide-dependent Proteus mirabilis has been isolated from clinical specimens. It is not clear whether mutations in carbonic anhydrase are responsible for the carbon dioxide dependence of P. mirabilis. The pathogenicity of carbon dioxide-dependent P. mirabilis also remains unclear. The purpose of this study was to determine the cause carbon dioxide dependence of P. mirabilis and its pathogenicity. METHODS: The DNA sequence of can encoding carbonic anhydrase of a carbon dioxide-dependent P. mirabilis small colony variant (SCV) isolate was analyzed. To confirm that impaired carbonic anhydrase activity is responsible for the formation of the carbon dioxide-dependent SCV phenotype of P. mirabilis, we performed complementation experiments using plasmids with intact can. Additionally, mouse infection experiments were performed to confirm the change in virulence due to the mutation of carbonic anhydrase. RESULTS: We found that the can gene of the carbon dioxide-dependent P. mirabilis SCV isolate showed had a frameshift mutation with a deletion of 1 bp (c. 173delC). The can of P. mirabilis encodes carbonic anhydrase was also found to function in Escherichia coli. The cause of the carbon dioxide-dependent SCV phenotype of P. mirabilis was an abnormality in carbonic anhydrase. Nevertheless, no changes were observed in virulence due to the mutation of carbonic anhydrase in mouse infection experiments. CONCLUSIONS: The can gene is essential for the growth of P. mirabilis in ambient air. The mechanisms underlying this fitness advantage in terms of infection warrant further investigation.


Sujet(s)
Dioxyde de carbone , Carbonic anhydrases , Infections à Proteus , Proteus mirabilis , Proteus mirabilis/génétique , Proteus mirabilis/pathogénicité , Proteus mirabilis/isolement et purification , Dioxyde de carbone/métabolisme , Animaux , Souris , Infections à Proteus/microbiologie , Carbonic anhydrases/génétique , Carbonic anhydrases/métabolisme , Humains , Virulence/génétique , Femelle , Mutation avec décalage du cadre de lecture
12.
Arch Razi Inst ; 77(3): 1257-1260, 2022 06.
Article de Anglais | MEDLINE | ID: mdl-36618312

RÉSUMÉ

Proteus mirabilis is considered one of the causative pathogens that leads to complicated urinary tract infection (UTI); moreover, it produces urease. Urease plays a key role as a virulence factor for P. mirabilis. UreR, a member of the AraC/XylS family of transcriptional regulators, positively activates the expression of the ure gene cluster in the presence of urea. Therefore, this study was designed to investigate the contribution of ureR to urease activity and virulence in urinary tract infections. A total of 74 clinical samples were collected from August to December 2020. The urine samples were taken from individuals with parasitic infections in their urinary tracts. After cultivating the samples on the MacConkey agar, the initial identification was performed based on traditional methods with the automated VITEK-2 compact method. Bacterial isolates were inoculated by stabbing and streaking into a slant of urease agar, which were then incubated at 37°C for 24-48 h. The polymerase chain reaction technique was used to detect the P. mirabilis ureR gene. The results of biochemical studies were utilized to confirm the identification of P. mirabilis isolates that had previously been made. All isolates had the same oxidase-negative, catalase-positive, oxidase-negative, and catalase-positive properties. They were motile, methyl red, and uric acid, catalase, citrate, and urease positive. The results of investigating the expression of the ureR gene in 15 isolates of P. mirabilis suggested that only 14 (93.3%) of the isolates produced ureR gene products using unique primers.


Sujet(s)
Protéines bactériennes , Proteus mirabilis , Urease , Infections urinaires , Agar-agar , Protéines bactériennes/génétique , Protéines bactériennes/métabolisme , Catalase/métabolisme , Iraq , Proteus mirabilis/génétique , Proteus mirabilis/isolement et purification , Urease/génétique , Urease/métabolisme , Infections urinaires/microbiologie , Humains
13.
J Laryngol Otol ; 136(3): 219-222, 2022 Mar.
Article de Anglais | MEDLINE | ID: mdl-34702380

RÉSUMÉ

OBJECTIVE: Microbial infection plays an important role in exacerbation of chronic otitis media. The aim of this study was to analyse the microbiota in chronic otitis media in the context of local treatment. METHOD: In this prospective study, samples for microbiological examination were taken from 119 patients who underwent operation because of chronic otitis media. RESULTS: The results were compared between groups depending on the type of operation (none, tympanoplasty or radical), the presence of cholesteatoma or granulomatous tissue or discharge from the ear as a symptom of exacerbation. Antibiotic susceptibility of germs was analysed to define the strategy of treatment. A total of 209 samples were collected from 119 patients with chronic otitis media. CONCLUSION: Pseudomonas aeruginosa and Staphylococcus aureus were pathogens most frequently identified from the ear in the course of chronic otitis media. Pseudomonas aeruginosa was concerned with major pathology of the middle ear (radical surgery, cholesteatoma or granulomatous tissue, persisting discharge after treatment), whereas Staphylococcus aureus was obtained in dry perforations without other pathology in the middle-ear cavity. Ciprofloxacin was effective against Staphylococcus aureus, but Pseudomonas aeruginosa strains were ciprofloxacin resistant.


Sujet(s)
Antibactériens/usage thérapeutique , Ciprofloxacine/usage thérapeutique , Otite moyenne/traitement médicamenteux , Otite moyenne/microbiologie , Pseudomonas aeruginosa/isolement et purification , Staphylococcus aureus/isolement et purification , Adolescent , Adulte , Sujet âgé , Maladie chronique , Escherichia coli/isolement et purification , Femelle , Humains , Mâle , Adulte d'âge moyen , Pologne , Études prospectives , Proteus mirabilis/isolement et purification , Jeune adulte
14.
Microbiologyopen ; 10(6): e1244, 2021 11.
Article de Anglais | MEDLINE | ID: mdl-34964289

RÉSUMÉ

The human microbiome has begun to emerge as a potential forensic tool, with varied applications ranging from unique identification to investigative leads that link individuals and/or locations. The relative abundance of the combined DNA of the microbiome, compared to human nuclear DNA, may expand potential sources of biological evidence, especially in cases with transfer or low-copy number DNA samples. This work sought to determine the optimal swab type for the collection and analysis of microorganisms. A bacterium (Proteus mirabilis) was deposited by pipette onto four swab types (cotton, flocked, dental applicators, and dissolvable), and extraction and real-time PCR quantitation of the bacterial DNA were performed, which allowed for absolute microbial DNA recovery and comparison of yields across the four sampling substrates. Flocked swabs had the highest yield (~1240 ng) compared to the cotton swabs (~184 ng), dental applicators (~533 ng), and dissolvable swabs (~430 ng). The collection efficiency was further evaluated for cotton and flocked swabs using dried microbial samples spotted onto non-porous surfaces (treated wood, glass, plastic, and tile). Flocked swabs performed consistently better across wood, glass, and tile, but showed decreased recovery from plastic. The cotton swabs failed in the recovery of P. mirabilis DNA across all surfaces. Knowing the appropriate sampling substrate will be useful as others continue to investigate the use of the microbiome as a forensics tool.


Sujet(s)
Techniques bactériologiques/instrumentation , ADN bactérien/analyse , Microbiote , Proteus mirabilis/isolement et purification , Manipulation d'échantillons/instrumentation , ADN bactérien/isolement et purification , Humains , Proteus mirabilis/génétique , Réaction de polymérisation en chaine en temps réel
15.
Int J Mol Sci ; 22(9)2021 Apr 29.
Article de Anglais | MEDLINE | ID: mdl-33946710

RÉSUMÉ

Considering the advent of antibiotic resistance, the study of bacterial metabolic behavior stimulated by novel antimicrobial agents becomes a relevant tool to elucidate involved adaptive pathways. Profiling of volatile metabolites was performed to monitor alterations of bacterial metabolism induced by biosynthesized silver nanoparticles (bio-AgNPs). Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae and Proteus mirabilis were isolated from pressure ulcers, and their cultures were prepared in the presence/absence of bio-AgNPs at 12.5, 25 and 50 µg mL-1. Headspace solid phase microextraction associated to gas chromatography-mass spectrometry was the employed analytical platform. At the lower concentration level, the agent promoted positive modulation of products of fermentation routes and bioactive volatiles, indicating an attempt of bacteria to adapt to an ongoing suppression of cellular respiration. Augmented response of aldehydes and other possible products of lipid oxidative cleavage was noticed for increasing levels of bio-AgNPs. The greatest concentration of agent caused a reduction of 44 to 80% in the variety of compounds found in the control samples. Pathway analysis indicated overall inhibition of amino acids and fatty acids routes. The present assessment may provide a deeper understanding of molecular mechanisms of bio-AgNPs and how the metabolic response of bacteria is untangled.


Sujet(s)
Bactéries/effets des médicaments et des substances chimiques , Bactéries/métabolisme , Nanoparticules métalliques/usage thérapeutique , Escarre/traitement médicamenteux , Escarre/microbiologie , Argent/usage thérapeutique , Composés organiques volatils/métabolisme , Antibactériens/usage thérapeutique , Bactéries/isolement et purification , Résistance bactérienne aux médicaments , Enterococcus faecalis/effets des médicaments et des substances chimiques , Enterococcus faecalis/isolement et purification , Enterococcus faecalis/métabolisme , Escherichia coli/effets des médicaments et des substances chimiques , Escherichia coli/isolement et purification , Escherichia coli/métabolisme , Humains , Techniques in vitro , Klebsiella pneumoniae/effets des médicaments et des substances chimiques , Klebsiella pneumoniae/isolement et purification , Klebsiella pneumoniae/métabolisme , Voies et réseaux métaboliques/effets des médicaments et des substances chimiques , Métabolome/effets des médicaments et des substances chimiques , Métabolomique , Tests de sensibilité microbienne , Proteus mirabilis/effets des médicaments et des substances chimiques , Proteus mirabilis/isolement et purification , Proteus mirabilis/métabolisme , Composés organiques volatils/composition chimique , Composés organiques volatils/classification
16.
Braz J Microbiol ; 52(2): 927-937, 2021 Jun.
Article de Anglais | MEDLINE | ID: mdl-33826115

RÉSUMÉ

Antibiotic resistance is a main threat to the public health. It is established that the overuse and misuse of antibiotics are highly contributing to antibiotic resistance. However, the impact of nonantibiotic antimicrobial agents like biocides on antibiotic resistance is currently investigated and studied. Triclosan (TCS) is a broad-spectrum antibacterial agent widely used as antiseptic and disinfectant. In this study, we aimed to evaluate the effect of exposure of Proteus mirabilis clinical isolates to sublethal concentrations of TCS on their antibiotic susceptibility, membrane characteristics, efflux activity, morphology, and lipid profile. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of TCS were determined for 31 P. mirabilis clinical isolates. The tested isolates were adapted to increasing sublethal concentrations of TCS. The MICs of 16 antibiotics were determined before and after adaptation. Membrane characteristics, efflux activity, ultrastructure, and lipid profile of the tested isolates were examined before and after adaptation. Most adapted P. mirabilis isolates showed increased antibiotic resistance, lower membrane integrity, lower outer and inner membrane permeability, and higher membrane depolarization. Nonsignificant change in membrane potential and lipid profile was found in adapted cells. Various morphological changes and enhanced efflux activity was noticed after adaptation. The findings of the current study suggest that the extensive usage of TCS at sublethal concentrations could contribute to the emergence of antibiotic resistance in P. mirabilis clinical isolates. TCS could induce changes in the bacterial membrane properties and increase the efflux activity and in turn decrease its susceptibility to antibiotics which would represent a public health risk.


Sujet(s)
Adaptation physiologique , Anti-infectieux locaux/métabolisme , Proteus mirabilis/physiologie , Triclosan/métabolisme , Anti-infectieux locaux/pharmacologie , Transport biologique/effets des médicaments et des substances chimiques , Membrane cellulaire/effets des médicaments et des substances chimiques , Membrane cellulaire/métabolisme , Résistance bactérienne aux médicaments , Égypte , Hôpitaux universitaires , Humains , Tests de sensibilité microbienne , Infections à Proteus/microbiologie , Proteus mirabilis/effets des médicaments et des substances chimiques , Proteus mirabilis/isolement et purification , Proteus mirabilis/métabolisme , Triclosan/pharmacologie
17.
Ann Emerg Med ; 78(3): 357-369, 2021 09.
Article de Anglais | MEDLINE | ID: mdl-33781606

RÉSUMÉ

STUDY OBJECTIVE: Third-generation cephalosporin-resistant (3GCR) Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis (EKP) are an increasingly common cause of community-onset urinary tract infections (UTIs) in the United States. The 3GCR antimicrobial resistance pattern in these Enterobacterales species is most commonly due to production of extended-spectrum ß-lactamases. We sought to provide contemporary, emergency department (ED)-focused data on 3GCR-EKP UTI regional prevalence, presentation, antibiotic susceptibility, and empiric treatment patterns, and outcomes. METHODS: We performed a retrospective cohort study of all adults admitted with a febrile UTI at 21 Kaiser Permanente Northern California EDs between January 2017 and June 2019. Inclusion criteria included fever; admitting diagnosis of UTI, pyelonephritis, or sepsis; and ED urine culture with greater than 100,000 colony-forming units/mL of an EKP species. 3GCR was defined as in vitro resistance to ceftriaxone, ceftazidime, or both. 3GCR-EKP cases were compared with non-3GCR-EKP controls for the following: demographics, comorbidities, presenting clinical features, urinary isolate antimicrobial susceptibility, treatment, and clinical outcomes. The primary outcome measure was the rate of discordant initial empiric antibiotic treatment (administered within 6 hours of ED arrival) when compared with antimicrobial susceptibility testing. Secondary outcomes included hospital length of stay and 90-day mortality, adjusted for comorbidities and severity of illness. RESULTS: There were 4,107 patients (median age 73 years and 35% men) who met study inclusion criteria. Of these patients, 530 (12.9%) had a 3GCR-EKP urinary tract infection. The proportion of subjects possessing risk factors for a health care-associated or extended-spectrum ß-lactamase infection was 92.8% of case patients and 86.1% of controls. When comparing 3GCR-EKP case and non-3GCR-EKP control isolates, ciprofloxacin susceptibility rates were 21% versus 88%, and piperacillin/tazobactam susceptibility rates were 89% versus 97%, respectively. Initial empiric antibiotic therapy was discordant with antimicrobial susceptibility testing results in 63% of case patients versus 7% of controls (odds ratio 21.0; 95% confidence interval 16.9 to 26.0). The hospital length of stay was longer for 3GCR-EKP case patients, with an adjusted mean difference of 29.7 hours (95% CI 19.0 to 40.4). Ninety-day mortality was 12% in case patients versus 8% in controls (adjusted odds ratio 1.56; 95% confidence interval 1.07 to 2.28). CONCLUSION: In this large, 2017 to 2019 Northern California ED study, nearly 13% of febrile EKP UTIs requiring hospitalization were caused by 3GCR-EKP, and in these cases, initial empiric therapy was often discordant with antimicrobial susceptibility testing. 3GCR-EKP infections were associated with a longer hospital length of stay and higher 90-day mortality. Similar data from other regions and for outpatient UTIs are needed.


Sujet(s)
Résistance aux céphalosporines/effets des médicaments et des substances chimiques , Céphalosporines/usage thérapeutique , Service hospitalier d'urgences/statistiques et données numériques , Infections urinaires/traitement médicamenteux , Sujet âgé , Sujet âgé de 80 ans ou plus , Études cas-témoins , Escherichia coli/isolement et purification , Femelle , Humains , Klebsiella pneumoniae/isolement et purification , Durée du séjour/statistiques et données numériques , Mâle , Adulte d'âge moyen , Proteus mirabilis/isolement et purification , Études rétrospectives , Infections urinaires/épidémiologie , Infections urinaires/microbiologie
18.
BMC Pregnancy Childbirth ; 21(1): 159, 2021 Feb 23.
Article de Anglais | MEDLINE | ID: mdl-33622283

RÉSUMÉ

BACKGROUND: Urinary tract infections (UTIs) in pregnant women contribute about 25% of all infections and are among the most frequent clinical bacterial infections. Pregnancy changes in women that include anatomical, physiological and hormonal make them susceptible to develop UTI. Left untreated, UTI in pregnancy is associated with grave complications to the mother and fetus. These complications can be decreased by prompt and proper diagnosis and appropriate treatment that also reduces the emergency of drug resistance. Antimicrobial resistance is a major health problem in the treatment of UTI. We determined the prevalence, bacteriology and antimicrobial susceptibility of symptomatic urinary tract infection among pregnant women at Mbarara Regional Referral Hospital. METHODS: We conducted a cross-sectional study from November 2019 to February 2020 involving 400 pregnant women with symptomatic UTI. Patient information was obtained using a structured questionnaire. We collected clean-catch midstream urine specimens for culture and performed antimicrobial susceptibility testing following Clinical and Laboratory Standards Institute standards. Data was entered into RED-cap Version 8.2 software and then exported to Stata Version 14.1 for analysis. RESULTS: The proportion of culture-positive UTI was 140/400 (35%). Gram-negative bacteria were more prevalent (73%): Klebsiella pneumoniae 52(37.41%), Escherichia coli 40(28.78%), Pseudomonas aeruginosa and Proteus mirabilis 7(5.04% each), Citrobacter freundii 1(1%). Staphylococcus aureus 33(23.57%) was the only gram-positive isolate. All the isolates were resistant to ampicillin, amoxicillin, amoxicillin/clavulanic acid and ceftazidime/clavulanic acid (95.7, 95.0, 72.9 and 50.7% respectively). Prevalence of extended-spectrum beta-lactamases producing Enterobacteriaceae was 29.0% while that of methicillin-resistant Staphylococcus aureus was 33.3%. All cultures demonstrated resistance to more than one drug. Majority of the bacterial isolates were sensitive to ciprofloxacin, ceftriaxone, nitrofurantoin, cefotaxime and gentamicin at 82.9, 81.4, 79.3, 78.6, 66.4 and 65.7% respectively. CONCLUSIONS: Klebsiella pneumoniae was the most prevalent isolate followed by E. coli. These two organisms were highly resistant to the commonly used antibiotics. Our study recorded a higher prevalence of culture-positive UTI in pregnancy than all the studies in Uganda. Empirical treatment of UTI should be minimized as sensitivity varies for each organism, for each drug and over time.


Sujet(s)
Bactériurie/épidémiologie , Escherichia coli/isolement et purification , Klebsiella pneumoniae/isolement et purification , Complications infectieuses de la grossesse/épidémiologie , Infections urinaires/épidémiologie , Adulte , Bactériurie/microbiologie , Études transversales , Femelle , Humains , Grossesse , Complications infectieuses de la grossesse/microbiologie , Prévalence , Proteus mirabilis/isolement et purification , Pseudomonas aeruginosa/isolement et purification , Ouganda , Infections urinaires/microbiologie , Jeune adulte
19.
Food Microbiol ; 96: 103724, 2021 Jun.
Article de Anglais | MEDLINE | ID: mdl-33494897

RÉSUMÉ

Proteus mirabilis is an important pathogen involved in human urinary tract infections, and also more isolated from stools of patients with diarrheal disease than from healthy patients. The role of food, especially poultry products as source for human infection and multi-resistant strains remains unclear. As a resident in broilers' intestines, P. mirabilis can contaminate broiler carcasses due to slaughter practices, and be a risk for human infection. The present study evaluated the performance of five isolation media, and subsequently examined the presence of P. mirabilis on broiler carcasses at retail. Additionally, isolates were characterized by the Dienes' test, repetitive element PCR fingerprinting and pulsed-field gel electrophoresis, and their antibiotic resistance profile determined. Using a combined isolation protocol on blood agar, xylose lysine deoxycholate agar and violet red bile glucose agar, P. mirabilis was isolated from 29 out of 80 broiler carcasses (36.25%) with a mean contamination level of 2.25 ± 0.50 log10 CFU/g. A high strain heterogeneity was present in isolates from broilers and human stool. The same strains were not shared, but the antibiotic resistance profiling was similar. A role of poultry products as source for human infection should be taken into account.


Sujet(s)
Antibactériens/pharmacologie , Résistance bactérienne aux médicaments , Fèces/microbiologie , Viande/microbiologie , Maladies de la volaille/microbiologie , Infections à Proteus/microbiologie , Infections à Proteus/médecine vétérinaire , Proteus mirabilis/isolement et purification , Animaux , Belgique , Poulets , Humains , Proteus mirabilis/classification , Proteus mirabilis/effets des médicaments et des substances chimiques , Proteus mirabilis/génétique
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