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1.
Arab J Chem ; 16(7): 104813, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36969951

RESUMO

The recent pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has opened the door to potential threats of the respiratory system. The discovery of drugs from natural sources is one of the most important strategies for treating the upper respiratory tract. In this study, we investigated the selected formulated EOs activities against Gram-negative (E. coli, K. pneumonia, and P. aeruginosa) and Gram-positive (S. aureus, E. fecalis) bacteria and against the SARS-CoV-2 virus, with the mode of action investigated as anti-SARS-CoV-2. Cinnamomum zeylanicum and Syzygium aromaticum EOs were the most promising antibacterial oils. C. zeylanicum EO showed MIC values of 1, 1, 2, ≤0.5, and 8 µg/mL against E. coli, K. pneumoniae, P. aeruginosa, S. aureus, and E. fecalis, respectively, while S. aromaticum EO showed MIC values of 8, 4, 32, 8, 32 µg/mL against the same organisms. The cytotoxic activity of the oil samples was tested in VERO-E6 cells using (MTT) assay and showed that the safest oil was F. vulgare, then L. nobilis, C. carvi, S. aromaticum, and E. globulus. The most potent antiviral EOs were C. zeylanicum oil and S. aromaticum, with IC50 value of 15.16 and 96.5 µg/mL, respectively. Moreover, the safety index of S. aromaticum EO (26.3) was greater than the oil of C. zeylanicum (7.25). The mechanism by which C. zeylanicum oil exerts its antiviral activity may involve both the virucidal effect and its impact on viral reproduction. The nano-emulsion dosage form of the potent EOs was prepared and re-examined against the same bacterial and viral strains. Finally, the chemical characterization of these promising essential oils was analyzed and identified using the GC-MS approach. To the best of our knowledge, this is the first report concerning the in vitro investigation of anti-SARS-CoV-2 activity of these selected essential oils, along with a proposed mechanism for the potent oil's activity.

2.
Infect Drug Resist ; 15: 3801-3814, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35875614

RESUMO

Background and Aims: Reports examine quinolone resistance mechanisms among Pseudomonas spp. are sporadic in the Kingdom of Saudi Arabia (KSA). We previously examined the genetic bases of plasmid-mediated quinolone resistance among Pseudomonas spp. clinical isolates. This study investigated chromosomally mediated quinolone resistance mechanisms via investigation of the mutations in the gyrA and parC genes. Methods: The minimum inhibitory concentration (MIC) to different quinolones was determined. Twenty-nine quinolone resistant Pseudomonas spp. clinical isolates were included. The gyrA and parC genes were sequenced by Sanger capillary electrophoresis. Multiple sequence alignment for the translated gyrA and parC genes was performed to identify mutation sites. Results: Of the 29 isolates, 27 isolates were P. aeruginosa and two were P. putida. The cluster analysis of the quinolone susceptibility pattern revealed seven susceptibility phenotypes (A-G) based on susceptibility patterns rather than the MIC values. Also, 22 different susceptibility phenotypes were detected based on MIC values. All isolates exhibited a missense mutation at position 83 (S83I/T/F) of the gyrA gene in addition to six missense mutations at positions outside the QRDR of this gene. In addition, 82.8% (24/29) of the isolates harbored a missense mutation in the parC gene at position 87 (S87L), along with six novel mutations outside the QRDR of the parC gene. Haplotyping of the gyrA, parC, and the overall QRDR revealed six, 10, and 13 different haplotypes, respectively. Conclusion: This study documents the incidence of the commonly reported mutations in the gyrA and parC genes in addition to novel mutations in these genes among Pseudomonas spp. clinical isolates recovered from KSA. Together with our previous findings, these data provide an insight into the genetic background of quinolone resistance among Pseudomonas spp. clinical isolates in KSA.

3.
Infect Drug Resist ; 14: 4739-4756, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34795490

RESUMO

BACKGROUND: Acinetobacter baumannii (A. baumannii) is one of the most important nosocomial pathogens responsible for a wide range of infections. AIM: This study aimed to investigate the existence of the plasmidic genes encoding for aminoglycoside modifying enzymes (AMEs), 16S rRNA methyltransferases (RMT), and the altered dihydropetroate synthase (DHPS) encoded by the sul1 gene among A. baumannii clinical isolates collected from Taif, Kingdom of Saudi Arabia (KSA). The mutations in aac(6')-Ib and sul1 genes were also investigated. METHODS: Forty A. baumannii clinical isolates were investigated for their susceptibility to ten antibiotics. The plasmid DNA was extracted and screened for nine genes encoding for aminoglycoside resistance in addition to the sul1 gene. The clonal relatedness was determined by random amplified polymorphic DNA (RAPD)-PCR. Mutation in aac(6')-Ib and the sul1 genes were detected by capillary electrophoresis sequencing (CES). RESULTS: All isolates were A. baumannii in which 42.5% of them exhibited a high level of aminoglycoside resistance (HLAR). The most prevalent AMEs and RMT encoding genes were aph(3')-VI, the two aac(6') gene variants [aac(6')-Ib and aac(6')-SL], ant(3'')-I, and armA in which 90%, 87.5%, 85%, and 45% of isolates tested positive, respectively. The other investigated aminoglycoside resistant encoding genes, namely aac(3)-II, aac(6')-II, and rmtB, were not detected. Only 15% of isolates harbored the sul1 gene. RAPD-PCR classified the 40 isolates into three clusters in which cluster II was the main cluster. DNA sequencing revealed that 34.29% (12/35) of isolates tested positive for aac(6')-Ib were found to harbor a common missense mutation in position 102 indicating a novel allelic variant named aac(6')-SL. Also, DNA sequencing revealed three missense mutations in the sul1 gene. CONCLUSION: This is the first Saudi study to investigate the plasmid borne aminoglycoside and sulfonamide resistance genes among A. baumannii clinical isolates. A novel allelic variant for aac(6')-Ib was detected in addition to novel mutations in the sul1 gene.

4.
Infect Drug Resist ; 14: 2003-2014, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34103947

RESUMO

Despite the wide medical knowledge about the direct role of many viruses in the pathogenesis of certain cancers, there is still ambiguity and hazy vision about the direct role of bacteria in cancer incidence. Understanding the role of bacteria in carcinogenesis is no longer a scientific luxury, but it has become an urgent and extremely important necessity to realize the pathogenesis of cancer caused by oncogenic bacteria as an attempt to overcome the oncogenic mechanisms exhibited by these oncogenic bacteria. This review shed the light on the indirect role of the host's inflammatory and immunological responses in the pathogenesis of bacteria-induced cancer. Also, this review discussed the indirect role of the bacterial toxins and virulence factors in the induction of common gastrointestinal cancers, such as gallbladder cancer (GBC), colorectal cancer (CRC), and gastric cancer (GC). Finally, this review dealt with the debate about the possibility of bacterial DNA integration into the human genome and cancer incidence.

5.
Res Rep Trop Med ; 11: 73-80, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33117051

RESUMO

Schistosomiasis ranks second behind malaria in terms of overall morbidity and mortality. We evaluated the lethal effect of Punica granatum ellagitannins, extracted from the fruit rind, placenta and barks of the root and stem, on adult worms of Schistosoma mansoni (S. mansoni). All four ellagitannins were lethal to S. mansoni adult worms. However, while the rind ellagitannins were the most potent, placental ellagitannins were the least. Rind ellagitannins were capable of killing 40% of adult worms at a concentration of 25µg/mL after 5 days. The killing of 100% of the worms was achievable by rind ellagitannins at a concentration of 50µg/mL after 5 days. The LD50S of the rind ellagitannins after 96h and 120h were 41.25 µg/mL and 28.73 respectively. Ellagitannins-treated worms suffered from erosions, wrinkles, swellings and losses, degenerations of the surface tubercles and tegument. In addition, ellagitannins induced deformation and degradation of oral and ventral suckers and degenerations in the muscles of worms. Ellagitannins also caused a separation of coupled worms and reduction of their motility. Data obtained suggest that ellagitannins of pomegranate could be considered as a cheap candidate for the treatment of schistosomiasis.

6.
Infect Drug Resist ; 13: 1237-1250, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32425561

RESUMO

BACKGROUND AND OBJECTIVE: The emergence of carbapenem-resistant K. pneumoniae (CRKP) continues to escalate and is alarming because of the emergence of pan drug-resistant strains. The objective of this study was to investigate the existence of 12 carbapenemase genes among CRKP clinical isolates. METHODS: Ninety-six Klebsiella spp. clinical isolates were collected. The isolates were identified phenotypically and genotypically. These isolates were screened for susceptibility to 24 different antibiotics. The modified Hodge test (MHT) and the Carba Nordmann/Poirel (NP) test were used to phenotypically screen carbapenem-resistant strains for carbapenemase production. Phenotypic characterization of carbapenemases was performed using the combined disk synergy test (CDST). Additionally, the presence of 12 carbapenemase genes in CRKP isolates was investigated. The DNA sequence of bla NDM and bla GES genes was determined. The BOX-PCR technique was used to determine the clonal relationship between CRKP isolates. RESULTS: All carbapenem-resistant isolates were related to K. pneumoniae. Susceptibility testing showed that 19.79% (19/96) of the collected isolates were carbapenem-resistant. Of the CRKP isolates, 68.42% (13/19) tested positive for the MHT and Carba NP test. CDST showed that 42.11% (8/19), 63.16% (12/19), 47.37% (9/19), and 73.68% (14/19) of the CRKP isolates tested positive for the inhibitory effect of clavulanic acid, sulbactam, phenylboronic acid, and tazobactam, respectively, while 84.21% (16/19) and 68.42% (13/16) tested positive for the inhibitory effect of EDTA and mercaptopropionic acid, respectively. It was found that 10.53% (2/19) of the isolates tested positive for the inhibitory effect of sodium chloride. Molecular investigation of carbapenemases showed that 26.32% (5/19), 73.68% (14/19), 21.05% (4/19), 10.53% (2/19), and 5.26% (1/19) of the isolates tested positive for bla NDM, bla OXA-48, bla OXA-181, bla OXA-51, and bla OXA-23, respectively. None of the isolates tested positive for bla OXA-40 and bla OXA-58. Two allelic variants of bla NDM (bla NDM-1 and bla NDM-25) were detected. BOX-PCR revealed high clonal relatedness between CRKP isolates. CONCLUSION: MHT was more sensitive than Carba NP test for evaluating carbapenemase production and class D carbapenemase genes were the most prevalent of the 12 carbapenemase genes that were evaluated.

7.
Infect Drug Resist ; 12: 3113-3124, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31632100

RESUMO

BACKGROUND AND OBJECTIVE: Acinetobacter baumannii (A. baumannii) is a common nosocomial pathogen, which developed multi-drug-resistance to different classes of antibiotics including carbapenems. This study examined ten common carbapenemase genes among 32 carbapenem-resistant A. baumannii clinical isolates recovered from Taif, Saudi Arabia. METHODS: Isolates were phenotypically identified to the genus level by Vitek®2 and API 20NE®. The species level was confirmed by the amplification of bla OXA-51. The susceptibility for 21 different antibiotics was performed by Vitek 2 and modified Kirby-Bauer method. Isolates were genetically screened for 10 carbapenemases. Phylogenetic relatedness between isolates was determined by ERIC-PCR. RESULTS: Genotypically identified A. baumannii represented 100% of the total phenotypically identified Acinetobacter spp. All the carbapenem-resistant isolates were sensitive to polymyxin B and colistin. Among the other antibiotics, ampicillin/sulbactam and tigecycline were the most effective agents. 90.8% of the isolates were resistant to all ten investigated ß-lactams. bla OXA-51, bla IPM, bla NDM and bla OXA-23 were detected in 100%, 87.5%, 62.5% and 59.4% of isolates, respectively. Also, bla VIM and bla OXA-40 were less prevalent and were detected in 9.3% and 3.1% of the isolates, respectively. In addition, bla KPC, bla OXA-48, bla OXA-58, bla OXA-181 were not detected in any isolate. The A. baumannii isolates were categorised into ten genotypes on the basis of the detected carbapenemase genes and ERIC-PCR revealed a remarkable clonal diversity among these isolates. CONCLUSION: Class A and class D carbapenemase genes were the most commonly detected among carbapenem resistant A. baumannii (CRAB) clinical isolates.

8.
Int J Nanomedicine ; 14: 2515-2531, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31040672

RESUMO

BACKGROUND: Fungal keratitis (FK) is a serious pathogenic condition usually associated with significant ocular morbidity. Natamycin (NAT) is the first-line and only medication approved by the Food and Drug Administration for the treatment of FK. However, NAT suffers from poor corneal penetration, which limits its efficacy for treating deep keratitis. PURPOSE: The objective of this work was to prepare NAT solid lipid nanoparticles (NAT-SLNs) to achieve sustained drug release and increased corneal penetration. METHODS: NAT-SLNs were prepared using the emulsification-ultrasonication technique. Box- Behnken experimental design was applied to optimize the effects of independent processing variables (lipid concentration [X1], surfactant concentration [X2], and sonication frequency [X3]) on particle size (R1), zeta potential (ZP; R2), and drug entrapment efficiency (EE%) (R3) as responses. Drug release profile, ex vivo corneal permeation, antifungal susceptibility, and cytotoxicity of the optimized formula were evaluated. RESULTS: The optimized formula had a mean particle size of 42 r.nm (radius in nanometers), ZP of 26 mV, and EE% reached ~85%. NAT-SLNs showed an extended drug release profile of 10 hours, with enhanced corneal permeation in which the apparent permeability coefficient (Papp) and steady-state flux (Jss) reached 11.59×10-2 cm h-1 and 3.94 mol h-1, respectively, in comparison with 7.28×10-2 cm h-1 and 2.48 mol h-1 for the unformulated drug, respectively. Antifungal activity was significantly improved, as indicated by increases in the inhibition zone of 8 and 6 mm against Aspergillus fumigatus ATCC 1022 and a Candida albicans clinical isolate, respectively, and minimum inhibitory concentration values that were decreased 2.5-times against both of these pathogenic strains. NAT-SLNs were found to be non-irritating to corneal tissue. NAT-SLNs had a prolonged drug release rate, that improved corneal penetration, and increased antifungal activity without cytotoxic effects on corneal tissues. CONCLUSION: Thus, NAT-SLNs represent a promising ocular delivery system for treatment of deep corneal keratitis.


Assuntos
Córnea/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Infecções Oculares Fúngicas/tratamento farmacológico , Ceratite/tratamento farmacológico , Lipídeos/química , Nanopartículas/química , Natamicina/administração & dosagem , Natamicina/uso terapêutico , Administração Oftálmica , Análise de Variância , Animais , Antifúngicos/farmacologia , Preparações de Ação Retardada/uso terapêutico , Portadores de Fármacos/uso terapêutico , Liberação Controlada de Fármacos , Fungos/efeitos dos fármacos , Cabras , Humanos , Ceratite/microbiologia , Testes de Sensibilidade Microbiana , Natamicina/farmacologia , Tamanho da Partícula , Permeabilidade , Eletricidade Estática
9.
Infect Drug Resist ; 12: 915-923, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31118699

RESUMO

Background: Quinolones are among the most effective antibiotics against Pseudomonas spp. Several chromosomal and/or plasmid-mediated quinolone-resistance mechanisms have been found in Pseudomonas.  Plasmid-mediated quinolone-resistance (PMQR) is mediated by quinolone-resistance (QNR) proteins, modifying enzymes or efflux pumps. Only a few previous studies examined the prevalence of quinolone-resistance in the Kingdom of Saudi Arabia (KSA) and showed it is increasing. Mechanisms of quinolone-resistance among Pseudomonas spp. in the KSA; examined herein; have not been extensively studied. Methods: Ninety-two Pseudomonas isolates were collected and their resistance to seven different types of quinolones was determined by the microbroth dilution method. PMQR mechanisms were examined using a PCR screen to identify six PMQR genes including qnrA, qnrB, qnrD, qnrS, aac(6´)-Ib-cr, and qepA. Clonal relatedness of the quinolone-resistant isolates was determined by ERIC-PCR. Results: Of the isolates, 42.4% (39/92) were resistant to 1-7 of the tested quinolones. Gemifloxacin resistance was the lowest (28.3%) while resistance to the other six quinolones were ≥ 35%. The most common biotype among the 39 quinolone-resistant isolates was resistance to the seven tested quinolones (26/39; 66.7%). qnrD, qnrS, and aac(6´)-Ib-cr were found in 31 (79.5%), 31 (79.5%) and 28 (71.8%) of the 39 isolates, respectively, and all three genes together were found in 22 of the 39 isolates (56.4%). qnrA, qnrB, and qepA were not detected in any of the isolates and two isolates did not harbor any of the six tested genes. The isolates showed 38 different ERIC profiles and only two isolates (Pa16 and Pa17) had an identical profile. Conclusion: This is the first description of PMQR mechanisms among clinical Pseudomonas isolates from the KSA, which appears to be mainly mediated by qnrD, qnrS, and aac(6´)-Ib-cr.

10.
Bioorg Med Chem ; 27(7): 1263-1273, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30777662

RESUMO

A general strategy towards total synthesis of (-)-codonopsinine, (-)-codonopsine and codonopsinine analogues has been developed from (D)-tartaric acid via the intermediate (3S,4R)-1-methyl-2-oxo-5-(2,2,2-trichloroacetamido)pyrrolidinediacetate (7). α-amidoalkylation studies of 7 with electron rich benzene derivative 8a-g as C-nucleophiles afforded (aryl derivatives) 9a-g. The target compounds 1, 2 and 13c-g were readily obtained from 10a-gvia Grignard addition to the homochiral lactam which was produced by deoxygenation using Lewis-acid followed by deacetylation. The synthesized compounds were loaded onto solid lipid nanoparticle formulations (SLNs) prepared by hot emulsification-ultrasonication technique using Compritol as solid lipid and Pluronic f68 as surfactant. SLNs were fully evaluated and the permeation of synthesized compound from SLNs was assayed against non-formulated compounds through dialysis membranes using Franz cell. The data indicated good physical characteristics of the prepared SLNs, sustaining of release profiles and significant improvement of permeation ability when compared to the non-formulated compounds. The antibacterial and antifungal activities of 1, 2 and 13c-g were determined by disc diffusion and microbroth dilution method to determine the minimum inhibitory concentrations (MIC) against seven microorganisms (Staphyloccus aureus, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Acinetobacter baumannii and Candida albicans). The most active compounds against the Gram positive S. aureus were 1, 13C, 13d, and 13g. Also, 13c, 13d, and 13e had antibacterial activity but not 13f against some Gram negative organisms (E. coli, and P. mirabilis). MIC concentrations against P. aeruginosa, and K. pneumoniae were ≥512 µg/ml, while that against A. baumannii was ≥128 µg/ml except for nanoformulae of 13e and 13f that were 16 and 64 µg/ml, respectively. No antifungal activity against Candida albicans was recorded for all compounds and their nanoformulae (MIC > 1024 µg/ml). SLNs were found to decrease the MIC values for some of the compounds with no effect on the antifungal activity. In conclusion, we demonstrated a novel, straight-forward and economical procedure for the total synthesis of (-)-codonopsinine 1, (-)-codonopsine 2 and codonopsinine analogues 13c-g from simple and commercially available starting materials; d-tartaric acid; with antimicrobial activities against Gram positive and Gram-negative organisms that were improved by SLNs formulations.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Lipídeos/química , Nanopartículas/química , Pirrolidinas/farmacologia , Alquilação , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Bactérias/efeitos dos fármacos , Relação Dose-Resposta a Droga , Composição de Medicamentos , Desenho de Fármacos , Fungos/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Pirrolidinas/síntese química , Pirrolidinas/química , Estereoisomerismo , Relação Estrutura-Atividade
11.
J Basic Microbiol ; 58(9): 720-729, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29962068

RESUMO

Frankia strains isolated from Saudi Arabia, reported for the first time, were identified based on the morphological and molecular tools compared to those isolated from Egypt. All strains displayed typical morphological characterization of Frankia strains represented by branched hyphae, production of vesicles and sporangia. The phylogenetic analysis and relationships among Frankia strains were investigated by comparing 16S rRNA gene sequences. The analysis revealed three genetic groups which formed two clusters. The first cluster was composed of eight Frankia strains subdivided into two genetic groups (one group containing five strains; CgIT3 L2 , CgIS3 N2 , CgIS1 N1, CgIT7N2, and G5; the other group included of three strains: CgIT5L3, CgIS1 N2 , and CcI13). The second cluster was composed of only one genetic group of Frankia strain CgIS3 N1 . The strains in each genetic group exhibited similar genetic distances. All Frankia strains were able to reinfect their host of Casuarina species. For ability of these strains to resist heavy metals, our results proved that all Frankia strains isolated can resist Cu, Co, and Zn at low concentration except Pb which exhibit highly toxic effect at the same concentration used. Frankia strain G5 was proved to be the most resistant strain for heavy metals tested.


Assuntos
Farmacorresistência Bacteriana Múltipla , Frankia/classificação , Frankia/efeitos dos fármacos , Metais Pesados/farmacologia , Filogenia , Microbiologia do Solo , Análise por Conglomerados , DNA Bacteriano/genética , Egito , Fagales/microbiologia , Frankia/genética , Frankia/metabolismo , Metais Pesados/metabolismo , Nodulação , RNA Ribossômico 16S/genética , Arábia Saudita , Análise de Sequência de DNA
12.
Int J Microbiol ; 2017: 8050432, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28638412

RESUMO

Inappropriate use of antibiotics in clinical settings is thought to have led to the global emergence and spread of multidrug-resistant pathogens. The goal of this study was to investigate the prevalence of genes encoding aminoglycoside resistance and plasmid-mediated quinolone resistance among clinical isolates of Klebsiella pneumoniae. All K. pneumoniae isolates were phenotypically identified using API 20E and then confirmed genotypically through amplification of the specific K. pneumoniae phoE gene. All isolates were genotyped by the enterobacterial repetitive intergenic consensus polymerase chain reaction technique (ERIC-PCR). Antibiotic susceptibility testing was done by a modified Kirby-Bauer method and broth microdilution. All resistant or intermediate-resistant isolates to either gentamicin or amikacin were screened for 7 different genes encoding aminoglycoside-modifying enzymes (AMEs). In addition, all resistant or intermediate-resistant isolates to either ciprofloxacin or levofloxacin were screened for 5 genes encoding the quinolone resistance protein (Qnr), 1 gene encoding quinolone-modifying enzyme, and 3 genes encoding quinolone efflux pumps. Biotyping using API 20E revealed 13 different biotypes. Genotyping demonstrated that all isolates were related to 2 main phylogenetic groups. Susceptibility testing revealed that carbapenems and tigecycline were the most effective agents. Investigation of genes encoding AMEs revealed that acc(6')-Ib was the most prevalent, followed by acc(3')-II, aph(3')-IV, and ant(3'')-I. Examination of genes encoding Qnr proteins demonstrated that qnrB was the most prevalent, followed by qnrS, qnrD, and qnrC. It was found that 61%, 26%, and 12% of quinolone-resistant K. pneumoniae isolates harbored acc(6')-Ib-cr, oqxAB, and qebA, respectively. The current study demonstrated a high prevalence of aminoglycoside and quinolone resistance genes among clinical isolates of K. pneumoniae.

13.
Microb Drug Resist ; 23(6): 703-717, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28099061

RESUMO

The extensive use of ß-lactam antibiotics has led to emergence and spread of extended-spectrum ß-lactamases (ESBLs). This study was conducted to investigate the prevalence of 7 different ESBL genes (blaTEM, blaSHV, blaCTX-M, blaVEB, blaPER, blaGES, and blaOXA-10) and O25b-ST131 high-risk clone among 61 clinical isolates of Escherichia coli. Also, one broad-spectrum ß-lactamase (blaOXA-1) was investigated. This study was also constructed to evaluate iodometric overlay method in detection of ESBL production. Phenotypic identification of E. coli isolates using API 20E revealed 18 distinct biotypes. DNA fingerprinting using enterobacterial repetitive intergenic consensus polymerase chain reaction (ERIC-PCR) differentiated all isolates into 2 main phylogenetic groups with 60 distinct genetic profiles. Elevated values of minimal inhibitory concentration (MIC)50 and MIC90 for third- and fourth-generation cephalosporins were observed. Phenotypic tests revealed that 85.24% of isolates were ESBL producers. The incidence rates of blaTEM, blaSHV, blaCTX-M, blaGES, blaOXA-1, and blaOXA-10 among E. coli ESBL producer phenotype were 69.23%, 25%, 96.15%, 3.85%, 11.54%, and 48%, respectively. On the other hand, blaVEB and blaPER were not detected. Sequencing of blaTEM and blaSHV revealed that blaTEM-214 and blaSHV-11 were the most prevalent variants. Group characterization of blaCTX-M revealed that blaCTX-M-1 was the most prevalent group of blaCTX-M family. It was found that 30.77% of E. coli ESBL producers belonged to O25b-ST131 clone harboring blaCTX-M-15. This study concluded that iodometric overlay method was 100% sensitive in detection of ESBL production. To our knowledge, this is the first Egyptian study that declares the emergence of E. coli O25b-ST131 harboring blaGES.


Assuntos
Proteínas de Escherichia coli/genética , Escherichia coli/genética , beta-Lactamases/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Criança , Pré-Escolar , Egito , Escherichia coli/efeitos dos fármacos , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia , Feminino , Humanos , Lactente , Masculino , Testes de Sensibilidade Microbiana/métodos , Pessoa de Meia-Idade , Filogenia , Reação em Cadeia da Polimerase/métodos , Adulto Jovem , beta-Lactamas/farmacologia
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