scholarly journals A complex mutant of TEM-1 beta-lactamase with mutations encountered in both IRT-4 and extended-spectrum TEM-15, produced by an Escherichia coli clinical isolate.

1997 ◽  
Vol 41 (6) ◽  
pp. 1322-1325 ◽  
Author(s):  
D Sirot ◽  
C Recule ◽  
E B Chaibi ◽  
L Bret ◽  
J Croize ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Amino Acid ◽  
Direct Sequencing ◽  
Hydrolytic Activity ◽  
Beta Lactamase ◽  
E Coli ◽  
Low Level ◽  
Extended Spectrum ◽  
Extended Spectrum Beta Lactamases ◽  
Synergy Test

Escherichia coli GR102 was isolated from feces of a leukemic patient. It expressed different levels of resistance to amoxicillin or ticarcillin plus clavulanate and to the various cephalosporins tested. The double-disk synergy test was weakly positive. Production of a beta-lactamase with a pI of 5.6 was transferred to E. coli HB101 by conjugation. The nucleotide sequence was determined by direct sequencing of the amplification products obtained by PCR performed with TEM gene primers. This enzyme differed from TEM-1 (blaT-1B gene) by four amino acid substitutions: Met-->Leu-69, Glu-->Lys-104, Gly-->Ser-238 and Asn-->Asp-276. The amino acid susbstitutions Leu-69 and Asp-276 are known to be responsible for inhibitor resistance of the IRT-4 mutant, as are Lys-104 and Ser-238 substitutions for hydrolytic activity of the extended-spectrum beta-lactamases TEM-15, TEM-4, and TEM-3. These combined mutations led to a mutant enzyme which conferred a level of resistance to coamoxiclav (MIC, 64 microg/ml) much lower than that conferred by IRT-4 (MIC, 2,048 microg/ml) but higher than that conferred by TEM-15 or TEM-1 (MIC, 16 microg/ml). In addition, the MIC of ceftazidime for E. coli transconjugant GR202 (1 microg/ml) was lower than that for E. coli TEM-15 (16 microg/ml) and higher than that for E. coli IRT-4 or TEM-1 (0.06 microg/ml). The MICs observed for this TEM-type enzyme were related to the kinetic constants Km and k(cat) and the 50% inhibitory concentration, which were intermediate between those observed for IRT-4 and TEM-15. In conclusion, this new type of complex mutant derived from TEM-1 (CMT-1) is able to confer resistance at a very low level to inhibitors and at a low level to extended-spectrum cephalosporins. CMT-1 received the designation TEM-50.

Characterization of two plasmid-encoded cefotaximases found in clinical Escherichia coli isolates: CTX-M-65 and a novel enzyme, CTX-M-87

2009 ◽  
Vol 58 (6) ◽  
pp. 811-815 ◽  
Author(s):  
Jun Yin ◽  
Jun Cheng ◽  
Zhen Sun ◽  
Ying Ye ◽  
Yu-Feng Gao ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Catalytic Activity ◽  
Amino Acid ◽  
Amino Acid Sequence ◽  
Hydrolytic Activity ◽  
E Coli ◽  
High Affinity ◽  
Extended Spectrum ◽  
M 14

Three clinical strains of Escherichia coli (p168, p517 and p667) were collected in 2006 from three hospitals in Anhui Province (China). PCR and DNA sequencing revealed that E. coli p168 carried a novel extended-spectrum β-lactamase (ESBL), which was designated CTX-M-87. The extended-spectrum β-lactamase which was carried by E. coli p517 and E. coli p667 was previously named CTX-M-65. The deduced amino acid sequence of CTX-M-87, with pI 9.1, differed from that of CTX-M-14 by the substitutions Ala77→Val and Pro167→Leu. Like CTX-M-14, CTX-M-87 had a more potent hydrolytic activity against cefotaxime than against ceftazidime and had high affinity for cefuroxime and cefotaxime. These data show that mutations at position 167 in CTX-M do not always affect catalytic activity and substrate preference.

scholarly journals Deteksi Fenotipik Escherichia coli Penghasil Extended Spectrum Beta-lactamases (ESBLs) pada Sampel Makanan di Krian Sidoarjo

Life Science ◽  
2019 ◽  
Vol 8 (1) ◽  
pp. 95-105
Author(s):  
Yulianto Ade Prasetya ◽  
Ike Yuyun Winarsih ◽  
Kharisma Aprilia Pratiwi ◽  
Merinsa Chorry Hartono ◽  
Dita Nur Rochimah
Keyword(s):  
Escherichia Coli ◽  
Methylene Blue ◽  
Food Samples ◽  
Beta Lactamases ◽  
E Coli ◽  
Extended Spectrum ◽  
Confirmation Test ◽  
Extended Spectrum Beta Lactamases ◽  
Fried Foods ◽  
Synergy Test

Escherichia coli is a group of Enterobacteriaceae bacteria that often contaminate food so that it can cause diarrhea. These bacteria are very difficult to treat if they are able to produce the Extended-Spectrum Beta-Lactamases (ESBLs) enzyme. The purpose of this study was to identify ESBLs-producing E. coli in food samples in Krian Sidoarjo. Food samples (fried foods, cilok tempura and chili sauce) were collected from ten different places. The sample was then grown on Eosin Methylene Blue (EMB) medium and purified by the 16 streak method, as well as biochemical character tests. The ESBLs phenotypic E. coli method was carried out by screening test and confirmation test using a Double Disk Synergy Test (DDST). Thirty colonies were able to grow on EMB media, but after microscopic identification and biochemistry testing only four samples were E. coli positive and were able to produce ESBLs from the phenotypic test that had been carried out. ESBLs-producing E. coli testing is important not only for nosocomial infections but also for the community so it needs attention to the spread of ESBLs resistance among microorganism species.   Escherichia coli termasuk kelompok bakteri Enterobacteriaceae yang sering mengkontaminasi makanan sehingga dapat menyebabkan diare. Bakteri ini sangat sulit diobati apabila mampu memproduksi enzim Extended Spectrum Beta-Lactamases (ESBLs). Tujuan penelitian ini adalah untuk mengindetifikasi E. coli penghasil ESBLs pada sampel makanan di Krian Sidoarjo. Sampel makanan (gorengan, cilok, tempura, dan saus sambal) dikumpulkan dari sepuluh tempat berbeda. Sampel kemudian ditumbuhkan pada medium Eosin Metilen Blue (EMB) dan dimurnikan dengan metode streak 16, serta dilakukan karakteristik uji biokimia. Metode fenotipik E. coli penghasil ESBLs dilakukan dengan uji skrining dan uji konfirmasi menggunakan double disk synergy test (DDST). Sebanyak tiga puluh koloni mampu tumbuh pada media EMB, namun setelah diidentifikasi mikroskopis dan uji biokiomia hanya empat sampel positif E. coli dan mampu menghasilkan ESBLs dari uji fenotipik yang telah dilakukan. Pengujian E. coli penghasil ESBLs penting dilakukan bukan hanya pada infeksi nosokomial, tetapi juga pada komunitas sehingga perlu mendapat perhatian terhadap penyebaran resistensi ESBLs diantara spesies mikroorganisme.

scholarly journals TEM-28 from an Escherichia coli clinical isolate is a member of the His-164 family of TEM-1 extended-spectrum beta-lactamases.

1996 ◽  
Vol 40 (1) ◽  
pp. 260-262 ◽  
Author(s):  
P A Bradford ◽  
N V Jacobus ◽  
N Bhachech ◽  
K Bush
Keyword(s):  
Escherichia Coli ◽  
Amino Acid ◽  
Nucleotide Sequence ◽  
Clinical Isolate ◽  
Amino Acid Substitutions ◽  
Beta Lactamase ◽  
Beta Lactamases ◽  
Extended Spectrum ◽  
Extended Spectrum Beta Lactamases

TEM-28 (pI 6.1), expressed by an Escherichia coli clinical isolate, is a novel beta-lactamase which hydrolyzed ceftazidime, cefotaxime, and aztreonam with rates of 25, 1.1, and 5.6, respectively, relative to that for benzylpenicillin (100). The nucleotide sequence of blaTEM-28 differed from that of blaTEM-1 by two base changes, resulting in amino acid substitutions of Arg-164 to His and Glu-240 to Lys.

scholarly journals Molecular characterization of beta-lactamase genes produced by community-acquired uropathogenic Escherichia coli in Nouna

2020 ◽  
Vol 14 (11) ◽  
pp. 1274-1280
Author(s):  
Dramane Kiemde ◽  
Inês Ribeiro ◽  
Soufiane Sanou ◽  
Boubacar Coulibaly ◽  
Ali Sie ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Molecular Characterization ◽  
Bacterial Resistance ◽  
Uropathogenic Escherichia Coli ◽  
Common Mechanism ◽  
Beta Lactamase ◽  
E Coli ◽  
Extended Spectrum Beta Lactamases ◽  
Synergy Test

Introduction: Extended-Spectrum Beta-Lactamases (ESBL) are a common mechanism of bacterial resistance in Enterobacteriaceae. The purpose of this study is to characterize the ESBL genes produced by community-acquired uropathogenic Escherichia coli strains in the Nouna District, in the West-African country, Burkina Faso. Methodology: Samples were collected from non-hospitalized patients who came for consultation at the CMA (Centre Médical avec Antenne chirurgicale) in Nouna and were sent to the laboratory for a urine culture test. The detection of ESBL production by the bacteria was carried out with the double-disc synergy test and the extraction of the ESBL genes with the heat shock method. Molecular characterization of ESBL genes was performed with three sequential multiplex polymerase chain reaction (PCR) assays. Results: One hundred and eighty-two (182) bacteriological cultures were analyzed and 29 E. coli isolated, between 01/07/2017 and 01/07/2018. The ESBL phenotype was found in 13/29 (44.8%). Multiplex PCR yielded many beta-lactamase genes, predominantly blaCTX-M-1,3,15 (12/13; 92.3%) followed by beta-lactamase genes blaOXA-1,4,30 (8/13; 61.5%) and beta-lactamase genes blaTEM-1,2 (7/13; 53.8%). Conclusion: This study showed that the blaCTX-M-1,3,15 genes produced by uropathogenic E. coli were predominant. Sequencing of these genes would be needed to better characterize the different types of ESBL circulating in Nouna.

scholarly journals Multidrug-Resistant, Including Extended-Spectrum Beta Lactamase-Producing and Quinolone-Resistant, Escherichia coli Isolated from Poultry and Domestic Pigs in Dar es Salaam, Tanzania

Antibiotics ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 406
Author(s):  
Zuhura I. Kimera ◽  
Fauster X. Mgaya ◽  
Gerald Misinzo ◽  
Stephen E. Mshana ◽  
Nyambura Moremi ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Multidrug Resistant ◽  
Antibiotics Resistance ◽  
Beta Lactamase ◽  
Domestic Pigs ◽  
Extended Spectrum Beta Lactamase ◽  
Phenotypic Profile ◽  
E Coli ◽  
Extended Spectrum ◽  
Esbl Producers

We determined the phenotypic profile of multidrug-resistant (MDR) Escherichia coli isolated from 698 samples (390 and 308 from poultry and domestic pigs, respectively). In total, 562 Enterobacteria were isolated. About 80.5% of the isolates were E. coli. Occurrence of E. coli was significantly higher among domestic pigs (73.1%) than in poultry (60.5%) (p = 0.000). In both poultry and domestic pigs, E. coli isolates were highly resistant to tetracycline (63.5%), nalidixic acid (53.7%), ampicillin (52.3%), and trimethoprim/sulfamethoxazole (50.9%). About 51.6%, 65.3%, and 53.7% of E. coli were MDR, extended-spectrum beta lactamase-producing enterobacteriaceae (ESBL-PE), and quinolone-resistant, respectively. A total of 68% of the extended-spectrum beta lactamase (ESBL) producers were also resistant to quinolones. For all tested antibiotics, resistance was significantly higher in ESBL-producing and quinolone-resistant isolates than the non-ESBL producers and non-quinolone-resistant E. coli. Eight isolates were resistant to eight classes of antimicrobials. We compared phenotypic with genotypic results of 20 MDR E. coli isolates, ESBL producers, and quinolone-resistant strains and found 80% harbored blaCTX-M, 15% aac(6)-lb-cr, 10% qnrB, and 5% qepA. None harbored TEM, SHV, qnrA, qnrS, qnrC, or qnrD. The observed pattern and level of resistance render this portfolio of antibiotics ineffective for their intended use.

scholarly journals Evaluation of extended spectrum beta lactamase enzymes prevalence in clinical isolates of Escherichia coli

2011 ◽  
Vol 2 (1) ◽  
pp. 8
Author(s):  
Ronak Bakhtiari ◽  
Jalil Fallah Mehrabadi ◽  
Hedroosha Molla Agamirzaei ◽  
Ailar Sabbaghi ◽  
Mohammad Mehdi Soltan Dallal
Keyword(s):  
Escherichia Coli ◽  
Disk Diffusion ◽  
Confirmatory Test ◽  
Diffusion Method ◽  
Multi Drug Resistance ◽  
Beta Lactamase ◽  
Disk Diffusion Method ◽  
Extended Spectrum Beta Lactamase ◽  
E Coli ◽  
Extended Spectrum

Resistance to b-lactam antibiotics by gramnegative bacteria, especially <em>Escherichia coli (E. coli)</em>, is a major public health issue worldwide. The predominant resistance mechanism in gram negative bacteria particularly <em>E. coli </em>is via the production of extended spectrum beta lactamase (ESBLs) enzymes. In recent years, the prevalence of b-lactamase producing organisms is increased and identification of these isolates by using disk diffusion method and no-one else is not satisfactory. So, this investigation focused on evaluating the prevalence of ESBL enzymes by disk diffusion method and confirmatory test (Combined Disk). Five hundred clinical samples were collected and 200 <em>E. coli </em>isolates were detected by standard biochemical tests. To performing initial screening of ESBLs was used from Disk diffusion method on <em>E. coli </em>isolates. A confirmation test (Combined Disk method) was performed on isolates of resistant to cephalosporin's indicators. Up to 70% isolates exhibited the Multi Drug Resistance phenotype. In Disk diffusion method, 128(64%) <em>E. coli </em>isolates which resistant to ceftazidime and cefotaxime while in Combined Disk, among 128 screened isolates, 115 (89.8%) isolates were detected as ESBLs producers. This survey indicate beta lactamase enzymes are playing a significant role in antibiotic resistance and correct detection of them in phenotypic test by using disk diffusion and combined Disk is essential for accurate recognition of ESBLs.

scholarly journals Phylogenetic Grouping and Virulence Potential of Extended-Spectrum-β-Lactamase-Producing Escherichia coli Strains in Cattle

2012 ◽  
Vol 78 (13) ◽  
pp. 4677-4682 ◽  
Author(s):  
Charlotte Valat ◽  
Frédéric Auvray ◽  
Karine Forest ◽  
Véronique Métayer ◽  
Emilie Gay ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Virulence Determinants ◽  
Phylogenetic Groups ◽  
Content Type ◽  
E Coli ◽  
Extended Spectrum ◽  
Specific Distribution ◽  
Extended Spectrum Beta Lactamases ◽  
Phylogenetic Grouping ◽  
Almost All

ABSTRACTIn line with recent reports of extended-spectrum beta-lactamases (ESBLs) inEscherichia coliisolates of highly virulent serotypes, such as O104:H4, we investigated the distribution of phylogroups (A, B1, B2, D) and virulence factor (VF)-encoding genes in 204 ESBL-producingE. coliisolates from diarrheic cattle. ESBL genes, VFs, and phylogroups were identified by PCR and a commercial DNA array (Alere, France). ESBL genes belonged mostly to the CTX-M-1 (65.7%) and CTX-M-9 (27.0%) groups, whereas those of the CTX-M-2 and TEM groups were much less represented (3.9% and 3.4%, respectively). One ESBL isolate wasstx1andeaepositive and belonged to a major enterohemorrhagicE. coli(EHEC) serotype (O111:H8). Two other isolates wereeaepositive butstxnegative; one of these had serotype O26:H11. ESBL isolates belonged mainly to phylogroup A (55.4%) and, to lesser extents, to phylogroups D (25.5%) and B1 (15.6%), whereas B2 strains were quasi-absent (1/204). The number of VFs was significantly higher in phylogroup B1 than in phylogroups A (P= 0.04) and D (P= 0.02). Almost all of the VFs detected were found in CTX-M-1 isolates, whereas only 64.3% and 33.3% of them were found in CTX-M-9 and CTX-M-2 isolates, respectively. These results indicated that the widespread dissemination of theblaCTX-Mgenes within theE. colipopulation from cattle still spared the subpopulation of EHEC/Shiga-toxigenicE. coli(STEC) isolates. In contrast to other reports on non-ESBL-producing isolates from domestic animals, B1 was not the main phylogroup identified. However, B1 was found to be the most virulent phylogroup, suggesting host-specific distribution of virulence determinants among phylogenetic groups.

scholarly journals Extended Spectrum Beta-Lactamase Escherichia coli in River Waters Collected from Two Cities in Ghana, 2018–2020

2021 ◽  
Vol 6 (2) ◽  
pp. 105
Author(s):  
Regina Ama Banu ◽  
Jorge Matheu Alvarez ◽  
Anthony J. Reid ◽  
Wendemagegn Enbiale ◽  
Appiah-Korang Labi ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Resistance ◽  
Beta Lactamase ◽  
Extended Spectrum Beta Lactamase ◽  
River Waters ◽  
E Coli ◽  
Extended Spectrum ◽  
Two Cities ◽  
Animal Wastewater ◽  
Sources Of Contamination

Infections by Extended-Spectrum Beta-Lactamase producing Escherichia coli (ESBL-Ec) are on the increase in Ghana, but the level of environmental contamination with this organism, which may contribute to growing Antimicrobial Resistance (AMR), is unknown. Using the WHO OneHealth Tricycle Protocol, we investigated the contamination of E. coli (Ec) and ESBL-Ec in two rivers in Ghana (Odaw in Accra and Okurudu in Kasoa) that receive effluents from human and animal wastewater hotspots over a 12-month period. Concentrations of Ec, ESBL-Ec and percent ESBL-Ec/Ec were determined per 100 mL sample. Of 96 samples, 94 (98%) were positive for ESBL-Ec. concentrations per 100 mL (MCs100) of ESBL-Ec and %ESBL-Ec from both rivers were 4.2 × 104 (IQR, 3.1 × 103–2.3 × 105) and 2.79 (IQR, 0.96–6.03), respectively. MCs100 were significantly lower in upstream waters: 1.8 × 104 (IQR, 9.0 × 103–3.9 × 104) as compared to downstream waters: 1.9 × 106 (IQR, 3.7 × 105–5.4 × 106). Both human and animal wastewater effluents contributed to the increased contamination downstream. This study revealed high levels of ESBL-Ec in rivers flowing through two cities in Ghana. There is a need to manage the sources of contamination as they may contribute to the acquisition and spread of ESBL-Ec in humans and animals, thereby contributing to AMR.

scholarly journals Incidence and Antimicrobial Susceptibility of Escherichia coli and Klebsiella pneumoniae with Extended-Spectrum β-Lactamases in Community- and Hospital-Associated Intra-Abdominal Infections in Europe: Results of the 2008 Study for Monitoring Antimicrobial Resistance Trends (SMART)

2010 ◽  
Vol 54 (7) ◽  
pp. 3043-3046 ◽  
Author(s):  
Stephen P. Hawser ◽  
Samuel K. Bouchillon ◽  
Daryl J. Hoban ◽  
Robert E. Badal ◽  
Rafael Cantón ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Resistance ◽  
Klebsiella Pneumoniae ◽  
Antimicrobial Susceptibility ◽  
Beta Lactamase ◽  
Extended Spectrum Beta Lactamase ◽  
E Coli ◽  
Extended Spectrum ◽  
Abdominal Infections

ABSTRACT From 2002 to 2008, there was a significant increase in extended-spectrum beta-lactamase (ESBL)-positive Escherichia coli isolates in European intra-abdominal infections, from 4.3% in 2002 to 11.8% in 2008 (P < 0.001), but not for ESBL-positive Klebsiella pneumoniae isolates (16.4% to 17.9% [P > 0.05]). Hospital-associated isolates were more common than community-associated isolates, at 14.0% versus 6.5%, respectively, for E. coli (P < 0.001) and 20.9% versus 5.3%, respectively, for K. pneumoniae (P < 0.01). Carbapenems were consistently the most active drugs tested.

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