scholarly journals A TEM-derived extended-spectrum beta-lactamase in Pseudomonas aeruginosa.

1996 ◽  
Vol 40 (11) ◽  
pp. 2488-2493 ◽  
Author(s):  
P Mugnier ◽  
P Dubrous ◽  
I Casin ◽  
G Arlet ◽  
E Collatz
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Clinical Strain ◽  
Beta Lactamase ◽  
Beta Lactam ◽  
Aminoglycoside Resistance ◽  
Double Mutation ◽  
Extended Spectrum Beta Lactamase ◽  
Beta Lactam Antibiotics ◽  
Extended Spectrum ◽  
High Level

A clinical strain of Pseudomonas aeruginosa, PAe1100, was found to be resistant to all antipseudomonal beta-lactam antibiotics and to aminoglycosides, including gentamicin, amikacin, and isepamicin. PAe1100 produced two beta-lactamases, TEM-2 (pI 5.6) and a novel, TEM-derived extended-spectrum beta-lactamase called TEM-42 (pI 5.8), susceptible to inhibition by clavulanate, sulbactam, and tazobactam. Both enzymes, as well as the aminoglycoside resistance which resulted from AAC(3)-IIa and AAC(6')-I production, were encoded by an 18-kb nonconjugative plasmid, pLRM1, that could be transferred to Escherichia coli by transformation. The gene coding for TEM-42 had four mutations that led to as many amino acid substitutions with respect to TEM-2: Val for Ala at position 42 (Ala42), Ser for Gly238, Lys for Glu240, and Met for Thr265 (Ambler numbering). The double mutation Ser for Gly238 and Lys for Glu240, which has so far only been described in SHV-type but not TEM-type enzymes, conferred concomitant high-level resistance to cefotaxime and ceftazidime. The novel, TEM-derived extended-spectrum beta-lactamase appears to be the first of its class to be described in P. aeruginosa.

scholarly journals Presence of different beta-lactamase classes among clinical isolates of Pseudomonas aeruginosa expressing AmpC beta-lactamase enzyme

2010 ◽  
Vol 4 (04) ◽  
pp. 239-242 ◽  
Author(s):  
Supriya Upadhyay ◽  
Malay Ranjan Sen ◽  
Amitabha Bhattacharjee
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Treatment Options ◽  
Clinical Isolates ◽  
Diffusion Method ◽  
Beta Lactamase ◽  
Beta Lactam ◽  
Disk Diffusion Method ◽  
Extended Spectrum Beta Lactamase ◽  
Extended Spectrum ◽  
Enzyme Detection

Introduction: Infections caused by Pseudomonas aeruginosa are difficult to treat as the majority of isolates exhibit varying degrees of beta-lactamase mediated resistance to most of the beta-lactam antibiotics. It is also not unusual to find a single isolate that expresses multiple β-lactamase enzymes, further complicating the treatment options. Thus the present study was designed to investigate the coexistence of different beta-lactamase enzymes in clinical isolates of P. aeruginosa. Methodology: A total of 202 clinical isolates of P. aeruginosa were tested for the presence of AmpC beta-lactamase, extended spectrum beta-lactamase (ESBL) and metallo beta-lactamase (MBL) enzyme. Detection of AmpC beta-lactamase was performed by disk antagonism test and a modified three-dimensional method, whereas detection of ESBL was done by the combined disk diffusion method per Clinical and Laboratory Standards Institute (CLSI) guidelines and MBL were detected by the Imipenem EDTA disk potentiation test. Results: A total of 120 (59.4%) isolates were confirmed to be positive for AmpC beta-lactamase. Among them, 14 strains (7%) were inducible AmpC producers. Co-production of AmpC along with extended spectrum beta-lactamase and metallo beta-lactamase was reported in 3.3% and 46.6% isolates respectively. Conclusion: The study emphasizes the high prevalence of multidrug resistant P. aeruginosa producing beta-lactamase enzymes of diverse mechanisms. Thus proper antibiotic policy and measures to restrict the indiscriminative use of cephalosporins and carbapenems should be taken to minimize the emergence of this multiple beta-lactamase producing pathogens.

scholarly journals Characterization of Multidrug Resistant Extended-Spectrum Beta-Lactamase-ProducingEscherichia coliamong Uropathogens of Pediatrics in North of Iran

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Mohammad Sadegh Rezai ◽  
Ebrahim Salehifar ◽  
Alireza Rafiei ◽  
Taimour Langaee ◽  
Mohammadreza Rafati ◽  
...  
Keyword(s):  
Antimicrobial Resistance ◽  
Multidrug Resistant ◽  
Beta Lactamase ◽  
Beta Lactam ◽  
Extended Spectrum Beta Lactamase ◽  
E Coli ◽  
Beta Lactam Antibiotics ◽  
Extended Spectrum ◽  
Extended Spectrum Beta Lactamases ◽  
North Of Iran

Escherichia coliremains as one of the most important bacteria causing infections in pediatrics and producing extended-spectrum beta-lactamases (ESBLs) making them resistant to beta-lactam antibiotics. In this study we aimed to genotype ESBL-producingE. coliisolates from pediatric patients for ESBL genes and determine their association with antimicrobial resistance. One hundred of theE. coliisolates were initially considered ESBL producing based on their MIC results. These isolates were then tested by polymerase chain reaction (PCR) for the presence or absence ofCTX,TEM,SHV,GES, andVEBbeta-lactamase genes. About 30.5% of isolatedE. coliwas ESBL-producing strain. TheTEMgene was the most prevalent (49%) followed bySHV(44%),CTX(28%),VEB(8%), andGES(0%) genes. The ESBL-producingE. coliisolates were susceptible to carbapenems (66%) and amikacin (58%) and showed high resistance to cefixime (99%), colistin (82%), and ciprofloxacin (76%). In conclusion, carbapenems were the most effective antibiotics against ESBl-producingE. coliin urinary tract infection in North of Iran. The most prevalent gene is the TEM-type, but the other resistant genes and their antimicrobial resistance are on the rise.

scholarly journals First Global Report of Plasmid-Mediated mcr-1 and Extended-Spectrum Beta-Lactamase-Producing Escherichia coli from Sheep in Portugal

Antibiotics ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1403
Author(s):  
Josman Dantas Palmeira ◽  
Marisa Haenni ◽  
Jean-Yves Madec ◽  
Helena Maria Neto Ferreira
Keyword(s):  
One Health ◽  
Diffusion Method ◽  
Beta Lactamase ◽  
Beta Lactam ◽  
Colistin Resistance ◽  
Disk Diffusion Method ◽  
Extended Spectrum Beta Lactamase ◽  
E Coli ◽  
Beta Lactam Antibiotics ◽  
Extended Spectrum

Resistances to extended-spectrum cephalosporins (ESC) and colistin are One Health issues since genes encoding these resistances can be transmitted between all sectors of the One Health concept, i.e., human, animal, and the environment. Among food-producing animals, sheep farming has long been overlooked. To fill in this knowledge gap, we looked for ESC- and colistin resistance in 21 faecal samples collected from sheep in one farm in the south of Portugal. ESC-resistant isolates were selected on MacConkey agar plates supplemented with cefotaxime. Susceptibility testing was performed by the disk-diffusion method according to CLSI, while colistin MIC was determined by broth microdilution. ESC- and colistin-resistance genes were identified by PCR, and the clonality of all isolates was assessed by XbaI-PFGE. The replicon content was determined by PCR according to the PCR-based replicon typing (PBRT) scheme. Sixty-two non-duplicate ESC-resistant E. coli isolates were identified, which all presented an extended-spectrum beta-lactamase (ESBL) phenotype, mostly due to the presence of CTX-M genes. One CTX-M-1-producing E. coli was concomitantly colistin-resistant and presented the plasmid-mediated mcr-1 gene. Nearly all isolates showed associated resistances to non-beta-lactam antibiotics, which could act as co-selectors, even in the absence of beta-lactam use. The results showed a high proportion of ESBL-producing E. coli in sheep faeces. Their dissemination was very dynamic, with the spread of successful clones between animals, but also a large diversity of clones and plasmids, sometimes residing in the same animal. This study highlights the need for global surveillance in all food-producing sectors, in order to avoid the dissemination of genes conferring resistance to last-resort antibiotics in human medicine.

Detection of CTX-M-Type Extended-Spectrum Beta-Lactamase Producing Salmonella Typhimurium in Commercial Poultry Farms in Copperbelt Province, Zambia

2021 ◽  
Vol 1 (2) ◽  
pp. 27-34
Author(s):  
Naomi Kaonga ◽  
Bernard. M. Hang’ombe ◽  
Athumani. M. Lupindu ◽  
Abubakar. S. Hoza
Keyword(s):  
Salmonella Typhimurium ◽  
Beta Lactamase ◽  
Beta Lactam ◽  
Protection Measures ◽  
Extended Spectrum Beta Lactamase ◽  
Beta Lactam Antibiotics ◽  
Extended Spectrum ◽  
Wide Range ◽  
Poultry Farms ◽  
Commercial Poultry

In Zambia, poultry is a rapidly increasing sector contributing 4.8% of the Agricultural Gross Domestic Product (GDP), thus providing a significant income-generating activity. Worldwide, poultry is a major reservoir of Salmonella with an increasing incidence of extended-spectrum beta-lactamase (ESBL) producing strains. ESBLs are enzymes produced by bacteria and are capable of inactivating a wide range of beta-lactam antibiotics. Salmonella enterica serovars Enteritidis and Typhimurium are the most important foodborne serotypes in many countries, infecting both humans and animals and are transmitted to humans through the food supply chain. CTX-M ESBLs have been described in Salmonella Typhimurium isolates with resistant genes located on transferable plasmids. This study aimed to detect S. Typhimurium, their antimicrobial resistance, and CTX-M-type ESBL Producing strains in commercial poultry farms in Copperbelt Province, Zambia. Five districts were considered for this study, where one poultry farm per district was randomly selected for sampling. An overall number of 384 fecal samples were analyzed using microbiological and molecular methods. S. Typhimurium was detected at 17.7% (CI: 14.2%-21.8%) in commercial poultry farms in Copperbelt Province, of which 12.8% (CI: 9.8%-16.5%) were found harboring the CTX-M-Type ESBL genes. S. Typhimurium isolates showed 88.2% resistance to at least one antimicrobial compound. All the isolates showed 100% resistance to tetracycline, followed by ampicillin and amoxicillin at 91.2%. These isolates also showed 58.8% resistance to cefotaxime and 54.4% to ceftazidime. Detection of CTX-M ESBL producing Salmonella Typhimurium suggests the contamination of chicken food chain at farm level and calls for public health protection measures.

scholarly journals PCR Detection of Some ESBLs (bla) Genes in Pseudomonas aeruginosa Isolated from Burn’s Units in Bagdad Hospitals

2015 ◽  
Vol 9 (2) ◽  
pp. 74-80
Author(s):  
Asmaa A. . AL-Kaisse ◽  
Amina N. AL-Thwani ◽  
Rabab Q. AL-Segar
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Dna Analysis ◽  
Beta Lactamase ◽  
Drug Resistant ◽  
Beta Lactam ◽  
Beta Lactamases ◽  
Extended Spectrum Beta Lactamase ◽  
Extended Spectrum ◽  
Burn Units ◽  
Severe Infections

Multi drug resistant (MDR) and Extended Spectrum Beta Lactamase (ESBLs) of Pseudomonas aeruginosawere detected. Pseudomonas aeruginosa is a bacterium responsible for severe infections in burn’s units,plasmid DNA analysis and encoded many types of genes responsible for beta-lactamases. To determine thetype of genes responsible for beta-lactam broad spectrum in P. aeruginosa strains isolated from 100 swabsof burn’s units environment, using a molecular methods (PCR) by primers specific to ESBLs (bla ) genesoxacillin hydrolyzing capabilities OXA-10, OXA-4 and Vietnam Extended-Spectrum β-Lactame VEB-1.The results revealed that 15 strains were isolated from burn units environment. All of 15 (100%) werepositive OXA-10 and only one (6.6%) for OXA-4 while the other gene VEB-1 was found in 6 (40%) isolates.تم 

scholarly journals Coproduction of Extended Spectrum, AmpC and Metallo β- Lactamases in Pseudomonas aeruginosa Isolates from a Super Speciality Center

2021 ◽  
Vol 10 (10) ◽  
pp. 176-184
Author(s):  
Ashna Bhasin Poonam Loomba ◽  
Abha Sharma Bibhabati Mishra ◽  
Ashish Bajaj
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Treatment Options ◽  
Multidrug Resistant ◽  
Clinical Isolates ◽  
Diffusion Method ◽  
Beta Lactamase ◽  
Beta Lactam ◽  
Disk Diffusion Method ◽  
Extended Spectrum Beta Lactamase ◽  
Extended Spectrum

Pseudomonas aeruginosa (P. aeruginosa) is one of the leading causes of hospital as well as community acquired infections. They’re strenuous to treat as most of isolates exhibit various degrees of beta- lactamase mediated resistance to majority of the beta-lactam antibiotics. Single isolate can express multiple β- lactamase enzymes, further limiting the treatment options. Therefore, this study was outlined to research the coexistence of various beta-lactamase enzymes in clinical isolates of P. aeruginosa. The aim of the study was to detect the co-prevalence of Extended Spectrum Beta lactmases (ESBL), AmpC and Metallo β-Lactamases (MBL) in Pseudomonas aeruginosa isolates from a superspeciality center. Fifty clinical isolates of P. aeruginosa were tested for the presence of AmpC beta-lactamase, extended spectrum beta- lactamase (ESBL) and metallo beta-lactamase (MBL) enzyme. Discernment of AmpC beta-lactamase was performed by disk antagonism while ESBL detection was done by the combined disk diffusion method as per Clinical and Laboratory Standards Institute (CLSI) guidelines and MBL were detected by the Imipenem EDTA disk potentiation test. Eleven of 50 (22%) isolates were confirmed to be positive for AmpC and Extended spectrum beta lactamases. Co-production of AmpC along side ESBL and MBL was reported in 12 % isolates. The study shows the high prevalence of multidrug resistant P. aeruginosa producing beta-lactamase enzymes of diverse mechanisms. Consequently, formulation of a correct antibiotic policy and taking measures to restrict the indiscriminative use of cephalosporins and carbapenems should be taken to mitigate the emergence of this multiple beta-lactamase producing pathogens.

scholarly journals Conjugative Plasmids Disseminating CTX-M-15 among Human, Animals and the Environment in Mwanza Tanzania: A Need to Intensify One Health Approach

Antibiotics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 836
Author(s):  
Caroline A. Minja ◽  
Gabriel Shirima ◽  
Stephen E. Mshana
Keyword(s):  
One Health ◽  
Animal Origin ◽  
Beta Lactamase ◽  
Beta Lactam ◽  
Beta Lactamases ◽  
Extended Spectrum Beta Lactamase ◽  
Beta Lactam Antibiotics ◽  
Extended Spectrum ◽  
Plasmid Replicon ◽  
Susceptibility Tests

Background: Globally, blaCTX-M-15 beta-lactamases are the most popular extended spectrum beta-lactamase alleles that are widely distributed due its mobilisation by mobile genetic elements in several compartments. We aimed to determine the conjugation frequencies and replicon types associated with plasmids carrying blaCTX-M-15 gene from Extended Spectrum Beta-lactamase producing isolates in order to understand the dissemination of resistance genes in different compartments. Material and methods: A total of 51 archived isolates carrying blaCTX-M-15 beta-lactamases were used as donors in this study. Antibiotic susceptibility tests were performed as previously described for both donors and transconjugants. Conjugation experiment was performed by a modified protocol of the plate mating experiment, and plasmid replicon types were screened among donor and transconjugant isolates by multiplex Polymerase Chain Reaction in a set of three primer panels. Results: The conjugation efficiency of plasmids carrying blaCTX-M-15 was 88.2% (45/51) with conjugation frequencies in the order of 10−1 to 10−9 and a 100% transfer efficiency observed among E. coli of animal origin. Majority of donors (n = 21) and transconjugants (n = 14) plasmids were typed as either Inc FIA or Inc FIB. Resistance to non-beta-lactam antibiotics was transferrable in 34/45 (75.6%) of events. Ciprofloxacin, tetracycline and sulphamethoxazole-trimethoprim resistance was co-transferred in 29/34 (85.3%) such events. Gentamicin resistance was transferred in 17/34 (50%) of events. Conclusions: Majority of plasmids carrying blaCTX-M-15 were conjugatively transferred by IncF plasmids along with non-beta lactam resistance. There is a need for more research on plasmids to understand how plasmids especially multi replicon plasmids interact and the effect of such interaction on conjugation. One Health approach is to be intensified to address antimicrobial resistance which is a public health threat.

Current Perspectives on Extended-Spectrum Beta-Lactamase–Producing Gram-Negative Bacilli

2008 ◽  
Vol 21 (5) ◽  
pp. 338-345
Author(s):  
Brad M. Wright ◽  
Edward H. Eiland
Keyword(s):  
Patient Outcomes ◽  
Beta Lactamase ◽  
Beta Lactam ◽  
Gram Negative ◽  
Extended Spectrum Beta Lactamase ◽  
Beta Lactam Antibiotics ◽  
Poor Patient ◽  
Extended Spectrum ◽  
Care Costs ◽  
Selection Of

Beta-lactamase enzymes produced by gram-negative bacilli were identified before the first beta-lactam antibiotics were used to treat infections. As these enzymes adapted to available beta-lactam agents, newer beta-lactam agents were developed. Development and widespread use of the oxyimino-cephalosporins led to the emergence of extended-spectrum beta-lactamase enzymes that hydrolyze the penicillins, extended-spectrum cephalosporins, and aztreonam. There are now over 200 recognized ESBLs in a variety of gram-negative bacilli conferring resistance to penicillins, cephalosporins, a monobactam, and even carbapenems. The emergence of these enzymes is associated with poor patient outcomes, increased total health care costs, and more carbapenem use. Carbapenems should be selected judiciously to optimize outcomes while preventing further selection of extended-spectrum beta-lactamase resistance.

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