Antimicrobial susceptibility and pathogenicity of Escherichia coli strains of environmental origin

The study aimed to evaluate the antimicrobial susceptibility of 109 samples of Escherichia coli (E. coli) of environmental origin and to characterize these isolates according to the degree of pathogenicity in vivo, verifying a possible relationship between this variable and susceptibility to the active principles tested. The isolates were subjected to disc diffusion test to 14 antibiotics. From 16.5% to 90% of the samples were sensitive; 1 - 28.5% showed intermediate degree of susceptibility and between 9 to 78% of E. coli analyzed were resistant. The highest resistance percentages were seen in the class of quinolones and tetracyclines (>75%), and for sensitivity in the class of amphenicols (68.8%). By inoculating 1- day - old chicks, the isolates were classified as highly pathogenic (2.7%), intermediate (10.1%), low (42.2%) and apathogenic (45%). It was observed a wide variation in the susceptibility profile of isolates in relation to antimicrobials. It was also found that most of the samples had pathogenic potential (55%), thus being considered as APEC (avian pathogenic E. coli). No relationship between pathogenicity and antimicrobial susceptibility (P≤0.05) was observed.

Download Full-text

Avian pathogenic Escherichia coli (APEC) and uropathogenic Escherichia coli (UPEC): characterization and comparison

The Journal of Infection in Developing Countries ◽

10.3855/jidc.14217 ◽

2021 ◽

Vol 15 (07) ◽

pp. 962-971

Author(s):

Daniela Tonini da Rocha ◽

Felipe De Oliveira Salle ◽

Karen Apellanis Borges ◽

Thales Quedi Furian ◽

Vladimir Pinheiro do Nascimento ◽

...

Keyword(s):

Escherichia Coli ◽

Antimicrobial Susceptibility ◽

Antimicrobial Agents ◽

Resistance Rate ◽

Phylogenetic Groups ◽

Pathogenic Potential ◽

E Coli ◽

Antimicrobial Resistance Genes ◽

Tract Infections

Introduction: Avian pathogenic E. coli (APEC) and uropathogenic E. coli (UPEC) are responsible for avian colibacillosis and human urinary tract infections, respectively. There are genetic similarities between the APEC and UPEC pathotypes, suggesting the APEC strains could be a potential reservoir of virulence and antimicrobial-resistance genes for the UPEC strains. This study aimed to characterize and compare APEC and UPEC strains regarding the phylogroup classification, pathogenicity and antimicrobial susceptibility. Methodology: A total of 238 APEC and 184 UPEC strains were selected and characterized. The strains were assayed for antimicrobial susceptibility and classified into phylogenetic groups using a multiplex-PCR protocol. In addition, the APEC strains had previously been classified according to their in vivo pathogenicity. Results: The results showed that both pathotypes had variation in their susceptibility to most of the antimicrobial agents evaluated, with few strains classified as multidrug resistant. The highest resistance rate for both pathotypes was to amoxicillin. Classifying the APEC and UPEC strains into phylogenetic groups determined that the most frequently frequencies were for groups D and B2, respectively. These results reflect the pathogenic potential of these strains, as all the UPEC strains were isolated from unhealthy patients, and most of the APEC strains were previously classified as pathogenic. Conclusions: The results indicate that distribution into phylogenetic groups provided, in part, similar classification to those of in vivo pathogenicity index, as it was possible to adequately differentiate most of the pathogenic and commensal or low-pathogenicity bacteria. However, no relationship could be found between the specific antimicrobial agents and pathogenicity or phylogenetic group for either pathotype.

Download Full-text

In-vivo evaluation of pathogenicity and antimicrobial profile susceptibility from Escherichia coli samples isolated from commercial layer hens

Arquivos do Instituto Biológico ◽

10.1590/1808-1657000112016 ◽

2018 ◽

Vol 85 (0) ◽

Author(s):

Elisabete Aparecida Lopes Guastalli ◽

Marcos Roberto Buim ◽

Bruno Henrique Lopes Guastalli ◽

Fernando Antonio de Ávila

Keyword(s):

Escherichia Coli ◽

Antimicrobial Susceptibility ◽

Susceptibility Testing ◽

Pathogenicity Test ◽

Human Beings ◽

In Vivo Evaluation ◽

Highly Pathogenic ◽

Antimicrobial Sensitivity ◽

Layer Hens

ABSTRACT: Antimicrobial sensitivity and pathogenicity level of 90 strains of Escherichia coli isolated from livers and intestines from commercial layer hens presenting diarrhea were analyzed. To evaluate the antimicrobial susceptibility, all samples were subjected to antimicrobial susceptibility testing using 11 commercial drugs. The results have showed none of the strains was susceptible to all antibiotics tested. All samples showed resistance to two or more drugs. According to the mortality rate of the birds, the in-vivo pathogenicity test classifies the strains into four classes: high, intermediate, low and nonpathogenic. The test has showed 23 (25.5%) of the samples were highly pathogenic, 21 (23.3%) of intermediate pathogenicity, 23 (25.5%) low pathogenic, and 23 (25.5%) non-pathogenic. When the results of the classes of pathogenicity from isolates have been associated with antimicrobial susceptibility, nonpathogenic strains were less sensitive to the antibiotic ampicillin and increased sensitive to streptomycin antimicrobial compared to the others classes of pathogenic. Nonpathogenic strains showed resistance to many antimicrobials, an alert for poultry, since these bacteria might acquire the virulence genes and infect birds, others animals and even human beings.

Download Full-text

APLIKASI METODE BIOAUTOGRAFI DALAM PENELUSURAN DAYA ANTIBAKTERI EKSTRAK PEGAGAN (Centella asiatica (L.))

Jurnal Katalisator ◽

10.22216/jk.v5i1.5176 ◽

2020 ◽

Vol 5 (1) ◽

pp. 32

Author(s):

Rehmadanta Sitepu

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Centella Asiatica ◽

Ethanol Extract ◽

Disc Diffusion ◽

Diffusion Test ◽

E Coli ◽

Antibacterial Screening ◽

Bioactive Component ◽

Herbal Plant

Abstract Pegagan (Centella asiatica (L.) Urban) is a traditional herbal plant that spread as it grows and in bloom througout the year. Pegagan is believed to be able to cure various type of diseases because it contains bioactive component that’s good for human body. Pegagan’s bioactive component that has anti-bacterial properties are saponin, flavonoid, and tanin. This study was conducted with the purpose to determine the existence of antibacterial activity in ethanol extract of pegagan leaves by applying it in Disc Diffusion Test method against Escherichia coli and Staphylococcus aureus bacteria. Etanol extract was obtained by using maserasi method with 70% ethanol, separation of the active compound group which one of them is flavonoid using phytochemical screening, and the result was that the pegagan positively contains flavonoid, it was proven by the existence of a red marker on the tube. The result of active compund using methanol eluent: chloroform: glacial acetic acid produces 1 spot point on (Rf 0,5-0,7) on TLC. This spot was used in antibacterial screening by bioatugraphy method and the activity was detected qualitatively. Antibacterial activity was proved by Disc Diffusion Test which the results were ethanol extract on pegagan has inhibitory activity to E.coli and S. aureus. This study can be concluded that ethanol extract of Centella asiatica has a MIC value of 3,200 µg / mL both in E. Coli and S. aureus. The diameter of obstacles zone were 0,06±0,05 mm to E.coli and 0,04±0,019 mm to S. aureus. Abstrak Centella asiatica (L.) Urban (Pegagan) adalah spesies tumbuhan herbal tradisional dengan karakteristik tumbuh merambat dan berbunga di sepanjang tahun. Komponen bioaktif yang dimiliki pegagan dalam beberapa aspek, dapat digunakan dalam pengobatan penyakit. Golongan-golongan senyawa bioaktif pegagan yang memiliki daya antibakteri adalah saponin, flavonoid, dan tanin. Penelitian ini bertujuan untuk mengetahui adanya aktivitas antibakteri ekstrak etanol daun pegagan dengan metode Disc Diffusion Test pada Escherichia coli maupun Staphylococcus aureus. Ekstrak tanaman Pegagan diperoleh dengan maserasi dengan etanol 70%, pemisahan golongan senyawa aktif salah satunya flavonoid menggunakan skrining fitokimia, yang secara kualitatif menunjukkan ekstrak tanaman mengandung flavonoid. Hasil Kromatografi Lapis Tipis (KLT) senyawa aktif menggunakan eluen metanol: kloroform: asam asetat glasial menghasilkan 1 titik spot pada Rf 0,5-0,7 digunakan dalam penelusuran pengujian daya antibakteri dengan metode autobiografi dan menunjukkan adanya pembentukan zona bening. Pada uji kuantitatif, ekstrak etanol pegagan memiliki nilai KHM 3.200 µg/mL baik pada Eschericia coli maupun Staphylococcus aureus. Nilai Kadar Bunuh Minimum (KBM) lebih dari 6.400 µg/mL aktivitas daya hambat dengan diameter 0,06±0,05 mm pada E.coli dan 0,04±0,019 mm untuk S. aureus.

Download Full-text

ANTIBACTERIAL POTENTIAL OF L-TRYPTOPHAN ON EXTENDED-SPECTRUM BETALACTAMASE PRODUCING ESCHERICHIA COLI STRAINS: A PATHOLOGICAL PROMISING APPROACH

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2018.v11i7.25664 ◽

2018 ◽

Vol 11 (7) ◽

pp. 368 ◽

Cited By ~ 4

Author(s):

Saroj Kumar Sah ◽

Ubaid Rasool ◽

Shanthi B ◽

Jayprakash R ◽

Easwaramoorthy D ◽

...

Keyword(s):

Escherichia Coli ◽

Schiff Base ◽

Clinical Laboratory ◽

Antibacterial Properties ◽

Fourth Generation ◽

Disc Diffusion ◽

Diffusion Test ◽

Extended Spectrum Beta Lactamase ◽

E Coli ◽

Extended Spectrum

Objective: The main aim of this study was to determine the extended-spectrum beta-lactamase (ESBL) production among 83 isolates of Escherichia coli as well as the antibacterial effect of a novel compound, L-Tryptophan Schiff base, on 10 different ESBL positive strains of E. coli. Methods: Phenotypic ESBL activity in E. coli was confirmed by combined disc diffusion test according to clinical laboratory standard institute guidelines. Phenotypically positive ESBL clinical isolates were selected for molecular screening for synchronized detection of blaCTX-M-15 gene. Antibacterial activity of L-Tryptophan Schiff base was evaluated against ESBL positive isolates. The effect of L-Tryptophan Schiff base on a polymerase chain reaction (PCR) amplified a product of CTX-M-15 gene was also evaluated.Results: Antibiotic susceptibility screening showed resistance of ESBL positive isolates in the range of 18–96%. Disc diffusion test for phenotypic ESBL detection revealed that 99% (83/83) of isolates showed resistance to third and fourth generation cephalosporins (ceftazidime, cefotaxime, and cefepime) including ampicillin. L-Tryptophan Schiff base showed antimicrobial effect on E. coli. Molecular analysis for ESBL detection showed that 60% of strains were positive for blaCTX-M-15 gene. L-Tryptophan Schiff base also had downregulating effect on CTX-M-15 gene.Conclusion: This study presented an approach toward finding a suitable drug to reduce the serious infections caused by ESBL positive microorganisms. Phenotypic as well as molecular characterization was performed to get knowledge about the overall behavior of ESBL positive isolates of E. coli. L-Tryptophan Schiff base showed good antibacterial properties against ESBL positive isolates and a downregulating effect on PCR amplified product of CTX-M-15.

Download Full-text

Use of a modified disc diffusion test to detect ampc beta lactamase production in escherichia coli from cases of urinary tract infections

International Journal of Pharma and Bio Sciences ◽

10.22376/ijpbs.2016.7.4.b579-583 ◽

2016 ◽

Vol 7 (4) ◽

Author(s):

MAANASA BHASKAR M ◽

JHARNA MANDAL

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Urinary Tract Infections ◽

Beta Lactamase ◽

Disc Diffusion ◽

Diffusion Test ◽

Tract Infections

Download Full-text

Characterization and in Vivo Cloning of prlC, a Suppressor of Signal Sequence Mutations in Escherichia coli K12

Genetics ◽

10.1093/genetics/116.4.513 ◽

1987 ◽

Vol 116 (4) ◽

pp. 513-521

Author(s):

Nancy J Trun ◽

Thomas J Silhavy

Keyword(s):

Escherichia Coli ◽

Genetic Mapping ◽

Signal Sequence ◽

Illegitimate Recombination ◽

Mutant Phenotype ◽

E Coli ◽

Physical Location ◽

Sequence Deletion ◽

New Alleles

ABSTRACT The prlC gene of E. coli was originally identified as an allele, prlC1, which suppresses certain signal sequence mutations in the genes for several exported proteins. We have isolated six new alleles of prlC that also confer this phenotype. These mutations can be placed into three classes based on the degree to which they suppress the lamBsignal sequence deletion, lamBs78. Genetic mapping reveals that the physical location of the mutations in prlC correlates with the strength of the suppression, suggesting that different regions of the gene can be altered to yield a suppressor phenotype. We also describe an in vivo cloning procedure using λplacMu9H. The procedure relies on transposition and illegitimate recombination to generate a specialized transducing phage that carries prlC1. This method should be applicable to any gene for which there is a mutant phenotype.

Download Full-text

Mechanistic insights into synergy between nalidixic acid and tetracycline against clinical isolates of Acinetobacter baumannii and Escherichia coli

Communications Biology ◽

10.1038/s42003-021-02074-5 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Amit Gaurav ◽

Varsha Gupta ◽

Sandeep K. Shrivastava ◽

Ranjana Pathania

Keyword(s):

Escherichia Coli ◽

Acinetobacter Baumannii ◽

Nalidixic Acid ◽

Bacterial Infections ◽

Clinical Isolates ◽

Hospital Environment ◽

Infection Model ◽

Drug Resistant ◽

E Coli

AbstractThe increasing prevalence of antimicrobial resistance has become a global health problem. Acinetobacter baumannii is an important nosocomial pathogen due to its capacity to persist in the hospital environment. It has a high mortality rate and few treatment options. Antibiotic combinations can help to fight multi-drug resistant (MDR) bacterial infections, but they are rarely used in the clinics and mostly unexplored. The interaction between bacteriostatic and bactericidal antibiotics are mostly reported as antagonism based on the results obtained in the susceptible model laboratory strain Escherichia coli. However, in the present study, we report a synergistic interaction between nalidixic acid and tetracycline against clinical multi-drug resistant A. baumannii and E. coli. Here we provide mechanistic insight into this dichotomy. The synergistic combination was studied by checkerboard assay and time-kill curve analysis. We also elucidate the mechanism behind this synergy using several techniques such as fluorescence spectroscopy, flow cytometry, fluorescence microscopy, morphometric analysis, and real-time polymerase chain reaction. Nalidixic acid and tetracycline combination displayed synergy against most of the MDR clinical isolates of A. baumannii and E. coli but not against susceptible isolates. Finally, we demonstrate that this combination is also effective in vivo in an A. baumannii/Caenorhabditis elegans infection model (p < 0.001)

Download Full-text

Phenotypic Antimicrobial Susceptibility of Escherichia coli from Raw Meats, Ready-to-Eat Meats, and Their Related Samples in One Health Context

Microorganisms ◽

10.3390/microorganisms9020326 ◽

2021 ◽

Vol 9 (2) ◽

pp. 326

Author(s):

Frederick Adzitey ◽

Nurul Huda ◽

Amir Husni Mohd Shariff

Keyword(s):

Escherichia Coli ◽

Antimicrobial Resistance ◽

Antimicrobial Susceptibility ◽

Resistance Index ◽

Diffusion Method ◽

Resistant Bacteria ◽

Disk Diffusion Method ◽

E Coli ◽

The Usa ◽

Raw Meats

Meat is an important food source that can provide a significant amount of protein for human development. The occurrence of bacteria that are resistant to antimicrobials in meat poses a public health risk. This study evaluated the occurrence and antimicrobial resistance of E. coli (Escherichia coli) isolated from raw meats, ready-to-eat (RTE) meats and their related samples in Ghana. E. coli was isolated using the USA-FDA Bacteriological Analytical Manual and phenotypic antimicrobial susceptibility test was performed by the disk diffusion method. Of the 200 examined meats and their related samples, 38% were positive for E. coli. Notably, E. coli was highest in raw beef (80%) and lowest in RTE pork (0%). The 45 E. coli isolates were resistant ≥ 50% to amoxicillin, trimethoprim and tetracycline. They were susceptible to azithromycin (87.1%), chloramphenicol (81.3%), imipenem (74.8%), gentamicin (72.0%) and ciprofloxacin (69.5%). A relatively high intermediate resistance of 33.0% was observed for ceftriaxone. E. coli from raw meats, RTE meats, hands of meat sellers and working tools showed some differences and similarities in their phenotypic antimicrobial resistance patterns. Half (51.1%) of the E. coli isolates exhibited multidrug resistance. The E. coli isolates showed twenty-two different resistant patterns, with a multiple antibiotic resistance index of 0.0 to 0.7. The resistant pattern amoxicillin (A, n = 6 isolates) and amoxicillin-trimethoprim (A-TM, n = 6 isolates) were the most common. This study documents that raw meats, RTE meats and their related samples in Ghana are potential sources of antimicrobial-resistant E. coli and pose a risk for the transfer of resistant bacteria to the food chain, environment and humans.

Download Full-text

Lysyl-tRNA synthetase from Escherichia coli K12. Chromatographic heterogeneity and the lysU-gene product

Biochemical Journal ◽

10.1042/bj2480043 ◽

1987 ◽

Vol 248 (1) ◽

pp. 43-51 ◽

Cited By ~ 17

Author(s):

J Charlier ◽

R Sanchez

Keyword(s):

Escherichia Coli ◽

Gene Product ◽

Activity Ratio ◽

Deae Cellulose ◽

Trna Synthetase ◽

Trna Synthetases ◽

E Coli ◽

Aminoacyl Trna Synthetases

In contrast with most aminoacyl-tRNA synthetases, the lysyl-tRNA synthetase of Escherichia coli is coded for by two genes, the normal lysS gene and the inducible lysU gene. During its purification from E. coli K12, lysyl-tRNA synthetase was monitored by its aminoacylation and adenosine(5′)tetraphospho(5′)adenosine (Ap4A) synthesis activities. Ap4A synthesis was measured by a new assay using DEAE-cellulose filters. The heterogeneity of lysyl-tRNA synthetase (LysRS) was revealed on hydroxyapatite; we focused on the first peak, LysRS1, because of its higher Ap4A/lysyl-tRNA activity ratio at that stage. Additional differences between LysRS1 and LysRS2 (major peak on hydroxyapatite) were collected. LysRS1 was eluted from phosphocellulose in the presence of the substrates, whereas LysRS2 was not. Phosphocellulose chromatography was used to show the increase of LysRS1 in cells submitted to heat shock. Also, the Mg2+ optimum in the Ap4A-synthesis reaction is much higher for LysRS1. LysRS1 showed a higher thermostability, which was specifically enhanced by Zn2+. These results in vivo and in vitro strongly suggest that LysRS1 is the heat-inducible lysU-gene product.

Download Full-text

Antimicrobial susceptibility and diarrheagenic diagnosis of Escherichia coli and Salmonella enterica isolated from feral pigeons (Columba livia) captured in Fortaleza, Brazil

Pesquisa Veterinária Brasileira ◽

10.1590/1678-5150-pvb-5633 ◽

2018 ◽

Vol 38 (11) ◽

pp. 2150-2154 ◽

Cited By ~ 2

Author(s):

Ruben V. Horn ◽

Windleyanne G.A. Bezerra ◽

Elisângela S. Lopes ◽

Régis S.C. Teixeira ◽

Isaac N.G. Silva ◽

...

Keyword(s):

Escherichia Coli ◽

Antimicrobial Resistance ◽

Clavulanic Acid ◽

Antimicrobial Susceptibility ◽

Salmonella Enterica ◽

Columba Livia ◽

Susceptibility Test ◽

Antimicrobial Susceptibility Test ◽

E Coli ◽

Feral Pigeons

ABSTRACT: This study aimed to isolate Escherichia coli and Salmonella enterica from captured feral pigeons in Fortaleza, Brazil, and, in addition to evaluate the antimicrobial susceptibility profiles and diagnose diarrheagenic E. coli strains. Pigeons were captured in four public locations in Fortaleza with three techniques. Individual cloacal swab samples were collected and submitted to bacterial isolation, biochemical identification and antimicrobial susceptibility test. Disk diffusion technique was used with twelve antibiotics. E. coli strains were submitted to DNA extraction followed by PCR to diagnose five diarrheagenic pathotypes. A total of 124 birds were captured. One bird was positive for Salmonella enterica (0.81%) and 121 (97.58%) were positive for E. coli. Among these, 110 isolates were submitted to antimicrobial susceptibility test and 28.18% (31/110) presented resistance to at least one antibiotic. Resistance to azithromycin was the most frequent (21.82%), followed by tetracycline (10.91%) and sulfamethoxazole with trimethoprim (8.9%). Multidrug resistance, calculated as a resistance to at least 3 antimicrobial classes, was identified in 3.64% (4/110) of strains. The maximum number of antimicrobial classes to which one strain was resistant was seven. Results demonstrated nine different resistance profiles and the most frequent was tetracycline and sulfamethoxazole with trimethoprim (4 strains), followed by chloramphenicol, azithromycin, tetracycline and sulfamethoxazole with trimethoprim (3 strains). Amoxicillin with clavulanic acid and tobramycin presented lowest levels of antimicrobial resistance, to which none of the tested strains were resistant. A single strain was positive for the eltB gene, which is a diagnostic tool to identify the Enterotoxigenic E. coli (ETEC) pathotype. None of the other investigated genes (stx1, stx2, estA, eaeA, ipaH, aatA and aaiC) were identified. The single isolate of S. enterica was a rough strain of Salmonella enterica subsp. enterica, but serotype identification was not possible. However, this isolate presented resistance to amoxicillin, amoxicillin with clavulanic acid, tetracycline and sulfamethoxazole with trimethoprim. Therefore, captured feral pigeons of Fortaleza presented a low prevalence of S. enterica and diarrheagenic E. coli. Considering the investigated pathogens, our results suggest a good health status and a low public health risk. However, important antimicrobial resistance profiles were identified.

Download Full-text